Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 8214 insertions, 0 deletions

diff --git a/drivers/char/synclink.c b/drivers/char/synclink.c
new file mode 100644
index 000000000000..37c8bea8e2b0
--- /dev/null
+++ b/drivers/char/synclink.c
@@ -0,0 +1,8214 @@
+/*
+ * linux/drivers/char/synclink.c
+ *
+ * $Id: synclink.c,v 4.28 2004/08/11 19:30:01 paulkf Exp $
+ *
+ * Device driver for Microgate SyncLink ISA and PCI
+ * high speed multiprotocol serial adapters.
+ *
+ * written by Paul Fulghum for Microgate Corporation
+ * paulkf@microgate.com
+ *
+ * Microgate and SyncLink are trademarks of Microgate Corporation
+ *
+ * Derived from serial.c written by Theodore Ts'o and Linus Torvalds
+ *
+ * Original release 01/11/99
+ *
+ * This code is released under the GNU General Public License (GPL)
+ *
+ * This driver is primarily intended for use in synchronous
+ * HDLC mode. Asynchronous mode is also provided.
+ *
+ * When operating in synchronous mode, each call to mgsl_write()
+ * contains exactly one complete HDLC frame. Calling mgsl_put_char
+ * will start assembling an HDLC frame that will not be sent until
+ * mgsl_flush_chars or mgsl_write is called.
+ * 
+ * Synchronous receive data is reported as complete frames. To accomplish
+ * this, the TTY flip buffer is bypassed (too small to hold largest
+ * frame and may fragment frames) and the line discipline
+ * receive entry point is called directly.
+ *
+ * This driver has been tested with a slightly modified ppp.c driver
+ * for synchronous PPP.
+ *
+ * 2000/02/16
+ * Added interface for syncppp.c driver (an alternate synchronous PPP
+ * implementation that also supports Cisco HDLC). Each device instance
+ * registers as a tty device AND a network device (if dosyncppp option
+ * is set for the device). The functionality is determined by which
+ * device interface is opened.
+ *
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#if defined(__i386__)
+#  define BREAKPOINT() asm("   int $3");
+#else
+#  define BREAKPOINT() { }
+#endif
+
+#define MAX_ISA_DEVICES 10
+#define MAX_PCI_DEVICES 10
+#define MAX_TOTAL_DEVICES 20
+
+#include <linux/config.h>	
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/timer.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <linux/major.h>
+#include <linux/string.h>
+#include <linux/fcntl.h>
+#include <linux/ptrace.h>
+#include <linux/ioport.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+
+#include <linux/netdevice.h>
+
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <asm/serial.h>
+
+#include <linux/delay.h>
+#include <linux/ioctl.h>
+
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/dma.h>
+#include <linux/bitops.h>
+#include <asm/types.h>
+#include <linux/termios.h>
+#include <linux/workqueue.h>
+#include <linux/hdlc.h>
+
+#ifdef CONFIG_HDLC_MODULE
+#define CONFIG_HDLC 1
+#endif
+
+#define GET_USER(error,value,addr) error = get_user(value,addr)
+#define COPY_FROM_USER(error,dest,src,size) error = copy_from_user(dest,src,size) ? -EFAULT : 0
+#define PUT_USER(error,value,addr) error = put_user(value,addr)
+#define COPY_TO_USER(error,dest,src,size) error = copy_to_user(dest,src,size) ? -EFAULT : 0
+
+#include <asm/uaccess.h>
+
+#include "linux/synclink.h"
+
+#define RCLRVALUE 0xffff
+
+static MGSL_PARAMS default_params = {
+	MGSL_MODE_HDLC,			/* unsigned long mode */
+	0,				/* unsigned char loopback; */
+	HDLC_FLAG_UNDERRUN_ABORT15,	/* unsigned short flags; */
+	HDLC_ENCODING_NRZI_SPACE,	/* unsigned char encoding; */
+	0,				/* unsigned long clock_speed; */
+	0xff,				/* unsigned char addr_filter; */
+	HDLC_CRC_16_CCITT,		/* unsigned short crc_type; */
+	HDLC_PREAMBLE_LENGTH_8BITS,	/* unsigned char preamble_length; */
+	HDLC_PREAMBLE_PATTERN_NONE,	/* unsigned char preamble; */
+	9600,				/* unsigned long data_rate; */
+	8,				/* unsigned char data_bits; */
+	1,				/* unsigned char stop_bits; */
+	ASYNC_PARITY_NONE		/* unsigned char parity; */
+};
+
+#define SHARED_MEM_ADDRESS_SIZE 0x40000
+#define BUFFERLISTSIZE (PAGE_SIZE)
+#define DMABUFFERSIZE (PAGE_SIZE)
+#define MAXRXFRAMES 7
+
+typedef struct _DMABUFFERENTRY
+{
+	u32 phys_addr;	/* 32-bit flat physical address of data buffer */
+	u16 count;	/* buffer size/data count */
+	u16 status;	/* Control/status field */
+	u16 rcc;	/* character count field */
+	u16 reserved;	/* padding required by 16C32 */
+	u32 link;	/* 32-bit flat link to next buffer entry */
+	char *virt_addr;	/* virtual address of data buffer */
+	u32 phys_entry;	/* physical address of this buffer entry */
+} DMABUFFERENTRY, *DMAPBUFFERENTRY;
+
+/* The queue of BH actions to be performed */
+
+#define BH_RECEIVE  1
+#define BH_TRANSMIT 2
+#define BH_STATUS   4
+
+#define IO_PIN_SHUTDOWN_LIMIT 100
+
+#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
+
+struct	_input_signal_events {
+	int	ri_up;	
+	int	ri_down;
+	int	dsr_up;
+	int	dsr_down;
+	int	dcd_up;
+	int	dcd_down;
+	int	cts_up;
+	int	cts_down;
+};
+
+/* transmit holding buffer definitions*/
+#define MAX_TX_HOLDING_BUFFERS 5
+struct tx_holding_buffer {
+	int	buffer_size;
+	unsigned char *	buffer;
+};
+
+
+/*
+ * Device instance data structure
+ */
+ 
+struct mgsl_struct {
+	int			magic;
+	int			flags;
+	int			count;		/* count of opens */
+	int			line;
+	int                     hw_version;
+	unsigned short		close_delay;
+	unsigned short		closing_wait;	/* time to wait before closing */
+	
+	struct mgsl_icount	icount;
+	
+	struct tty_struct 	*tty;
+	int			timeout;
+	int			x_char;		/* xon/xoff character */
+	int			blocked_open;	/* # of blocked opens */
+	u16			read_status_mask;
+	u16			ignore_status_mask;	
+	unsigned char 		*xmit_buf;
+	int			xmit_head;
+	int			xmit_tail;
+	int			xmit_cnt;
+	
+	wait_queue_head_t	open_wait;
+	wait_queue_head_t	close_wait;
+	
+	wait_queue_head_t	status_event_wait_q;
+	wait_queue_head_t	event_wait_q;
+	struct timer_list	tx_timer;	/* HDLC transmit timeout timer */
+	struct mgsl_struct	*next_device;	/* device list link */
+	
+	spinlock_t irq_spinlock;		/* spinlock for synchronizing with ISR */
+	struct work_struct task;		/* task structure for scheduling bh */
+
+	u32 EventMask;			/* event trigger mask */
+	u32 RecordedEvents;		/* pending events */
+
+	u32 max_frame_size;		/* as set by device config */
+
+	u32 pending_bh;
+
+	int bh_running;		/* Protection from multiple */
+	int isr_overflow;
+	int bh_requested;
+	
+	int dcd_chkcount;		/* check counts to prevent */
+	int cts_chkcount;		/* too many IRQs if a signal */
+	int dsr_chkcount;		/* is floating */
+	int ri_chkcount;
+
+	char *buffer_list;		/* virtual address of Rx & Tx buffer lists */
+	unsigned long buffer_list_phys;
+
+	unsigned int rx_buffer_count;	/* count of total allocated Rx buffers */
+	DMABUFFERENTRY *rx_buffer_list;	/* list of receive buffer entries */
+	unsigned int current_rx_buffer;
+
+	int num_tx_dma_buffers;		/* number of tx dma frames required */
+ 	int tx_dma_buffers_used;
+	unsigned int tx_buffer_count;	/* count of total allocated Tx buffers */
+	DMABUFFERENTRY *tx_buffer_list;	/* list of transmit buffer entries */
+	int start_tx_dma_buffer;	/* tx dma buffer to start tx dma operation */
+	int current_tx_buffer;          /* next tx dma buffer to be loaded */
+	
+	unsigned char *intermediate_rxbuffer;
+
+	int num_tx_holding_buffers;	/* number of tx holding buffer allocated */
+	int get_tx_holding_index;  	/* next tx holding buffer for adapter to load */
+	int put_tx_holding_index;  	/* next tx holding buffer to store user request */
+	int tx_holding_count;		/* number of tx holding buffers waiting */
+	struct tx_holding_buffer tx_holding_buffers[MAX_TX_HOLDING_BUFFERS];
+
+	int rx_enabled;
+	int rx_overflow;
+	int rx_rcc_underrun;
+
+	int tx_enabled;
+	int tx_active;
+	u32 idle_mode;
+
+	u16 cmr_value;
+	u16 tcsr_value;
+
+	char device_name[25];		/* device instance name */
+
+	unsigned int bus_type;	/* expansion bus type (ISA,EISA,PCI) */
+	unsigned char bus;		/* expansion bus number (zero based) */
+	unsigned char function;		/* PCI device number */
+
+	unsigned int io_base;		/* base I/O address of adapter */
+	unsigned int io_addr_size;	/* size of the I/O address range */
+	int io_addr_requested;		/* nonzero if I/O address requested */
+	
+	unsigned int irq_level;		/* interrupt level */
+	unsigned long irq_flags;
+	int irq_requested;		/* nonzero if IRQ requested */
+	
+	unsigned int dma_level;		/* DMA channel */
+	int dma_requested;		/* nonzero if dma channel requested */
+
+	u16 mbre_bit;
+	u16 loopback_bits;
+	u16 usc_idle_mode;
+
+	MGSL_PARAMS params;		/* communications parameters */
+
+	unsigned char serial_signals;	/* current serial signal states */
+
+	int irq_occurred;		/* for diagnostics use */
+	unsigned int init_error;	/* Initialization startup error 		(DIAGS)	*/
+	int	fDiagnosticsmode;	/* Driver in Diagnostic mode?			(DIAGS)	*/
+
+	u32 last_mem_alloc;
+	unsigned char* memory_base;	/* shared memory address (PCI only) */
+	u32 phys_memory_base;
+	int shared_mem_requested;
+
+	unsigned char* lcr_base;	/* local config registers (PCI only) */
+	u32 phys_lcr_base;
+	u32 lcr_offset;
+	int lcr_mem_requested;
+
+	u32 misc_ctrl_value;
+	char flag_buf[MAX_ASYNC_BUFFER_SIZE];
+	char char_buf[MAX_ASYNC_BUFFER_SIZE];	
+	BOOLEAN drop_rts_on_tx_done;
+
+	BOOLEAN loopmode_insert_requested;
+	BOOLEAN	loopmode_send_done_requested;
+	
+	struct	_input_signal_events	input_signal_events;
+
+	/* generic HDLC device parts */
+	int netcount;
+	int dosyncppp;
+	spinlock_t netlock;
+
+#ifdef CONFIG_HDLC
+	struct net_device *netdev;
+#endif
+};
+
+#define MGSL_MAGIC 0x5401
+
+/*
+ * The size of the serial xmit buffer is 1 page, or 4096 bytes
+ */
+#ifndef SERIAL_XMIT_SIZE
+#define SERIAL_XMIT_SIZE 4096
+#endif
+
+/*
+ * These macros define the offsets used in calculating the
+ * I/O address of the specified USC registers.
+ */
+
+
+#define DCPIN 2		/* Bit 1 of I/O address */
+#define SDPIN 4		/* Bit 2 of I/O address */
+
+#define DCAR 0		/* DMA command/address register */
+#define CCAR SDPIN		/* channel command/address register */
+#define DATAREG DCPIN + SDPIN	/* serial data register */
+#define MSBONLY 0x41
+#define LSBONLY 0x40
+
+/*
+ * These macros define the register address (ordinal number)
+ * used for writing address/value pairs to the USC.
+ */
+
+#define CMR	0x02	/* Channel mode Register */
+#define CCSR	0x04	/* Channel Command/status Register */
+#define CCR	0x06	/* Channel Control Register */
+#define PSR	0x08	/* Port status Register */
+#define PCR	0x0a	/* Port Control Register */
+#define TMDR	0x0c	/* Test mode Data Register */
+#define TMCR	0x0e	/* Test mode Control Register */
+#define CMCR	0x10	/* Clock mode Control Register */
+#define HCR	0x12	/* Hardware Configuration Register */
+#define IVR	0x14	/* Interrupt Vector Register */
+#define IOCR	0x16	/* Input/Output Control Register */
+#define ICR	0x18	/* Interrupt Control Register */
+#define DCCR	0x1a	/* Daisy Chain Control Register */
+#define MISR	0x1c	/* Misc Interrupt status Register */
+#define SICR	0x1e	/* status Interrupt Control Register */
+#define RDR	0x20	/* Receive Data Register */
+#define RMR	0x22	/* Receive mode Register */
+#define RCSR	0x24	/* Receive Command/status Register */
+#define RICR	0x26	/* Receive Interrupt Control Register */
+#define RSR	0x28	/* Receive Sync Register */
+#define RCLR	0x2a	/* Receive count Limit Register */
+#define RCCR	0x2c	/* Receive Character count Register */
+#define TC0R	0x2e	/* Time Constant 0 Register */
+#define TDR	0x30	/* Transmit Data Register */
+#define TMR	0x32	/* Transmit mode Register */
+#define TCSR	0x34	/* Transmit Command/status Register */
+#define TICR	0x36	/* Transmit Interrupt Control Register */
+#define TSR	0x38	/* Transmit Sync Register */
+#define TCLR	0x3a	/* Transmit count Limit Register */
+#define TCCR	0x3c	/* Transmit Character count Register */
+#define TC1R	0x3e	/* Time Constant 1 Register */
+
+
+/*
+ * MACRO DEFINITIONS FOR DMA REGISTERS
+ */
+
+#define DCR	0x06	/* DMA Control Register (shared) */
+#define DACR	0x08	/* DMA Array count Register (shared) */
+#define BDCR	0x12	/* Burst/Dwell Control Register (shared) */
+#define DIVR	0x14	/* DMA Interrupt Vector Register (shared) */	
+#define DICR	0x18	/* DMA Interrupt Control Register (shared) */
+#define CDIR	0x1a	/* Clear DMA Interrupt Register (shared) */
+#define SDIR	0x1c	/* Set DMA Interrupt Register (shared) */
+
+#define TDMR	0x02	/* Transmit DMA mode Register */
+#define TDIAR	0x1e	/* Transmit DMA Interrupt Arm Register */
+#define TBCR	0x2a	/* Transmit Byte count Register */
+#define TARL	0x2c	/* Transmit Address Register (low) */
+#define TARU	0x2e	/* Transmit Address Register (high) */
+#define NTBCR	0x3a	/* Next Transmit Byte count Register */
+#define NTARL	0x3c	/* Next Transmit Address Register (low) */
+#define NTARU	0x3e	/* Next Transmit Address Register (high) */
+
+#define RDMR	0x82	/* Receive DMA mode Register (non-shared) */
+#define RDIAR	0x9e	/* Receive DMA Interrupt Arm Register */
+#define RBCR	0xaa	/* Receive Byte count Register */
+#define RARL	0xac	/* Receive Address Register (low) */
+#define RARU	0xae	/* Receive Address Register (high) */
+#define NRBCR	0xba	/* Next Receive Byte count Register */
+#define NRARL	0xbc	/* Next Receive Address Register (low) */
+#define NRARU	0xbe	/* Next Receive Address Register (high) */
+
+
+/*
+ * MACRO DEFINITIONS FOR MODEM STATUS BITS
+ */
+
+#define MODEMSTATUS_DTR 0x80
+#define MODEMSTATUS_DSR 0x40
+#define MODEMSTATUS_RTS 0x20
+#define MODEMSTATUS_CTS 0x10
+#define MODEMSTATUS_RI  0x04
+#define MODEMSTATUS_DCD 0x01
+
+
+/*
+ * Channel Command/Address Register (CCAR) Command Codes
+ */
+
+#define RTCmd_Null			0x0000
+#define RTCmd_ResetHighestIus		0x1000
+#define RTCmd_TriggerChannelLoadDma	0x2000
+#define RTCmd_TriggerRxDma		0x2800
+#define RTCmd_TriggerTxDma		0x3000
+#define RTCmd_TriggerRxAndTxDma		0x3800
+#define RTCmd_PurgeRxFifo		0x4800
+#define RTCmd_PurgeTxFifo		0x5000
+#define RTCmd_PurgeRxAndTxFifo		0x5800
+#define RTCmd_LoadRcc			0x6800
+#define RTCmd_LoadTcc			0x7000
+#define RTCmd_LoadRccAndTcc		0x7800
+#define RTCmd_LoadTC0			0x8800
+#define RTCmd_LoadTC1			0x9000
+#define RTCmd_LoadTC0AndTC1		0x9800
+#define RTCmd_SerialDataLSBFirst	0xa000
+#define RTCmd_SerialDataMSBFirst	0xa800
+#define RTCmd_SelectBigEndian		0xb000
+#define RTCmd_SelectLittleEndian	0xb800
+
+
+/*
+ * DMA Command/Address Register (DCAR) Command Codes
+ */
+
+#define DmaCmd_Null			0x0000
+#define DmaCmd_ResetTxChannel		0x1000
+#define DmaCmd_ResetRxChannel		0x1200
+#define DmaCmd_StartTxChannel		0x2000
+#define DmaCmd_StartRxChannel		0x2200
+#define DmaCmd_ContinueTxChannel	0x3000
+#define DmaCmd_ContinueRxChannel	0x3200
+#define DmaCmd_PauseTxChannel		0x4000
+#define DmaCmd_PauseRxChannel		0x4200
+#define DmaCmd_AbortTxChannel		0x5000
+#define DmaCmd_AbortRxChannel		0x5200
+#define DmaCmd_InitTxChannel		0x7000
+#define DmaCmd_InitRxChannel		0x7200
+#define DmaCmd_ResetHighestDmaIus	0x8000
+#define DmaCmd_ResetAllChannels		0x9000
+#define DmaCmd_StartAllChannels		0xa000
+#define DmaCmd_ContinueAllChannels	0xb000
+#define DmaCmd_PauseAllChannels		0xc000
+#define DmaCmd_AbortAllChannels		0xd000
+#define DmaCmd_InitAllChannels		0xf000
+
+#define TCmd_Null			0x0000
+#define TCmd_ClearTxCRC			0x2000
+#define TCmd_SelectTicrTtsaData		0x4000
+#define TCmd_SelectTicrTxFifostatus	0x5000
+#define TCmd_SelectTicrIntLevel		0x6000
+#define TCmd_SelectTicrdma_level		0x7000
+#define TCmd_SendFrame			0x8000
+#define TCmd_SendAbort			0x9000
+#define TCmd_EnableDleInsertion		0xc000
+#define TCmd_DisableDleInsertion	0xd000
+#define TCmd_ClearEofEom		0xe000
+#define TCmd_SetEofEom			0xf000
+
+#define RCmd_Null			0x0000
+#define RCmd_ClearRxCRC			0x2000
+#define RCmd_EnterHuntmode		0x3000
+#define RCmd_SelectRicrRtsaData		0x4000
+#define RCmd_SelectRicrRxFifostatus	0x5000
+#define RCmd_SelectRicrIntLevel		0x6000
+#define RCmd_SelectRicrdma_level		0x7000
+
+/*
+ * Bits for enabling and disabling IRQs in Interrupt Control Register (ICR)
+ */
+ 
+#define RECEIVE_STATUS		BIT5
+#define RECEIVE_DATA		BIT4
+#define TRANSMIT_STATUS		BIT3
+#define TRANSMIT_DATA		BIT2
+#define IO_PIN			BIT1
+#define MISC			BIT0
+
+
+/*
+ * Receive status Bits in Receive Command/status Register RCSR
+ */
+
+#define RXSTATUS_SHORT_FRAME		BIT8
+#define RXSTATUS_CODE_VIOLATION		BIT8
+#define RXSTATUS_EXITED_HUNT		BIT7
+#define RXSTATUS_IDLE_RECEIVED		BIT6
+#define RXSTATUS_BREAK_RECEIVED		BIT5
+#define RXSTATUS_ABORT_RECEIVED		BIT5
+#define RXSTATUS_RXBOUND		BIT4
+#define RXSTATUS_CRC_ERROR		BIT3
+#define RXSTATUS_FRAMING_ERROR		BIT3
+#define RXSTATUS_ABORT			BIT2
+#define RXSTATUS_PARITY_ERROR		BIT2
+#define RXSTATUS_OVERRUN		BIT1
+#define RXSTATUS_DATA_AVAILABLE		BIT0
+#define RXSTATUS_ALL			0x01f6
+#define usc_UnlatchRxstatusBits(a,b) usc_OutReg( (a), RCSR, (u16)((b) & RXSTATUS_ALL) )
+
+/*
+ * Values for setting transmit idle mode in 
+ * Transmit Control/status Register (TCSR)
+ */
+#define IDLEMODE_FLAGS			0x0000
+#define IDLEMODE_ALT_ONE_ZERO		0x0100
+#define IDLEMODE_ZERO			0x0200
+#define IDLEMODE_ONE			0x0300
+#define IDLEMODE_ALT_MARK_SPACE		0x0500
+#define IDLEMODE_SPACE			0x0600
+#define IDLEMODE_MARK			0x0700
+#define IDLEMODE_MASK			0x0700
+
+/*
+ * IUSC revision identifiers
+ */
+#define	IUSC_SL1660			0x4d44
+#define IUSC_PRE_SL1660			0x4553
+
+/*
+ * Transmit status Bits in Transmit Command/status Register (TCSR)
+ */
+
+#define TCSR_PRESERVE			0x0F00
+
+#define TCSR_UNDERWAIT			BIT11
+#define TXSTATUS_PREAMBLE_SENT		BIT7
+#define TXSTATUS_IDLE_SENT		BIT6
+#define TXSTATUS_ABORT_SENT		BIT5
+#define TXSTATUS_EOF_SENT		BIT4
+#define TXSTATUS_EOM_SENT		BIT4
+#define TXSTATUS_CRC_SENT		BIT3
+#define TXSTATUS_ALL_SENT		BIT2
+#define TXSTATUS_UNDERRUN		BIT1
+#define TXSTATUS_FIFO_EMPTY		BIT0
+#define TXSTATUS_ALL			0x00fa
+#define usc_UnlatchTxstatusBits(a,b) usc_OutReg( (a), TCSR, (u16)((a)->tcsr_value + ((b) & 0x00FF)) )
+				
+
+#define MISCSTATUS_RXC_LATCHED		BIT15
+#define MISCSTATUS_RXC			BIT14
+#define MISCSTATUS_TXC_LATCHED		BIT13
+#define MISCSTATUS_TXC			BIT12
+#define MISCSTATUS_RI_LATCHED		BIT11
+#define MISCSTATUS_RI			BIT10
+#define MISCSTATUS_DSR_LATCHED		BIT9
+#define MISCSTATUS_DSR			BIT8
+#define MISCSTATUS_DCD_LATCHED		BIT7
+#define MISCSTATUS_DCD			BIT6
+#define MISCSTATUS_CTS_LATCHED		BIT5
+#define MISCSTATUS_CTS			BIT4
+#define MISCSTATUS_RCC_UNDERRUN		BIT3
+#define MISCSTATUS_DPLL_NO_SYNC		BIT2
+#define MISCSTATUS_BRG1_ZERO		BIT1
+#define MISCSTATUS_BRG0_ZERO		BIT0
+
+#define usc_UnlatchIostatusBits(a,b) usc_OutReg((a),MISR,(u16)((b) & 0xaaa0))
+#define usc_UnlatchMiscstatusBits(a,b) usc_OutReg((a),MISR,(u16)((b) & 0x000f))
+
+#define SICR_RXC_ACTIVE			BIT15
+#define SICR_RXC_INACTIVE		BIT14
+#define SICR_RXC			(BIT15+BIT14)
+#define SICR_TXC_ACTIVE			BIT13
+#define SICR_TXC_INACTIVE		BIT12
+#define SICR_TXC			(BIT13+BIT12)
+#define SICR_RI_ACTIVE			BIT11
+#define SICR_RI_INACTIVE		BIT10
+#define SICR_RI				(BIT11+BIT10)
+#define SICR_DSR_ACTIVE			BIT9
+#define SICR_DSR_INACTIVE		BIT8
+#define SICR_DSR			(BIT9+BIT8)
+#define SICR_DCD_ACTIVE			BIT7
+#define SICR_DCD_INACTIVE		BIT6
+#define SICR_DCD			(BIT7+BIT6)
+#define SICR_CTS_ACTIVE			BIT5
+#define SICR_CTS_INACTIVE		BIT4
+#define SICR_CTS			(BIT5+BIT4)
+#define SICR_RCC_UNDERFLOW		BIT3
+#define SICR_DPLL_NO_SYNC		BIT2
+#define SICR_BRG1_ZERO			BIT1
+#define SICR_BRG0_ZERO			BIT0
+
+void usc_DisableMasterIrqBit( struct mgsl_struct *info );
+void usc_EnableMasterIrqBit( struct mgsl_struct *info );
+void usc_EnableInterrupts( struct mgsl_struct *info, u16 IrqMask );
+void usc_DisableInterrupts( struct mgsl_struct *info, u16 IrqMask );
+void usc_ClearIrqPendingBits( struct mgsl_struct *info, u16 IrqMask );
+
+#define usc_EnableInterrupts( a, b ) \
+	usc_OutReg( (a), ICR, (u16)((usc_InReg((a),ICR) & 0xff00) + 0xc0 + (b)) )
+
+#define usc_DisableInterrupts( a, b ) \
+	usc_OutReg( (a), ICR, (u16)((usc_InReg((a),ICR) & 0xff00) + 0x80 + (b)) )
+
+#define usc_EnableMasterIrqBit(a) \
+	usc_OutReg( (a), ICR, (u16)((usc_InReg((a),ICR) & 0x0f00) + 0xb000) )
+
+#define usc_DisableMasterIrqBit(a) \
+	usc_OutReg( (a), ICR, (u16)(usc_InReg((a),ICR) & 0x7f00) )
+
+#define usc_ClearIrqPendingBits( a, b ) usc_OutReg( (a), DCCR, 0x40 + (b) )
+
+/*
+ * Transmit status Bits in Transmit Control status Register (TCSR)
+ * and Transmit Interrupt Control Register (TICR) (except BIT2, BIT0)
+ */
+
+#define TXSTATUS_PREAMBLE_SENT	BIT7
+#define TXSTATUS_IDLE_SENT	BIT6
+#define TXSTATUS_ABORT_SENT	BIT5
+#define TXSTATUS_EOF		BIT4
+#define TXSTATUS_CRC_SENT	BIT3
+#define TXSTATUS_ALL_SENT	BIT2
+#define TXSTATUS_UNDERRUN	BIT1
+#define TXSTATUS_FIFO_EMPTY	BIT0
+
+#define DICR_MASTER		BIT15
+#define DICR_TRANSMIT		BIT0
+#define DICR_RECEIVE		BIT1
+
+#define usc_EnableDmaInterrupts(a,b) \
+	usc_OutDmaReg( (a), DICR, (u16)(usc_InDmaReg((a),DICR) | (b)) )
+
+#define usc_DisableDmaInterrupts(a,b) \
+	usc_OutDmaReg( (a), DICR, (u16)(usc_InDmaReg((a),DICR) & ~(b)) )
+
+#define usc_EnableStatusIrqs(a,b) \
+	usc_OutReg( (a), SICR, (u16)(usc_InReg((a),SICR) | (b)) )
+
+#define usc_DisablestatusIrqs(a,b) \
+	usc_OutReg( (a), SICR, (u16)(usc_InReg((a),SICR) & ~(b)) )
+
+/* Transmit status Bits in Transmit Control status Register (TCSR) */
+/* and Transmit Interrupt Control Register (TICR) (except BIT2, BIT0) */
+
+
+#define DISABLE_UNCONDITIONAL    0
+#define DISABLE_END_OF_FRAME     1
+#define ENABLE_UNCONDITIONAL     2
+#define ENABLE_AUTO_CTS          3
+#define ENABLE_AUTO_DCD          3
+#define usc_EnableTransmitter(a,b) \
+	usc_OutReg( (a), TMR, (u16)((usc_InReg((a),TMR) & 0xfffc) | (b)) )
+#define usc_EnableReceiver(a,b) \
+	usc_OutReg( (a), RMR, (u16)((usc_InReg((a),RMR) & 0xfffc) | (b)) )
+
+static u16  usc_InDmaReg( struct mgsl_struct *info, u16 Port );
+static void usc_OutDmaReg( struct mgsl_struct *info, u16 Port, u16 Value );
+static void usc_DmaCmd( struct mgsl_struct *info, u16 Cmd );
+
+static u16  usc_InReg( struct mgsl_struct *info, u16 Port );
+static void usc_OutReg( struct mgsl_struct *info, u16 Port, u16 Value );
+static void usc_RTCmd( struct mgsl_struct *info, u16 Cmd );
+void usc_RCmd( struct mgsl_struct *info, u16 Cmd );
+void usc_TCmd( struct mgsl_struct *info, u16 Cmd );
+
+#define usc_TCmd(a,b) usc_OutReg((a), TCSR, (u16)((a)->tcsr_value + (b)))
+#define usc_RCmd(a,b) usc_OutReg((a), RCSR, (b))
+
+#define usc_SetTransmitSyncChars(a,s0,s1) usc_OutReg((a), TSR, (u16)(((u16)s0<<8)|(u16)s1))
+
+static void usc_process_rxoverrun_sync( struct mgsl_struct *info );
+static void usc_start_receiver( struct mgsl_struct *info );
+static void usc_stop_receiver( struct mgsl_struct *info );
+
+static void usc_start_transmitter( struct mgsl_struct *info );
+static void usc_stop_transmitter( struct mgsl_struct *info );
+static void usc_set_txidle( struct mgsl_struct *info );
+static void usc_load_txfifo( struct mgsl_struct *info );
+
+static void usc_enable_aux_clock( struct mgsl_struct *info, u32 DataRate );
+static void usc_enable_loopback( struct mgsl_struct *info, int enable );
+
+static void usc_get_serial_signals( struct mgsl_struct *info );
+static void usc_set_serial_signals( struct mgsl_struct *info );
+
+static void usc_reset( struct mgsl_struct *info );
+
+static void usc_set_sync_mode( struct mgsl_struct *info );
+static void usc_set_sdlc_mode( struct mgsl_struct *info );
+static void usc_set_async_mode( struct mgsl_struct *info );
+static void usc_enable_async_clock( struct mgsl_struct *info, u32 DataRate );
+
+static void usc_loopback_frame( struct mgsl_struct *info );
+
+static void mgsl_tx_timeout(unsigned long context);
+
+
+static void usc_loopmode_cancel_transmit( struct mgsl_struct * info );
+static void usc_loopmode_insert_request( struct mgsl_struct * info );
+static int usc_loopmode_active( struct mgsl_struct * info);
+static void usc_loopmode_send_done( struct mgsl_struct * info );
+
+static int mgsl_ioctl_common(struct mgsl_struct *info, unsigned int cmd, unsigned long arg);
+
+#ifdef CONFIG_HDLC
+#define dev_to_port(D) (dev_to_hdlc(D)->priv)
+static void hdlcdev_tx_done(struct mgsl_struct *info);
+static void hdlcdev_rx(struct mgsl_struct *info, char *buf, int size);
+static int  hdlcdev_init(struct mgsl_struct *info);
+static void hdlcdev_exit(struct mgsl_struct *info);
+#endif
+
+/*
+ * Defines a BUS descriptor value for the PCI adapter
+ * local bus address ranges.
+ */
+
+#define BUS_DESCRIPTOR( WrHold, WrDly, RdDly, Nwdd, Nwad, Nxda, Nrdd, Nrad ) \
+(0x00400020 + \
+((WrHold) << 30) + \
+((WrDly)  << 28) + \
+((RdDly)  << 26) + \
+((Nwdd)   << 20) + \
+((Nwad)   << 15) + \
+((Nxda)   << 13) + \
+((Nrdd)   << 11) + \
+((Nrad)   <<  6) )
+
+static void mgsl_trace_block(struct mgsl_struct *info,const char* data, int count, int xmit);
+
+/*
+ * Adapter diagnostic routines
+ */
+static BOOLEAN mgsl_register_test( struct mgsl_struct *info );
+static BOOLEAN mgsl_irq_test( struct mgsl_struct *info );
+static BOOLEAN mgsl_dma_test( struct mgsl_struct *info );
+static BOOLEAN mgsl_memory_test( struct mgsl_struct *info );
+static int mgsl_adapter_test( struct mgsl_struct *info );
+
+/*
+ * device and resource management routines
+ */
+static int mgsl_claim_resources(struct mgsl_struct *info);
+static void mgsl_release_resources(struct mgsl_struct *info);
+static void mgsl_add_device(struct mgsl_struct *info);
+static struct mgsl_struct* mgsl_allocate_device(void);
+
+/*
+ * DMA buffer manupulation functions.
+ */
+static void mgsl_free_rx_frame_buffers( struct mgsl_struct *info, unsigned int StartIndex, unsigned int EndIndex );
+static int  mgsl_get_rx_frame( struct mgsl_struct *info );
+static int  mgsl_get_raw_rx_frame( struct mgsl_struct *info );
+static void mgsl_reset_rx_dma_buffers( struct mgsl_struct *info );
+static void mgsl_reset_tx_dma_buffers( struct mgsl_struct *info );
+static int num_free_tx_dma_buffers(struct mgsl_struct *info);
+static void mgsl_load_tx_dma_buffer( struct mgsl_struct *info, const char *Buffer, unsigned int BufferSize);
+static void mgsl_load_pci_memory(char* TargetPtr, const char* SourcePtr, unsigned short count);
+
+/*
+ * DMA and Shared Memory buffer allocation and formatting
+ */
+static int  mgsl_allocate_dma_buffers(struct mgsl_struct *info);
+static void mgsl_free_dma_buffers(struct mgsl_struct *info);
+static int  mgsl_alloc_frame_memory(struct mgsl_struct *info, DMABUFFERENTRY *BufferList,int Buffercount);
+static void mgsl_free_frame_memory(struct mgsl_struct *info, DMABUFFERENTRY *BufferList,int Buffercount);
+static int  mgsl_alloc_buffer_list_memory(struct mgsl_struct *info);
+static void mgsl_free_buffer_list_memory(struct mgsl_struct *info);
+static int mgsl_alloc_intermediate_rxbuffer_memory(struct mgsl_struct *info);
+static void mgsl_free_intermediate_rxbuffer_memory(struct mgsl_struct *info);
+static int mgsl_alloc_intermediate_txbuffer_memory(struct mgsl_struct *info);
+static void mgsl_free_intermediate_txbuffer_memory(struct mgsl_struct *info);
+static int load_next_tx_holding_buffer(struct mgsl_struct *info);
+static int save_tx_buffer_request(struct mgsl_struct *info,const char *Buffer, unsigned int BufferSize);
+
+/*
+ * Bottom half interrupt handlers
+ */
+static void mgsl_bh_handler(void* Context);
+static void mgsl_bh_receive(struct mgsl_struct *info);
+static void mgsl_bh_transmit(struct mgsl_struct *info);
+static void mgsl_bh_status(struct mgsl_struct *info);
+
+/*
+ * Interrupt handler routines and dispatch table.
+ */
+static void mgsl_isr_null( struct mgsl_struct *info );
+static void mgsl_isr_transmit_data( struct mgsl_struct *info );
+static void mgsl_isr_receive_data( struct mgsl_struct *info );
+static void mgsl_isr_receive_status( struct mgsl_struct *info );
+static void mgsl_isr_transmit_status( struct mgsl_struct *info );
+static void mgsl_isr_io_pin( struct mgsl_struct *info );
+static void mgsl_isr_misc( struct mgsl_struct *info );
+static void mgsl_isr_receive_dma( struct mgsl_struct *info );
+static void mgsl_isr_transmit_dma( struct mgsl_struct *info );
+
+typedef void (*isr_dispatch_func)(struct mgsl_struct *);
+
+static isr_dispatch_func UscIsrTable[7] =
+{
+	mgsl_isr_null,
+	mgsl_isr_misc,
+	mgsl_isr_io_pin,
+	mgsl_isr_transmit_data,
+	mgsl_isr_transmit_status,
+	mgsl_isr_receive_data,
+	mgsl_isr_receive_status
+};
+
+/*
+ * ioctl call handlers
+ */
+static int tiocmget(struct tty_struct *tty, struct file *file);
+static int tiocmset(struct tty_struct *tty, struct file *file,
+		    unsigned int set, unsigned int clear);
+static int mgsl_get_stats(struct mgsl_struct * info, struct mgsl_icount
+	__user *user_icount);
+static int mgsl_get_params(struct mgsl_struct * info, MGSL_PARAMS  __user *user_params);
+static int mgsl_set_params(struct mgsl_struct * info, MGSL_PARAMS  __user *new_params);
+static int mgsl_get_txidle(struct mgsl_struct * info, int __user *idle_mode);
+static int mgsl_set_txidle(struct mgsl_struct * info, int idle_mode);
+static int mgsl_txenable(struct mgsl_struct * info, int enable);
+static int mgsl_txabort(struct mgsl_struct * info);
+static int mgsl_rxenable(struct mgsl_struct * info, int enable);
+static int mgsl_wait_event(struct mgsl_struct * info, int __user *mask);
+static int mgsl_loopmode_send_done( struct mgsl_struct * info );
+
+/* set non-zero on successful registration with PCI subsystem */
+static int pci_registered;
+
+/*
+ * Global linked list of SyncLink devices
+ */
+static struct mgsl_struct *mgsl_device_list;
+static int mgsl_device_count;
+
+/*
+ * Set this param to non-zero to load eax with the
+ * .text section address and breakpoint on module load.
+ * This is useful for use with gdb and add-symbol-file command.
+ */
+static int break_on_load;
+
+/*
+ * Driver major number, defaults to zero to get auto
+ * assigned major number. May be forced as module parameter.
+ */
+static int ttymajor;
+
+/*
+ * Array of user specified options for ISA adapters.
+ */
+static int io[MAX_ISA_DEVICES];
+static int irq[MAX_ISA_DEVICES];
+static int dma[MAX_ISA_DEVICES];
+static int debug_level;
+static int maxframe[MAX_TOTAL_DEVICES];
+static int dosyncppp[MAX_TOTAL_DEVICES];
+static int txdmabufs[MAX_TOTAL_DEVICES];
+static int txholdbufs[MAX_TOTAL_DEVICES];
+	
+module_param(break_on_load, bool, 0);
+module_param(ttymajor, int, 0);
+module_param_array(io, int, NULL, 0);
+module_param_array(irq, int, NULL, 0);
+module_param_array(dma, int, NULL, 0);
+module_param(debug_level, int, 0);
+module_param_array(maxframe, int, NULL, 0);
+module_param_array(dosyncppp, int, NULL, 0);
+module_param_array(txdmabufs, int, NULL, 0);
+module_param_array(txholdbufs, int, NULL, 0);
+
+static char *driver_name = "SyncLink serial driver";
+static char *driver_version = "$Revision: 4.28 $";
+
+static int synclink_init_one (struct pci_dev *dev,
+				     const struct pci_device_id *ent);
+static void synclink_remove_one (struct pci_dev *dev);
+
+static struct pci_device_id synclink_pci_tbl[] = {
+	{ PCI_VENDOR_ID_MICROGATE, PCI_DEVICE_ID_MICROGATE_USC, PCI_ANY_ID, PCI_ANY_ID, },
+	{ PCI_VENDOR_ID_MICROGATE, 0x0210, PCI_ANY_ID, PCI_ANY_ID, },
+	{ 0, }, /* terminate list */
+};
+MODULE_DEVICE_TABLE(pci, synclink_pci_tbl);
+
+MODULE_LICENSE("GPL");
+
+static struct pci_driver synclink_pci_driver = {
+	.name		= "synclink",
+	.id_table	= synclink_pci_tbl,
+	.probe		= synclink_init_one,
+	.remove		= __devexit_p(synclink_remove_one),
+};
+
+static struct tty_driver *serial_driver;
+
+/* number of characters left in xmit buffer before we ask for more */
+#define WAKEUP_CHARS 256
+
+
+static void mgsl_change_params(struct mgsl_struct *info);
+static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout);
+
+/*
+ * 1st function defined in .text section. Calling this function in
+ * init_module() followed by a breakpoint allows a remote debugger
+ * (gdb) to get the .text address for the add-symbol-file command.
+ * This allows remote debugging of dynamically loadable modules.
+ */
+static void* mgsl_get_text_ptr(void)
+{
+	return mgsl_get_text_ptr;
+}
+
+/*
+ * tmp_buf is used as a temporary buffer by mgsl_write.  We need to
+ * lock it in case the COPY_FROM_USER blocks while swapping in a page,
+ * and some other program tries to do a serial write at the same time.
+ * Since the lock will only come under contention when the system is
+ * swapping and available memory is low, it makes sense to share one
+ * buffer across all the serial ioports, since it significantly saves
+ * memory if large numbers of serial ports are open.
+ */
+static unsigned char *tmp_buf;
+static DECLARE_MUTEX(tmp_buf_sem);
+
+static inline int mgsl_paranoia_check(struct mgsl_struct *info,
+					char *name, const char *routine)
+{
+#ifdef MGSL_PARANOIA_CHECK
+	static const char *badmagic =
+		"Warning: bad magic number for mgsl struct (%s) in %s\n";
+	static const char *badinfo =
+		"Warning: null mgsl_struct for (%s) in %s\n";
+
+	if (!info) {
+		printk(badinfo, name, routine);
+		return 1;
+	}
+	if (info->magic != MGSL_MAGIC) {
+		printk(badmagic, name, routine);
+		return 1;
+	}
+#else
+	if (!info)
+		return 1;
+#endif
+	return 0;
+}
+
+/**
+ * line discipline callback wrappers
+ *
+ * The wrappers maintain line discipline references
+ * while calling into the line discipline.
+ *
+ * ldisc_receive_buf  - pass receive data to line discipline
+ */
+
+static void ldisc_receive_buf(struct tty_struct *tty,
+			      const __u8 *data, char *flags, int count)
+{
+	struct tty_ldisc *ld;
+	if (!tty)
+		return;
+	ld = tty_ldisc_ref(tty);
+	if (ld) {
+		if (ld->receive_buf)
+			ld->receive_buf(tty, data, flags, count);
+		tty_ldisc_deref(ld);
+	}
+}
+
+/* mgsl_stop()		throttle (stop) transmitter
+ * 	
+ * Arguments:		tty	pointer to tty info structure
+ * Return Value:	None
+ */
+static void mgsl_stop(struct tty_struct *tty)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_stop"))
+		return;
+	
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk("mgsl_stop(%s)\n",info->device_name);	
+		
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	if (info->tx_enabled)
+	 	usc_stop_transmitter(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+}	/* end of mgsl_stop() */
+
+/* mgsl_start()		release (start) transmitter
+ * 	
+ * Arguments:		tty	pointer to tty info structure
+ * Return Value:	None
+ */
+static void mgsl_start(struct tty_struct *tty)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_start"))
+		return;
+	
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk("mgsl_start(%s)\n",info->device_name);	
+		
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	if (!info->tx_enabled)
+	 	usc_start_transmitter(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+}	/* end of mgsl_start() */
+
+/*
+ * Bottom half work queue access functions
+ */
+
+/* mgsl_bh_action()	Return next bottom half action to perform.
+ * Return Value:	BH action code or 0 if nothing to do.
+ */
+static int mgsl_bh_action(struct mgsl_struct *info)
+{
+	unsigned long flags;
+	int rc = 0;
+	
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+
+	if (info->pending_bh & BH_RECEIVE) {
+		info->pending_bh &= ~BH_RECEIVE;
+		rc = BH_RECEIVE;
+	} else if (info->pending_bh & BH_TRANSMIT) {
+		info->pending_bh &= ~BH_TRANSMIT;
+		rc = BH_TRANSMIT;
+	} else if (info->pending_bh & BH_STATUS) {
+		info->pending_bh &= ~BH_STATUS;
+		rc = BH_STATUS;
+	}
+
+	if (!rc) {
+		/* Mark BH routine as complete */
+		info->bh_running   = 0;
+		info->bh_requested = 0;
+	}
+	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+	return rc;
+}
+
+/*
+ * 	Perform bottom half processing of work items queued by ISR.
+ */
+static void mgsl_bh_handler(void* Context)
+{
+	struct mgsl_struct *info = (struct mgsl_struct*)Context;
+	int action;
+
+	if (!info)
+		return;
+		
+	if ( debug_level >= DEBUG_LEVEL_BH )
+		printk( "%s(%d):mgsl_bh_handler(%s) entry\n",
+			__FILE__,__LINE__,info->device_name);
+	
+	info->bh_running = 1;
+
+	while((action = mgsl_bh_action(info)) != 0) {
+	
+		/* Process work item */
+		if ( debug_level >= DEBUG_LEVEL_BH )
+			printk( "%s(%d):mgsl_bh_handler() work item action=%d\n",
+				__FILE__,__LINE__,action);
+
+		switch (action) {
+		
+		case BH_RECEIVE:
+			mgsl_bh_receive(info);
+			break;
+		case BH_TRANSMIT:
+			mgsl_bh_transmit(info);
+			break;
+		case BH_STATUS:
+			mgsl_bh_status(info);
+			break;
+		default:
+			/* unknown work item ID */
+			printk("Unknown work item ID=%08X!\n", action);
+			break;
+		}
+	}
+
+	if ( debug_level >= DEBUG_LEVEL_BH )
+		printk( "%s(%d):mgsl_bh_handler(%s) exit\n",
+			__FILE__,__LINE__,info->device_name);
+}
+
+static void mgsl_bh_receive(struct mgsl_struct *info)
+{
+	int (*get_rx_frame)(struct mgsl_struct *info) =
+		(info->params.mode == MGSL_MODE_HDLC ? mgsl_get_rx_frame : mgsl_get_raw_rx_frame);
+
+	if ( debug_level >= DEBUG_LEVEL_BH )
+		printk( "%s(%d):mgsl_bh_receive(%s)\n",
+			__FILE__,__LINE__,info->device_name);
+	
+	do
+	{
+		if (info->rx_rcc_underrun) {
+			unsigned long flags;
+			spin_lock_irqsave(&info->irq_spinlock,flags);
+			usc_start_receiver(info);
+			spin_unlock_irqrestore(&info->irq_spinlock,flags);
+			return;
+		}
+	} while(get_rx_frame(info));
+}
+
+static void mgsl_bh_transmit(struct mgsl_struct *info)
+{
+	struct tty_struct *tty = info->tty;
+	unsigned long flags;
+	
+	if ( debug_level >= DEBUG_LEVEL_BH )
+		printk( "%s(%d):mgsl_bh_transmit() entry on %s\n",
+			__FILE__,__LINE__,info->device_name);
+
+	if (tty) {
+		tty_wakeup(tty);
+		wake_up_interruptible(&tty->write_wait);
+	}
+
+	/* if transmitter idle and loopmode_send_done_requested
+	 * then start echoing RxD to TxD
+	 */
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+ 	if ( !info->tx_active && info->loopmode_send_done_requested )
+ 		usc_loopmode_send_done( info );
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+}
+
+static void mgsl_bh_status(struct mgsl_struct *info)
+{
+	if ( debug_level >= DEBUG_LEVEL_BH )
+		printk( "%s(%d):mgsl_bh_status() entry on %s\n",
+			__FILE__,__LINE__,info->device_name);
+
+	info->ri_chkcount = 0;
+	info->dsr_chkcount = 0;
+	info->dcd_chkcount = 0;
+	info->cts_chkcount = 0;
+}
+
+/* mgsl_isr_receive_status()
+ * 
+ *	Service a receive status interrupt. The type of status
+ *	interrupt is indicated by the state of the RCSR.
+ *	This is only used for HDLC mode.
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_isr_receive_status( struct mgsl_struct *info )
+{
+	u16 status = usc_InReg( info, RCSR );
+
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_isr_receive_status status=%04X\n",
+			__FILE__,__LINE__,status);
+			
+ 	if ( (status & RXSTATUS_ABORT_RECEIVED) && 
+		info->loopmode_insert_requested &&
+ 		usc_loopmode_active(info) )
+ 	{
+		++info->icount.rxabort;
+	 	info->loopmode_insert_requested = FALSE;
+ 
+ 		/* clear CMR:13 to start echoing RxD to TxD */
+		info->cmr_value &= ~BIT13;
+ 		usc_OutReg(info, CMR, info->cmr_value);
+ 
+		/* disable received abort irq (no longer required) */
+	 	usc_OutReg(info, RICR,
+ 			(usc_InReg(info, RICR) & ~RXSTATUS_ABORT_RECEIVED));
+ 	}
+
+	if (status & (RXSTATUS_EXITED_HUNT + RXSTATUS_IDLE_RECEIVED)) {
+		if (status & RXSTATUS_EXITED_HUNT)
+			info->icount.exithunt++;
+		if (status & RXSTATUS_IDLE_RECEIVED)
+			info->icount.rxidle++;
+		wake_up_interruptible(&info->event_wait_q);
+	}
+
+	if (status & RXSTATUS_OVERRUN){
+		info->icount.rxover++;
+		usc_process_rxoverrun_sync( info );
+	}
+
+	usc_ClearIrqPendingBits( info, RECEIVE_STATUS );
+	usc_UnlatchRxstatusBits( info, status );
+
+}	/* end of mgsl_isr_receive_status() */
+
+/* mgsl_isr_transmit_status()
+ * 
+ * 	Service a transmit status interrupt
+ *	HDLC mode :end of transmit frame
+ *	Async mode:all data is sent
+ * 	transmit status is indicated by bits in the TCSR.
+ * 
+ * Arguments:		info	       pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_isr_transmit_status( struct mgsl_struct *info )
+{
+	u16 status = usc_InReg( info, TCSR );
+
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_isr_transmit_status status=%04X\n",
+			__FILE__,__LINE__,status);
+	
+	usc_ClearIrqPendingBits( info, TRANSMIT_STATUS );
+	usc_UnlatchTxstatusBits( info, status );
+	
+	if ( status & (TXSTATUS_UNDERRUN | TXSTATUS_ABORT_SENT) )
+	{
+		/* finished sending HDLC abort. This may leave	*/
+		/* the TxFifo with data from the aborted frame	*/
+		/* so purge the TxFifo. Also shutdown the DMA	*/
+		/* channel in case there is data remaining in 	*/
+		/* the DMA buffer				*/
+ 		usc_DmaCmd( info, DmaCmd_ResetTxChannel );
+ 		usc_RTCmd( info, RTCmd_PurgeTxFifo );
+	}
+ 
+	if ( status & TXSTATUS_EOF_SENT )
+		info->icount.txok++;
+	else if ( status & TXSTATUS_UNDERRUN )
+		info->icount.txunder++;
+	else if ( status & TXSTATUS_ABORT_SENT )
+		info->icount.txabort++;
+	else
+		info->icount.txunder++;
+			
+	info->tx_active = 0;
+	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+	del_timer(&info->tx_timer);	
+	
+	if ( info->drop_rts_on_tx_done ) {
+		usc_get_serial_signals( info );
+		if ( info->serial_signals & SerialSignal_RTS ) {
+			info->serial_signals &= ~SerialSignal_RTS;
+			usc_set_serial_signals( info );
+		}
+		info->drop_rts_on_tx_done = 0;
+	}
+
+#ifdef CONFIG_HDLC
+	if (info->netcount)
+		hdlcdev_tx_done(info);
+	else 
+#endif
+	{
+		if (info->tty->stopped || info->tty->hw_stopped) {
+			usc_stop_transmitter(info);
+			return;
+		}
+		info->pending_bh |= BH_TRANSMIT;
+	}
+
+}	/* end of mgsl_isr_transmit_status() */
+
+/* mgsl_isr_io_pin()
+ * 
+ * 	Service an Input/Output pin interrupt. The type of
+ * 	interrupt is indicated by bits in the MISR
+ * 	
+ * Arguments:		info	       pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_isr_io_pin( struct mgsl_struct *info )
+{
+ 	struct	mgsl_icount *icount;
+	u16 status = usc_InReg( info, MISR );
+
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_isr_io_pin status=%04X\n",
+			__FILE__,__LINE__,status);
+			
+	usc_ClearIrqPendingBits( info, IO_PIN );
+	usc_UnlatchIostatusBits( info, status );
+
+	if (status & (MISCSTATUS_CTS_LATCHED | MISCSTATUS_DCD_LATCHED |
+	              MISCSTATUS_DSR_LATCHED | MISCSTATUS_RI_LATCHED) ) {
+		icount = &info->icount;
+		/* update input line counters */
+		if (status & MISCSTATUS_RI_LATCHED) {
+			if ((info->ri_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
+				usc_DisablestatusIrqs(info,SICR_RI);
+			icount->rng++;
+			if ( status & MISCSTATUS_RI )
+				info->input_signal_events.ri_up++;	
+			else
+				info->input_signal_events.ri_down++;	
+		}
+		if (status & MISCSTATUS_DSR_LATCHED) {
+			if ((info->dsr_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
+				usc_DisablestatusIrqs(info,SICR_DSR);
+			icount->dsr++;
+			if ( status & MISCSTATUS_DSR )
+				info->input_signal_events.dsr_up++;
+			else
+				info->input_signal_events.dsr_down++;
+		}
+		if (status & MISCSTATUS_DCD_LATCHED) {
+			if ((info->dcd_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
+				usc_DisablestatusIrqs(info,SICR_DCD);
+			icount->dcd++;
+			if (status & MISCSTATUS_DCD) {
+				info->input_signal_events.dcd_up++;
+			} else
+				info->input_signal_events.dcd_down++;
+#ifdef CONFIG_HDLC
+			if (info->netcount)
+				hdlc_set_carrier(status & MISCSTATUS_DCD, info->netdev);
+#endif
+		}
+		if (status & MISCSTATUS_CTS_LATCHED)
+		{
+			if ((info->cts_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
+				usc_DisablestatusIrqs(info,SICR_CTS);
+			icount->cts++;
+			if ( status & MISCSTATUS_CTS )
+				info->input_signal_events.cts_up++;
+			else
+				info->input_signal_events.cts_down++;
+		}
+		wake_up_interruptible(&info->status_event_wait_q);
+		wake_up_interruptible(&info->event_wait_q);
+
+		if ( (info->flags & ASYNC_CHECK_CD) && 
+		     (status & MISCSTATUS_DCD_LATCHED) ) {
+			if ( debug_level >= DEBUG_LEVEL_ISR )
+				printk("%s CD now %s...", info->device_name,
+				       (status & MISCSTATUS_DCD) ? "on" : "off");
+			if (status & MISCSTATUS_DCD)
+				wake_up_interruptible(&info->open_wait);
+			else {
+				if ( debug_level >= DEBUG_LEVEL_ISR )
+					printk("doing serial hangup...");
+				if (info->tty)
+					tty_hangup(info->tty);
+			}
+		}
+	
+		if ( (info->flags & ASYNC_CTS_FLOW) && 
+		     (status & MISCSTATUS_CTS_LATCHED) ) {
+			if (info->tty->hw_stopped) {
+				if (status & MISCSTATUS_CTS) {
+					if ( debug_level >= DEBUG_LEVEL_ISR )
+						printk("CTS tx start...");
+					if (info->tty)
+						info->tty->hw_stopped = 0;
+					usc_start_transmitter(info);
+					info->pending_bh |= BH_TRANSMIT;
+					return;
+				}
+			} else {
+				if (!(status & MISCSTATUS_CTS)) {
+					if ( debug_level >= DEBUG_LEVEL_ISR )
+						printk("CTS tx stop...");
+					if (info->tty)
+						info->tty->hw_stopped = 1;
+					usc_stop_transmitter(info);
+				}
+			}
+		}
+	}
+
+	info->pending_bh |= BH_STATUS;
+	
+	/* for diagnostics set IRQ flag */
+	if ( status & MISCSTATUS_TXC_LATCHED ){
+		usc_OutReg( info, SICR,
+			(unsigned short)(usc_InReg(info,SICR) & ~(SICR_TXC_ACTIVE+SICR_TXC_INACTIVE)) );
+		usc_UnlatchIostatusBits( info, MISCSTATUS_TXC_LATCHED );
+		info->irq_occurred = 1;
+	}
+
+}	/* end of mgsl_isr_io_pin() */
+
+/* mgsl_isr_transmit_data()
+ * 
+ * 	Service a transmit data interrupt (async mode only).
+ * 
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_isr_transmit_data( struct mgsl_struct *info )
+{
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_isr_transmit_data xmit_cnt=%d\n",
+			__FILE__,__LINE__,info->xmit_cnt);
+			
+	usc_ClearIrqPendingBits( info, TRANSMIT_DATA );
+	
+	if (info->tty->stopped || info->tty->hw_stopped) {
+		usc_stop_transmitter(info);
+		return;
+	}
+	
+	if ( info->xmit_cnt )
+		usc_load_txfifo( info );
+	else
+		info->tx_active = 0;
+		
+	if (info->xmit_cnt < WAKEUP_CHARS)
+		info->pending_bh |= BH_TRANSMIT;
+
+}	/* end of mgsl_isr_transmit_data() */
+
+/* mgsl_isr_receive_data()
+ * 
+ * 	Service a receive data interrupt. This occurs
+ * 	when operating in asynchronous interrupt transfer mode.
+ *	The receive data FIFO is flushed to the receive data buffers. 
+ * 
+ * Arguments:		info		pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_isr_receive_data( struct mgsl_struct *info )
+{
+	int Fifocount;
+	u16 status;
+	unsigned char DataByte;
+ 	struct tty_struct *tty = info->tty;
+ 	struct	mgsl_icount *icount = &info->icount;
+	
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_isr_receive_data\n",
+			__FILE__,__LINE__);
+
+	usc_ClearIrqPendingBits( info, RECEIVE_DATA );
+	
+	/* select FIFO status for RICR readback */
+	usc_RCmd( info, RCmd_SelectRicrRxFifostatus );
+
+	/* clear the Wordstatus bit so that status readback */
+	/* only reflects the status of this byte */
+	usc_OutReg( info, RICR+LSBONLY, (u16)(usc_InReg(info, RICR+LSBONLY) & ~BIT3 ));
+
+	/* flush the receive FIFO */
+
+	while( (Fifocount = (usc_InReg(info,RICR) >> 8)) ) {
+		/* read one byte from RxFIFO */
+		outw( (inw(info->io_base + CCAR) & 0x0780) | (RDR+LSBONLY),
+		      info->io_base + CCAR );
+		DataByte = inb( info->io_base + CCAR );
+
+		/* get the status of the received byte */
+		status = usc_InReg(info, RCSR);
+		if ( status & (RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR +
+				RXSTATUS_OVERRUN + RXSTATUS_BREAK_RECEIVED) )
+			usc_UnlatchRxstatusBits(info,RXSTATUS_ALL);
+		
+		if (tty->flip.count >= TTY_FLIPBUF_SIZE)
+			continue;
+			
+		*tty->flip.char_buf_ptr = DataByte;
+		icount->rx++;
+		
+		*tty->flip.flag_buf_ptr = 0;
+		if ( status & (RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR +
+				RXSTATUS_OVERRUN + RXSTATUS_BREAK_RECEIVED) ) {
+			printk("rxerr=%04X\n",status);					
+			/* update error statistics */
+			if ( status & RXSTATUS_BREAK_RECEIVED ) {
+				status &= ~(RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR);
+				icount->brk++;
+			} else if (status & RXSTATUS_PARITY_ERROR) 
+				icount->parity++;
+			else if (status & RXSTATUS_FRAMING_ERROR)
+				icount->frame++;
+			else if (status & RXSTATUS_OVERRUN) {
+				/* must issue purge fifo cmd before */
+				/* 16C32 accepts more receive chars */
+				usc_RTCmd(info,RTCmd_PurgeRxFifo);
+				icount->overrun++;
+			}
+
+			/* discard char if tty control flags say so */					
+			if (status & info->ignore_status_mask)
+				continue;
+				
+			status &= info->read_status_mask;
+		
+			if (status & RXSTATUS_BREAK_RECEIVED) {
+				*tty->flip.flag_buf_ptr = TTY_BREAK;
+				if (info->flags & ASYNC_SAK)
+					do_SAK(tty);
+			} else if (status & RXSTATUS_PARITY_ERROR)
+				*tty->flip.flag_buf_ptr = TTY_PARITY;
+			else if (status & RXSTATUS_FRAMING_ERROR)
+				*tty->flip.flag_buf_ptr = TTY_FRAME;
+			if (status & RXSTATUS_OVERRUN) {
+				/* Overrun is special, since it's
+				 * reported immediately, and doesn't
+				 * affect the current character
+				 */
+				if (tty->flip.count < TTY_FLIPBUF_SIZE) {
+					tty->flip.count++;
+					tty->flip.flag_buf_ptr++;
+					tty->flip.char_buf_ptr++;
+					*tty->flip.flag_buf_ptr = TTY_OVERRUN;
+				}
+			}
+		}	/* end of if (error) */
+		
+		tty->flip.flag_buf_ptr++;
+		tty->flip.char_buf_ptr++;
+		tty->flip.count++;
+	}
+
+	if ( debug_level >= DEBUG_LEVEL_ISR ) {
+		printk("%s(%d):mgsl_isr_receive_data flip count=%d\n",
+			__FILE__,__LINE__,tty->flip.count);
+		printk("%s(%d):rx=%d brk=%d parity=%d frame=%d overrun=%d\n",
+			__FILE__,__LINE__,icount->rx,icount->brk,
+			icount->parity,icount->frame,icount->overrun);
+	}
+			
+	if ( tty->flip.count )
+		tty_flip_buffer_push(tty);
+}
+
+/* mgsl_isr_misc()
+ * 
+ * 	Service a miscellaneos interrupt source.
+ * 	
+ * Arguments:		info		pointer to device extension (instance data)
+ * Return Value:	None
+ */
+static void mgsl_isr_misc( struct mgsl_struct *info )
+{
+	u16 status = usc_InReg( info, MISR );
+
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_isr_misc status=%04X\n",
+			__FILE__,__LINE__,status);
+			
+	if ((status & MISCSTATUS_RCC_UNDERRUN) &&
+	    (info->params.mode == MGSL_MODE_HDLC)) {
+
+		/* turn off receiver and rx DMA */
+		usc_EnableReceiver(info,DISABLE_UNCONDITIONAL);
+		usc_DmaCmd(info, DmaCmd_ResetRxChannel);
+		usc_UnlatchRxstatusBits(info, RXSTATUS_ALL);
+		usc_ClearIrqPendingBits(info, RECEIVE_DATA + RECEIVE_STATUS);
+		usc_DisableInterrupts(info, RECEIVE_DATA + RECEIVE_STATUS);
+
+		/* schedule BH handler to restart receiver */
+		info->pending_bh |= BH_RECEIVE;
+		info->rx_rcc_underrun = 1;
+	}
+
+	usc_ClearIrqPendingBits( info, MISC );
+	usc_UnlatchMiscstatusBits( info, status );
+
+}	/* end of mgsl_isr_misc() */
+
+/* mgsl_isr_null()
+ *
+ * 	Services undefined interrupt vectors from the
+ * 	USC. (hence this function SHOULD never be called)
+ * 
+ * Arguments:		info		pointer to device extension (instance data)
+ * Return Value:	None
+ */
+static void mgsl_isr_null( struct mgsl_struct *info )
+{
+
+}	/* end of mgsl_isr_null() */
+
+/* mgsl_isr_receive_dma()
+ * 
+ * 	Service a receive DMA channel interrupt.
+ * 	For this driver there are two sources of receive DMA interrupts
+ * 	as identified in the Receive DMA mode Register (RDMR):
+ * 
+ * 	BIT3	EOA/EOL		End of List, all receive buffers in receive
+ * 				buffer list have been filled (no more free buffers
+ * 				available). The DMA controller has shut down.
+ * 
+ * 	BIT2	EOB		End of Buffer. This interrupt occurs when a receive
+ * 				DMA buffer is terminated in response to completion
+ * 				of a good frame or a frame with errors. The status
+ * 				of the frame is stored in the buffer entry in the
+ * 				list of receive buffer entries.
+ * 
+ * Arguments:		info		pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_isr_receive_dma( struct mgsl_struct *info )
+{
+	u16 status;
+	
+	/* clear interrupt pending and IUS bit for Rx DMA IRQ */
+	usc_OutDmaReg( info, CDIR, BIT9+BIT1 );
+
+	/* Read the receive DMA status to identify interrupt type. */
+	/* This also clears the status bits. */
+	status = usc_InDmaReg( info, RDMR );
+
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_isr_receive_dma(%s) status=%04X\n",
+			__FILE__,__LINE__,info->device_name,status);
+			
+	info->pending_bh |= BH_RECEIVE;
+	
+	if ( status & BIT3 ) {
+		info->rx_overflow = 1;
+		info->icount.buf_overrun++;
+	}
+
+}	/* end of mgsl_isr_receive_dma() */
+
+/* mgsl_isr_transmit_dma()
+ *
+ *	This function services a transmit DMA channel interrupt.
+ *
+ *	For this driver there is one source of transmit DMA interrupts
+ *	as identified in the Transmit DMA Mode Register (TDMR):
+ *
+ *     	BIT2  EOB       End of Buffer. This interrupt occurs when a
+ *     			transmit DMA buffer has been emptied.
+ *
+ *     	The driver maintains enough transmit DMA buffers to hold at least
+ *     	one max frame size transmit frame. When operating in a buffered
+ *     	transmit mode, there may be enough transmit DMA buffers to hold at
+ *     	least two or more max frame size frames. On an EOB condition,
+ *     	determine if there are any queued transmit buffers and copy into
+ *     	transmit DMA buffers if we have room.
+ *
+ * Arguments:		info		pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_isr_transmit_dma( struct mgsl_struct *info )
+{
+	u16 status;
+
+	/* clear interrupt pending and IUS bit for Tx DMA IRQ */
+	usc_OutDmaReg(info, CDIR, BIT8+BIT0 );
+
+	/* Read the transmit DMA status to identify interrupt type. */
+	/* This also clears the status bits. */
+
+	status = usc_InDmaReg( info, TDMR );
+
+	if ( debug_level >= DEBUG_LEVEL_ISR )
+		printk("%s(%d):mgsl_isr_transmit_dma(%s) status=%04X\n",
+			__FILE__,__LINE__,info->device_name,status);
+
+	if ( status & BIT2 ) {
+		--info->tx_dma_buffers_used;
+
+		/* if there are transmit frames queued,
+		 *  try to load the next one
+		 */
+		if ( load_next_tx_holding_buffer(info) ) {
+			/* if call returns non-zero value, we have
+			 * at least one free tx holding buffer
+			 */
+			info->pending_bh |= BH_TRANSMIT;
+		}
+	}
+
+}	/* end of mgsl_isr_transmit_dma() */
+
+/* mgsl_interrupt()
+ * 
+ * 	Interrupt service routine entry point.
+ * 	
+ * Arguments:
+ * 
+ * 	irq		interrupt number that caused interrupt
+ * 	dev_id		device ID supplied during interrupt registration
+ * 	regs		interrupted processor context
+ * 	
+ * Return Value: None
+ */
+static irqreturn_t mgsl_interrupt(int irq, void *dev_id, struct pt_regs * regs)
+{
+	struct mgsl_struct * info;
+	u16 UscVector;
+	u16 DmaVector;
+
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_interrupt(%d)entry.\n",
+			__FILE__,__LINE__,irq);
+
+	info = (struct mgsl_struct *)dev_id;	
+	if (!info)
+		return IRQ_NONE;
+		
+	spin_lock(&info->irq_spinlock);
+
+	for(;;) {
+		/* Read the interrupt vectors from hardware. */
+		UscVector = usc_InReg(info, IVR) >> 9;
+		DmaVector = usc_InDmaReg(info, DIVR);
+		
+		if ( debug_level >= DEBUG_LEVEL_ISR )	
+			printk("%s(%d):%s UscVector=%08X DmaVector=%08X\n",
+				__FILE__,__LINE__,info->device_name,UscVector,DmaVector);
+			
+		if ( !UscVector && !DmaVector )
+			break;
+			
+		/* Dispatch interrupt vector */
+		if ( UscVector )
+			(*UscIsrTable[UscVector])(info);
+		else if ( (DmaVector&(BIT10|BIT9)) == BIT10)
+			mgsl_isr_transmit_dma(info);
+		else
+			mgsl_isr_receive_dma(info);
+
+		if ( info->isr_overflow ) {
+			printk(KERN_ERR"%s(%d):%s isr overflow irq=%d\n",
+				__FILE__,__LINE__,info->device_name, irq);
+			usc_DisableMasterIrqBit(info);
+			usc_DisableDmaInterrupts(info,DICR_MASTER);
+			break;
+		}
+	}
+	
+	/* Request bottom half processing if there's something 
+	 * for it to do and the bh is not already running
+	 */
+
+	if ( info->pending_bh && !info->bh_running && !info->bh_requested ) {
+		if ( debug_level >= DEBUG_LEVEL_ISR )	
+			printk("%s(%d):%s queueing bh task.\n",
+				__FILE__,__LINE__,info->device_name);
+		schedule_work(&info->task);
+		info->bh_requested = 1;
+	}
+
+	spin_unlock(&info->irq_spinlock);
+	
+	if ( debug_level >= DEBUG_LEVEL_ISR )	
+		printk("%s(%d):mgsl_interrupt(%d)exit.\n",
+			__FILE__,__LINE__,irq);
+	return IRQ_HANDLED;
+}	/* end of mgsl_interrupt() */
+
+/* startup()
+ * 
+ * 	Initialize and start device.
+ * 	
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	0 if success, otherwise error code
+ */
+static int startup(struct mgsl_struct * info)
+{
+	int retval = 0;
+	
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk("%s(%d):mgsl_startup(%s)\n",__FILE__,__LINE__,info->device_name);
+		
+	if (info->flags & ASYNC_INITIALIZED)
+		return 0;
+	
+	if (!info->xmit_buf) {
+		/* allocate a page of memory for a transmit buffer */
+		info->xmit_buf = (unsigned char *)get_zeroed_page(GFP_KERNEL);
+		if (!info->xmit_buf) {
+			printk(KERN_ERR"%s(%d):%s can't allocate transmit buffer\n",
+				__FILE__,__LINE__,info->device_name);
+			return -ENOMEM;
+		}
+	}
+
+	info->pending_bh = 0;
+	
+	init_timer(&info->tx_timer);
+	info->tx_timer.data = (unsigned long)info;
+	info->tx_timer.function = mgsl_tx_timeout;
+	
+	/* Allocate and claim adapter resources */
+	retval = mgsl_claim_resources(info);
+	
+	/* perform existence check and diagnostics */
+	if ( !retval )
+		retval = mgsl_adapter_test(info);
+		
+	if ( retval ) {
+  		if (capable(CAP_SYS_ADMIN) && info->tty)
+			set_bit(TTY_IO_ERROR, &info->tty->flags);
+		mgsl_release_resources(info);
+  		return retval;
+  	}
+
+	/* program hardware for current parameters */
+	mgsl_change_params(info);
+	
+	if (info->tty)
+		clear_bit(TTY_IO_ERROR, &info->tty->flags);
+
+	info->flags |= ASYNC_INITIALIZED;
+	
+	return 0;
+	
+}	/* end of startup() */
+
+/* shutdown()
+ *
+ * Called by mgsl_close() and mgsl_hangup() to shutdown hardware
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void shutdown(struct mgsl_struct * info)
+{
+	unsigned long flags;
+	
+	if (!(info->flags & ASYNC_INITIALIZED))
+		return;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_shutdown(%s)\n",
+			 __FILE__,__LINE__, info->device_name );
+
+	/* clear status wait queue because status changes */
+	/* can't happen after shutting down the hardware */
+	wake_up_interruptible(&info->status_event_wait_q);
+	wake_up_interruptible(&info->event_wait_q);
+
+	del_timer(&info->tx_timer);	
+
+	if (info->xmit_buf) {
+		free_page((unsigned long) info->xmit_buf);
+		info->xmit_buf = NULL;
+	}
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	usc_DisableMasterIrqBit(info);
+	usc_stop_receiver(info);
+	usc_stop_transmitter(info);
+	usc_DisableInterrupts(info,RECEIVE_DATA + RECEIVE_STATUS +
+		TRANSMIT_DATA + TRANSMIT_STATUS + IO_PIN + MISC );
+	usc_DisableDmaInterrupts(info,DICR_MASTER + DICR_TRANSMIT + DICR_RECEIVE);
+	
+	/* Disable DMAEN (Port 7, Bit 14) */
+	/* This disconnects the DMA request signal from the ISA bus */
+	/* on the ISA adapter. This has no effect for the PCI adapter */
+	usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT15) | BIT14));
+	
+	/* Disable INTEN (Port 6, Bit12) */
+	/* This disconnects the IRQ request signal to the ISA bus */
+	/* on the ISA adapter. This has no effect for the PCI adapter */
+	usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT13) | BIT12));
+	
+ 	if (!info->tty || info->tty->termios->c_cflag & HUPCL) {
+ 		info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+		usc_set_serial_signals(info);
+	}
+	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	mgsl_release_resources(info);	
+	
+	if (info->tty)
+		set_bit(TTY_IO_ERROR, &info->tty->flags);
+
+	info->flags &= ~ASYNC_INITIALIZED;
+	
+}	/* end of shutdown() */
+
+static void mgsl_program_hw(struct mgsl_struct *info)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	
+	usc_stop_receiver(info);
+	usc_stop_transmitter(info);
+	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+	
+	if (info->params.mode == MGSL_MODE_HDLC ||
+	    info->params.mode == MGSL_MODE_RAW ||
+	    info->netcount)
+		usc_set_sync_mode(info);
+	else
+		usc_set_async_mode(info);
+		
+	usc_set_serial_signals(info);
+	
+	info->dcd_chkcount = 0;
+	info->cts_chkcount = 0;
+	info->ri_chkcount = 0;
+	info->dsr_chkcount = 0;
+
+	usc_EnableStatusIrqs(info,SICR_CTS+SICR_DSR+SICR_DCD+SICR_RI);		
+	usc_EnableInterrupts(info, IO_PIN);
+	usc_get_serial_signals(info);
+		
+	if (info->netcount || info->tty->termios->c_cflag & CREAD)
+		usc_start_receiver(info);
+		
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+}
+
+/* Reconfigure adapter based on new parameters
+ */
+static void mgsl_change_params(struct mgsl_struct *info)
+{
+	unsigned cflag;
+	int bits_per_char;
+
+	if (!info->tty || !info->tty->termios)
+		return;
+		
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_change_params(%s)\n",
+			 __FILE__,__LINE__, info->device_name );
+			 
+	cflag = info->tty->termios->c_cflag;
+
+	/* if B0 rate (hangup) specified then negate DTR and RTS */
+	/* otherwise assert DTR and RTS */
+ 	if (cflag & CBAUD)
+		info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+	else
+		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+	
+	/* byte size and parity */
+	
+	switch (cflag & CSIZE) {
+	      case CS5: info->params.data_bits = 5; break;
+	      case CS6: info->params.data_bits = 6; break;
+	      case CS7: info->params.data_bits = 7; break;
+	      case CS8: info->params.data_bits = 8; break;
+	      /* Never happens, but GCC is too dumb to figure it out */
+	      default:  info->params.data_bits = 7; break;
+	      }
+	      
+	if (cflag & CSTOPB)
+		info->params.stop_bits = 2;
+	else
+		info->params.stop_bits = 1;
+
+	info->params.parity = ASYNC_PARITY_NONE;
+	if (cflag & PARENB) {
+		if (cflag & PARODD)
+			info->params.parity = ASYNC_PARITY_ODD;
+		else
+			info->params.parity = ASYNC_PARITY_EVEN;
+#ifdef CMSPAR
+		if (cflag & CMSPAR)
+			info->params.parity = ASYNC_PARITY_SPACE;
+#endif
+	}
+
+	/* calculate number of jiffies to transmit a full
+	 * FIFO (32 bytes) at specified data rate
+	 */
+	bits_per_char = info->params.data_bits + 
+			info->params.stop_bits + 1;
+
+	/* if port data rate is set to 460800 or less then
+	 * allow tty settings to override, otherwise keep the
+	 * current data rate.
+	 */
+	if (info->params.data_rate <= 460800)
+		info->params.data_rate = tty_get_baud_rate(info->tty);
+	
+	if ( info->params.data_rate ) {
+		info->timeout = (32*HZ*bits_per_char) / 
+				info->params.data_rate;
+	}
+	info->timeout += HZ/50;		/* Add .02 seconds of slop */
+
+	if (cflag & CRTSCTS)
+		info->flags |= ASYNC_CTS_FLOW;
+	else
+		info->flags &= ~ASYNC_CTS_FLOW;
+		
+	if (cflag & CLOCAL)
+		info->flags &= ~ASYNC_CHECK_CD;
+	else
+		info->flags |= ASYNC_CHECK_CD;
+
+	/* process tty input control flags */
+	
+	info->read_status_mask = RXSTATUS_OVERRUN;
+	if (I_INPCK(info->tty))
+		info->read_status_mask |= RXSTATUS_PARITY_ERROR | RXSTATUS_FRAMING_ERROR;
+ 	if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
+ 		info->read_status_mask |= RXSTATUS_BREAK_RECEIVED;
+	
+	if (I_IGNPAR(info->tty))
+		info->ignore_status_mask |= RXSTATUS_PARITY_ERROR | RXSTATUS_FRAMING_ERROR;
+	if (I_IGNBRK(info->tty)) {
+		info->ignore_status_mask |= RXSTATUS_BREAK_RECEIVED;
+		/* If ignoring parity and break indicators, ignore 
+		 * overruns too.  (For real raw support).
+		 */
+		if (I_IGNPAR(info->tty))
+			info->ignore_status_mask |= RXSTATUS_OVERRUN;
+	}
+
+	mgsl_program_hw(info);
+
+}	/* end of mgsl_change_params() */
+
+/* mgsl_put_char()
+ * 
+ * 	Add a character to the transmit buffer.
+ * 	
+ * Arguments:		tty	pointer to tty information structure
+ * 			ch	character to add to transmit buffer
+ * 		
+ * Return Value:	None
+ */
+static void mgsl_put_char(struct tty_struct *tty, unsigned char ch)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+
+	if ( debug_level >= DEBUG_LEVEL_INFO ) {
+		printk( "%s(%d):mgsl_put_char(%d) on %s\n",
+			__FILE__,__LINE__,ch,info->device_name);
+	}		
+	
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_put_char"))
+		return;
+
+	if (!tty || !info->xmit_buf)
+		return;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	
+	if ( (info->params.mode == MGSL_MODE_ASYNC ) || !info->tx_active ) {
+	
+		if (info->xmit_cnt < SERIAL_XMIT_SIZE - 1) {
+			info->xmit_buf[info->xmit_head++] = ch;
+			info->xmit_head &= SERIAL_XMIT_SIZE-1;
+			info->xmit_cnt++;
+		}
+	}
+	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+}	/* end of mgsl_put_char() */
+
+/* mgsl_flush_chars()
+ * 
+ * 	Enable transmitter so remaining characters in the
+ * 	transmit buffer are sent.
+ * 	
+ * Arguments:		tty	pointer to tty information structure
+ * Return Value:	None
+ */
+static void mgsl_flush_chars(struct tty_struct *tty)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+				
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):mgsl_flush_chars() entry on %s xmit_cnt=%d\n",
+			__FILE__,__LINE__,info->device_name,info->xmit_cnt);
+	
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_flush_chars"))
+		return;
+
+	if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
+	    !info->xmit_buf)
+		return;
+
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):mgsl_flush_chars() entry on %s starting transmitter\n",
+			__FILE__,__LINE__,info->device_name );
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	
+	if (!info->tx_active) {
+		if ( (info->params.mode == MGSL_MODE_HDLC ||
+			info->params.mode == MGSL_MODE_RAW) && info->xmit_cnt ) {
+			/* operating in synchronous (frame oriented) mode */
+			/* copy data from circular xmit_buf to */
+			/* transmit DMA buffer. */
+			mgsl_load_tx_dma_buffer(info,
+				 info->xmit_buf,info->xmit_cnt);
+		}
+	 	usc_start_transmitter(info);
+	}
+	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+}	/* end of mgsl_flush_chars() */
+
+/* mgsl_write()
+ * 
+ * 	Send a block of data
+ * 	
+ * Arguments:
+ * 
+ * 	tty		pointer to tty information structure
+ * 	buf		pointer to buffer containing send data
+ * 	count		size of send data in bytes
+ * 	
+ * Return Value:	number of characters written
+ */
+static int mgsl_write(struct tty_struct * tty,
+		    const unsigned char *buf, int count)
+{
+	int	c, ret = 0;
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):mgsl_write(%s) count=%d\n",
+			__FILE__,__LINE__,info->device_name,count);
+	
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_write"))
+		goto cleanup;
+
+	if (!tty || !info->xmit_buf || !tmp_buf)
+		goto cleanup;
+
+	if ( info->params.mode == MGSL_MODE_HDLC ||
+			info->params.mode == MGSL_MODE_RAW ) {
+		/* operating in synchronous (frame oriented) mode */
+		/* operating in synchronous (frame oriented) mode */
+		if (info->tx_active) {
+
+			if ( info->params.mode == MGSL_MODE_HDLC ) {
+				ret = 0;
+				goto cleanup;
+			}
+			/* transmitter is actively sending data -
+			 * if we have multiple transmit dma and
+			 * holding buffers, attempt to queue this
+			 * frame for transmission at a later time.
+			 */
+			if (info->tx_holding_count >= info->num_tx_holding_buffers ) {
+				/* no tx holding buffers available */
+				ret = 0;
+				goto cleanup;
+			}
+
+			/* queue transmit frame request */
+			ret = count;
+			save_tx_buffer_request(info,buf,count);
+
+			/* if we have sufficient tx dma buffers,
+			 * load the next buffered tx request
+			 */
+			spin_lock_irqsave(&info->irq_spinlock,flags);
+			load_next_tx_holding_buffer(info);
+			spin_unlock_irqrestore(&info->irq_spinlock,flags);
+			goto cleanup;
+		}
+	
+		/* if operating in HDLC LoopMode and the adapter  */
+		/* has yet to be inserted into the loop, we can't */
+		/* transmit					  */
+
+		if ( (info->params.flags & HDLC_FLAG_HDLC_LOOPMODE) &&
+			!usc_loopmode_active(info) )
+		{
+			ret = 0;
+			goto cleanup;
+		}
+
+		if ( info->xmit_cnt ) {
+			/* Send accumulated from send_char() calls */
+			/* as frame and wait before accepting more data. */
+			ret = 0;
+			
+			/* copy data from circular xmit_buf to */
+			/* transmit DMA buffer. */
+			mgsl_load_tx_dma_buffer(info,
+				info->xmit_buf,info->xmit_cnt);
+			if ( debug_level >= DEBUG_LEVEL_INFO )
+				printk( "%s(%d):mgsl_write(%s) sync xmit_cnt flushing\n",
+					__FILE__,__LINE__,info->device_name);
+		} else {
+			if ( debug_level >= DEBUG_LEVEL_INFO )
+				printk( "%s(%d):mgsl_write(%s) sync transmit accepted\n",
+					__FILE__,__LINE__,info->device_name);
+			ret = count;
+			info->xmit_cnt = count;
+			mgsl_load_tx_dma_buffer(info,buf,count);
+		}
+	} else {
+		while (1) {
+			spin_lock_irqsave(&info->irq_spinlock,flags);
+			c = min_t(int, count,
+				min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
+				    SERIAL_XMIT_SIZE - info->xmit_head));
+			if (c <= 0) {
+				spin_unlock_irqrestore(&info->irq_spinlock,flags);
+				break;
+			}
+			memcpy(info->xmit_buf + info->xmit_head, buf, c);
+			info->xmit_head = ((info->xmit_head + c) &
+					   (SERIAL_XMIT_SIZE-1));
+			info->xmit_cnt += c;
+			spin_unlock_irqrestore(&info->irq_spinlock,flags);
+			buf += c;
+			count -= c;
+			ret += c;
+		}
+	}	
+	
+ 	if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) {
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		if (!info->tx_active)
+		 	usc_start_transmitter(info);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+ 	}
+cleanup:	
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):mgsl_write(%s) returning=%d\n",
+			__FILE__,__LINE__,info->device_name,ret);
+			
+	return ret;
+	
+}	/* end of mgsl_write() */
+
+/* mgsl_write_room()
+ *
+ *	Return the count of free bytes in transmit buffer
+ * 	
+ * Arguments:		tty	pointer to tty info structure
+ * Return Value:	None
+ */
+static int mgsl_write_room(struct tty_struct *tty)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	int	ret;
+				
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_write_room"))
+		return 0;
+	ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
+	if (ret < 0)
+		ret = 0;
+		
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_write_room(%s)=%d\n",
+			 __FILE__,__LINE__, info->device_name,ret );
+			 
+	if ( info->params.mode == MGSL_MODE_HDLC ||
+		info->params.mode == MGSL_MODE_RAW ) {
+		/* operating in synchronous (frame oriented) mode */
+		if ( info->tx_active )
+			return 0;
+		else
+			return HDLC_MAX_FRAME_SIZE;
+	}
+	
+	return ret;
+	
+}	/* end of mgsl_write_room() */
+
+/* mgsl_chars_in_buffer()
+ *
+ *	Return the count of bytes in transmit buffer
+ * 	
+ * Arguments:		tty	pointer to tty info structure
+ * Return Value:	None
+ */
+static int mgsl_chars_in_buffer(struct tty_struct *tty)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+			 
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_chars_in_buffer(%s)\n",
+			 __FILE__,__LINE__, info->device_name );
+			 
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_chars_in_buffer"))
+		return 0;
+		
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_chars_in_buffer(%s)=%d\n",
+			 __FILE__,__LINE__, info->device_name,info->xmit_cnt );
+			 
+	if ( info->params.mode == MGSL_MODE_HDLC ||
+		info->params.mode == MGSL_MODE_RAW ) {
+		/* operating in synchronous (frame oriented) mode */
+		if ( info->tx_active )
+			return info->max_frame_size;
+		else
+			return 0;
+	}
+			 
+	return info->xmit_cnt;
+}	/* end of mgsl_chars_in_buffer() */
+
+/* mgsl_flush_buffer()
+ *
+ *	Discard all data in the send buffer
+ * 	
+ * Arguments:		tty	pointer to tty info structure
+ * Return Value:	None
+ */
+static void mgsl_flush_buffer(struct tty_struct *tty)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_flush_buffer(%s) entry\n",
+			 __FILE__,__LINE__, info->device_name );
+	
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_flush_buffer"))
+		return;
+		
+	spin_lock_irqsave(&info->irq_spinlock,flags); 
+	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+	del_timer(&info->tx_timer);	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+	wake_up_interruptible(&tty->write_wait);
+	tty_wakeup(tty);
+}
+
+/* mgsl_send_xchar()
+ *
+ *	Send a high-priority XON/XOFF character
+ * 	
+ * Arguments:		tty	pointer to tty info structure
+ *			ch	character to send
+ * Return Value:	None
+ */
+static void mgsl_send_xchar(struct tty_struct *tty, char ch)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_send_xchar(%s,%d)\n",
+			 __FILE__,__LINE__, info->device_name, ch );
+			 
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_send_xchar"))
+		return;
+
+	info->x_char = ch;
+	if (ch) {
+		/* Make sure transmit interrupts are on */
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		if (!info->tx_enabled)
+		 	usc_start_transmitter(info);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	}
+}	/* end of mgsl_send_xchar() */
+
+/* mgsl_throttle()
+ * 
+ * 	Signal remote device to throttle send data (our receive data)
+ * 	
+ * Arguments:		tty	pointer to tty info structure
+ * Return Value:	None
+ */
+static void mgsl_throttle(struct tty_struct * tty)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_throttle(%s) entry\n",
+			 __FILE__,__LINE__, info->device_name );
+
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_throttle"))
+		return;
+	
+	if (I_IXOFF(tty))
+		mgsl_send_xchar(tty, STOP_CHAR(tty));
+ 
+ 	if (tty->termios->c_cflag & CRTSCTS) {
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		info->serial_signals &= ~SerialSignal_RTS;
+	 	usc_set_serial_signals(info);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	}
+}	/* end of mgsl_throttle() */
+
+/* mgsl_unthrottle()
+ * 
+ * 	Signal remote device to stop throttling send data (our receive data)
+ * 	
+ * Arguments:		tty	pointer to tty info structure
+ * Return Value:	None
+ */
+static void mgsl_unthrottle(struct tty_struct * tty)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_unthrottle(%s) entry\n",
+			 __FILE__,__LINE__, info->device_name );
+
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_unthrottle"))
+		return;
+	
+	if (I_IXOFF(tty)) {
+		if (info->x_char)
+			info->x_char = 0;
+		else
+			mgsl_send_xchar(tty, START_CHAR(tty));
+	}
+	
+ 	if (tty->termios->c_cflag & CRTSCTS) {
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		info->serial_signals |= SerialSignal_RTS;
+	 	usc_set_serial_signals(info);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	}
+	
+}	/* end of mgsl_unthrottle() */
+
+/* mgsl_get_stats()
+ * 
+ * 	get the current serial parameters information
+ *
+ * Arguments:	info		pointer to device instance data
+ * 		user_icount	pointer to buffer to hold returned stats
+ * 	
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_get_stats(struct mgsl_struct * info, struct mgsl_icount __user *user_icount)
+{
+	int err;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_get_params(%s)\n",
+			 __FILE__,__LINE__, info->device_name);
+			
+	COPY_TO_USER(err,user_icount, &info->icount, sizeof(struct mgsl_icount));
+	if (err) {
+		if ( debug_level >= DEBUG_LEVEL_INFO )
+			printk( "%s(%d):mgsl_get_stats(%s) user buffer copy failed\n",
+				__FILE__,__LINE__,info->device_name);
+		return -EFAULT;
+	}
+	
+	return 0;
+	
+}	/* end of mgsl_get_stats() */
+
+/* mgsl_get_params()
+ * 
+ * 	get the current serial parameters information
+ *
+ * Arguments:	info		pointer to device instance data
+ * 		user_params	pointer to buffer to hold returned params
+ * 	
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_get_params(struct mgsl_struct * info, MGSL_PARAMS __user *user_params)
+{
+	int err;
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_get_params(%s)\n",
+			 __FILE__,__LINE__, info->device_name);
+			
+	COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
+	if (err) {
+		if ( debug_level >= DEBUG_LEVEL_INFO )
+			printk( "%s(%d):mgsl_get_params(%s) user buffer copy failed\n",
+				__FILE__,__LINE__,info->device_name);
+		return -EFAULT;
+	}
+	
+	return 0;
+	
+}	/* end of mgsl_get_params() */
+
+/* mgsl_set_params()
+ * 
+ * 	set the serial parameters
+ * 	
+ * Arguments:
+ * 
+ * 	info		pointer to device instance data
+ * 	new_params	user buffer containing new serial params
+ *
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_set_params(struct mgsl_struct * info, MGSL_PARAMS __user *new_params)
+{
+ 	unsigned long flags;
+	MGSL_PARAMS tmp_params;
+	int err;
+ 
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_set_params %s\n", __FILE__,__LINE__,
+			info->device_name );
+	COPY_FROM_USER(err,&tmp_params, new_params, sizeof(MGSL_PARAMS));
+	if (err) {
+		if ( debug_level >= DEBUG_LEVEL_INFO )
+			printk( "%s(%d):mgsl_set_params(%s) user buffer copy failed\n",
+				__FILE__,__LINE__,info->device_name);
+		return -EFAULT;
+	}
+	
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+ 	mgsl_change_params(info);
+	
+	return 0;
+	
+}	/* end of mgsl_set_params() */
+
+/* mgsl_get_txidle()
+ * 
+ * 	get the current transmit idle mode
+ *
+ * Arguments:	info		pointer to device instance data
+ * 		idle_mode	pointer to buffer to hold returned idle mode
+ * 	
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_get_txidle(struct mgsl_struct * info, int __user *idle_mode)
+{
+	int err;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_get_txidle(%s)=%d\n",
+			 __FILE__,__LINE__, info->device_name, info->idle_mode);
+			
+	COPY_TO_USER(err,idle_mode, &info->idle_mode, sizeof(int));
+	if (err) {
+		if ( debug_level >= DEBUG_LEVEL_INFO )
+			printk( "%s(%d):mgsl_get_txidle(%s) user buffer copy failed\n",
+				__FILE__,__LINE__,info->device_name);
+		return -EFAULT;
+	}
+	
+	return 0;
+	
+}	/* end of mgsl_get_txidle() */
+
+/* mgsl_set_txidle()	service ioctl to set transmit idle mode
+ * 	
+ * Arguments:	 	info		pointer to device instance data
+ * 			idle_mode	new idle mode
+ *
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_set_txidle(struct mgsl_struct * info, int idle_mode)
+{
+ 	unsigned long flags;
+ 
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_set_txidle(%s,%d)\n", __FILE__,__LINE__,
+			info->device_name, idle_mode );
+			
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	info->idle_mode = idle_mode;
+	usc_set_txidle( info );
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	return 0;
+	
+}	/* end of mgsl_set_txidle() */
+
+/* mgsl_txenable()
+ * 
+ * 	enable or disable the transmitter
+ * 	
+ * Arguments:
+ * 
+ * 	info		pointer to device instance data
+ * 	enable		1 = enable, 0 = disable
+ *
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_txenable(struct mgsl_struct * info, int enable)
+{
+ 	unsigned long flags;
+ 
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_txenable(%s,%d)\n", __FILE__,__LINE__,
+			info->device_name, enable);
+			
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	if ( enable ) {
+		if ( !info->tx_enabled ) {
+
+			usc_start_transmitter(info);
+			/*--------------------------------------------------
+			 * if HDLC/SDLC Loop mode, attempt to insert the
+			 * station in the 'loop' by setting CMR:13. Upon
+			 * receipt of the next GoAhead (RxAbort) sequence,
+			 * the OnLoop indicator (CCSR:7) should go active
+			 * to indicate that we are on the loop
+			 *--------------------------------------------------*/
+			if ( info->params.flags & HDLC_FLAG_HDLC_LOOPMODE )
+				usc_loopmode_insert_request( info );
+		}
+	} else {
+		if ( info->tx_enabled )
+			usc_stop_transmitter(info);
+	}
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	return 0;
+	
+}	/* end of mgsl_txenable() */
+
+/* mgsl_txabort()	abort send HDLC frame
+ * 	
+ * Arguments:	 	info		pointer to device instance data
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_txabort(struct mgsl_struct * info)
+{
+ 	unsigned long flags;
+ 
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_txabort(%s)\n", __FILE__,__LINE__,
+			info->device_name);
+			
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	if ( info->tx_active && info->params.mode == MGSL_MODE_HDLC )
+	{
+		if ( info->params.flags & HDLC_FLAG_HDLC_LOOPMODE )
+			usc_loopmode_cancel_transmit( info );
+		else
+			usc_TCmd(info,TCmd_SendAbort);
+	}
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	return 0;
+	
+}	/* end of mgsl_txabort() */
+
+/* mgsl_rxenable() 	enable or disable the receiver
+ * 	
+ * Arguments:	 	info		pointer to device instance data
+ * 			enable		1 = enable, 0 = disable
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_rxenable(struct mgsl_struct * info, int enable)
+{
+ 	unsigned long flags;
+ 
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_rxenable(%s,%d)\n", __FILE__,__LINE__,
+			info->device_name, enable);
+			
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	if ( enable ) {
+		if ( !info->rx_enabled )
+			usc_start_receiver(info);
+	} else {
+		if ( info->rx_enabled )
+			usc_stop_receiver(info);
+	}
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	return 0;
+	
+}	/* end of mgsl_rxenable() */
+
+/* mgsl_wait_event() 	wait for specified event to occur
+ * 	
+ * Arguments:	 	info	pointer to device instance data
+ * 			mask	pointer to bitmask of events to wait for
+ * Return Value:	0 	if successful and bit mask updated with
+ *				of events triggerred,
+ * 			otherwise error code
+ */
+static int mgsl_wait_event(struct mgsl_struct * info, int __user * mask_ptr)
+{
+ 	unsigned long flags;
+	int s;
+	int rc=0;
+	struct mgsl_icount cprev, cnow;
+	int events;
+	int mask;
+	struct	_input_signal_events oldsigs, newsigs;
+	DECLARE_WAITQUEUE(wait, current);
+
+	COPY_FROM_USER(rc,&mask, mask_ptr, sizeof(int));
+	if (rc) {
+		return  -EFAULT;
+	}
+		 
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_wait_event(%s,%d)\n", __FILE__,__LINE__,
+			info->device_name, mask);
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+
+	/* return immediately if state matches requested events */
+	usc_get_serial_signals(info);
+	s = info->serial_signals;
+	events = mask &
+		( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
+ 		  ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
+		  ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
+		  ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
+	if (events) {
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+		goto exit;
+	}
+
+	/* save current irq counts */
+	cprev = info->icount;
+	oldsigs = info->input_signal_events;
+	
+	/* enable hunt and idle irqs if needed */
+	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
+		u16 oldreg = usc_InReg(info,RICR);
+		u16 newreg = oldreg +
+			 (mask & MgslEvent_ExitHuntMode ? RXSTATUS_EXITED_HUNT:0) +
+			 (mask & MgslEvent_IdleReceived ? RXSTATUS_IDLE_RECEIVED:0);
+		if (oldreg != newreg)
+			usc_OutReg(info, RICR, newreg);
+	}
+	
+	set_current_state(TASK_INTERRUPTIBLE);
+	add_wait_queue(&info->event_wait_q, &wait);
+	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+
+	for(;;) {
+		schedule();
+		if (signal_pending(current)) {
+			rc = -ERESTARTSYS;
+			break;
+		}
+			
+		/* get current irq counts */
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		cnow = info->icount;
+		newsigs = info->input_signal_events;
+		set_current_state(TASK_INTERRUPTIBLE);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+		/* if no change, wait aborted for some reason */
+		if (newsigs.dsr_up   == oldsigs.dsr_up   &&
+		    newsigs.dsr_down == oldsigs.dsr_down &&
+		    newsigs.dcd_up   == oldsigs.dcd_up   &&
+		    newsigs.dcd_down == oldsigs.dcd_down &&
+		    newsigs.cts_up   == oldsigs.cts_up   &&
+		    newsigs.cts_down == oldsigs.cts_down &&
+		    newsigs.ri_up    == oldsigs.ri_up    &&
+		    newsigs.ri_down  == oldsigs.ri_down  &&
+		    cnow.exithunt    == cprev.exithunt   &&
+		    cnow.rxidle      == cprev.rxidle) {
+			rc = -EIO;
+			break;
+		}
+
+		events = mask &
+			( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
+			(newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
+			(newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
+			(newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
+			(newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
+			(newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
+			(newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
+			(newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
+			(cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
+			  (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
+		if (events)
+			break;
+		
+		cprev = cnow;
+		oldsigs = newsigs;
+	}
+	
+	remove_wait_queue(&info->event_wait_q, &wait);
+	set_current_state(TASK_RUNNING);
+
+	if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		if (!waitqueue_active(&info->event_wait_q)) {
+			/* disable enable exit hunt mode/idle rcvd IRQs */
+			usc_OutReg(info, RICR, usc_InReg(info,RICR) &
+				~(RXSTATUS_EXITED_HUNT + RXSTATUS_IDLE_RECEIVED));
+		}
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	}
+exit:
+	if ( rc == 0 )
+		PUT_USER(rc, events, mask_ptr);
+		
+	return rc;
+	
+}	/* end of mgsl_wait_event() */
+
+static int modem_input_wait(struct mgsl_struct *info,int arg)
+{
+ 	unsigned long flags;
+	int rc;
+	struct mgsl_icount cprev, cnow;
+	DECLARE_WAITQUEUE(wait, current);
+
+	/* save current irq counts */
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	cprev = info->icount;
+	add_wait_queue(&info->status_event_wait_q, &wait);
+	set_current_state(TASK_INTERRUPTIBLE);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	for(;;) {
+		schedule();
+		if (signal_pending(current)) {
+			rc = -ERESTARTSYS;
+			break;
+		}
+
+		/* get new irq counts */
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		cnow = info->icount;
+		set_current_state(TASK_INTERRUPTIBLE);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+		/* if no change, wait aborted for some reason */
+		if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
+		    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
+			rc = -EIO;
+			break;
+		}
+
+		/* check for change in caller specified modem input */
+		if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
+		    (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
+		    (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
+		    (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
+			rc = 0;
+			break;
+		}
+
+		cprev = cnow;
+	}
+	remove_wait_queue(&info->status_event_wait_q, &wait);
+	set_current_state(TASK_RUNNING);
+	return rc;
+}
+
+/* return the state of the serial control and status signals
+ */
+static int tiocmget(struct tty_struct *tty, struct file *file)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned int result;
+ 	unsigned long flags;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+ 	usc_get_serial_signals(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
+		((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
+		((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
+		((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
+		((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
+		((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS:0);
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):%s tiocmget() value=%08X\n",
+			 __FILE__,__LINE__, info->device_name, result );
+	return result;
+}
+
+/* set modem control signals (DTR/RTS)
+ */
+static int tiocmset(struct tty_struct *tty, struct file *file,
+		    unsigned int set, unsigned int clear)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+ 	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):%s tiocmset(%x,%x)\n",
+			__FILE__,__LINE__,info->device_name, set, clear);
+
+	if (set & TIOCM_RTS)
+		info->serial_signals |= SerialSignal_RTS;
+	if (set & TIOCM_DTR)
+		info->serial_signals |= SerialSignal_DTR;
+	if (clear & TIOCM_RTS)
+		info->serial_signals &= ~SerialSignal_RTS;
+	if (clear & TIOCM_DTR)
+		info->serial_signals &= ~SerialSignal_DTR;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+ 	usc_set_serial_signals(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	return 0;
+}
+
+/* mgsl_break()		Set or clear transmit break condition
+ *
+ * Arguments:		tty		pointer to tty instance data
+ *			break_state	-1=set break condition, 0=clear
+ * Return Value:	None
+ */
+static void mgsl_break(struct tty_struct *tty, int break_state)
+{
+	struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_break(%s,%d)\n",
+			 __FILE__,__LINE__, info->device_name, break_state);
+			 
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_break"))
+		return;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+ 	if (break_state == -1)
+		usc_OutReg(info,IOCR,(u16)(usc_InReg(info,IOCR) | BIT7));
+	else 
+		usc_OutReg(info,IOCR,(u16)(usc_InReg(info,IOCR) & ~BIT7));
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+}	/* end of mgsl_break() */
+
+/* mgsl_ioctl()	Service an IOCTL request
+ * 	
+ * Arguments:
+ * 
+ * 	tty	pointer to tty instance data
+ * 	file	pointer to associated file object for device
+ * 	cmd	IOCTL command code
+ * 	arg	command argument/context
+ * 	
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_ioctl(struct tty_struct *tty, struct file * file,
+		    unsigned int cmd, unsigned long arg)
+{
+	struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_ioctl %s cmd=%08X\n", __FILE__,__LINE__,
+			info->device_name, cmd );
+	
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_ioctl"))
+		return -ENODEV;
+
+	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
+	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
+		if (tty->flags & (1 << TTY_IO_ERROR))
+		    return -EIO;
+	}
+
+	return mgsl_ioctl_common(info, cmd, arg);
+}
+
+static int mgsl_ioctl_common(struct mgsl_struct *info, unsigned int cmd, unsigned long arg)
+{
+	int error;
+	struct mgsl_icount cnow;	/* kernel counter temps */
+	void __user *argp = (void __user *)arg;
+	struct serial_icounter_struct __user *p_cuser;	/* user space */
+	unsigned long flags;
+	
+	switch (cmd) {
+		case MGSL_IOCGPARAMS:
+			return mgsl_get_params(info, argp);
+		case MGSL_IOCSPARAMS:
+			return mgsl_set_params(info, argp);
+		case MGSL_IOCGTXIDLE:
+			return mgsl_get_txidle(info, argp);
+		case MGSL_IOCSTXIDLE:
+			return mgsl_set_txidle(info,(int)arg);
+		case MGSL_IOCTXENABLE:
+			return mgsl_txenable(info,(int)arg);
+		case MGSL_IOCRXENABLE:
+			return mgsl_rxenable(info,(int)arg);
+		case MGSL_IOCTXABORT:
+			return mgsl_txabort(info);
+		case MGSL_IOCGSTATS:
+			return mgsl_get_stats(info, argp);
+		case MGSL_IOCWAITEVENT:
+			return mgsl_wait_event(info, argp);
+		case MGSL_IOCLOOPTXDONE:
+			return mgsl_loopmode_send_done(info);
+		/* Wait for modem input (DCD,RI,DSR,CTS) change
+		 * as specified by mask in arg (TIOCM_RNG/DSR/CD/CTS)
+		 */
+		case TIOCMIWAIT:
+			return modem_input_wait(info,(int)arg);
+
+		/* 
+		 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
+		 * Return: write counters to the user passed counter struct
+		 * NB: both 1->0 and 0->1 transitions are counted except for
+		 *     RI where only 0->1 is counted.
+		 */
+		case TIOCGICOUNT:
+			spin_lock_irqsave(&info->irq_spinlock,flags);
+			cnow = info->icount;
+			spin_unlock_irqrestore(&info->irq_spinlock,flags);
+			p_cuser = argp;
+			PUT_USER(error,cnow.cts, &p_cuser->cts);
+			if (error) return error;
+			PUT_USER(error,cnow.dsr, &p_cuser->dsr);
+			if (error) return error;
+			PUT_USER(error,cnow.rng, &p_cuser->rng);
+			if (error) return error;
+			PUT_USER(error,cnow.dcd, &p_cuser->dcd);
+			if (error) return error;
+			PUT_USER(error,cnow.rx, &p_cuser->rx);
+			if (error) return error;
+			PUT_USER(error,cnow.tx, &p_cuser->tx);
+			if (error) return error;
+			PUT_USER(error,cnow.frame, &p_cuser->frame);
+			if (error) return error;
+			PUT_USER(error,cnow.overrun, &p_cuser->overrun);
+			if (error) return error;
+			PUT_USER(error,cnow.parity, &p_cuser->parity);
+			if (error) return error;
+			PUT_USER(error,cnow.brk, &p_cuser->brk);
+			if (error) return error;
+			PUT_USER(error,cnow.buf_overrun, &p_cuser->buf_overrun);
+			if (error) return error;
+			return 0;
+		default:
+			return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+/* mgsl_set_termios()
+ * 
+ * 	Set new termios settings
+ * 	
+ * Arguments:
+ * 
+ * 	tty		pointer to tty structure
+ * 	termios		pointer to buffer to hold returned old termios
+ * 	
+ * Return Value:		None
+ */
+static void mgsl_set_termios(struct tty_struct *tty, struct termios *old_termios)
+{
+	struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long flags;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_set_termios %s\n", __FILE__,__LINE__,
+			tty->driver->name );
+	
+	/* just return if nothing has changed */
+	if ((tty->termios->c_cflag == old_termios->c_cflag)
+	    && (RELEVANT_IFLAG(tty->termios->c_iflag) 
+		== RELEVANT_IFLAG(old_termios->c_iflag)))
+	  return;
+
+	mgsl_change_params(info);
+
+	/* Handle transition to B0 status */
+	if (old_termios->c_cflag & CBAUD &&
+	    !(tty->termios->c_cflag & CBAUD)) {
+		info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+	 	usc_set_serial_signals(info);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	}
+	
+	/* Handle transition away from B0 status */
+	if (!(old_termios->c_cflag & CBAUD) &&
+	    tty->termios->c_cflag & CBAUD) {
+		info->serial_signals |= SerialSignal_DTR;
+ 		if (!(tty->termios->c_cflag & CRTSCTS) || 
+ 		    !test_bit(TTY_THROTTLED, &tty->flags)) {
+			info->serial_signals |= SerialSignal_RTS;
+ 		}
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+	 	usc_set_serial_signals(info);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	}
+	
+	/* Handle turning off CRTSCTS */
+	if (old_termios->c_cflag & CRTSCTS &&
+	    !(tty->termios->c_cflag & CRTSCTS)) {
+		tty->hw_stopped = 0;
+		mgsl_start(tty);
+	}
+
+}	/* end of mgsl_set_termios() */
+
+/* mgsl_close()
+ * 
+ * 	Called when port is closed. Wait for remaining data to be
+ * 	sent. Disable port and free resources.
+ * 	
+ * Arguments:
+ * 
+ * 	tty	pointer to open tty structure
+ * 	filp	pointer to open file object
+ * 	
+ * Return Value:	None
+ */
+static void mgsl_close(struct tty_struct *tty, struct file * filp)
+{
+	struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
+
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_close"))
+		return;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_close(%s) entry, count=%d\n",
+			 __FILE__,__LINE__, info->device_name, info->count);
+			 
+	if (!info->count)
+		return;
+
+	if (tty_hung_up_p(filp))
+		goto cleanup;
+			
+	if ((tty->count == 1) && (info->count != 1)) {
+		/*
+		 * tty->count is 1 and the tty structure will be freed.
+		 * info->count should be one in this case.
+		 * if it's not, correct it so that the port is shutdown.
+		 */
+		printk("mgsl_close: bad refcount; tty->count is 1, "
+		       "info->count is %d\n", info->count);
+		info->count = 1;
+	}
+	
+	info->count--;
+	
+	/* if at least one open remaining, leave hardware active */
+	if (info->count)
+		goto cleanup;
+	
+	info->flags |= ASYNC_CLOSING;
+	
+	/* set tty->closing to notify line discipline to 
+	 * only process XON/XOFF characters. Only the N_TTY
+	 * discipline appears to use this (ppp does not).
+	 */
+	tty->closing = 1;
+	
+	/* wait for transmit data to clear all layers */
+	
+	if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE) {
+		if (debug_level >= DEBUG_LEVEL_INFO)
+			printk("%s(%d):mgsl_close(%s) calling tty_wait_until_sent\n",
+				 __FILE__,__LINE__, info->device_name );
+		tty_wait_until_sent(tty, info->closing_wait);
+	}
+		
+ 	if (info->flags & ASYNC_INITIALIZED)
+ 		mgsl_wait_until_sent(tty, info->timeout);
+
+	if (tty->driver->flush_buffer)
+		tty->driver->flush_buffer(tty);
+
+	tty_ldisc_flush(tty);
+		
+	shutdown(info);
+	
+	tty->closing = 0;
+	info->tty = NULL;
+	
+	if (info->blocked_open) {
+		if (info->close_delay) {
+			msleep_interruptible(jiffies_to_msecs(info->close_delay));
+		}
+		wake_up_interruptible(&info->open_wait);
+	}
+	
+	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
+			 
+	wake_up_interruptible(&info->close_wait);
+	
+cleanup:			
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_close(%s) exit, count=%d\n", __FILE__,__LINE__,
+			tty->driver->name, info->count);
+			
+}	/* end of mgsl_close() */
+
+/* mgsl_wait_until_sent()
+ *
+ *	Wait until the transmitter is empty.
+ *
+ * Arguments:
+ *
+ *	tty		pointer to tty info structure
+ *	timeout		time to wait for send completion
+ *
+ * Return Value:	None
+ */
+static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout)
+{
+	struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
+	unsigned long orig_jiffies, char_time;
+
+	if (!info )
+		return;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_wait_until_sent(%s) entry\n",
+			 __FILE__,__LINE__, info->device_name );
+      
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_wait_until_sent"))
+		return;
+
+	if (!(info->flags & ASYNC_INITIALIZED))
+		goto exit;
+	 
+	orig_jiffies = jiffies;
+      
+	/* Set check interval to 1/5 of estimated time to
+	 * send a character, and make it at least 1. The check
+	 * interval should also be less than the timeout.
+	 * Note: use tight timings here to satisfy the NIST-PCTS.
+	 */ 
+       
+	if ( info->params.data_rate ) {
+	       	char_time = info->timeout/(32 * 5);
+		if (!char_time)
+			char_time++;
+	} else
+		char_time = 1;
+		
+	if (timeout)
+		char_time = min_t(unsigned long, char_time, timeout);
+		
+	if ( info->params.mode == MGSL_MODE_HDLC ||
+		info->params.mode == MGSL_MODE_RAW ) {
+		while (info->tx_active) {
+			msleep_interruptible(jiffies_to_msecs(char_time));
+			if (signal_pending(current))
+				break;
+			if (timeout && time_after(jiffies, orig_jiffies + timeout))
+				break;
+		}
+	} else {
+		while (!(usc_InReg(info,TCSR) & TXSTATUS_ALL_SENT) &&
+			info->tx_enabled) {
+			msleep_interruptible(jiffies_to_msecs(char_time));
+			if (signal_pending(current))
+				break;
+			if (timeout && time_after(jiffies, orig_jiffies + timeout))
+				break;
+		}
+	}
+      
+exit:
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_wait_until_sent(%s) exit\n",
+			 __FILE__,__LINE__, info->device_name );
+			 
+}	/* end of mgsl_wait_until_sent() */
+
+/* mgsl_hangup()
+ *
+ *	Called by tty_hangup() when a hangup is signaled.
+ *	This is the same as to closing all open files for the port.
+ *
+ * Arguments:		tty	pointer to associated tty object
+ * Return Value:	None
+ */
+static void mgsl_hangup(struct tty_struct *tty)
+{
+	struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_hangup(%s)\n",
+			 __FILE__,__LINE__, info->device_name );
+			 
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_hangup"))
+		return;
+
+	mgsl_flush_buffer(tty);
+	shutdown(info);
+	
+	info->count = 0;	
+	info->flags &= ~ASYNC_NORMAL_ACTIVE;
+	info->tty = NULL;
+
+	wake_up_interruptible(&info->open_wait);
+	
+}	/* end of mgsl_hangup() */
+
+/* block_til_ready()
+ * 
+ * 	Block the current process until the specified port
+ * 	is ready to be opened.
+ * 	
+ * Arguments:
+ * 
+ * 	tty		pointer to tty info structure
+ * 	filp		pointer to open file object
+ * 	info		pointer to device instance data
+ * 	
+ * Return Value:	0 if success, otherwise error code
+ */
+static int block_til_ready(struct tty_struct *tty, struct file * filp,
+			   struct mgsl_struct *info)
+{
+	DECLARE_WAITQUEUE(wait, current);
+	int		retval;
+	int		do_clocal = 0, extra_count = 0;
+	unsigned long	flags;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):block_til_ready on %s\n",
+			 __FILE__,__LINE__, tty->driver->name );
+
+	if (filp->f_flags & O_NONBLOCK || tty->flags & (1 << TTY_IO_ERROR)){
+		/* nonblock mode is set or port is not enabled */
+		info->flags |= ASYNC_NORMAL_ACTIVE;
+		return 0;
+	}
+
+	if (tty->termios->c_cflag & CLOCAL)
+		do_clocal = 1;
+
+	/* Wait for carrier detect and the line to become
+	 * free (i.e., not in use by the callout).  While we are in
+	 * this loop, info->count is dropped by one, so that
+	 * mgsl_close() knows when to free things.  We restore it upon
+	 * exit, either normal or abnormal.
+	 */
+	 
+	retval = 0;
+	add_wait_queue(&info->open_wait, &wait);
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):block_til_ready before block on %s count=%d\n",
+			 __FILE__,__LINE__, tty->driver->name, info->count );
+
+	spin_lock_irqsave(&info->irq_spinlock, flags);
+	if (!tty_hung_up_p(filp)) {
+		extra_count = 1;
+		info->count--;
+	}
+	spin_unlock_irqrestore(&info->irq_spinlock, flags);
+	info->blocked_open++;
+	
+	while (1) {
+		if (tty->termios->c_cflag & CBAUD) {
+			spin_lock_irqsave(&info->irq_spinlock,flags);
+			info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+		 	usc_set_serial_signals(info);
+			spin_unlock_irqrestore(&info->irq_spinlock,flags);
+		}
+		
+		set_current_state(TASK_INTERRUPTIBLE);
+		
+		if (tty_hung_up_p(filp) || !(info->flags & ASYNC_INITIALIZED)){
+			retval = (info->flags & ASYNC_HUP_NOTIFY) ?
+					-EAGAIN : -ERESTARTSYS;
+			break;
+		}
+		
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+	 	usc_get_serial_signals(info);
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+		
+ 		if (!(info->flags & ASYNC_CLOSING) &&
+ 		    (do_clocal || (info->serial_signals & SerialSignal_DCD)) ) {
+ 			break;
+		}
+			
+		if (signal_pending(current)) {
+			retval = -ERESTARTSYS;
+			break;
+		}
+		
+		if (debug_level >= DEBUG_LEVEL_INFO)
+			printk("%s(%d):block_til_ready blocking on %s count=%d\n",
+				 __FILE__,__LINE__, tty->driver->name, info->count );
+				 
+		schedule();
+	}
+	
+	set_current_state(TASK_RUNNING);
+	remove_wait_queue(&info->open_wait, &wait);
+	
+	if (extra_count)
+		info->count++;
+	info->blocked_open--;
+	
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):block_til_ready after blocking on %s count=%d\n",
+			 __FILE__,__LINE__, tty->driver->name, info->count );
+			 
+	if (!retval)
+		info->flags |= ASYNC_NORMAL_ACTIVE;
+		
+	return retval;
+	
+}	/* end of block_til_ready() */
+
+/* mgsl_open()
+ *
+ *	Called when a port is opened.  Init and enable port.
+ *	Perform serial-specific initialization for the tty structure.
+ *
+ * Arguments:		tty	pointer to tty info structure
+ *			filp	associated file pointer
+ *
+ * Return Value:	0 if success, otherwise error code
+ */
+static int mgsl_open(struct tty_struct *tty, struct file * filp)
+{
+	struct mgsl_struct	*info;
+	int 			retval, line;
+	unsigned long		page;
+	unsigned long flags;
+
+	/* verify range of specified line number */	
+	line = tty->index;
+	if ((line < 0) || (line >= mgsl_device_count)) {
+		printk("%s(%d):mgsl_open with invalid line #%d.\n",
+			__FILE__,__LINE__,line);
+		return -ENODEV;
+	}
+
+	/* find the info structure for the specified line */
+	info = mgsl_device_list;
+	while(info && info->line != line)
+		info = info->next_device;
+	if (mgsl_paranoia_check(info, tty->name, "mgsl_open"))
+		return -ENODEV;
+	
+	tty->driver_data = info;
+	info->tty = tty;
+		
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_open(%s), old ref count = %d\n",
+			 __FILE__,__LINE__,tty->driver->name, info->count);
+
+	/* If port is closing, signal caller to try again */
+	if (tty_hung_up_p(filp) || info->flags & ASYNC_CLOSING){
+		if (info->flags & ASYNC_CLOSING)
+			interruptible_sleep_on(&info->close_wait);
+		retval = ((info->flags & ASYNC_HUP_NOTIFY) ?
+			-EAGAIN : -ERESTARTSYS);
+		goto cleanup;
+	}
+	
+	if (!tmp_buf) {
+		page = get_zeroed_page(GFP_KERNEL);
+		if (!page) {
+			retval = -ENOMEM;
+			goto cleanup;
+		}
+		if (tmp_buf)
+			free_page(page);
+		else
+			tmp_buf = (unsigned char *) page;
+	}
+	
+	info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
+
+	spin_lock_irqsave(&info->netlock, flags);
+	if (info->netcount) {
+		retval = -EBUSY;
+		spin_unlock_irqrestore(&info->netlock, flags);
+		goto cleanup;
+	}
+	info->count++;
+	spin_unlock_irqrestore(&info->netlock, flags);
+
+	if (info->count == 1) {
+		/* 1st open on this device, init hardware */
+		retval = startup(info);
+		if (retval < 0)
+			goto cleanup;
+	}
+
+	retval = block_til_ready(tty, filp, info);
+	if (retval) {
+		if (debug_level >= DEBUG_LEVEL_INFO)
+			printk("%s(%d):block_til_ready(%s) returned %d\n",
+				 __FILE__,__LINE__, info->device_name, retval);
+		goto cleanup;
+	}
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s(%d):mgsl_open(%s) success\n",
+			 __FILE__,__LINE__, info->device_name);
+	retval = 0;
+	
+cleanup:			
+	if (retval) {
+		if (tty->count == 1)
+			info->tty = NULL; /* tty layer will release tty struct */
+		if(info->count)
+			info->count--;
+	}
+	
+	return retval;
+	
+}	/* end of mgsl_open() */
+
+/*
+ * /proc fs routines....
+ */
+
+static inline int line_info(char *buf, struct mgsl_struct *info)
+{
+	char	stat_buf[30];
+	int	ret;
+	unsigned long flags;
+
+	if (info->bus_type == MGSL_BUS_TYPE_PCI) {
+		ret = sprintf(buf, "%s:PCI io:%04X irq:%d mem:%08X lcr:%08X",
+			info->device_name, info->io_base, info->irq_level,
+			info->phys_memory_base, info->phys_lcr_base);
+	} else {
+		ret = sprintf(buf, "%s:(E)ISA io:%04X irq:%d dma:%d",
+			info->device_name, info->io_base, 
+			info->irq_level, info->dma_level);
+	}
+
+	/* output current serial signal states */
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+ 	usc_get_serial_signals(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+	stat_buf[0] = 0;
+	stat_buf[1] = 0;
+	if (info->serial_signals & SerialSignal_RTS)
+		strcat(stat_buf, "|RTS");
+	if (info->serial_signals & SerialSignal_CTS)
+		strcat(stat_buf, "|CTS");
+	if (info->serial_signals & SerialSignal_DTR)
+		strcat(stat_buf, "|DTR");
+	if (info->serial_signals & SerialSignal_DSR)
+		strcat(stat_buf, "|DSR");
+	if (info->serial_signals & SerialSignal_DCD)
+		strcat(stat_buf, "|CD");
+	if (info->serial_signals & SerialSignal_RI)
+		strcat(stat_buf, "|RI");
+
+	if (info->params.mode == MGSL_MODE_HDLC ||
+	    info->params.mode == MGSL_MODE_RAW ) {
+		ret += sprintf(buf+ret, " HDLC txok:%d rxok:%d",
+			      info->icount.txok, info->icount.rxok);
+		if (info->icount.txunder)
+			ret += sprintf(buf+ret, " txunder:%d", info->icount.txunder);
+		if (info->icount.txabort)
+			ret += sprintf(buf+ret, " txabort:%d", info->icount.txabort);
+		if (info->icount.rxshort)
+			ret += sprintf(buf+ret, " rxshort:%d", info->icount.rxshort);	
+		if (info->icount.rxlong)
+			ret += sprintf(buf+ret, " rxlong:%d", info->icount.rxlong);
+		if (info->icount.rxover)
+			ret += sprintf(buf+ret, " rxover:%d", info->icount.rxover);
+		if (info->icount.rxcrc)
+			ret += sprintf(buf+ret, " rxcrc:%d", info->icount.rxcrc);
+	} else {
+		ret += sprintf(buf+ret, " ASYNC tx:%d rx:%d",
+			      info->icount.tx, info->icount.rx);
+		if (info->icount.frame)
+			ret += sprintf(buf+ret, " fe:%d", info->icount.frame);
+		if (info->icount.parity)
+			ret += sprintf(buf+ret, " pe:%d", info->icount.parity);
+		if (info->icount.brk)
+			ret += sprintf(buf+ret, " brk:%d", info->icount.brk);	
+		if (info->icount.overrun)
+			ret += sprintf(buf+ret, " oe:%d", info->icount.overrun);
+	}
+	
+	/* Append serial signal status to end */
+	ret += sprintf(buf+ret, " %s\n", stat_buf+1);
+	
+	ret += sprintf(buf+ret, "txactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
+	 info->tx_active,info->bh_requested,info->bh_running,
+	 info->pending_bh);
+	 
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	{	
+	u16 Tcsr = usc_InReg( info, TCSR );
+	u16 Tdmr = usc_InDmaReg( info, TDMR );
+	u16 Ticr = usc_InReg( info, TICR );
+	u16 Rscr = usc_InReg( info, RCSR );
+	u16 Rdmr = usc_InDmaReg( info, RDMR );
+	u16 Ricr = usc_InReg( info, RICR );
+	u16 Icr = usc_InReg( info, ICR );
+	u16 Dccr = usc_InReg( info, DCCR );
+	u16 Tmr = usc_InReg( info, TMR );
+	u16 Tccr = usc_InReg( info, TCCR );
+	u16 Ccar = inw( info->io_base + CCAR );
+	ret += sprintf(buf+ret, "tcsr=%04X tdmr=%04X ticr=%04X rcsr=%04X rdmr=%04X\n"
+                        "ricr=%04X icr =%04X dccr=%04X tmr=%04X tccr=%04X ccar=%04X\n",
+	 		Tcsr,Tdmr,Ticr,Rscr,Rdmr,Ricr,Icr,Dccr,Tmr,Tccr,Ccar );
+	}
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+	return ret;
+	
+}	/* end of line_info() */
+
+/* mgsl_read_proc()
+ * 
+ * Called to print information about devices
+ * 
+ * Arguments:
+ * 	page	page of memory to hold returned info
+ * 	start	
+ * 	off
+ * 	count
+ * 	eof
+ * 	data
+ * 	
+ * Return Value:
+ */
+static int mgsl_read_proc(char *page, char **start, off_t off, int count,
+		 int *eof, void *data)
+{
+	int len = 0, l;
+	off_t	begin = 0;
+	struct mgsl_struct *info;
+	
+	len += sprintf(page, "synclink driver:%s\n", driver_version);
+	
+	info = mgsl_device_list;
+	while( info ) {
+		l = line_info(page + len, info);
+		len += l;
+		if (len+begin > off+count)
+			goto done;
+		if (len+begin < off) {
+			begin += len;
+			len = 0;
+		}
+		info = info->next_device;
+	}
+
+	*eof = 1;
+done:
+	if (off >= len+begin)
+		return 0;
+	*start = page + (off-begin);
+	return ((count < begin+len-off) ? count : begin+len-off);
+	
+}	/* end of mgsl_read_proc() */
+
+/* mgsl_allocate_dma_buffers()
+ * 
+ * 	Allocate and format DMA buffers (ISA adapter)
+ * 	or format shared memory buffers (PCI adapter).
+ * 
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	0 if success, otherwise error
+ */
+static int mgsl_allocate_dma_buffers(struct mgsl_struct *info)
+{
+	unsigned short BuffersPerFrame;
+
+	info->last_mem_alloc = 0;
+
+	/* Calculate the number of DMA buffers necessary to hold the */
+	/* largest allowable frame size. Note: If the max frame size is */
+	/* not an even multiple of the DMA buffer size then we need to */
+	/* round the buffer count per frame up one. */
+
+	BuffersPerFrame = (unsigned short)(info->max_frame_size/DMABUFFERSIZE);
+	if ( info->max_frame_size % DMABUFFERSIZE )
+		BuffersPerFrame++;
+
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI ) {
+		/*
+		 * The PCI adapter has 256KBytes of shared memory to use.
+		 * This is 64 PAGE_SIZE buffers.
+		 *
+		 * The first page is used for padding at this time so the
+		 * buffer list does not begin at offset 0 of the PCI
+		 * adapter's shared memory.
+		 *
+		 * The 2nd page is used for the buffer list. A 4K buffer
+		 * list can hold 128 DMA_BUFFER structures at 32 bytes
+		 * each.
+		 *
+		 * This leaves 62 4K pages.
+		 *
+		 * The next N pages are used for transmit frame(s). We
+		 * reserve enough 4K page blocks to hold the required
+		 * number of transmit dma buffers (num_tx_dma_buffers),
+		 * each of MaxFrameSize size.
+		 *
+		 * Of the remaining pages (62-N), determine how many can
+		 * be used to receive full MaxFrameSize inbound frames
+		 */
+		info->tx_buffer_count = info->num_tx_dma_buffers * BuffersPerFrame;
+		info->rx_buffer_count = 62 - info->tx_buffer_count;
+	} else {
+		/* Calculate the number of PAGE_SIZE buffers needed for */
+		/* receive and transmit DMA buffers. */
+
+
+		/* Calculate the number of DMA buffers necessary to */
+		/* hold 7 max size receive frames and one max size transmit frame. */
+		/* The receive buffer count is bumped by one so we avoid an */
+		/* End of List condition if all receive buffers are used when */
+		/* using linked list DMA buffers. */
+
+		info->tx_buffer_count = info->num_tx_dma_buffers * BuffersPerFrame;
+		info->rx_buffer_count = (BuffersPerFrame * MAXRXFRAMES) + 6;
+		
+		/* 
+		 * limit total TxBuffers & RxBuffers to 62 4K total 
+		 * (ala PCI Allocation) 
+		 */
+		
+		if ( (info->tx_buffer_count + info->rx_buffer_count) > 62 )
+			info->rx_buffer_count = 62 - info->tx_buffer_count;
+
+	}
+
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk("%s(%d):Allocating %d TX and %d RX DMA buffers.\n",
+			__FILE__,__LINE__, info->tx_buffer_count,info->rx_buffer_count);
+	
+	if ( mgsl_alloc_buffer_list_memory( info ) < 0 ||
+		  mgsl_alloc_frame_memory(info, info->rx_buffer_list, info->rx_buffer_count) < 0 || 
+		  mgsl_alloc_frame_memory(info, info->tx_buffer_list, info->tx_buffer_count) < 0 || 
+		  mgsl_alloc_intermediate_rxbuffer_memory(info) < 0  ||
+		  mgsl_alloc_intermediate_txbuffer_memory(info) < 0 ) {
+		printk("%s(%d):Can't allocate DMA buffer memory\n",__FILE__,__LINE__);
+		return -ENOMEM;
+	}
+	
+	mgsl_reset_rx_dma_buffers( info );
+  	mgsl_reset_tx_dma_buffers( info );
+
+	return 0;
+
+}	/* end of mgsl_allocate_dma_buffers() */
+
+/*
+ * mgsl_alloc_buffer_list_memory()
+ * 
+ * Allocate a common DMA buffer for use as the
+ * receive and transmit buffer lists.
+ * 
+ * A buffer list is a set of buffer entries where each entry contains
+ * a pointer to an actual buffer and a pointer to the next buffer entry
+ * (plus some other info about the buffer).
+ * 
+ * The buffer entries for a list are built to form a circular list so
+ * that when the entire list has been traversed you start back at the
+ * beginning.
+ * 
+ * This function allocates memory for just the buffer entries.
+ * The links (pointer to next entry) are filled in with the physical
+ * address of the next entry so the adapter can navigate the list
+ * using bus master DMA. The pointers to the actual buffers are filled
+ * out later when the actual buffers are allocated.
+ * 
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	0 if success, otherwise error
+ */
+static int mgsl_alloc_buffer_list_memory( struct mgsl_struct *info )
+{
+	unsigned int i;
+
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI ) {
+		/* PCI adapter uses shared memory. */
+		info->buffer_list = info->memory_base + info->last_mem_alloc;
+		info->buffer_list_phys = info->last_mem_alloc;
+		info->last_mem_alloc += BUFFERLISTSIZE;
+	} else {
+		/* ISA adapter uses system memory. */
+		/* The buffer lists are allocated as a common buffer that both */
+		/* the processor and adapter can access. This allows the driver to */
+		/* inspect portions of the buffer while other portions are being */
+		/* updated by the adapter using Bus Master DMA. */
+
+		info->buffer_list = kmalloc(BUFFERLISTSIZE, GFP_KERNEL | GFP_DMA);
+		if ( info->buffer_list == NULL )
+			return -ENOMEM;
+			
+		info->buffer_list_phys = isa_virt_to_bus(info->buffer_list);
+	}
+
+	/* We got the memory for the buffer entry lists. */
+	/* Initialize the memory block to all zeros. */
+	memset( info->buffer_list, 0, BUFFERLISTSIZE );
+
+	/* Save virtual address pointers to the receive and */
+	/* transmit buffer lists. (Receive 1st). These pointers will */
+	/* be used by the processor to access the lists. */
+	info->rx_buffer_list = (DMABUFFERENTRY *)info->buffer_list;
+	info->tx_buffer_list = (DMABUFFERENTRY *)info->buffer_list;
+	info->tx_buffer_list += info->rx_buffer_count;
+
+	/*
+	 * Build the links for the buffer entry lists such that
+	 * two circular lists are built. (Transmit and Receive).
+	 *
+	 * Note: the links are physical addresses
+	 * which are read by the adapter to determine the next
+	 * buffer entry to use.
+	 */
+
+	for ( i = 0; i < info->rx_buffer_count; i++ ) {
+		/* calculate and store physical address of this buffer entry */
+		info->rx_buffer_list[i].phys_entry =
+			info->buffer_list_phys + (i * sizeof(DMABUFFERENTRY));
+
+		/* calculate and store physical address of */
+		/* next entry in cirular list of entries */
+
+		info->rx_buffer_list[i].link = info->buffer_list_phys;
+
+		if ( i < info->rx_buffer_count - 1 )
+			info->rx_buffer_list[i].link += (i + 1) * sizeof(DMABUFFERENTRY);
+	}
+
+	for ( i = 0; i < info->tx_buffer_count; i++ ) {
+		/* calculate and store physical address of this buffer entry */
+		info->tx_buffer_list[i].phys_entry = info->buffer_list_phys +
+			((info->rx_buffer_count + i) * sizeof(DMABUFFERENTRY));
+
+		/* calculate and store physical address of */
+		/* next entry in cirular list of entries */
+
+		info->tx_buffer_list[i].link = info->buffer_list_phys +
+			info->rx_buffer_count * sizeof(DMABUFFERENTRY);
+
+		if ( i < info->tx_buffer_count - 1 )
+			info->tx_buffer_list[i].link += (i + 1) * sizeof(DMABUFFERENTRY);
+	}
+
+	return 0;
+
+}	/* end of mgsl_alloc_buffer_list_memory() */
+
+/* Free DMA buffers allocated for use as the
+ * receive and transmit buffer lists.
+ * Warning:
+ * 
+ * 	The data transfer buffers associated with the buffer list
+ * 	MUST be freed before freeing the buffer list itself because
+ * 	the buffer list contains the information necessary to free
+ * 	the individual buffers!
+ */
+static void mgsl_free_buffer_list_memory( struct mgsl_struct *info )
+{
+	if ( info->buffer_list && info->bus_type != MGSL_BUS_TYPE_PCI )
+		kfree(info->buffer_list);
+		
+	info->buffer_list = NULL;
+	info->rx_buffer_list = NULL;
+	info->tx_buffer_list = NULL;
+
+}	/* end of mgsl_free_buffer_list_memory() */
+
+/*
+ * mgsl_alloc_frame_memory()
+ * 
+ * 	Allocate the frame DMA buffers used by the specified buffer list.
+ * 	Each DMA buffer will be one memory page in size. This is necessary
+ * 	because memory can fragment enough that it may be impossible
+ * 	contiguous pages.
+ * 
+ * Arguments:
+ * 
+ *	info		pointer to device instance data
+ * 	BufferList	pointer to list of buffer entries
+ * 	Buffercount	count of buffer entries in buffer list
+ * 
+ * Return Value:	0 if success, otherwise -ENOMEM
+ */
+static int mgsl_alloc_frame_memory(struct mgsl_struct *info,DMABUFFERENTRY *BufferList,int Buffercount)
+{
+	int i;
+	unsigned long phys_addr;
+
+	/* Allocate page sized buffers for the receive buffer list */
+
+	for ( i = 0; i < Buffercount; i++ ) {
+		if ( info->bus_type == MGSL_BUS_TYPE_PCI ) {
+			/* PCI adapter uses shared memory buffers. */
+			BufferList[i].virt_addr = info->memory_base + info->last_mem_alloc;
+			phys_addr = info->last_mem_alloc;
+			info->last_mem_alloc += DMABUFFERSIZE;
+		} else {
+			/* ISA adapter uses system memory. */
+			BufferList[i].virt_addr = 
+				kmalloc(DMABUFFERSIZE, GFP_KERNEL | GFP_DMA);
+			if ( BufferList[i].virt_addr == NULL )
+				return -ENOMEM;
+			phys_addr = isa_virt_to_bus(BufferList[i].virt_addr);
+		}
+		BufferList[i].phys_addr = phys_addr;
+	}
+
+	return 0;
+
+}	/* end of mgsl_alloc_frame_memory() */
+
+/*
+ * mgsl_free_frame_memory()
+ * 
+ * 	Free the buffers associated with
+ * 	each buffer entry of a buffer list.
+ * 
+ * Arguments:
+ * 
+ *	info		pointer to device instance data
+ * 	BufferList	pointer to list of buffer entries
+ * 	Buffercount	count of buffer entries in buffer list
+ * 
+ * Return Value:	None
+ */
+static void mgsl_free_frame_memory(struct mgsl_struct *info, DMABUFFERENTRY *BufferList, int Buffercount)
+{
+	int i;
+
+	if ( BufferList ) {
+		for ( i = 0 ; i < Buffercount ; i++ ) {
+			if ( BufferList[i].virt_addr ) {
+				if ( info->bus_type != MGSL_BUS_TYPE_PCI )
+					kfree(BufferList[i].virt_addr);
+				BufferList[i].virt_addr = NULL;
+			}
+		}
+	}
+
+}	/* end of mgsl_free_frame_memory() */
+
+/* mgsl_free_dma_buffers()
+ * 
+ * 	Free DMA buffers
+ * 	
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_free_dma_buffers( struct mgsl_struct *info )
+{
+	mgsl_free_frame_memory( info, info->rx_buffer_list, info->rx_buffer_count );
+	mgsl_free_frame_memory( info, info->tx_buffer_list, info->tx_buffer_count );
+	mgsl_free_buffer_list_memory( info );
+
+}	/* end of mgsl_free_dma_buffers() */
+
+
+/*
+ * mgsl_alloc_intermediate_rxbuffer_memory()
+ * 
+ * 	Allocate a buffer large enough to hold max_frame_size. This buffer
+ *	is used to pass an assembled frame to the line discipline.
+ * 
+ * Arguments:
+ * 
+ *	info		pointer to device instance data
+ * 
+ * Return Value:	0 if success, otherwise -ENOMEM
+ */
+static int mgsl_alloc_intermediate_rxbuffer_memory(struct mgsl_struct *info)
+{
+	info->intermediate_rxbuffer = kmalloc(info->max_frame_size, GFP_KERNEL | GFP_DMA);
+	if ( info->intermediate_rxbuffer == NULL )
+		return -ENOMEM;
+
+	return 0;
+
+}	/* end of mgsl_alloc_intermediate_rxbuffer_memory() */
+
+/*
+ * mgsl_free_intermediate_rxbuffer_memory()
+ * 
+ * 
+ * Arguments:
+ * 
+ *	info		pointer to device instance data
+ * 
+ * Return Value:	None
+ */
+static void mgsl_free_intermediate_rxbuffer_memory(struct mgsl_struct *info)
+{
+	if ( info->intermediate_rxbuffer )
+		kfree(info->intermediate_rxbuffer);
+
+	info->intermediate_rxbuffer = NULL;
+
+}	/* end of mgsl_free_intermediate_rxbuffer_memory() */
+
+/*
+ * mgsl_alloc_intermediate_txbuffer_memory()
+ *
+ * 	Allocate intermdiate transmit buffer(s) large enough to hold max_frame_size.
+ * 	This buffer is used to load transmit frames into the adapter's dma transfer
+ * 	buffers when there is sufficient space.
+ *
+ * Arguments:
+ *
+ *	info		pointer to device instance data
+ *
+ * Return Value:	0 if success, otherwise -ENOMEM
+ */
+static int mgsl_alloc_intermediate_txbuffer_memory(struct mgsl_struct *info)
+{
+	int i;
+
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk("%s %s(%d)  allocating %d tx holding buffers\n",
+				info->device_name, __FILE__,__LINE__,info->num_tx_holding_buffers);
+
+	memset(info->tx_holding_buffers,0,sizeof(info->tx_holding_buffers));
+
+	for ( i=0; i<info->num_tx_holding_buffers; ++i) {
+		info->tx_holding_buffers[i].buffer =
+			kmalloc(info->max_frame_size, GFP_KERNEL);
+		if ( info->tx_holding_buffers[i].buffer == NULL )
+			return -ENOMEM;
+	}
+
+	return 0;
+
+}	/* end of mgsl_alloc_intermediate_txbuffer_memory() */
+
+/*
+ * mgsl_free_intermediate_txbuffer_memory()
+ *
+ *
+ * Arguments:
+ *
+ *	info		pointer to device instance data
+ *
+ * Return Value:	None
+ */
+static void mgsl_free_intermediate_txbuffer_memory(struct mgsl_struct *info)
+{
+	int i;
+
+	for ( i=0; i<info->num_tx_holding_buffers; ++i ) {
+		if ( info->tx_holding_buffers[i].buffer ) {
+				kfree(info->tx_holding_buffers[i].buffer);
+				info->tx_holding_buffers[i].buffer=NULL;
+		}
+	}
+
+	info->get_tx_holding_index = 0;
+	info->put_tx_holding_index = 0;
+	info->tx_holding_count = 0;
+
+}	/* end of mgsl_free_intermediate_txbuffer_memory() */
+
+
+/*
+ * load_next_tx_holding_buffer()
+ *
+ * attempts to load the next buffered tx request into the
+ * tx dma buffers
+ *
+ * Arguments:
+ *
+ *	info		pointer to device instance data
+ *
+ * Return Value:	1 if next buffered tx request loaded
+ * 			into adapter's tx dma buffer,
+ * 			0 otherwise
+ */
+static int load_next_tx_holding_buffer(struct mgsl_struct *info)
+{
+	int ret = 0;
+
+	if ( info->tx_holding_count ) {
+		/* determine if we have enough tx dma buffers
+		 * to accommodate the next tx frame
+		 */
+		struct tx_holding_buffer *ptx =
+			&info->tx_holding_buffers[info->get_tx_holding_index];
+		int num_free = num_free_tx_dma_buffers(info);
+		int num_needed = ptx->buffer_size / DMABUFFERSIZE;
+		if ( ptx->buffer_size % DMABUFFERSIZE )
+			++num_needed;
+
+		if (num_needed <= num_free) {
+			info->xmit_cnt = ptx->buffer_size;
+			mgsl_load_tx_dma_buffer(info,ptx->buffer,ptx->buffer_size);
+
+			--info->tx_holding_count;
+			if ( ++info->get_tx_holding_index >= info->num_tx_holding_buffers)
+				info->get_tx_holding_index=0;
+
+			/* restart transmit timer */
+			mod_timer(&info->tx_timer, jiffies + msecs_to_jiffies(5000));
+
+			ret = 1;
+		}
+	}
+
+	return ret;
+}
+
+/*
+ * save_tx_buffer_request()
+ *
+ * attempt to store transmit frame request for later transmission
+ *
+ * Arguments:
+ *
+ *	info		pointer to device instance data
+ * 	Buffer		pointer to buffer containing frame to load
+ * 	BufferSize	size in bytes of frame in Buffer
+ *
+ * Return Value:	1 if able to store, 0 otherwise
+ */
+static int save_tx_buffer_request(struct mgsl_struct *info,const char *Buffer, unsigned int BufferSize)
+{
+	struct tx_holding_buffer *ptx;
+
+	if ( info->tx_holding_count >= info->num_tx_holding_buffers ) {
+		return 0;	        /* all buffers in use */
+	}
+
+	ptx = &info->tx_holding_buffers[info->put_tx_holding_index];
+	ptx->buffer_size = BufferSize;
+	memcpy( ptx->buffer, Buffer, BufferSize);
+
+	++info->tx_holding_count;
+	if ( ++info->put_tx_holding_index >= info->num_tx_holding_buffers)
+		info->put_tx_holding_index=0;
+
+	return 1;
+}
+
+static int mgsl_claim_resources(struct mgsl_struct *info)
+{
+	if (request_region(info->io_base,info->io_addr_size,"synclink") == NULL) {
+		printk( "%s(%d):I/O address conflict on device %s Addr=%08X\n",
+			__FILE__,__LINE__,info->device_name, info->io_base);
+		return -ENODEV;
+	}
+	info->io_addr_requested = 1;
+	
+	if ( request_irq(info->irq_level,mgsl_interrupt,info->irq_flags,
+		info->device_name, info ) < 0 ) {
+		printk( "%s(%d):Cant request interrupt on device %s IRQ=%d\n",
+			__FILE__,__LINE__,info->device_name, info->irq_level );
+		goto errout;
+	}
+	info->irq_requested = 1;
+	
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI ) {
+		if (request_mem_region(info->phys_memory_base,0x40000,"synclink") == NULL) {
+			printk( "%s(%d):mem addr conflict device %s Addr=%08X\n",
+				__FILE__,__LINE__,info->device_name, info->phys_memory_base);
+			goto errout;
+		}
+		info->shared_mem_requested = 1;
+		if (request_mem_region(info->phys_lcr_base + info->lcr_offset,128,"synclink") == NULL) {
+			printk( "%s(%d):lcr mem addr conflict device %s Addr=%08X\n",
+				__FILE__,__LINE__,info->device_name, info->phys_lcr_base + info->lcr_offset);
+			goto errout;
+		}
+		info->lcr_mem_requested = 1;
+
+		info->memory_base = ioremap(info->phys_memory_base,0x40000);
+		if (!info->memory_base) {
+			printk( "%s(%d):Cant map shared memory on device %s MemAddr=%08X\n",
+				__FILE__,__LINE__,info->device_name, info->phys_memory_base );
+			goto errout;
+		}
+		
+		if ( !mgsl_memory_test(info) ) {
+			printk( "%s(%d):Failed shared memory test %s MemAddr=%08X\n",
+				__FILE__,__LINE__,info->device_name, info->phys_memory_base );
+			goto errout;
+		}
+		
+		info->lcr_base = ioremap(info->phys_lcr_base,PAGE_SIZE) + info->lcr_offset;
+		if (!info->lcr_base) {
+			printk( "%s(%d):Cant map LCR memory on device %s MemAddr=%08X\n",
+				__FILE__,__LINE__,info->device_name, info->phys_lcr_base );
+			goto errout;
+		}
+		
+	} else {
+		/* claim DMA channel */
+		
+		if (request_dma(info->dma_level,info->device_name) < 0){
+			printk( "%s(%d):Cant request DMA channel on device %s DMA=%d\n",
+				__FILE__,__LINE__,info->device_name, info->dma_level );
+			mgsl_release_resources( info );
+			return -ENODEV;
+		}
+		info->dma_requested = 1;
+
+		/* ISA adapter uses bus master DMA */		
+		set_dma_mode(info->dma_level,DMA_MODE_CASCADE);
+		enable_dma(info->dma_level);
+	}
+	
+	if ( mgsl_allocate_dma_buffers(info) < 0 ) {
+		printk( "%s(%d):Cant allocate DMA buffers on device %s DMA=%d\n",
+			__FILE__,__LINE__,info->device_name, info->dma_level );
+		goto errout;
+	}	
+	
+	return 0;
+errout:
+	mgsl_release_resources(info);
+	return -ENODEV;
+
+}	/* end of mgsl_claim_resources() */
+
+static void mgsl_release_resources(struct mgsl_struct *info)
+{
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):mgsl_release_resources(%s) entry\n",
+			__FILE__,__LINE__,info->device_name );
+			
+	if ( info->irq_requested ) {
+		free_irq(info->irq_level, info);
+		info->irq_requested = 0;
+	}
+	if ( info->dma_requested ) {
+		disable_dma(info->dma_level);
+		free_dma(info->dma_level);
+		info->dma_requested = 0;
+	}
+	mgsl_free_dma_buffers(info);
+	mgsl_free_intermediate_rxbuffer_memory(info);
+     	mgsl_free_intermediate_txbuffer_memory(info);
+	
+	if ( info->io_addr_requested ) {
+		release_region(info->io_base,info->io_addr_size);
+		info->io_addr_requested = 0;
+	}
+	if ( info->shared_mem_requested ) {
+		release_mem_region(info->phys_memory_base,0x40000);
+		info->shared_mem_requested = 0;
+	}
+	if ( info->lcr_mem_requested ) {
+		release_mem_region(info->phys_lcr_base + info->lcr_offset,128);
+		info->lcr_mem_requested = 0;
+	}
+	if (info->memory_base){
+		iounmap(info->memory_base);
+		info->memory_base = NULL;
+	}
+	if (info->lcr_base){
+		iounmap(info->lcr_base - info->lcr_offset);
+		info->lcr_base = NULL;
+	}
+	
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):mgsl_release_resources(%s) exit\n",
+			__FILE__,__LINE__,info->device_name );
+			
+}	/* end of mgsl_release_resources() */
+
+/* mgsl_add_device()
+ * 
+ * 	Add the specified device instance data structure to the
+ * 	global linked list of devices and increment the device count.
+ * 	
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_add_device( struct mgsl_struct *info )
+{
+	info->next_device = NULL;
+	info->line = mgsl_device_count;
+	sprintf(info->device_name,"ttySL%d",info->line);
+	
+	if (info->line < MAX_TOTAL_DEVICES) {
+		if (maxframe[info->line])
+			info->max_frame_size = maxframe[info->line];
+		info->dosyncppp = dosyncppp[info->line];
+
+		if (txdmabufs[info->line]) {
+			info->num_tx_dma_buffers = txdmabufs[info->line];
+			if (info->num_tx_dma_buffers < 1)
+				info->num_tx_dma_buffers = 1;
+		}
+
+		if (txholdbufs[info->line]) {
+			info->num_tx_holding_buffers = txholdbufs[info->line];
+			if (info->num_tx_holding_buffers < 1)
+				info->num_tx_holding_buffers = 1;
+			else if (info->num_tx_holding_buffers > MAX_TX_HOLDING_BUFFERS)
+				info->num_tx_holding_buffers = MAX_TX_HOLDING_BUFFERS;
+		}
+	}
+
+	mgsl_device_count++;
+	
+	if ( !mgsl_device_list )
+		mgsl_device_list = info;
+	else {	
+		struct mgsl_struct *current_dev = mgsl_device_list;
+		while( current_dev->next_device )
+			current_dev = current_dev->next_device;
+		current_dev->next_device = info;
+	}
+	
+	if ( info->max_frame_size < 4096 )
+		info->max_frame_size = 4096;
+	else if ( info->max_frame_size > 65535 )
+		info->max_frame_size = 65535;
+	
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI ) {
+		printk( "SyncLink PCI v%d %s: IO=%04X IRQ=%d Mem=%08X,%08X MaxFrameSize=%u\n",
+			info->hw_version + 1, info->device_name, info->io_base, info->irq_level,
+			info->phys_memory_base, info->phys_lcr_base,
+		     	info->max_frame_size );
+	} else {
+		printk( "SyncLink ISA %s: IO=%04X IRQ=%d DMA=%d MaxFrameSize=%u\n",
+			info->device_name, info->io_base, info->irq_level, info->dma_level,
+		     	info->max_frame_size );
+	}
+
+#ifdef CONFIG_HDLC
+	hdlcdev_init(info);
+#endif
+
+}	/* end of mgsl_add_device() */
+
+/* mgsl_allocate_device()
+ * 
+ * 	Allocate and initialize a device instance structure
+ * 	
+ * Arguments:		none
+ * Return Value:	pointer to mgsl_struct if success, otherwise NULL
+ */
+static struct mgsl_struct* mgsl_allocate_device(void)
+{
+	struct mgsl_struct *info;
+	
+	info = (struct mgsl_struct *)kmalloc(sizeof(struct mgsl_struct),
+		 GFP_KERNEL);
+		 
+	if (!info) {
+		printk("Error can't allocate device instance data\n");
+	} else {
+		memset(info, 0, sizeof(struct mgsl_struct));
+		info->magic = MGSL_MAGIC;
+		INIT_WORK(&info->task, mgsl_bh_handler, info);
+		info->max_frame_size = 4096;
+		info->close_delay = 5*HZ/10;
+		info->closing_wait = 30*HZ;
+		init_waitqueue_head(&info->open_wait);
+		init_waitqueue_head(&info->close_wait);
+		init_waitqueue_head(&info->status_event_wait_q);
+		init_waitqueue_head(&info->event_wait_q);
+		spin_lock_init(&info->irq_spinlock);
+		spin_lock_init(&info->netlock);
+		memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
+		info->idle_mode = HDLC_TXIDLE_FLAGS;		
+		info->num_tx_dma_buffers = 1;
+		info->num_tx_holding_buffers = 0;
+	}
+	
+	return info;
+
+}	/* end of mgsl_allocate_device()*/
+
+static struct tty_operations mgsl_ops = {
+	.open = mgsl_open,
+	.close = mgsl_close,
+	.write = mgsl_write,
+	.put_char = mgsl_put_char,
+	.flush_chars = mgsl_flush_chars,
+	.write_room = mgsl_write_room,
+	.chars_in_buffer = mgsl_chars_in_buffer,
+	.flush_buffer = mgsl_flush_buffer,
+	.ioctl = mgsl_ioctl,
+	.throttle = mgsl_throttle,
+	.unthrottle = mgsl_unthrottle,
+	.send_xchar = mgsl_send_xchar,
+	.break_ctl = mgsl_break,
+	.wait_until_sent = mgsl_wait_until_sent,
+ 	.read_proc = mgsl_read_proc,
+	.set_termios = mgsl_set_termios,
+	.stop = mgsl_stop,
+	.start = mgsl_start,
+	.hangup = mgsl_hangup,
+	.tiocmget = tiocmget,
+	.tiocmset = tiocmset,
+};
+
+/*
+ * perform tty device initialization
+ */
+static int mgsl_init_tty(void)
+{
+	int rc;
+
+	serial_driver = alloc_tty_driver(128);
+	if (!serial_driver)
+		return -ENOMEM;
+	
+	serial_driver->owner = THIS_MODULE;
+	serial_driver->driver_name = "synclink";
+	serial_driver->name = "ttySL";
+	serial_driver->major = ttymajor;
+	serial_driver->minor_start = 64;
+	serial_driver->type = TTY_DRIVER_TYPE_SERIAL;
+	serial_driver->subtype = SERIAL_TYPE_NORMAL;
+	serial_driver->init_termios = tty_std_termios;
+	serial_driver->init_termios.c_cflag =
+		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+	serial_driver->flags = TTY_DRIVER_REAL_RAW;
+	tty_set_operations(serial_driver, &mgsl_ops);
+	if ((rc = tty_register_driver(serial_driver)) < 0) {
+		printk("%s(%d):Couldn't register serial driver\n",
+			__FILE__,__LINE__);
+		put_tty_driver(serial_driver);
+		serial_driver = NULL;
+		return rc;
+	}
+			
+ 	printk("%s %s, tty major#%d\n",
+		driver_name, driver_version,
+		serial_driver->major);
+	return 0;
+}
+
+/* enumerate user specified ISA adapters
+ */
+static void mgsl_enum_isa_devices(void)
+{
+	struct mgsl_struct *info;
+	int i;
+		
+	/* Check for user specified ISA devices */
+	
+	for (i=0 ;(i < MAX_ISA_DEVICES) && io[i] && irq[i]; i++){
+		if ( debug_level >= DEBUG_LEVEL_INFO )
+			printk("ISA device specified io=%04X,irq=%d,dma=%d\n",
+				io[i], irq[i], dma[i] );
+		
+		info = mgsl_allocate_device();
+		if ( !info ) {
+			/* error allocating device instance data */
+			if ( debug_level >= DEBUG_LEVEL_ERROR )
+				printk( "can't allocate device instance data.\n");
+			continue;
+		}
+		
+		/* Copy user configuration info to device instance data */
+		info->io_base = (unsigned int)io[i];
+		info->irq_level = (unsigned int)irq[i];
+		info->irq_level = irq_canonicalize(info->irq_level);
+		info->dma_level = (unsigned int)dma[i];
+		info->bus_type = MGSL_BUS_TYPE_ISA;
+		info->io_addr_size = 16;
+		info->irq_flags = 0;
+		
+		mgsl_add_device( info );
+	}
+}
+
+static void synclink_cleanup(void)
+{
+	int rc;
+	struct mgsl_struct *info;
+	struct mgsl_struct *tmp;
+
+	printk("Unloading %s: %s\n", driver_name, driver_version);
+
+	if (serial_driver) {
+		if ((rc = tty_unregister_driver(serial_driver)))
+			printk("%s(%d) failed to unregister tty driver err=%d\n",
+			       __FILE__,__LINE__,rc);
+		put_tty_driver(serial_driver);
+	}
+
+	info = mgsl_device_list;
+	while(info) {
+#ifdef CONFIG_HDLC
+		hdlcdev_exit(info);
+#endif
+		mgsl_release_resources(info);
+		tmp = info;
+		info = info->next_device;
+		kfree(tmp);
+	}
+	
+	if (tmp_buf) {
+		free_page((unsigned long) tmp_buf);
+		tmp_buf = NULL;
+	}
+	
+	if (pci_registered)
+		pci_unregister_driver(&synclink_pci_driver);
+}
+
+static int __init synclink_init(void)
+{
+	int rc;
+
+	if (break_on_load) {
+	 	mgsl_get_text_ptr();
+  		BREAKPOINT();
+	}
+
+ 	printk("%s %s\n", driver_name, driver_version);
+
+	mgsl_enum_isa_devices();
+	if ((rc = pci_register_driver(&synclink_pci_driver)) < 0)
+		printk("%s:failed to register PCI driver, error=%d\n",__FILE__,rc);
+	else
+		pci_registered = 1;
+
+	if ((rc = mgsl_init_tty()) < 0)
+		goto error;
+
+	return 0;
+
+error:
+	synclink_cleanup();
+	return rc;
+}
+
+static void __exit synclink_exit(void)
+{
+	synclink_cleanup();
+}
+
+module_init(synclink_init);
+module_exit(synclink_exit);
+
+/*
+ * usc_RTCmd()
+ *
+ * Issue a USC Receive/Transmit command to the
+ * Channel Command/Address Register (CCAR).
+ *
+ * Notes:
+ *
+ *    The command is encoded in the most significant 5 bits <15..11>
+ *    of the CCAR value. Bits <10..7> of the CCAR must be preserved
+ *    and Bits <6..0> must be written as zeros.
+ *
+ * Arguments:
+ *
+ *    info   pointer to device information structure
+ *    Cmd    command mask (use symbolic macros)
+ *
+ * Return Value:
+ *
+ *    None
+ */
+static void usc_RTCmd( struct mgsl_struct *info, u16 Cmd )
+{
+	/* output command to CCAR in bits <15..11> */
+	/* preserve bits <10..7>, bits <6..0> must be zero */
+
+	outw( Cmd + info->loopback_bits, info->io_base + CCAR );
+
+	/* Read to flush write to CCAR */
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+		inw( info->io_base + CCAR );
+
+}	/* end of usc_RTCmd() */
+
+/*
+ * usc_DmaCmd()
+ *
+ *    Issue a DMA command to the DMA Command/Address Register (DCAR).
+ *
+ * Arguments:
+ *
+ *    info   pointer to device information structure
+ *    Cmd    DMA command mask (usc_DmaCmd_XX Macros)
+ *
+ * Return Value:
+ *
+ *       None
+ */
+static void usc_DmaCmd( struct mgsl_struct *info, u16 Cmd )
+{
+	/* write command mask to DCAR */
+	outw( Cmd + info->mbre_bit, info->io_base );
+
+	/* Read to flush write to DCAR */
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+		inw( info->io_base );
+
+}	/* end of usc_DmaCmd() */
+
+/*
+ * usc_OutDmaReg()
+ *
+ *    Write a 16-bit value to a USC DMA register
+ *
+ * Arguments:
+ *
+ *    info      pointer to device info structure
+ *    RegAddr   register address (number) for write
+ *    RegValue  16-bit value to write to register
+ *
+ * Return Value:
+ *
+ *    None
+ *
+ */
+static void usc_OutDmaReg( struct mgsl_struct *info, u16 RegAddr, u16 RegValue )
+{
+	/* Note: The DCAR is located at the adapter base address */
+	/* Note: must preserve state of BIT8 in DCAR */
+
+	outw( RegAddr + info->mbre_bit, info->io_base );
+	outw( RegValue, info->io_base );
+
+	/* Read to flush write to DCAR */
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+		inw( info->io_base );
+
+}	/* end of usc_OutDmaReg() */
+ 
+/*
+ * usc_InDmaReg()
+ *
+ *    Read a 16-bit value from a DMA register
+ *
+ * Arguments:
+ *
+ *    info     pointer to device info structure
+ *    RegAddr  register address (number) to read from
+ *
+ * Return Value:
+ *
+ *    The 16-bit value read from register
+ *
+ */
+static u16 usc_InDmaReg( struct mgsl_struct *info, u16 RegAddr )
+{
+	/* Note: The DCAR is located at the adapter base address */
+	/* Note: must preserve state of BIT8 in DCAR */
+
+	outw( RegAddr + info->mbre_bit, info->io_base );
+	return inw( info->io_base );
+
+}	/* end of usc_InDmaReg() */
+
+/*
+ *
+ * usc_OutReg()
+ *
+ *    Write a 16-bit value to a USC serial channel register 
+ *
+ * Arguments:
+ *
+ *    info      pointer to device info structure
+ *    RegAddr   register address (number) to write to
+ *    RegValue  16-bit value to write to register
+ *
+ * Return Value:
+ *
+ *    None
+ *
+ */
+static void usc_OutReg( struct mgsl_struct *info, u16 RegAddr, u16 RegValue )
+{
+	outw( RegAddr + info->loopback_bits, info->io_base + CCAR );
+	outw( RegValue, info->io_base + CCAR );
+
+	/* Read to flush write to CCAR */
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+		inw( info->io_base + CCAR );
+
+}	/* end of usc_OutReg() */
+
+/*
+ * usc_InReg()
+ *
+ *    Reads a 16-bit value from a USC serial channel register
+ *
+ * Arguments:
+ *
+ *    info       pointer to device extension
+ *    RegAddr    register address (number) to read from
+ *
+ * Return Value:
+ *
+ *    16-bit value read from register
+ */
+static u16 usc_InReg( struct mgsl_struct *info, u16 RegAddr )
+{
+	outw( RegAddr + info->loopback_bits, info->io_base + CCAR );
+	return inw( info->io_base + CCAR );
+
+}	/* end of usc_InReg() */
+
+/* usc_set_sdlc_mode()
+ *
+ *    Set up the adapter for SDLC DMA communications.
+ *
+ * Arguments:		info    pointer to device instance data
+ * Return Value: 	NONE
+ */
+static void usc_set_sdlc_mode( struct mgsl_struct *info )
+{
+	u16 RegValue;
+	int PreSL1660;
+	
+	/*
+	 * determine if the IUSC on the adapter is pre-SL1660. If
+	 * not, take advantage of the UnderWait feature of more
+	 * modern chips. If an underrun occurs and this bit is set,
+	 * the transmitter will idle the programmed idle pattern
+	 * until the driver has time to service the underrun. Otherwise,
+	 * the dma controller may get the cycles previously requested
+	 * and begin transmitting queued tx data.
+	 */
+	usc_OutReg(info,TMCR,0x1f);
+	RegValue=usc_InReg(info,TMDR);
+	if ( RegValue == IUSC_PRE_SL1660 )
+		PreSL1660 = 1;
+	else
+		PreSL1660 = 0;
+	
+
+ 	if ( info->params.flags & HDLC_FLAG_HDLC_LOOPMODE )
+ 	{
+ 	   /*
+ 	   ** Channel Mode Register (CMR)
+ 	   **
+ 	   ** <15..14>    10    Tx Sub Modes, Send Flag on Underrun
+ 	   ** <13>        0     0 = Transmit Disabled (initially)
+ 	   ** <12>        0     1 = Consecutive Idles share common 0
+ 	   ** <11..8>     1110  Transmitter Mode = HDLC/SDLC Loop
+ 	   ** <7..4>      0000  Rx Sub Modes, addr/ctrl field handling
+ 	   ** <3..0>      0110  Receiver Mode = HDLC/SDLC
+ 	   **
+ 	   ** 1000 1110 0000 0110 = 0x8e06
+ 	   */
+ 	   RegValue = 0x8e06;
+ 
+ 	   /*--------------------------------------------------
+ 	    * ignore user options for UnderRun Actions and
+ 	    * preambles
+ 	    *--------------------------------------------------*/
+ 	}
+ 	else
+ 	{	
+		/* Channel mode Register (CMR)
+		 *
+		 * <15..14>  00    Tx Sub modes, Underrun Action
+		 * <13>      0     1 = Send Preamble before opening flag
+		 * <12>      0     1 = Consecutive Idles share common 0
+		 * <11..8>   0110  Transmitter mode = HDLC/SDLC
+		 * <7..4>    0000  Rx Sub modes, addr/ctrl field handling
+		 * <3..0>    0110  Receiver mode = HDLC/SDLC
+		 *
+		 * 0000 0110 0000 0110 = 0x0606
+		 */
+		if (info->params.mode == MGSL_MODE_RAW) {
+			RegValue = 0x0001;		/* Set Receive mode = external sync */
+
+			usc_OutReg( info, IOCR,		/* Set IOCR DCD is RxSync Detect Input */
+				(unsigned short)((usc_InReg(info, IOCR) & ~(BIT13|BIT12)) | BIT12));
+
+			/*
+			 * TxSubMode:
+			 * 	CMR <15>		0	Don't send CRC on Tx Underrun
+			 * 	CMR <14>		x	undefined
+			 * 	CMR <13>		0	Send preamble before openning sync
+			 * 	CMR <12>		0	Send 8-bit syncs, 1=send Syncs per TxLength
+			 *
+			 * TxMode:
+			 * 	CMR <11-8)	0100	MonoSync
+			 *
+			 * 	0x00 0100 xxxx xxxx  04xx
+			 */
+			RegValue |= 0x0400;
+		}
+		else {
+
+		RegValue = 0x0606;
+
+		if ( info->params.flags & HDLC_FLAG_UNDERRUN_ABORT15 )
+			RegValue |= BIT14;
+		else if ( info->params.flags & HDLC_FLAG_UNDERRUN_FLAG )
+			RegValue |= BIT15;
+		else if ( info->params.flags & HDLC_FLAG_UNDERRUN_CRC )
+			RegValue |= BIT15 + BIT14;
+		}
+
+		if ( info->params.preamble != HDLC_PREAMBLE_PATTERN_NONE )
+			RegValue |= BIT13;
+	}
+
+	if ( info->params.mode == MGSL_MODE_HDLC &&
+		(info->params.flags & HDLC_FLAG_SHARE_ZERO) )
+		RegValue |= BIT12;
+
+	if ( info->params.addr_filter != 0xff )
+	{
+		/* set up receive address filtering */
+		usc_OutReg( info, RSR, info->params.addr_filter );
+		RegValue |= BIT4;
+	}
+
+	usc_OutReg( info, CMR, RegValue );
+	info->cmr_value = RegValue;
+
+	/* Receiver mode Register (RMR)
+	 *
+	 * <15..13>  000    encoding
+	 * <12..11>  00     FCS = 16bit CRC CCITT (x15 + x12 + x5 + 1)
+	 * <10>      1      1 = Set CRC to all 1s (use for SDLC/HDLC)
+	 * <9>       0      1 = Include Receive chars in CRC
+	 * <8>       1      1 = Use Abort/PE bit as abort indicator
+	 * <7..6>    00     Even parity
+	 * <5>       0      parity disabled
+	 * <4..2>    000    Receive Char Length = 8 bits
+	 * <1..0>    00     Disable Receiver
+	 *
+	 * 0000 0101 0000 0000 = 0x0500
+	 */
+
+	RegValue = 0x0500;
+
+	switch ( info->params.encoding ) {
+	case HDLC_ENCODING_NRZB:               RegValue |= BIT13; break;
+	case HDLC_ENCODING_NRZI_MARK:          RegValue |= BIT14; break;
+	case HDLC_ENCODING_NRZI_SPACE:	       RegValue |= BIT14 + BIT13; break;
+	case HDLC_ENCODING_BIPHASE_MARK:       RegValue |= BIT15; break;
+	case HDLC_ENCODING_BIPHASE_SPACE:      RegValue |= BIT15 + BIT13; break;
+	case HDLC_ENCODING_BIPHASE_LEVEL:      RegValue |= BIT15 + BIT14; break;
+	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT15 + BIT14 + BIT13; break;
+	}
+
+	if ( (info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_16_CCITT )
+		RegValue |= BIT9;
+	else if ( (info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_32_CCITT )
+		RegValue |= ( BIT12 | BIT10 | BIT9 );
+
+	usc_OutReg( info, RMR, RegValue );
+
+	/* Set the Receive count Limit Register (RCLR) to 0xffff. */
+	/* When an opening flag of an SDLC frame is recognized the */
+	/* Receive Character count (RCC) is loaded with the value in */
+	/* RCLR. The RCC is decremented for each received byte.  The */
+	/* value of RCC is stored after the closing flag of the frame */
+	/* allowing the frame size to be computed. */
+
+	usc_OutReg( info, RCLR, RCLRVALUE );
+
+	usc_RCmd( info, RCmd_SelectRicrdma_level );
+
+	/* Receive Interrupt Control Register (RICR)
+	 *
+	 * <15..8>	?	RxFIFO DMA Request Level
+	 * <7>		0	Exited Hunt IA (Interrupt Arm)
+	 * <6>		0	Idle Received IA
+	 * <5>		0	Break/Abort IA
+	 * <4>		0	Rx Bound IA
+	 * <3>		1	Queued status reflects oldest 2 bytes in FIFO
+	 * <2>		0	Abort/PE IA
+	 * <1>		1	Rx Overrun IA
+	 * <0>		0	Select TC0 value for readback
+	 *
+	 *	0000 0000 0000 1000 = 0x000a
+	 */
+
+	/* Carry over the Exit Hunt and Idle Received bits */
+	/* in case they have been armed by usc_ArmEvents.   */
+
+	RegValue = usc_InReg( info, RICR ) & 0xc0;
+
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+		usc_OutReg( info, RICR, (u16)(0x030a | RegValue) );
+	else
+		usc_OutReg( info, RICR, (u16)(0x140a | RegValue) );
+
+	/* Unlatch all Rx status bits and clear Rx status IRQ Pending */
+
+	usc_UnlatchRxstatusBits( info, RXSTATUS_ALL );
+	usc_ClearIrqPendingBits( info, RECEIVE_STATUS );
+
+	/* Transmit mode Register (TMR)
+	 *	
+	 * <15..13>	000	encoding
+	 * <12..11>	00	FCS = 16bit CRC CCITT (x15 + x12 + x5 + 1)
+	 * <10>		1	1 = Start CRC as all 1s (use for SDLC/HDLC)
+	 * <9>		0	1 = Tx CRC Enabled
+	 * <8>		0	1 = Append CRC to end of transmit frame
+	 * <7..6>	00	Transmit parity Even
+	 * <5>		0	Transmit parity Disabled
+	 * <4..2>	000	Tx Char Length = 8 bits
+	 * <1..0>	00	Disable Transmitter
+	 *
+	 * 	0000 0100 0000 0000 = 0x0400
+	 */
+
+	RegValue = 0x0400;
+
+	switch ( info->params.encoding ) {
+	case HDLC_ENCODING_NRZB:               RegValue |= BIT13; break;
+	case HDLC_ENCODING_NRZI_MARK:          RegValue |= BIT14; break;
+	case HDLC_ENCODING_NRZI_SPACE:         RegValue |= BIT14 + BIT13; break;
+	case HDLC_ENCODING_BIPHASE_MARK:       RegValue |= BIT15; break;
+	case HDLC_ENCODING_BIPHASE_SPACE:      RegValue |= BIT15 + BIT13; break;
+	case HDLC_ENCODING_BIPHASE_LEVEL:      RegValue |= BIT15 + BIT14; break;
+	case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT15 + BIT14 + BIT13; break;
+	}
+
+	if ( (info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_16_CCITT )
+		RegValue |= BIT9 + BIT8;
+	else if ( (info->params.crc_type & HDLC_CRC_MASK) == HDLC_CRC_32_CCITT )
+		RegValue |= ( BIT12 | BIT10 | BIT9 | BIT8);
+
+	usc_OutReg( info, TMR, RegValue );
+
+	usc_set_txidle( info );
+
+
+	usc_TCmd( info, TCmd_SelectTicrdma_level );
+
+	/* Transmit Interrupt Control Register (TICR)
+	 *
+	 * <15..8>	?	Transmit FIFO DMA Level
+	 * <7>		0	Present IA (Interrupt Arm)
+	 * <6>		0	Idle Sent IA
+	 * <5>		1	Abort Sent IA
+	 * <4>		1	EOF/EOM Sent IA
+	 * <3>		0	CRC Sent IA
+	 * <2>		1	1 = Wait for SW Trigger to Start Frame
+	 * <1>		1	Tx Underrun IA
+	 * <0>		0	TC0 constant on read back
+	 *
+	 *	0000 0000 0011 0110 = 0x0036
+	 */
+
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+		usc_OutReg( info, TICR, 0x0736 );
+	else								
+		usc_OutReg( info, TICR, 0x1436 );
+
+	usc_UnlatchTxstatusBits( info, TXSTATUS_ALL );
+	usc_ClearIrqPendingBits( info, TRANSMIT_STATUS );
+
+	/*
+	** Transmit Command/Status Register (TCSR)
+	**
+	** <15..12>	0000	TCmd
+	** <11> 	0/1	UnderWait
+	** <10..08>	000	TxIdle
+	** <7>		x	PreSent
+	** <6>         	x	IdleSent
+	** <5>         	x	AbortSent
+	** <4>         	x	EOF/EOM Sent
+	** <3>         	x	CRC Sent
+	** <2>         	x	All Sent
+	** <1>         	x	TxUnder
+	** <0>         	x	TxEmpty
+	** 
+	** 0000 0000 0000 0000 = 0x0000
+	*/
+	info->tcsr_value = 0;
+
+	if ( !PreSL1660 )
+		info->tcsr_value |= TCSR_UNDERWAIT;
+		
+	usc_OutReg( info, TCSR, info->tcsr_value );
+
+	/* Clock mode Control Register (CMCR)
+	 *
+	 * <15..14>	00	counter 1 Source = Disabled
+	 * <13..12> 	00	counter 0 Source = Disabled
+	 * <11..10> 	11	BRG1 Input is TxC Pin
+	 * <9..8>	11	BRG0 Input is TxC Pin
+	 * <7..6>	01	DPLL Input is BRG1 Output
+	 * <5..3>	XXX	TxCLK comes from Port 0
+	 * <2..0>   	XXX	RxCLK comes from Port 1
+	 *
+	 *	0000 1111 0111 0111 = 0x0f77
+	 */
+
+	RegValue = 0x0f40;
+
+	if ( info->params.flags & HDLC_FLAG_RXC_DPLL )
+		RegValue |= 0x0003;	/* RxCLK from DPLL */
+	else if ( info->params.flags & HDLC_FLAG_RXC_BRG )
+		RegValue |= 0x0004;	/* RxCLK from BRG0 */
+ 	else if ( info->params.flags & HDLC_FLAG_RXC_TXCPIN)
+ 		RegValue |= 0x0006;	/* RxCLK from TXC Input */
+	else
+		RegValue |= 0x0007;	/* RxCLK from Port1 */
+
+	if ( info->params.flags & HDLC_FLAG_TXC_DPLL )
+		RegValue |= 0x0018;	/* TxCLK from DPLL */
+	else if ( info->params.flags & HDLC_FLAG_TXC_BRG )
+		RegValue |= 0x0020;	/* TxCLK from BRG0 */
+ 	else if ( info->params.flags & HDLC_FLAG_TXC_RXCPIN)
+ 		RegValue |= 0x0038;	/* RxCLK from TXC Input */
+	else
+		RegValue |= 0x0030;	/* TxCLK from Port0 */
+
+	usc_OutReg( info, CMCR, RegValue );
+
+
+	/* Hardware Configuration Register (HCR)
+	 *
+	 * <15..14>	00	CTR0 Divisor:00=32,01=16,10=8,11=4
+	 * <13>		0	CTR1DSel:0=CTR0Div determines CTR0Div
+	 * <12>		0	CVOK:0=report code violation in biphase
+	 * <11..10>	00	DPLL Divisor:00=32,01=16,10=8,11=4
+	 * <9..8>	XX	DPLL mode:00=disable,01=NRZ,10=Biphase,11=Biphase Level
+	 * <7..6>	00	reserved
+	 * <5>		0	BRG1 mode:0=continuous,1=single cycle
+	 * <4>		X	BRG1 Enable
+	 * <3..2>	00	reserved
+	 * <1>		0	BRG0 mode:0=continuous,1=single cycle
+	 * <0>		0	BRG0 Enable
+	 */
+
+	RegValue = 0x0000;
+
+	if ( info->params.flags & (HDLC_FLAG_RXC_DPLL + HDLC_FLAG_TXC_DPLL) ) {
+		u32 XtalSpeed;
+		u32 DpllDivisor;
+		u16 Tc;
+
+		/*  DPLL is enabled. Use BRG1 to provide continuous reference clock  */
+		/*  for DPLL. DPLL mode in HCR is dependent on the encoding used. */
+
+		if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+			XtalSpeed = 11059200;
+		else
+			XtalSpeed = 14745600;
+
+		if ( info->params.flags & HDLC_FLAG_DPLL_DIV16 ) {
+			DpllDivisor = 16;
+			RegValue |= BIT10;
+		}
+		else if ( info->params.flags & HDLC_FLAG_DPLL_DIV8 ) {
+			DpllDivisor = 8;
+			RegValue |= BIT11;
+		}
+		else
+			DpllDivisor = 32;
+
+		/*  Tc = (Xtal/Speed) - 1 */
+		/*  If twice the remainder of (Xtal/Speed) is greater than Speed */
+		/*  then rounding up gives a more precise time constant. Instead */
+		/*  of rounding up and then subtracting 1 we just don't subtract */
+		/*  the one in this case. */
+
+ 		/*--------------------------------------------------
+ 		 * ejz: for DPLL mode, application should use the
+ 		 * same clock speed as the partner system, even 
+ 		 * though clocking is derived from the input RxData.
+ 		 * In case the user uses a 0 for the clock speed,
+ 		 * default to 0xffffffff and don't try to divide by
+ 		 * zero
+ 		 *--------------------------------------------------*/
+ 		if ( info->params.clock_speed )
+ 		{
+			Tc = (u16)((XtalSpeed/DpllDivisor)/info->params.clock_speed);
+			if ( !((((XtalSpeed/DpllDivisor) % info->params.clock_speed) * 2)
+			       / info->params.clock_speed) )
+				Tc--;
+ 		}
+ 		else
+ 			Tc = -1;
+ 				  
+
+		/* Write 16-bit Time Constant for BRG1 */
+		usc_OutReg( info, TC1R, Tc );
+
+		RegValue |= BIT4;		/* enable BRG1 */
+
+		switch ( info->params.encoding ) {
+		case HDLC_ENCODING_NRZ:
+		case HDLC_ENCODING_NRZB:
+		case HDLC_ENCODING_NRZI_MARK:
+		case HDLC_ENCODING_NRZI_SPACE: RegValue |= BIT8; break;
+		case HDLC_ENCODING_BIPHASE_MARK:
+		case HDLC_ENCODING_BIPHASE_SPACE: RegValue |= BIT9; break;
+		case HDLC_ENCODING_BIPHASE_LEVEL:
+		case HDLC_ENCODING_DIFF_BIPHASE_LEVEL: RegValue |= BIT9 + BIT8; break;
+		}
+	}
+
+	usc_OutReg( info, HCR, RegValue );
+
+
+	/* Channel Control/status Register (CCSR)
+	 *
+	 * <15>		X	RCC FIFO Overflow status (RO)
+	 * <14>		X	RCC FIFO Not Empty status (RO)
+	 * <13>		0	1 = Clear RCC FIFO (WO)
+	 * <12>		X	DPLL Sync (RW)
+	 * <11>		X	DPLL 2 Missed Clocks status (RO)
+	 * <10>		X	DPLL 1 Missed Clock status (RO)
+	 * <9..8>	00	DPLL Resync on rising and falling edges (RW)
+	 * <7>		X	SDLC Loop On status (RO)
+	 * <6>		X	SDLC Loop Send status (RO)
+	 * <5>		1	Bypass counters for TxClk and RxClk (RW)
+	 * <4..2>   	000	Last Char of SDLC frame has 8 bits (RW)
+	 * <1..0>   	00	reserved
+	 *
+	 *	0000 0000 0010 0000 = 0x0020
+	 */
+
+	usc_OutReg( info, CCSR, 0x1020 );
+
+
+	if ( info->params.flags & HDLC_FLAG_AUTO_CTS ) {
+		usc_OutReg( info, SICR,
+			    (u16)(usc_InReg(info,SICR) | SICR_CTS_INACTIVE) );
+	}
+	
+
+	/* enable Master Interrupt Enable bit (MIE) */
+	usc_EnableMasterIrqBit( info );
+
+	usc_ClearIrqPendingBits( info, RECEIVE_STATUS + RECEIVE_DATA +
+				TRANSMIT_STATUS + TRANSMIT_DATA + MISC);
+
+	/* arm RCC underflow interrupt */
+	usc_OutReg(info, SICR, (u16)(usc_InReg(info,SICR) | BIT3));
+	usc_EnableInterrupts(info, MISC);
+
+	info->mbre_bit = 0;
+	outw( 0, info->io_base ); 			/* clear Master Bus Enable (DCAR) */
+	usc_DmaCmd( info, DmaCmd_ResetAllChannels );	/* disable both DMA channels */
+	info->mbre_bit = BIT8;
+	outw( BIT8, info->io_base );			/* set Master Bus Enable (DCAR) */
+
+	if (info->bus_type == MGSL_BUS_TYPE_ISA) {
+		/* Enable DMAEN (Port 7, Bit 14) */
+		/* This connects the DMA request signal to the ISA bus */
+		usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT15) & ~BIT14));
+	}
+
+	/* DMA Control Register (DCR)
+	 *
+	 * <15..14>	10	Priority mode = Alternating Tx/Rx
+	 *		01	Rx has priority
+	 *		00	Tx has priority
+	 *
+	 * <13>		1	Enable Priority Preempt per DCR<15..14>
+	 *			(WARNING DCR<11..10> must be 00 when this is 1)
+	 *		0	Choose activate channel per DCR<11..10>
+	 *
+	 * <12>		0	Little Endian for Array/List
+	 * <11..10>	00	Both Channels can use each bus grant
+	 * <9..6>	0000	reserved
+	 * <5>		0	7 CLK - Minimum Bus Re-request Interval
+	 * <4>		0	1 = drive D/C and S/D pins
+	 * <3>		1	1 = Add one wait state to all DMA cycles.
+	 * <2>		0	1 = Strobe /UAS on every transfer.
+	 * <1..0>	11	Addr incrementing only affects LS24 bits
+	 *
+	 *	0110 0000 0000 1011 = 0x600b
+	 */
+
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI ) {
+		/* PCI adapter does not need DMA wait state */
+		usc_OutDmaReg( info, DCR, 0xa00b );
+	}
+	else
+		usc_OutDmaReg( info, DCR, 0x800b );
+
+
+	/* Receive DMA mode Register (RDMR)
+	 *
+	 * <15..14>	11	DMA mode = Linked List Buffer mode
+	 * <13>		1	RSBinA/L = store Rx status Block in Arrary/List entry
+	 * <12>		1	Clear count of List Entry after fetching
+	 * <11..10>	00	Address mode = Increment
+	 * <9>		1	Terminate Buffer on RxBound
+	 * <8>		0	Bus Width = 16bits
+	 * <7..0>	?	status Bits (write as 0s)
+	 *
+	 * 1111 0010 0000 0000 = 0xf200
+	 */
+
+	usc_OutDmaReg( info, RDMR, 0xf200 );
+
+
+	/* Transmit DMA mode Register (TDMR)
+	 *
+	 * <15..14>	11	DMA mode = Linked List Buffer mode
+	 * <13>		1	TCBinA/L = fetch Tx Control Block from List entry
+	 * <12>		1	Clear count of List Entry after fetching
+	 * <11..10>	00	Address mode = Increment
+	 * <9>		1	Terminate Buffer on end of frame
+	 * <8>		0	Bus Width = 16bits
+	 * <7..0>	?	status Bits (Read Only so write as 0)
+	 *
+	 *	1111 0010 0000 0000 = 0xf200
+	 */
+
+	usc_OutDmaReg( info, TDMR, 0xf200 );
+
+
+	/* DMA Interrupt Control Register (DICR)
+	 *
+	 * <15>		1	DMA Interrupt Enable
+	 * <14>		0	1 = Disable IEO from USC
+	 * <13>		0	1 = Don't provide vector during IntAck
+	 * <12>		1	1 = Include status in Vector
+	 * <10..2>	0	reserved, Must be 0s
+	 * <1>		0	1 = Rx DMA Interrupt Enabled
+	 * <0>		0	1 = Tx DMA Interrupt Enabled
+	 *
+	 *	1001 0000 0000 0000 = 0x9000
+	 */
+
+	usc_OutDmaReg( info, DICR, 0x9000 );
+
+	usc_InDmaReg( info, RDMR );		/* clear pending receive DMA IRQ bits */
+	usc_InDmaReg( info, TDMR );		/* clear pending transmit DMA IRQ bits */
+	usc_OutDmaReg( info, CDIR, 0x0303 );	/* clear IUS and Pending for Tx and Rx */
+
+	/* Channel Control Register (CCR)
+	 *
+	 * <15..14>	10	Use 32-bit Tx Control Blocks (TCBs)
+	 * <13>		0	Trigger Tx on SW Command Disabled
+	 * <12>		0	Flag Preamble Disabled
+	 * <11..10>	00	Preamble Length
+	 * <9..8>	00	Preamble Pattern
+	 * <7..6>	10	Use 32-bit Rx status Blocks (RSBs)
+	 * <5>		0	Trigger Rx on SW Command Disabled
+	 * <4..0>	0	reserved
+	 *
+	 *	1000 0000 1000 0000 = 0x8080
+	 */
+
+	RegValue = 0x8080;
+
+	switch ( info->params.preamble_length ) {
+	case HDLC_PREAMBLE_LENGTH_16BITS: RegValue |= BIT10; break;
+	case HDLC_PREAMBLE_LENGTH_32BITS: RegValue |= BIT11; break;
+	case HDLC_PREAMBLE_LENGTH_64BITS: RegValue |= BIT11 + BIT10; break;
+	}
+
+	switch ( info->params.preamble ) {
+	case HDLC_PREAMBLE_PATTERN_FLAGS: RegValue |= BIT8 + BIT12; break;
+	case HDLC_PREAMBLE_PATTERN_ONES:  RegValue |= BIT8; break;
+	case HDLC_PREAMBLE_PATTERN_10:    RegValue |= BIT9; break;
+	case HDLC_PREAMBLE_PATTERN_01:    RegValue |= BIT9 + BIT8; break;
+	}
+
+	usc_OutReg( info, CCR, RegValue );
+
+
+	/*
+	 * Burst/Dwell Control Register
+	 *
+	 * <15..8>	0x20	Maximum number of transfers per bus grant
+	 * <7..0>	0x00	Maximum number of clock cycles per bus grant
+	 */
+
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI ) {
+		/* don't limit bus occupancy on PCI adapter */
+		usc_OutDmaReg( info, BDCR, 0x0000 );
+	}
+	else
+		usc_OutDmaReg( info, BDCR, 0x2000 );
+
+	usc_stop_transmitter(info);
+	usc_stop_receiver(info);
+	
+}	/* end of usc_set_sdlc_mode() */
+
+/* usc_enable_loopback()
+ *
+ * Set the 16C32 for internal loopback mode.
+ * The TxCLK and RxCLK signals are generated from the BRG0 and
+ * the TxD is looped back to the RxD internally.
+ *
+ * Arguments:		info	pointer to device instance data
+ *			enable	1 = enable loopback, 0 = disable
+ * Return Value:	None
+ */
+static void usc_enable_loopback(struct mgsl_struct *info, int enable)
+{
+	if (enable) {
+		/* blank external TXD output */
+		usc_OutReg(info,IOCR,usc_InReg(info,IOCR) | (BIT7+BIT6));
+	
+		/* Clock mode Control Register (CMCR)
+		 *
+		 * <15..14>	00	counter 1 Disabled
+		 * <13..12> 	00	counter 0 Disabled
+		 * <11..10> 	11	BRG1 Input is TxC Pin
+		 * <9..8>	11	BRG0 Input is TxC Pin
+		 * <7..6>	01	DPLL Input is BRG1 Output
+		 * <5..3>	100	TxCLK comes from BRG0
+		 * <2..0>   	100	RxCLK comes from BRG0
+		 *
+		 * 0000 1111 0110 0100 = 0x0f64
+		 */
+
+		usc_OutReg( info, CMCR, 0x0f64 );
+
+		/* Write 16-bit Time Constant for BRG0 */
+		/* use clock speed if available, otherwise use 8 for diagnostics */
+		if (info->params.clock_speed) {
+			if (info->bus_type == MGSL_BUS_TYPE_PCI)
+				usc_OutReg(info, TC0R, (u16)((11059200/info->params.clock_speed)-1));
+			else
+				usc_OutReg(info, TC0R, (u16)((14745600/info->params.clock_speed)-1));
+		} else
+			usc_OutReg(info, TC0R, (u16)8);
+
+		/* Hardware Configuration Register (HCR) Clear Bit 1, BRG0
+		   mode = Continuous Set Bit 0 to enable BRG0.  */
+		usc_OutReg( info, HCR, (u16)((usc_InReg( info, HCR ) & ~BIT1) | BIT0) );
+
+		/* Input/Output Control Reg, <2..0> = 100, Drive RxC pin with BRG0 */
+		usc_OutReg(info, IOCR, (u16)((usc_InReg(info, IOCR) & 0xfff8) | 0x0004));
+
+		/* set Internal Data loopback mode */
+		info->loopback_bits = 0x300;
+		outw( 0x0300, info->io_base + CCAR );
+	} else {
+		/* enable external TXD output */
+		usc_OutReg(info,IOCR,usc_InReg(info,IOCR) & ~(BIT7+BIT6));
+	
+		/* clear Internal Data loopback mode */
+		info->loopback_bits = 0;
+		outw( 0,info->io_base + CCAR );
+	}
+	
+}	/* end of usc_enable_loopback() */
+
+/* usc_enable_aux_clock()
+ *
+ * Enabled the AUX clock output at the specified frequency.
+ *
+ * Arguments:
+ *
+ *	info		pointer to device extension
+ *	data_rate	data rate of clock in bits per second
+ *			A data rate of 0 disables the AUX clock.
+ *
+ * Return Value:	None
+ */
+static void usc_enable_aux_clock( struct mgsl_struct *info, u32 data_rate )
+{
+	u32 XtalSpeed;
+	u16 Tc;
+
+	if ( data_rate ) {
+		if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+			XtalSpeed = 11059200;
+		else
+			XtalSpeed = 14745600;
+
+
+		/* Tc = (Xtal/Speed) - 1 */
+		/* If twice the remainder of (Xtal/Speed) is greater than Speed */
+		/* then rounding up gives a more precise time constant. Instead */
+		/* of rounding up and then subtracting 1 we just don't subtract */
+		/* the one in this case. */
+
+
+		Tc = (u16)(XtalSpeed/data_rate);
+		if ( !(((XtalSpeed % data_rate) * 2) / data_rate) )
+			Tc--;
+
+		/* Write 16-bit Time Constant for BRG0 */
+		usc_OutReg( info, TC0R, Tc );
+
+		/*
+		 * Hardware Configuration Register (HCR)
+		 * Clear Bit 1, BRG0 mode = Continuous
+		 * Set Bit 0 to enable BRG0.
+		 */
+
+		usc_OutReg( info, HCR, (u16)((usc_InReg( info, HCR ) & ~BIT1) | BIT0) );
+
+		/* Input/Output Control Reg, <2..0> = 100, Drive RxC pin with BRG0 */
+		usc_OutReg( info, IOCR, (u16)((usc_InReg(info, IOCR) & 0xfff8) | 0x0004) );
+	} else {
+		/* data rate == 0 so turn off BRG0 */
+		usc_OutReg( info, HCR, (u16)(usc_InReg( info, HCR ) & ~BIT0) );
+	}
+
+}	/* end of usc_enable_aux_clock() */
+
+/*
+ *
+ * usc_process_rxoverrun_sync()
+ *
+ *		This function processes a receive overrun by resetting the
+ *		receive DMA buffers and issuing a Purge Rx FIFO command
+ *		to allow the receiver to continue receiving.
+ *
+ * Arguments:
+ *
+ *	info		pointer to device extension
+ *
+ * Return Value: None
+ */
+static void usc_process_rxoverrun_sync( struct mgsl_struct *info )
+{
+	int start_index;
+	int end_index;
+	int frame_start_index;
+	int start_of_frame_found = FALSE;
+	int end_of_frame_found = FALSE;
+	int reprogram_dma = FALSE;
+
+	DMABUFFERENTRY *buffer_list = info->rx_buffer_list;
+	u32 phys_addr;
+
+	usc_DmaCmd( info, DmaCmd_PauseRxChannel );
+	usc_RCmd( info, RCmd_EnterHuntmode );
+	usc_RTCmd( info, RTCmd_PurgeRxFifo );
+
+	/* CurrentRxBuffer points to the 1st buffer of the next */
+	/* possibly available receive frame. */
+	
+	frame_start_index = start_index = end_index = info->current_rx_buffer;
+
+	/* Search for an unfinished string of buffers. This means */
+	/* that a receive frame started (at least one buffer with */
+	/* count set to zero) but there is no terminiting buffer */
+	/* (status set to non-zero). */
+
+	while( !buffer_list[end_index].count )
+	{
+		/* Count field has been reset to zero by 16C32. */
+		/* This buffer is currently in use. */
+
+		if ( !start_of_frame_found )
+		{
+			start_of_frame_found = TRUE;
+			frame_start_index = end_index;
+			end_of_frame_found = FALSE;
+		}
+
+		if ( buffer_list[end_index].status )
+		{
+			/* Status field has been set by 16C32. */
+			/* This is the last buffer of a received frame. */
+
+			/* We want to leave the buffers for this frame intact. */
+			/* Move on to next possible frame. */
+
+			start_of_frame_found = FALSE;
+			end_of_frame_found = TRUE;
+		}
+
+  		/* advance to next buffer entry in linked list */
+  		end_index++;
+  		if ( end_index == info->rx_buffer_count )
+  			end_index = 0;
+
+		if ( start_index == end_index )
+		{
+			/* The entire list has been searched with all Counts == 0 and */
+			/* all Status == 0. The receive buffers are */
+			/* completely screwed, reset all receive buffers! */
+			mgsl_reset_rx_dma_buffers( info );
+			frame_start_index = 0;
+			start_of_frame_found = FALSE;
+			reprogram_dma = TRUE;
+			break;
+		}
+	}
+
+	if ( start_of_frame_found && !end_of_frame_found )
+	{
+		/* There is an unfinished string of receive DMA buffers */
+		/* as a result of the receiver overrun. */
+
+		/* Reset the buffers for the unfinished frame */
+		/* and reprogram the receive DMA controller to start */
+		/* at the 1st buffer of unfinished frame. */
+
+		start_index = frame_start_index;
+
+		do
+		{
+			*((unsigned long *)&(info->rx_buffer_list[start_index++].count)) = DMABUFFERSIZE;
+
+  			/* Adjust index for wrap around. */
+  			if ( start_index == info->rx_buffer_count )
+  				start_index = 0;
+
+		} while( start_index != end_index );
+
+		reprogram_dma = TRUE;
+	}
+
+	if ( reprogram_dma )
+	{
+		usc_UnlatchRxstatusBits(info,RXSTATUS_ALL);
+		usc_ClearIrqPendingBits(info, RECEIVE_DATA|RECEIVE_STATUS);
+		usc_UnlatchRxstatusBits(info, RECEIVE_DATA|RECEIVE_STATUS);
+		
+		usc_EnableReceiver(info,DISABLE_UNCONDITIONAL);
+		
+		/* This empties the receive FIFO and loads the RCC with RCLR */
+		usc_OutReg( info, CCSR, (u16)(usc_InReg(info,CCSR) | BIT13) );
+
+		/* program 16C32 with physical address of 1st DMA buffer entry */
+		phys_addr = info->rx_buffer_list[frame_start_index].phys_entry;
+		usc_OutDmaReg( info, NRARL, (u16)phys_addr );
+		usc_OutDmaReg( info, NRARU, (u16)(phys_addr >> 16) );
+
+		usc_UnlatchRxstatusBits( info, RXSTATUS_ALL );
+		usc_ClearIrqPendingBits( info, RECEIVE_DATA + RECEIVE_STATUS );
+		usc_EnableInterrupts( info, RECEIVE_STATUS );
+
+		/* 1. Arm End of Buffer (EOB) Receive DMA Interrupt (BIT2 of RDIAR) */
+		/* 2. Enable Receive DMA Interrupts (BIT1 of DICR) */
+
+		usc_OutDmaReg( info, RDIAR, BIT3 + BIT2 );
+		usc_OutDmaReg( info, DICR, (u16)(usc_InDmaReg(info,DICR) | BIT1) );
+		usc_DmaCmd( info, DmaCmd_InitRxChannel );
+		if ( info->params.flags & HDLC_FLAG_AUTO_DCD )
+			usc_EnableReceiver(info,ENABLE_AUTO_DCD);
+		else
+			usc_EnableReceiver(info,ENABLE_UNCONDITIONAL);
+	}
+	else
+	{
+		/* This empties the receive FIFO and loads the RCC with RCLR */
+		usc_OutReg( info, CCSR, (u16)(usc_InReg(info,CCSR) | BIT13) );
+		usc_RTCmd( info, RTCmd_PurgeRxFifo );
+	}
+
+}	/* end of usc_process_rxoverrun_sync() */
+
+/* usc_stop_receiver()
+ *
+ *	Disable USC receiver
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_stop_receiver( struct mgsl_struct *info )
+{
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):usc_stop_receiver(%s)\n",
+			 __FILE__,__LINE__, info->device_name );
+			 
+	/* Disable receive DMA channel. */
+	/* This also disables receive DMA channel interrupts */
+	usc_DmaCmd( info, DmaCmd_ResetRxChannel );
+
+	usc_UnlatchRxstatusBits( info, RXSTATUS_ALL );
+	usc_ClearIrqPendingBits( info, RECEIVE_DATA + RECEIVE_STATUS );
+	usc_DisableInterrupts( info, RECEIVE_DATA + RECEIVE_STATUS );
+
+	usc_EnableReceiver(info,DISABLE_UNCONDITIONAL);
+
+	/* This empties the receive FIFO and loads the RCC with RCLR */
+	usc_OutReg( info, CCSR, (u16)(usc_InReg(info,CCSR) | BIT13) );
+	usc_RTCmd( info, RTCmd_PurgeRxFifo );
+
+	info->rx_enabled = 0;
+	info->rx_overflow = 0;
+	info->rx_rcc_underrun = 0;
+	
+}	/* end of stop_receiver() */
+
+/* usc_start_receiver()
+ *
+ *	Enable the USC receiver 
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_start_receiver( struct mgsl_struct *info )
+{
+	u32 phys_addr;
+	
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):usc_start_receiver(%s)\n",
+			 __FILE__,__LINE__, info->device_name );
+
+	mgsl_reset_rx_dma_buffers( info );
+	usc_stop_receiver( info );
+
+	usc_OutReg( info, CCSR, (u16)(usc_InReg(info,CCSR) | BIT13) );
+	usc_RTCmd( info, RTCmd_PurgeRxFifo );
+
+	if ( info->params.mode == MGSL_MODE_HDLC ||
+		info->params.mode == MGSL_MODE_RAW ) {
+		/* DMA mode Transfers */
+		/* Program the DMA controller. */
+		/* Enable the DMA controller end of buffer interrupt. */
+
+		/* program 16C32 with physical address of 1st DMA buffer entry */
+		phys_addr = info->rx_buffer_list[0].phys_entry;
+		usc_OutDmaReg( info, NRARL, (u16)phys_addr );
+		usc_OutDmaReg( info, NRARU, (u16)(phys_addr >> 16) );
+
+		usc_UnlatchRxstatusBits( info, RXSTATUS_ALL );
+		usc_ClearIrqPendingBits( info, RECEIVE_DATA + RECEIVE_STATUS );
+		usc_EnableInterrupts( info, RECEIVE_STATUS );
+
+		/* 1. Arm End of Buffer (EOB) Receive DMA Interrupt (BIT2 of RDIAR) */
+		/* 2. Enable Receive DMA Interrupts (BIT1 of DICR) */
+
+		usc_OutDmaReg( info, RDIAR, BIT3 + BIT2 );
+		usc_OutDmaReg( info, DICR, (u16)(usc_InDmaReg(info,DICR) | BIT1) );
+		usc_DmaCmd( info, DmaCmd_InitRxChannel );
+		if ( info->params.flags & HDLC_FLAG_AUTO_DCD )
+			usc_EnableReceiver(info,ENABLE_AUTO_DCD);
+		else
+			usc_EnableReceiver(info,ENABLE_UNCONDITIONAL);
+	} else {
+		usc_UnlatchRxstatusBits(info, RXSTATUS_ALL);
+		usc_ClearIrqPendingBits(info, RECEIVE_DATA + RECEIVE_STATUS);
+		usc_EnableInterrupts(info, RECEIVE_DATA);
+
+		usc_RTCmd( info, RTCmd_PurgeRxFifo );
+		usc_RCmd( info, RCmd_EnterHuntmode );
+
+		usc_EnableReceiver(info,ENABLE_UNCONDITIONAL);
+	}
+
+	usc_OutReg( info, CCSR, 0x1020 );
+
+	info->rx_enabled = 1;
+
+}	/* end of usc_start_receiver() */
+
+/* usc_start_transmitter()
+ *
+ *	Enable the USC transmitter and send a transmit frame if
+ *	one is loaded in the DMA buffers.
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_start_transmitter( struct mgsl_struct *info )
+{
+	u32 phys_addr;
+	unsigned int FrameSize;
+
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):usc_start_transmitter(%s)\n",
+			 __FILE__,__LINE__, info->device_name );
+			 
+	if ( info->xmit_cnt ) {
+
+		/* If auto RTS enabled and RTS is inactive, then assert */
+		/* RTS and set a flag indicating that the driver should */
+		/* negate RTS when the transmission completes. */
+
+		info->drop_rts_on_tx_done = 0;
+
+		if ( info->params.flags & HDLC_FLAG_AUTO_RTS ) {
+			usc_get_serial_signals( info );
+			if ( !(info->serial_signals & SerialSignal_RTS) ) {
+				info->serial_signals |= SerialSignal_RTS;
+				usc_set_serial_signals( info );
+				info->drop_rts_on_tx_done = 1;
+			}
+		}
+
+
+		if ( info->params.mode == MGSL_MODE_ASYNC ) {
+			if ( !info->tx_active ) {
+				usc_UnlatchTxstatusBits(info, TXSTATUS_ALL);
+				usc_ClearIrqPendingBits(info, TRANSMIT_STATUS + TRANSMIT_DATA);
+				usc_EnableInterrupts(info, TRANSMIT_DATA);
+				usc_load_txfifo(info);
+			}
+		} else {
+			/* Disable transmit DMA controller while programming. */
+			usc_DmaCmd( info, DmaCmd_ResetTxChannel );
+			
+			/* Transmit DMA buffer is loaded, so program USC */
+			/* to send the frame contained in the buffers.	 */
+
+			FrameSize = info->tx_buffer_list[info->start_tx_dma_buffer].rcc;
+
+			/* if operating in Raw sync mode, reset the rcc component
+			 * of the tx dma buffer entry, otherwise, the serial controller
+			 * will send a closing sync char after this count.
+			 */
+	    		if ( info->params.mode == MGSL_MODE_RAW )
+				info->tx_buffer_list[info->start_tx_dma_buffer].rcc = 0;
+
+			/* Program the Transmit Character Length Register (TCLR) */
+			/* and clear FIFO (TCC is loaded with TCLR on FIFO clear) */
+			usc_OutReg( info, TCLR, (u16)FrameSize );
+
+			usc_RTCmd( info, RTCmd_PurgeTxFifo );
+
+			/* Program the address of the 1st DMA Buffer Entry in linked list */
+			phys_addr = info->tx_buffer_list[info->start_tx_dma_buffer].phys_entry;
+			usc_OutDmaReg( info, NTARL, (u16)phys_addr );
+			usc_OutDmaReg( info, NTARU, (u16)(phys_addr >> 16) );
+
+			usc_UnlatchTxstatusBits( info, TXSTATUS_ALL );
+			usc_ClearIrqPendingBits( info, TRANSMIT_STATUS );
+			usc_EnableInterrupts( info, TRANSMIT_STATUS );
+
+			if ( info->params.mode == MGSL_MODE_RAW &&
+					info->num_tx_dma_buffers > 1 ) {
+			   /* When running external sync mode, attempt to 'stream' transmit  */
+			   /* by filling tx dma buffers as they become available. To do this */
+			   /* we need to enable Tx DMA EOB Status interrupts :               */
+			   /*                                                                */
+			   /* 1. Arm End of Buffer (EOB) Transmit DMA Interrupt (BIT2 of TDIAR) */
+			   /* 2. Enable Transmit DMA Interrupts (BIT0 of DICR) */
+
+			   usc_OutDmaReg( info, TDIAR, BIT2|BIT3 );
+			   usc_OutDmaReg( info, DICR, (u16)(usc_InDmaReg(info,DICR) | BIT0) );
+			}
+
+			/* Initialize Transmit DMA Channel */
+			usc_DmaCmd( info, DmaCmd_InitTxChannel );
+			
+			usc_TCmd( info, TCmd_SendFrame );
+			
+			info->tx_timer.expires = jiffies + msecs_to_jiffies(5000);
+			add_timer(&info->tx_timer);	
+		}
+		info->tx_active = 1;
+	}
+
+	if ( !info->tx_enabled ) {
+		info->tx_enabled = 1;
+		if ( info->params.flags & HDLC_FLAG_AUTO_CTS )
+			usc_EnableTransmitter(info,ENABLE_AUTO_CTS);
+		else
+			usc_EnableTransmitter(info,ENABLE_UNCONDITIONAL);
+	}
+
+}	/* end of usc_start_transmitter() */
+
+/* usc_stop_transmitter()
+ *
+ *	Stops the transmitter and DMA
+ *
+ * Arguments:		info	pointer to device isntance data
+ * Return Value:	None
+ */
+static void usc_stop_transmitter( struct mgsl_struct *info )
+{
+	if (debug_level >= DEBUG_LEVEL_ISR)
+		printk("%s(%d):usc_stop_transmitter(%s)\n",
+			 __FILE__,__LINE__, info->device_name );
+			 
+	del_timer(&info->tx_timer);	
+			 
+	usc_UnlatchTxstatusBits( info, TXSTATUS_ALL );
+	usc_ClearIrqPendingBits( info, TRANSMIT_STATUS + TRANSMIT_DATA );
+	usc_DisableInterrupts( info, TRANSMIT_STATUS + TRANSMIT_DATA );
+
+	usc_EnableTransmitter(info,DISABLE_UNCONDITIONAL);
+	usc_DmaCmd( info, DmaCmd_ResetTxChannel );
+	usc_RTCmd( info, RTCmd_PurgeTxFifo );
+
+	info->tx_enabled = 0;
+	info->tx_active  = 0;
+
+}	/* end of usc_stop_transmitter() */
+
+/* usc_load_txfifo()
+ *
+ *	Fill the transmit FIFO until the FIFO is full or
+ *	there is no more data to load.
+ *
+ * Arguments:		info	pointer to device extension (instance data)
+ * Return Value:	None
+ */
+static void usc_load_txfifo( struct mgsl_struct *info )
+{
+	int Fifocount;
+	u8 TwoBytes[2];
+	
+	if ( !info->xmit_cnt && !info->x_char )
+		return; 
+		
+	/* Select transmit FIFO status readback in TICR */
+	usc_TCmd( info, TCmd_SelectTicrTxFifostatus );
+
+	/* load the Transmit FIFO until FIFOs full or all data sent */
+
+	while( (Fifocount = usc_InReg(info, TICR) >> 8) && info->xmit_cnt ) {
+		/* there is more space in the transmit FIFO and */
+		/* there is more data in transmit buffer */
+
+		if ( (info->xmit_cnt > 1) && (Fifocount > 1) && !info->x_char ) {
+ 			/* write a 16-bit word from transmit buffer to 16C32 */
+				
+			TwoBytes[0] = info->xmit_buf[info->xmit_tail++];
+			info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
+			TwoBytes[1] = info->xmit_buf[info->xmit_tail++];
+			info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
+			
+			outw( *((u16 *)TwoBytes), info->io_base + DATAREG);
+				
+			info->xmit_cnt -= 2;
+			info->icount.tx += 2;
+		} else {
+			/* only 1 byte left to transmit or 1 FIFO slot left */
+			
+			outw( (inw( info->io_base + CCAR) & 0x0780) | (TDR+LSBONLY),
+				info->io_base + CCAR );
+			
+			if (info->x_char) {
+				/* transmit pending high priority char */
+				outw( info->x_char,info->io_base + CCAR );
+				info->x_char = 0;
+			} else {
+				outw( info->xmit_buf[info->xmit_tail++],info->io_base + CCAR );
+				info->xmit_tail = info->xmit_tail & (SERIAL_XMIT_SIZE-1);
+				info->xmit_cnt--;
+			}
+			info->icount.tx++;
+		}
+	}
+
+}	/* end of usc_load_txfifo() */
+
+/* usc_reset()
+ *
+ *	Reset the adapter to a known state and prepare it for further use.
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_reset( struct mgsl_struct *info )
+{
+	if ( info->bus_type == MGSL_BUS_TYPE_PCI ) {
+		int i;
+		u32 readval;
+
+		/* Set BIT30 of Misc Control Register */
+		/* (Local Control Register 0x50) to force reset of USC. */
+
+		volatile u32 *MiscCtrl = (u32 *)(info->lcr_base + 0x50);
+		u32 *LCR0BRDR = (u32 *)(info->lcr_base + 0x28);
+
+		info->misc_ctrl_value |= BIT30;
+		*MiscCtrl = info->misc_ctrl_value;
+
+		/*
+		 * Force at least 170ns delay before clearing 
+		 * reset bit. Each read from LCR takes at least 
+		 * 30ns so 10 times for 300ns to be safe.
+		 */
+		for(i=0;i<10;i++)
+			readval = *MiscCtrl;
+
+		info->misc_ctrl_value &= ~BIT30;
+		*MiscCtrl = info->misc_ctrl_value;
+
+		*LCR0BRDR = BUS_DESCRIPTOR(
+			1,		// Write Strobe Hold (0-3)
+			2,		// Write Strobe Delay (0-3)
+			2,		// Read Strobe Delay  (0-3)
+			0,		// NWDD (Write data-data) (0-3)
+			4,		// NWAD (Write Addr-data) (0-31)
+			0,		// NXDA (Read/Write Data-Addr) (0-3)
+			0,		// NRDD (Read Data-Data) (0-3)
+			5		// NRAD (Read Addr-Data) (0-31)
+			);
+	} else {
+		/* do HW reset */
+		outb( 0,info->io_base + 8 );
+	}
+
+	info->mbre_bit = 0;
+	info->loopback_bits = 0;
+	info->usc_idle_mode = 0;
+
+	/*
+	 * Program the Bus Configuration Register (BCR)
+	 *
+	 * <15>		0	Don't use separate address
+	 * <14..6>	0	reserved
+	 * <5..4>	00	IAckmode = Default, don't care
+	 * <3>		1	Bus Request Totem Pole output
+	 * <2>		1	Use 16 Bit data bus
+	 * <1>		0	IRQ Totem Pole output
+	 * <0>		0	Don't Shift Right Addr
+	 *
+	 * 0000 0000 0000 1100 = 0x000c
+	 *
+	 * By writing to io_base + SDPIN the Wait/Ack pin is
+	 * programmed to work as a Wait pin.
+	 */
+	
+	outw( 0x000c,info->io_base + SDPIN );
+
+
+	outw( 0,info->io_base );
+	outw( 0,info->io_base + CCAR );
+
+	/* select little endian byte ordering */
+	usc_RTCmd( info, RTCmd_SelectLittleEndian );
+
+
+	/* Port Control Register (PCR)
+	 *
+	 * <15..14>	11	Port 7 is Output (~DMAEN, Bit 14 : 0 = Enabled)
+	 * <13..12>	11	Port 6 is Output (~INTEN, Bit 12 : 0 = Enabled)
+	 * <11..10> 	00	Port 5 is Input (No Connect, Don't Care)
+	 * <9..8> 	00	Port 4 is Input (No Connect, Don't Care)
+	 * <7..6>	11	Port 3 is Output (~RTS, Bit 6 : 0 = Enabled )
+	 * <5..4>	11	Port 2 is Output (~DTR, Bit 4 : 0 = Enabled )
+	 * <3..2>	01	Port 1 is Input (Dedicated RxC)
+	 * <1..0>	01	Port 0 is Input (Dedicated TxC)
+	 *
+	 *	1111 0000 1111 0101 = 0xf0f5
+	 */
+
+	usc_OutReg( info, PCR, 0xf0f5 );
+
+
+	/*
+	 * Input/Output Control Register
+	 *
+	 * <15..14>	00	CTS is active low input
+	 * <13..12>	00	DCD is active low input
+	 * <11..10>	00	TxREQ pin is input (DSR)
+	 * <9..8>	00	RxREQ pin is input (RI)
+	 * <7..6>	00	TxD is output (Transmit Data)
+	 * <5..3>	000	TxC Pin in Input (14.7456MHz Clock)
+	 * <2..0>	100	RxC is Output (drive with BRG0)
+	 *
+	 *	0000 0000 0000 0100 = 0x0004
+	 */
+
+	usc_OutReg( info, IOCR, 0x0004 );
+
+}	/* end of usc_reset() */
+
+/* usc_set_async_mode()
+ *
+ *	Program adapter for asynchronous communications.
+ *
+ * Arguments:		info		pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_set_async_mode( struct mgsl_struct *info )
+{
+	u16 RegValue;
+
+	/* disable interrupts while programming USC */
+	usc_DisableMasterIrqBit( info );
+
+	outw( 0, info->io_base ); 			/* clear Master Bus Enable (DCAR) */
+	usc_DmaCmd( info, DmaCmd_ResetAllChannels );	/* disable both DMA channels */
+
+	usc_loopback_frame( info );
+
+	/* Channel mode Register (CMR)
+	 *
+	 * <15..14>	00	Tx Sub modes, 00 = 1 Stop Bit
+	 * <13..12>	00	              00 = 16X Clock
+	 * <11..8>	0000	Transmitter mode = Asynchronous
+	 * <7..6>	00	reserved?
+	 * <5..4>	00	Rx Sub modes, 00 = 16X Clock
+	 * <3..0>	0000	Receiver mode = Asynchronous
+	 *
+	 * 0000 0000 0000 0000 = 0x0
+	 */
+
+	RegValue = 0;
+	if ( info->params.stop_bits != 1 )
+		RegValue |= BIT14;
+	usc_OutReg( info, CMR, RegValue );
+
+	
+	/* Receiver mode Register (RMR)
+	 *
+	 * <15..13>	000	encoding = None
+	 * <12..08>	00000	reserved (Sync Only)
+	 * <7..6>   	00	Even parity
+	 * <5>		0	parity disabled
+	 * <4..2>	000	Receive Char Length = 8 bits
+	 * <1..0>	00	Disable Receiver
+	 *
+	 * 0000 0000 0000 0000 = 0x0
+	 */
+
+	RegValue = 0;
+
+	if ( info->params.data_bits != 8 )
+		RegValue |= BIT4+BIT3+BIT2;
+
+	if ( info->params.parity != ASYNC_PARITY_NONE ) {
+		RegValue |= BIT5;
+		if ( info->params.parity != ASYNC_PARITY_ODD )
+			RegValue |= BIT6;
+	}
+
+	usc_OutReg( info, RMR, RegValue );
+
+
+	/* Set IRQ trigger level */
+
+	usc_RCmd( info, RCmd_SelectRicrIntLevel );
+
+	
+	/* Receive Interrupt Control Register (RICR)
+	 *
+	 * <15..8>	?		RxFIFO IRQ Request Level
+	 *
+	 * Note: For async mode the receive FIFO level must be set
+	 * to 0 to aviod the situation where the FIFO contains fewer bytes
+	 * than the trigger level and no more data is expected.
+	 *
+	 * <7>		0		Exited Hunt IA (Interrupt Arm)
+	 * <6>		0		Idle Received IA
+	 * <5>		0		Break/Abort IA
+	 * <4>		0		Rx Bound IA
+	 * <3>		0		Queued status reflects oldest byte in FIFO
+	 * <2>		0		Abort/PE IA
+	 * <1>		0		Rx Overrun IA
+	 * <0>		0		Select TC0 value for readback
+	 *
+	 * 0000 0000 0100 0000 = 0x0000 + (FIFOLEVEL in MSB)
+	 */
+	
+	usc_OutReg( info, RICR, 0x0000 );
+
+	usc_UnlatchRxstatusBits( info, RXSTATUS_ALL );
+	usc_ClearIrqPendingBits( info, RECEIVE_STATUS );
+
+	
+	/* Transmit mode Register (TMR)
+	 *
+	 * <15..13>	000	encoding = None
+	 * <12..08>	00000	reserved (Sync Only)
+	 * <7..6>	00	Transmit parity Even
+	 * <5>		0	Transmit parity Disabled
+	 * <4..2>	000	Tx Char Length = 8 bits
+	 * <1..0>	00	Disable Transmitter
+	 *
+	 * 0000 0000 0000 0000 = 0x0
+	 */
+
+	RegValue = 0;
+
+	if ( info->params.data_bits != 8 )
+		RegValue |= BIT4+BIT3+BIT2;
+
+	if ( info->params.parity != ASYNC_PARITY_NONE ) {
+		RegValue |= BIT5;
+		if ( info->params.parity != ASYNC_PARITY_ODD )
+			RegValue |= BIT6;
+	}
+
+	usc_OutReg( info, TMR, RegValue );
+
+	usc_set_txidle( info );
+
+
+	/* Set IRQ trigger level */
+
+	usc_TCmd( info, TCmd_SelectTicrIntLevel );
+
+	
+	/* Transmit Interrupt Control Register (TICR)
+	 *
+	 * <15..8>	?	Transmit FIFO IRQ Level
+	 * <7>		0	Present IA (Interrupt Arm)
+	 * <6>		1	Idle Sent IA
+	 * <5>		0	Abort Sent IA
+	 * <4>		0	EOF/EOM Sent IA
+	 * <3>		0	CRC Sent IA
+	 * <2>		0	1 = Wait for SW Trigger to Start Frame
+	 * <1>		0	Tx Underrun IA
+	 * <0>		0	TC0 constant on read back
+	 *
+	 *	0000 0000 0100 0000 = 0x0040
+	 */
+
+	usc_OutReg( info, TICR, 0x1f40 );
+
+	usc_UnlatchTxstatusBits( info, TXSTATUS_ALL );
+	usc_ClearIrqPendingBits( info, TRANSMIT_STATUS );
+
+	usc_enable_async_clock( info, info->params.data_rate );
+
+	
+	/* Channel Control/status Register (CCSR)
+	 *
+	 * <15>		X	RCC FIFO Overflow status (RO)
+	 * <14>		X	RCC FIFO Not Empty status (RO)
+	 * <13>		0	1 = Clear RCC FIFO (WO)
+	 * <12>		X	DPLL in Sync status (RO)
+	 * <11>		X	DPLL 2 Missed Clocks status (RO)
+	 * <10>		X	DPLL 1 Missed Clock status (RO)
+	 * <9..8>	00	DPLL Resync on rising and falling edges (RW)
+	 * <7>		X	SDLC Loop On status (RO)
+	 * <6>		X	SDLC Loop Send status (RO)
+	 * <5>		1	Bypass counters for TxClk and RxClk (RW)
+	 * <4..2>   	000	Last Char of SDLC frame has 8 bits (RW)
+	 * <1..0>   	00	reserved
+	 *
+	 *	0000 0000 0010 0000 = 0x0020
+	 */
+	
+	usc_OutReg( info, CCSR, 0x0020 );
+
+	usc_DisableInterrupts( info, TRANSMIT_STATUS + TRANSMIT_DATA +
+			      RECEIVE_DATA + RECEIVE_STATUS );
+
+	usc_ClearIrqPendingBits( info, TRANSMIT_STATUS + TRANSMIT_DATA +
+				RECEIVE_DATA + RECEIVE_STATUS );
+
+	usc_EnableMasterIrqBit( info );
+
+	if (info->bus_type == MGSL_BUS_TYPE_ISA) {
+		/* Enable INTEN (Port 6, Bit12) */
+		/* This connects the IRQ request signal to the ISA bus */
+		usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT13) & ~BIT12));
+	}
+
+}	/* end of usc_set_async_mode() */
+
+/* usc_loopback_frame()
+ *
+ *	Loop back a small (2 byte) dummy SDLC frame.
+ *	Interrupts and DMA are NOT used. The purpose of this is to
+ *	clear any 'stale' status info left over from running in	async mode.
+ *
+ *	The 16C32 shows the strange behaviour of marking the 1st
+ *	received SDLC frame with a CRC error even when there is no
+ *	CRC error. To get around this a small dummy from of 2 bytes
+ *	is looped back when switching from async to sync mode.
+ *
+ * Arguments:		info		pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_loopback_frame( struct mgsl_struct *info )
+{
+	int i;
+	unsigned long oldmode = info->params.mode;
+
+	info->params.mode = MGSL_MODE_HDLC;
+	
+	usc_DisableMasterIrqBit( info );
+
+	usc_set_sdlc_mode( info );
+	usc_enable_loopback( info, 1 );
+
+	/* Write 16-bit Time Constant for BRG0 */
+	usc_OutReg( info, TC0R, 0 );
+	
+	/* Channel Control Register (CCR)
+	 *
+	 * <15..14>	00	Don't use 32-bit Tx Control Blocks (TCBs)
+	 * <13>		0	Trigger Tx on SW Command Disabled
+	 * <12>		0	Flag Preamble Disabled
+	 * <11..10>	00	Preamble Length = 8-Bits
+	 * <9..8>	01	Preamble Pattern = flags
+	 * <7..6>	10	Don't use 32-bit Rx status Blocks (RSBs)
+	 * <5>		0	Trigger Rx on SW Command Disabled
+	 * <4..0>	0	reserved
+	 *
+	 *	0000 0001 0000 0000 = 0x0100
+	 */
+
+	usc_OutReg( info, CCR, 0x0100 );
+
+	/* SETUP RECEIVER */
+	usc_RTCmd( info, RTCmd_PurgeRxFifo );
+	usc_EnableReceiver(info,ENABLE_UNCONDITIONAL);
+
+	/* SETUP TRANSMITTER */
+	/* Program the Transmit Character Length Register (TCLR) */
+	/* and clear FIFO (TCC is loaded with TCLR on FIFO clear) */
+	usc_OutReg( info, TCLR, 2 );
+	usc_RTCmd( info, RTCmd_PurgeTxFifo );
+
+	/* unlatch Tx status bits, and start transmit channel. */
+	usc_UnlatchTxstatusBits(info,TXSTATUS_ALL);
+	outw(0,info->io_base + DATAREG);
+
+	/* ENABLE TRANSMITTER */
+	usc_TCmd( info, TCmd_SendFrame );
+	usc_EnableTransmitter(info,ENABLE_UNCONDITIONAL);
+							
+	/* WAIT FOR RECEIVE COMPLETE */
+	for (i=0 ; i<1000 ; i++)
+		if (usc_InReg( info, RCSR ) & (BIT8 + BIT4 + BIT3 + BIT1))
+			break;
+
+	/* clear Internal Data loopback mode */
+	usc_enable_loopback(info, 0);
+
+	usc_EnableMasterIrqBit(info);
+
+	info->params.mode = oldmode;
+
+}	/* end of usc_loopback_frame() */
+
+/* usc_set_sync_mode()	Programs the USC for SDLC communications.
+ *
+ * Arguments:		info	pointer to adapter info structure
+ * Return Value:	None
+ */
+static void usc_set_sync_mode( struct mgsl_struct *info )
+{
+	usc_loopback_frame( info );
+	usc_set_sdlc_mode( info );
+
+	if (info->bus_type == MGSL_BUS_TYPE_ISA) {
+		/* Enable INTEN (Port 6, Bit12) */
+		/* This connects the IRQ request signal to the ISA bus */
+		usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT13) & ~BIT12));
+	}
+
+	usc_enable_aux_clock(info, info->params.clock_speed);
+
+	if (info->params.loopback)
+		usc_enable_loopback(info,1);
+
+}	/* end of mgsl_set_sync_mode() */
+
+/* usc_set_txidle()	Set the HDLC idle mode for the transmitter.
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_set_txidle( struct mgsl_struct *info )
+{
+	u16 usc_idle_mode = IDLEMODE_FLAGS;
+
+	/* Map API idle mode to USC register bits */
+
+	switch( info->idle_mode ){
+	case HDLC_TXIDLE_FLAGS:			usc_idle_mode = IDLEMODE_FLAGS; break;
+	case HDLC_TXIDLE_ALT_ZEROS_ONES:	usc_idle_mode = IDLEMODE_ALT_ONE_ZERO; break;
+	case HDLC_TXIDLE_ZEROS:			usc_idle_mode = IDLEMODE_ZERO; break;
+	case HDLC_TXIDLE_ONES:			usc_idle_mode = IDLEMODE_ONE; break;
+	case HDLC_TXIDLE_ALT_MARK_SPACE:	usc_idle_mode = IDLEMODE_ALT_MARK_SPACE; break;
+	case HDLC_TXIDLE_SPACE:			usc_idle_mode = IDLEMODE_SPACE; break;
+	case HDLC_TXIDLE_MARK:			usc_idle_mode = IDLEMODE_MARK; break;
+	}
+
+	info->usc_idle_mode = usc_idle_mode;
+	//usc_OutReg(info, TCSR, usc_idle_mode);
+	info->tcsr_value &= ~IDLEMODE_MASK;	/* clear idle mode bits */
+	info->tcsr_value += usc_idle_mode;
+	usc_OutReg(info, TCSR, info->tcsr_value);
+
+	/*
+	 * if SyncLink WAN adapter is running in external sync mode, the
+	 * transmitter has been set to Monosync in order to try to mimic
+	 * a true raw outbound bit stream. Monosync still sends an open/close
+	 * sync char at the start/end of a frame. Try to match those sync
+	 * patterns to the idle mode set here
+	 */
+	if ( info->params.mode == MGSL_MODE_RAW ) {
+		unsigned char syncpat = 0;
+		switch( info->idle_mode ) {
+		case HDLC_TXIDLE_FLAGS:
+			syncpat = 0x7e;
+			break;
+		case HDLC_TXIDLE_ALT_ZEROS_ONES:
+			syncpat = 0x55;
+			break;
+		case HDLC_TXIDLE_ZEROS:
+		case HDLC_TXIDLE_SPACE:
+			syncpat = 0x00;
+			break;
+		case HDLC_TXIDLE_ONES:
+		case HDLC_TXIDLE_MARK:
+			syncpat = 0xff;
+			break;
+		case HDLC_TXIDLE_ALT_MARK_SPACE:
+			syncpat = 0xaa;
+			break;
+		}
+
+		usc_SetTransmitSyncChars(info,syncpat,syncpat);
+	}
+
+}	/* end of usc_set_txidle() */
+
+/* usc_get_serial_signals()
+ *
+ *	Query the adapter for the state of the V24 status (input) signals.
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_get_serial_signals( struct mgsl_struct *info )
+{
+	u16 status;
+
+	/* clear all serial signals except DTR and RTS */
+	info->serial_signals &= SerialSignal_DTR + SerialSignal_RTS;
+
+	/* Read the Misc Interrupt status Register (MISR) to get */
+	/* the V24 status signals. */
+
+	status = usc_InReg( info, MISR );
+
+	/* set serial signal bits to reflect MISR */
+
+	if ( status & MISCSTATUS_CTS )
+		info->serial_signals |= SerialSignal_CTS;
+
+	if ( status & MISCSTATUS_DCD )
+		info->serial_signals |= SerialSignal_DCD;
+
+	if ( status & MISCSTATUS_RI )
+		info->serial_signals |= SerialSignal_RI;
+
+	if ( status & MISCSTATUS_DSR )
+		info->serial_signals |= SerialSignal_DSR;
+
+}	/* end of usc_get_serial_signals() */
+
+/* usc_set_serial_signals()
+ *
+ *	Set the state of DTR and RTS based on contents of
+ *	serial_signals member of device extension.
+ *	
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void usc_set_serial_signals( struct mgsl_struct *info )
+{
+	u16 Control;
+	unsigned char V24Out = info->serial_signals;
+
+	/* get the current value of the Port Control Register (PCR) */
+
+	Control = usc_InReg( info, PCR );
+
+	if ( V24Out & SerialSignal_RTS )
+		Control &= ~(BIT6);
+	else
+		Control |= BIT6;
+
+	if ( V24Out & SerialSignal_DTR )
+		Control &= ~(BIT4);
+	else
+		Control |= BIT4;
+
+	usc_OutReg( info, PCR, Control );
+
+}	/* end of usc_set_serial_signals() */
+
+/* usc_enable_async_clock()
+ *
+ *	Enable the async clock at the specified frequency.
+ *
+ * Arguments:		info		pointer to device instance data
+ *			data_rate	data rate of clock in bps
+ *					0 disables the AUX clock.
+ * Return Value:	None
+ */
+static void usc_enable_async_clock( struct mgsl_struct *info, u32 data_rate )
+{
+	if ( data_rate )	{
+		/*
+		 * Clock mode Control Register (CMCR)
+		 * 
+		 * <15..14>     00      counter 1 Disabled
+		 * <13..12>     00      counter 0 Disabled
+		 * <11..10>     11      BRG1 Input is TxC Pin
+		 * <9..8>       11      BRG0 Input is TxC Pin
+		 * <7..6>       01      DPLL Input is BRG1 Output
+		 * <5..3>       100     TxCLK comes from BRG0
+		 * <2..0>       100     RxCLK comes from BRG0
+		 *
+		 * 0000 1111 0110 0100 = 0x0f64
+		 */
+		
+		usc_OutReg( info, CMCR, 0x0f64 );
+
+
+		/*
+		 * Write 16-bit Time Constant for BRG0
+		 * Time Constant = (ClkSpeed / data_rate) - 1
+		 * ClkSpeed = 921600 (ISA), 691200 (PCI)
+		 */
+
+		if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+			usc_OutReg( info, TC0R, (u16)((691200/data_rate) - 1) );
+		else
+			usc_OutReg( info, TC0R, (u16)((921600/data_rate) - 1) );
+
+		
+		/*
+		 * Hardware Configuration Register (HCR)
+		 * Clear Bit 1, BRG0 mode = Continuous
+		 * Set Bit 0 to enable BRG0.
+		 */
+
+		usc_OutReg( info, HCR,
+			    (u16)((usc_InReg( info, HCR ) & ~BIT1) | BIT0) );
+
+
+		/* Input/Output Control Reg, <2..0> = 100, Drive RxC pin with BRG0 */
+
+		usc_OutReg( info, IOCR,
+			    (u16)((usc_InReg(info, IOCR) & 0xfff8) | 0x0004) );
+	} else {
+		/* data rate == 0 so turn off BRG0 */
+		usc_OutReg( info, HCR, (u16)(usc_InReg( info, HCR ) & ~BIT0) );
+	}
+
+}	/* end of usc_enable_async_clock() */
+
+/*
+ * Buffer Structures:
+ *
+ * Normal memory access uses virtual addresses that can make discontiguous
+ * physical memory pages appear to be contiguous in the virtual address
+ * space (the processors memory mapping handles the conversions).
+ *
+ * DMA transfers require physically contiguous memory. This is because
+ * the DMA system controller and DMA bus masters deal with memory using
+ * only physical addresses.
+ *
+ * This causes a problem under Windows NT when large DMA buffers are
+ * needed. Fragmentation of the nonpaged pool prevents allocations of
+ * physically contiguous buffers larger than the PAGE_SIZE.
+ *
+ * However the 16C32 supports Bus Master Scatter/Gather DMA which
+ * allows DMA transfers to physically discontiguous buffers. Information
+ * about each data transfer buffer is contained in a memory structure
+ * called a 'buffer entry'. A list of buffer entries is maintained
+ * to track and control the use of the data transfer buffers.
+ *
+ * To support this strategy we will allocate sufficient PAGE_SIZE
+ * contiguous memory buffers to allow for the total required buffer
+ * space.
+ *
+ * The 16C32 accesses the list of buffer entries using Bus Master
+ * DMA. Control information is read from the buffer entries by the
+ * 16C32 to control data transfers. status information is written to
+ * the buffer entries by the 16C32 to indicate the status of completed
+ * transfers.
+ *
+ * The CPU writes control information to the buffer entries to control
+ * the 16C32 and reads status information from the buffer entries to
+ * determine information about received and transmitted frames.
+ *
+ * Because the CPU and 16C32 (adapter) both need simultaneous access
+ * to the buffer entries, the buffer entry memory is allocated with
+ * HalAllocateCommonBuffer(). This restricts the size of the buffer
+ * entry list to PAGE_SIZE.
+ *
+ * The actual data buffers on the other hand will only be accessed
+ * by the CPU or the adapter but not by both simultaneously. This allows
+ * Scatter/Gather packet based DMA procedures for using physically
+ * discontiguous pages.
+ */
+
+/*
+ * mgsl_reset_tx_dma_buffers()
+ *
+ * 	Set the count for all transmit buffers to 0 to indicate the
+ * 	buffer is available for use and set the current buffer to the
+ * 	first buffer. This effectively makes all buffers free and
+ * 	discards any data in buffers.
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_reset_tx_dma_buffers( struct mgsl_struct *info )
+{
+	unsigned int i;
+
+	for ( i = 0; i < info->tx_buffer_count; i++ ) {
+		*((unsigned long *)&(info->tx_buffer_list[i].count)) = 0;
+	}
+
+	info->current_tx_buffer = 0;
+	info->start_tx_dma_buffer = 0;
+	info->tx_dma_buffers_used = 0;
+
+	info->get_tx_holding_index = 0;
+	info->put_tx_holding_index = 0;
+	info->tx_holding_count = 0;
+
+}	/* end of mgsl_reset_tx_dma_buffers() */
+
+/*
+ * num_free_tx_dma_buffers()
+ *
+ * 	returns the number of free tx dma buffers available
+ *
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	number of free tx dma buffers
+ */
+static int num_free_tx_dma_buffers(struct mgsl_struct *info)
+{
+	return info->tx_buffer_count - info->tx_dma_buffers_used;
+}
+
+/*
+ * mgsl_reset_rx_dma_buffers()
+ * 
+ * 	Set the count for all receive buffers to DMABUFFERSIZE
+ * 	and set the current buffer to the first buffer. This effectively
+ * 	makes all buffers free and discards any data in buffers.
+ * 
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_reset_rx_dma_buffers( struct mgsl_struct *info )
+{
+	unsigned int i;
+
+	for ( i = 0; i < info->rx_buffer_count; i++ ) {
+		*((unsigned long *)&(info->rx_buffer_list[i].count)) = DMABUFFERSIZE;
+//		info->rx_buffer_list[i].count = DMABUFFERSIZE;
+//		info->rx_buffer_list[i].status = 0;
+	}
+
+	info->current_rx_buffer = 0;
+
+}	/* end of mgsl_reset_rx_dma_buffers() */
+
+/*
+ * mgsl_free_rx_frame_buffers()
+ * 
+ * 	Free the receive buffers used by a received SDLC
+ * 	frame such that the buffers can be reused.
+ * 
+ * Arguments:
+ * 
+ * 	info			pointer to device instance data
+ * 	StartIndex		index of 1st receive buffer of frame
+ * 	EndIndex		index of last receive buffer of frame
+ * 
+ * Return Value:	None
+ */
+static void mgsl_free_rx_frame_buffers( struct mgsl_struct *info, unsigned int StartIndex, unsigned int EndIndex )
+{
+	int Done = 0;
+	DMABUFFERENTRY *pBufEntry;
+	unsigned int Index;
+
+	/* Starting with 1st buffer entry of the frame clear the status */
+	/* field and set the count field to DMA Buffer Size. */
+
+	Index = StartIndex;
+
+	while( !Done ) {
+		pBufEntry = &(info->rx_buffer_list[Index]);
+
+		if ( Index == EndIndex ) {
+			/* This is the last buffer of the frame! */
+			Done = 1;
+		}
+
+		/* reset current buffer for reuse */
+//		pBufEntry->status = 0;
+//		pBufEntry->count = DMABUFFERSIZE;
+		*((unsigned long *)&(pBufEntry->count)) = DMABUFFERSIZE;
+
+		/* advance to next buffer entry in linked list */
+		Index++;
+		if ( Index == info->rx_buffer_count )
+			Index = 0;
+	}
+
+	/* set current buffer to next buffer after last buffer of frame */
+	info->current_rx_buffer = Index;
+
+}	/* end of free_rx_frame_buffers() */
+
+/* mgsl_get_rx_frame()
+ * 
+ * 	This function attempts to return a received SDLC frame from the
+ * 	receive DMA buffers. Only frames received without errors are returned.
+ *
+ * Arguments:	 	info	pointer to device extension
+ * Return Value:	1 if frame returned, otherwise 0
+ */
+static int mgsl_get_rx_frame(struct mgsl_struct *info)
+{
+	unsigned int StartIndex, EndIndex;	/* index of 1st and last buffers of Rx frame */
+	unsigned short status;
+	DMABUFFERENTRY *pBufEntry;
+	unsigned int framesize = 0;
+	int ReturnCode = 0;
+	unsigned long flags;
+	struct tty_struct *tty = info->tty;
+	int return_frame = 0;
+	
+	/*
+	 * current_rx_buffer points to the 1st buffer of the next available
+	 * receive frame. To find the last buffer of the frame look for
+	 * a non-zero status field in the buffer entries. (The status
+	 * field is set by the 16C32 after completing a receive frame.
+	 */
+
+	StartIndex = EndIndex = info->current_rx_buffer;
+
+	while( !info->rx_buffer_list[EndIndex].status ) {
+		/*
+		 * If the count field of the buffer entry is non-zero then
+		 * this buffer has not been used. (The 16C32 clears the count
+		 * field when it starts using the buffer.) If an unused buffer
+		 * is encountered then there are no frames available.
+		 */
+
+		if ( info->rx_buffer_list[EndIndex].count )
+			goto Cleanup;
+
+		/* advance to next buffer entry in linked list */
+		EndIndex++;
+		if ( EndIndex == info->rx_buffer_count )
+			EndIndex = 0;
+
+		/* if entire list searched then no frame available */
+		if ( EndIndex == StartIndex ) {
+			/* If this occurs then something bad happened,
+			 * all buffers have been 'used' but none mark
+			 * the end of a frame. Reset buffers and receiver.
+			 */
+
+			if ( info->rx_enabled ){
+				spin_lock_irqsave(&info->irq_spinlock,flags);
+				usc_start_receiver(info);
+				spin_unlock_irqrestore(&info->irq_spinlock,flags);
+			}
+			goto Cleanup;
+		}
+	}
+
+
+	/* check status of receive frame */
+	
+	status = info->rx_buffer_list[EndIndex].status;
+
+	if ( status & (RXSTATUS_SHORT_FRAME + RXSTATUS_OVERRUN +
+			RXSTATUS_CRC_ERROR + RXSTATUS_ABORT) ) {
+		if ( status & RXSTATUS_SHORT_FRAME )
+			info->icount.rxshort++;
+		else if ( status & RXSTATUS_ABORT )
+			info->icount.rxabort++;
+		else if ( status & RXSTATUS_OVERRUN )
+			info->icount.rxover++;
+		else {
+			info->icount.rxcrc++;
+			if ( info->params.crc_type & HDLC_CRC_RETURN_EX )
+				return_frame = 1;
+		}
+		framesize = 0;
+#ifdef CONFIG_HDLC
+		{
+			struct net_device_stats *stats = hdlc_stats(info->netdev);
+			stats->rx_errors++;
+			stats->rx_frame_errors++;
+		}
+#endif
+	} else
+		return_frame = 1;
+
+	if ( return_frame ) {
+		/* receive frame has no errors, get frame size.
+		 * The frame size is the starting value of the RCC (which was
+		 * set to 0xffff) minus the ending value of the RCC (decremented
+		 * once for each receive character) minus 2 for the 16-bit CRC.
+		 */
+
+		framesize = RCLRVALUE - info->rx_buffer_list[EndIndex].rcc;
+
+		/* adjust frame size for CRC if any */
+		if ( info->params.crc_type == HDLC_CRC_16_CCITT )
+			framesize -= 2;
+		else if ( info->params.crc_type == HDLC_CRC_32_CCITT )
+			framesize -= 4;		
+	}
+
+	if ( debug_level >= DEBUG_LEVEL_BH )
+		printk("%s(%d):mgsl_get_rx_frame(%s) status=%04X size=%d\n",
+			__FILE__,__LINE__,info->device_name,status,framesize);
+			
+	if ( debug_level >= DEBUG_LEVEL_DATA )
+		mgsl_trace_block(info,info->rx_buffer_list[StartIndex].virt_addr,
+			min_t(int, framesize, DMABUFFERSIZE),0);
+		
+	if (framesize) {
+		if ( ( (info->params.crc_type & HDLC_CRC_RETURN_EX) &&
+				((framesize+1) > info->max_frame_size) ) ||
+			(framesize > info->max_frame_size) )
+			info->icount.rxlong++;
+		else {
+			/* copy dma buffer(s) to contiguous intermediate buffer */
+			int copy_count = framesize;
+			int index = StartIndex;
+			unsigned char *ptmp = info->intermediate_rxbuffer;
+
+			if ( !(status & RXSTATUS_CRC_ERROR))
+			info->icount.rxok++;
+			
+			while(copy_count) {
+				int partial_count;
+				if ( copy_count > DMABUFFERSIZE )
+					partial_count = DMABUFFERSIZE;
+				else
+					partial_count = copy_count;
+			
+				pBufEntry = &(info->rx_buffer_list[index]);
+				memcpy( ptmp, pBufEntry->virt_addr, partial_count );
+				ptmp += partial_count;
+				copy_count -= partial_count;
+				
+				if ( ++index == info->rx_buffer_count )
+					index = 0;
+			}
+
+			if ( info->params.crc_type & HDLC_CRC_RETURN_EX ) {
+				++framesize;
+				*ptmp = (status & RXSTATUS_CRC_ERROR ?
+						RX_CRC_ERROR :
+						RX_OK);
+
+				if ( debug_level >= DEBUG_LEVEL_DATA )
+					printk("%s(%d):mgsl_get_rx_frame(%s) rx frame status=%d\n",
+						__FILE__,__LINE__,info->device_name,
+						*ptmp);
+			}
+
+#ifdef CONFIG_HDLC
+			if (info->netcount)
+				hdlcdev_rx(info,info->intermediate_rxbuffer,framesize);
+			else
+#endif
+				ldisc_receive_buf(tty, info->intermediate_rxbuffer, info->flag_buf, framesize);
+		}
+	}
+	/* Free the buffers used by this frame. */
+	mgsl_free_rx_frame_buffers( info, StartIndex, EndIndex );
+
+	ReturnCode = 1;
+
+Cleanup:
+
+	if ( info->rx_enabled && info->rx_overflow ) {
+		/* The receiver needs to restarted because of 
+		 * a receive overflow (buffer or FIFO). If the 
+		 * receive buffers are now empty, then restart receiver.
+		 */
+
+		if ( !info->rx_buffer_list[EndIndex].status &&
+			info->rx_buffer_list[EndIndex].count ) {
+			spin_lock_irqsave(&info->irq_spinlock,flags);
+			usc_start_receiver(info);
+			spin_unlock_irqrestore(&info->irq_spinlock,flags);
+		}
+	}
+
+	return ReturnCode;
+
+}	/* end of mgsl_get_rx_frame() */
+
+/* mgsl_get_raw_rx_frame()
+ *
+ *     	This function attempts to return a received frame from the
+ *	receive DMA buffers when running in external loop mode. In this mode,
+ *	we will return at most one DMABUFFERSIZE frame to the application.
+ *	The USC receiver is triggering off of DCD going active to start a new
+ *	frame, and DCD going inactive to terminate the frame (similar to
+ *	processing a closing flag character).
+ *
+ *	In this routine, we will return DMABUFFERSIZE "chunks" at a time.
+ *	If DCD goes inactive, the last Rx DMA Buffer will have a non-zero
+ * 	status field and the RCC field will indicate the length of the
+ *	entire received frame. We take this RCC field and get the modulus
+ *	of RCC and DMABUFFERSIZE to determine if number of bytes in the
+ *	last Rx DMA buffer and return that last portion of the frame.
+ *
+ * Arguments:	 	info	pointer to device extension
+ * Return Value:	1 if frame returned, otherwise 0
+ */
+static int mgsl_get_raw_rx_frame(struct mgsl_struct *info)
+{
+	unsigned int CurrentIndex, NextIndex;
+	unsigned short status;
+	DMABUFFERENTRY *pBufEntry;
+	unsigned int framesize = 0;
+	int ReturnCode = 0;
+	unsigned long flags;
+	struct tty_struct *tty = info->tty;
+
+	/*
+ 	 * current_rx_buffer points to the 1st buffer of the next available
+	 * receive frame. The status field is set by the 16C32 after
+	 * completing a receive frame. If the status field of this buffer
+	 * is zero, either the USC is still filling this buffer or this
+	 * is one of a series of buffers making up a received frame.
+	 *
+	 * If the count field of this buffer is zero, the USC is either
+	 * using this buffer or has used this buffer. Look at the count
+	 * field of the next buffer. If that next buffer's count is
+	 * non-zero, the USC is still actively using the current buffer.
+	 * Otherwise, if the next buffer's count field is zero, the
+	 * current buffer is complete and the USC is using the next
+	 * buffer.
+	 */
+	CurrentIndex = NextIndex = info->current_rx_buffer;
+	++NextIndex;
+	if ( NextIndex == info->rx_buffer_count )
+		NextIndex = 0;
+
+	if ( info->rx_buffer_list[CurrentIndex].status != 0 ||
+		(info->rx_buffer_list[CurrentIndex].count == 0 &&
+			info->rx_buffer_list[NextIndex].count == 0)) {
+		/*
+	 	 * Either the status field of this dma buffer is non-zero
+		 * (indicating the last buffer of a receive frame) or the next
+	 	 * buffer is marked as in use -- implying this buffer is complete
+		 * and an intermediate buffer for this received frame.
+	 	 */
+
+		status = info->rx_buffer_list[CurrentIndex].status;
+
+		if ( status & (RXSTATUS_SHORT_FRAME + RXSTATUS_OVERRUN +
+				RXSTATUS_CRC_ERROR + RXSTATUS_ABORT) ) {
+			if ( status & RXSTATUS_SHORT_FRAME )
+				info->icount.rxshort++;
+			else if ( status & RXSTATUS_ABORT )
+				info->icount.rxabort++;
+			else if ( status & RXSTATUS_OVERRUN )
+				info->icount.rxover++;
+			else
+				info->icount.rxcrc++;
+			framesize = 0;
+		} else {
+			/*
+			 * A receive frame is available, get frame size and status.
+			 *
+			 * The frame size is the starting value of the RCC (which was
+			 * set to 0xffff) minus the ending value of the RCC (decremented
+			 * once for each receive character) minus 2 or 4 for the 16-bit
+			 * or 32-bit CRC.
+			 *
+			 * If the status field is zero, this is an intermediate buffer.
+			 * It's size is 4K.
+			 *
+			 * If the DMA Buffer Entry's Status field is non-zero, the
+			 * receive operation completed normally (ie: DCD dropped). The
+			 * RCC field is valid and holds the received frame size.
+			 * It is possible that the RCC field will be zero on a DMA buffer
+			 * entry with a non-zero status. This can occur if the total
+			 * frame size (number of bytes between the time DCD goes active
+			 * to the time DCD goes inactive) exceeds 65535 bytes. In this
+			 * case the 16C32 has underrun on the RCC count and appears to
+			 * stop updating this counter to let us know the actual received
+			 * frame size. If this happens (non-zero status and zero RCC),
+			 * simply return the entire RxDMA Buffer
+			 */
+			if ( status ) {
+				/*
+				 * In the event that the final RxDMA Buffer is
+				 * terminated with a non-zero status and the RCC
+				 * field is zero, we interpret this as the RCC
+				 * having underflowed (received frame > 65535 bytes).
+				 *
+				 * Signal the event to the user by passing back
+				 * a status of RxStatus_CrcError returning the full
+				 * buffer and let the app figure out what data is
+				 * actually valid
+				 */
+				if ( info->rx_buffer_list[CurrentIndex].rcc )
+					framesize = RCLRVALUE - info->rx_buffer_list[CurrentIndex].rcc;
+				else
+					framesize = DMABUFFERSIZE;
+			}
+			else
+				framesize = DMABUFFERSIZE;
+		}
+
+		if ( framesize > DMABUFFERSIZE ) {
+			/*
+			 * if running in raw sync mode, ISR handler for
+			 * End Of Buffer events terminates all buffers at 4K.
+			 * If this frame size is said to be >4K, get the
+			 * actual number of bytes of the frame in this buffer.
+			 */
+			framesize = framesize % DMABUFFERSIZE;
+		}
+
+
+		if ( debug_level >= DEBUG_LEVEL_BH )
+			printk("%s(%d):mgsl_get_raw_rx_frame(%s) status=%04X size=%d\n",
+				__FILE__,__LINE__,info->device_name,status,framesize);
+
+		if ( debug_level >= DEBUG_LEVEL_DATA )
+			mgsl_trace_block(info,info->rx_buffer_list[CurrentIndex].virt_addr,
+				min_t(int, framesize, DMABUFFERSIZE),0);
+
+		if (framesize) {
+			/* copy dma buffer(s) to contiguous intermediate buffer */
+			/* NOTE: we never copy more than DMABUFFERSIZE bytes	*/
+
+			pBufEntry = &(info->rx_buffer_list[CurrentIndex]);
+			memcpy( info->intermediate_rxbuffer, pBufEntry->virt_addr, framesize);
+			info->icount.rxok++;
+
+			ldisc_receive_buf(tty, info->intermediate_rxbuffer, info->flag_buf, framesize);
+		}
+
+		/* Free the buffers used by this frame. */
+		mgsl_free_rx_frame_buffers( info, CurrentIndex, CurrentIndex );
+
+		ReturnCode = 1;
+	}
+
+
+	if ( info->rx_enabled && info->rx_overflow ) {
+		/* The receiver needs to restarted because of
+		 * a receive overflow (buffer or FIFO). If the
+		 * receive buffers are now empty, then restart receiver.
+		 */
+
+		if ( !info->rx_buffer_list[CurrentIndex].status &&
+			info->rx_buffer_list[CurrentIndex].count ) {
+			spin_lock_irqsave(&info->irq_spinlock,flags);
+			usc_start_receiver(info);
+			spin_unlock_irqrestore(&info->irq_spinlock,flags);
+		}
+	}
+
+	return ReturnCode;
+
+}	/* end of mgsl_get_raw_rx_frame() */
+
+/* mgsl_load_tx_dma_buffer()
+ * 
+ * 	Load the transmit DMA buffer with the specified data.
+ * 
+ * Arguments:
+ * 
+ * 	info		pointer to device extension
+ * 	Buffer		pointer to buffer containing frame to load
+ * 	BufferSize	size in bytes of frame in Buffer
+ * 
+ * Return Value: 	None
+ */
+static void mgsl_load_tx_dma_buffer(struct mgsl_struct *info,
+		const char *Buffer, unsigned int BufferSize)
+{
+	unsigned short Copycount;
+	unsigned int i = 0;
+	DMABUFFERENTRY *pBufEntry;
+	
+	if ( debug_level >= DEBUG_LEVEL_DATA )
+		mgsl_trace_block(info,Buffer, min_t(int, BufferSize, DMABUFFERSIZE), 1);
+
+	if (info->params.flags & HDLC_FLAG_HDLC_LOOPMODE) {
+		/* set CMR:13 to start transmit when
+		 * next GoAhead (abort) is received
+		 */
+	 	info->cmr_value |= BIT13;			  
+	}
+		
+	/* begin loading the frame in the next available tx dma
+	 * buffer, remember it's starting location for setting
+	 * up tx dma operation
+	 */
+	i = info->current_tx_buffer;
+	info->start_tx_dma_buffer = i;
+
+	/* Setup the status and RCC (Frame Size) fields of the 1st */
+	/* buffer entry in the transmit DMA buffer list. */
+
+	info->tx_buffer_list[i].status = info->cmr_value & 0xf000;
+	info->tx_buffer_list[i].rcc    = BufferSize;
+	info->tx_buffer_list[i].count  = BufferSize;
+
+	/* Copy frame data from 1st source buffer to the DMA buffers. */
+	/* The frame data may span multiple DMA buffers. */
+
+	while( BufferSize ){
+		/* Get a pointer to next DMA buffer entry. */
+		pBufEntry = &info->tx_buffer_list[i++];
+			
+		if ( i == info->tx_buffer_count )
+			i=0;
+
+		/* Calculate the number of bytes that can be copied from */
+		/* the source buffer to this DMA buffer. */
+		if ( BufferSize > DMABUFFERSIZE )
+			Copycount = DMABUFFERSIZE;
+		else
+			Copycount = BufferSize;
+
+		/* Actually copy data from source buffer to DMA buffer. */
+		/* Also set the data count for this individual DMA buffer. */
+		if ( info->bus_type == MGSL_BUS_TYPE_PCI )
+			mgsl_load_pci_memory(pBufEntry->virt_addr, Buffer,Copycount);
+		else
+			memcpy(pBufEntry->virt_addr, Buffer, Copycount);
+
+		pBufEntry->count = Copycount;
+
+		/* Advance source pointer and reduce remaining data count. */
+		Buffer += Copycount;
+		BufferSize -= Copycount;
+
+		++info->tx_dma_buffers_used;
+	}
+
+	/* remember next available tx dma buffer */
+	info->current_tx_buffer = i;
+
+}	/* end of mgsl_load_tx_dma_buffer() */
+
+/*
+ * mgsl_register_test()
+ * 
+ * 	Performs a register test of the 16C32.
+ * 	
+ * Arguments:		info	pointer to device instance data
+ * Return Value:		TRUE if test passed, otherwise FALSE
+ */
+static BOOLEAN mgsl_register_test( struct mgsl_struct *info )
+{
+	static unsigned short BitPatterns[] =
+		{ 0x0000, 0xffff, 0xaaaa, 0x5555, 0x1234, 0x6969, 0x9696, 0x0f0f };
+	static unsigned int Patterncount = sizeof(BitPatterns)/sizeof(unsigned short);
+	unsigned int i;
+	BOOLEAN rc = TRUE;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	usc_reset(info);
+
+	/* Verify the reset state of some registers. */
+
+	if ( (usc_InReg( info, SICR ) != 0) ||
+		  (usc_InReg( info, IVR  ) != 0) ||
+		  (usc_InDmaReg( info, DIVR ) != 0) ){
+		rc = FALSE;
+	}
+
+	if ( rc == TRUE ){
+		/* Write bit patterns to various registers but do it out of */
+		/* sync, then read back and verify values. */
+
+		for ( i = 0 ; i < Patterncount ; i++ ) {
+			usc_OutReg( info, TC0R, BitPatterns[i] );
+			usc_OutReg( info, TC1R, BitPatterns[(i+1)%Patterncount] );
+			usc_OutReg( info, TCLR, BitPatterns[(i+2)%Patterncount] );
+			usc_OutReg( info, RCLR, BitPatterns[(i+3)%Patterncount] );
+			usc_OutReg( info, RSR,  BitPatterns[(i+4)%Patterncount] );
+			usc_OutDmaReg( info, TBCR, BitPatterns[(i+5)%Patterncount] );
+
+			if ( (usc_InReg( info, TC0R ) != BitPatterns[i]) ||
+				  (usc_InReg( info, TC1R ) != BitPatterns[(i+1)%Patterncount]) ||
+				  (usc_InReg( info, TCLR ) != BitPatterns[(i+2)%Patterncount]) ||
+				  (usc_InReg( info, RCLR ) != BitPatterns[(i+3)%Patterncount]) ||
+				  (usc_InReg( info, RSR )  != BitPatterns[(i+4)%Patterncount]) ||
+				  (usc_InDmaReg( info, TBCR ) != BitPatterns[(i+5)%Patterncount]) ){
+				rc = FALSE;
+				break;
+			}
+		}
+	}
+
+	usc_reset(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	return rc;
+
+}	/* end of mgsl_register_test() */
+
+/* mgsl_irq_test() 	Perform interrupt test of the 16C32.
+ * 
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	TRUE if test passed, otherwise FALSE
+ */
+static BOOLEAN mgsl_irq_test( struct mgsl_struct *info )
+{
+	unsigned long EndTime;
+	unsigned long flags;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	usc_reset(info);
+
+	/*
+	 * Setup 16C32 to interrupt on TxC pin (14MHz clock) transition. 
+	 * The ISR sets irq_occurred to 1. 
+	 */
+
+	info->irq_occurred = FALSE;
+
+	/* Enable INTEN gate for ISA adapter (Port 6, Bit12) */
+	/* Enable INTEN (Port 6, Bit12) */
+	/* This connects the IRQ request signal to the ISA bus */
+	/* on the ISA adapter. This has no effect for the PCI adapter */
+	usc_OutReg( info, PCR, (unsigned short)((usc_InReg(info, PCR) | BIT13) & ~BIT12) );
+
+	usc_EnableMasterIrqBit(info);
+	usc_EnableInterrupts(info, IO_PIN);
+	usc_ClearIrqPendingBits(info, IO_PIN);
+	
+	usc_UnlatchIostatusBits(info, MISCSTATUS_TXC_LATCHED);
+	usc_EnableStatusIrqs(info, SICR_TXC_ACTIVE + SICR_TXC_INACTIVE);
+
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	EndTime=100;
+	while( EndTime-- && !info->irq_occurred ) {
+		msleep_interruptible(10);
+	}
+	
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	usc_reset(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+	if ( !info->irq_occurred ) 
+		return FALSE;
+	else
+		return TRUE;
+
+}	/* end of mgsl_irq_test() */
+
+/* mgsl_dma_test()
+ * 
+ * 	Perform a DMA test of the 16C32. A small frame is
+ * 	transmitted via DMA from a transmit buffer to a receive buffer
+ * 	using single buffer DMA mode.
+ * 	
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	TRUE if test passed, otherwise FALSE
+ */
+static BOOLEAN mgsl_dma_test( struct mgsl_struct *info )
+{
+	unsigned short FifoLevel;
+	unsigned long phys_addr;
+	unsigned int FrameSize;
+	unsigned int i;
+	char *TmpPtr;
+	BOOLEAN rc = TRUE;
+	unsigned short status=0;
+	unsigned long EndTime;
+	unsigned long flags;
+	MGSL_PARAMS tmp_params;
+
+	/* save current port options */
+	memcpy(&tmp_params,&info->params,sizeof(MGSL_PARAMS));
+	/* load default port options */
+	memcpy(&info->params,&default_params,sizeof(MGSL_PARAMS));
+	
+#define TESTFRAMESIZE 40
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	
+	/* setup 16C32 for SDLC DMA transfer mode */
+
+	usc_reset(info);
+	usc_set_sdlc_mode(info);
+	usc_enable_loopback(info,1);
+	
+	/* Reprogram the RDMR so that the 16C32 does NOT clear the count
+	 * field of the buffer entry after fetching buffer address. This
+	 * way we can detect a DMA failure for a DMA read (which should be
+	 * non-destructive to system memory) before we try and write to
+	 * memory (where a failure could corrupt system memory).
+	 */
+
+	/* Receive DMA mode Register (RDMR)
+	 * 
+	 * <15..14>	11	DMA mode = Linked List Buffer mode
+	 * <13>		1	RSBinA/L = store Rx status Block in List entry
+	 * <12>		0	1 = Clear count of List Entry after fetching
+	 * <11..10>	00	Address mode = Increment
+	 * <9>		1	Terminate Buffer on RxBound
+	 * <8>		0	Bus Width = 16bits
+	 * <7..0>		?	status Bits (write as 0s)
+	 * 
+	 * 1110 0010 0000 0000 = 0xe200
+	 */
+
+	usc_OutDmaReg( info, RDMR, 0xe200 );
+	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+
+	/* SETUP TRANSMIT AND RECEIVE DMA BUFFERS */
+
+	FrameSize = TESTFRAMESIZE;
+
+	/* setup 1st transmit buffer entry: */
+	/* with frame size and transmit control word */
+
+	info->tx_buffer_list[0].count  = FrameSize;
+	info->tx_buffer_list[0].rcc    = FrameSize;
+	info->tx_buffer_list[0].status = 0x4000;
+
+	/* build a transmit frame in 1st transmit DMA buffer */
+
+	TmpPtr = info->tx_buffer_list[0].virt_addr;
+	for (i = 0; i < FrameSize; i++ )
+		*TmpPtr++ = i;
+
+	/* setup 1st receive buffer entry: */
+	/* clear status, set max receive buffer size */
+
+	info->rx_buffer_list[0].status = 0;
+	info->rx_buffer_list[0].count = FrameSize + 4;
+
+	/* zero out the 1st receive buffer */
+
+	memset( info->rx_buffer_list[0].virt_addr, 0, FrameSize + 4 );
+
+	/* Set count field of next buffer entries to prevent */
+	/* 16C32 from using buffers after the 1st one. */
+
+	info->tx_buffer_list[1].count = 0;
+	info->rx_buffer_list[1].count = 0;
+	
+
+	/***************************/
+	/* Program 16C32 receiver. */
+	/***************************/
+	
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+
+	/* setup DMA transfers */
+	usc_RTCmd( info, RTCmd_PurgeRxFifo );
+
+	/* program 16C32 receiver with physical address of 1st DMA buffer entry */
+	phys_addr = info->rx_buffer_list[0].phys_entry;
+	usc_OutDmaReg( info, NRARL, (unsigned short)phys_addr );
+	usc_OutDmaReg( info, NRARU, (unsigned short)(phys_addr >> 16) );
+
+	/* Clear the Rx DMA status bits (read RDMR) and start channel */
+	usc_InDmaReg( info, RDMR );
+	usc_DmaCmd( info, DmaCmd_InitRxChannel );
+
+	/* Enable Receiver (RMR <1..0> = 10) */
+	usc_OutReg( info, RMR, (unsigned short)((usc_InReg(info, RMR) & 0xfffc) | 0x0002) );
+	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+
+	/*************************************************************/
+	/* WAIT FOR RECEIVER TO DMA ALL PARAMETERS FROM BUFFER ENTRY */
+	/*************************************************************/
+
+	/* Wait 100ms for interrupt. */
+	EndTime = jiffies + msecs_to_jiffies(100);
+
+	for(;;) {
+		if (time_after(jiffies, EndTime)) {
+			rc = FALSE;
+			break;
+		}
+
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		status = usc_InDmaReg( info, RDMR );
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+		if ( !(status & BIT4) && (status & BIT5) ) {
+			/* INITG (BIT 4) is inactive (no entry read in progress) AND */
+			/* BUSY  (BIT 5) is active (channel still active). */
+			/* This means the buffer entry read has completed. */
+			break;
+		}
+	}
+
+
+	/******************************/
+	/* Program 16C32 transmitter. */
+	/******************************/
+	
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+
+	/* Program the Transmit Character Length Register (TCLR) */
+	/* and clear FIFO (TCC is loaded with TCLR on FIFO clear) */
+
+	usc_OutReg( info, TCLR, (unsigned short)info->tx_buffer_list[0].count );
+	usc_RTCmd( info, RTCmd_PurgeTxFifo );
+
+	/* Program the address of the 1st DMA Buffer Entry in linked list */
+
+	phys_addr = info->tx_buffer_list[0].phys_entry;
+	usc_OutDmaReg( info, NTARL, (unsigned short)phys_addr );
+	usc_OutDmaReg( info, NTARU, (unsigned short)(phys_addr >> 16) );
+
+	/* unlatch Tx status bits, and start transmit channel. */
+
+	usc_OutReg( info, TCSR, (unsigned short)(( usc_InReg(info, TCSR) & 0x0f00) | 0xfa) );
+	usc_DmaCmd( info, DmaCmd_InitTxChannel );
+
+	/* wait for DMA controller to fill transmit FIFO */
+
+	usc_TCmd( info, TCmd_SelectTicrTxFifostatus );
+	
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+
+	/**********************************/
+	/* WAIT FOR TRANSMIT FIFO TO FILL */
+	/**********************************/
+	
+	/* Wait 100ms */
+	EndTime = jiffies + msecs_to_jiffies(100);
+
+	for(;;) {
+		if (time_after(jiffies, EndTime)) {
+			rc = FALSE;
+			break;
+		}
+
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		FifoLevel = usc_InReg(info, TICR) >> 8;
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+			
+		if ( FifoLevel < 16 )
+			break;
+		else
+			if ( FrameSize < 32 ) {
+				/* This frame is smaller than the entire transmit FIFO */
+				/* so wait for the entire frame to be loaded. */
+				if ( FifoLevel <= (32 - FrameSize) )
+					break;
+			}
+	}
+
+
+	if ( rc == TRUE )
+	{
+		/* Enable 16C32 transmitter. */
+
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		
+		/* Transmit mode Register (TMR), <1..0> = 10, Enable Transmitter */
+		usc_TCmd( info, TCmd_SendFrame );
+		usc_OutReg( info, TMR, (unsigned short)((usc_InReg(info, TMR) & 0xfffc) | 0x0002) );
+		
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+						
+		/******************************/
+		/* WAIT FOR TRANSMIT COMPLETE */
+		/******************************/
+
+		/* Wait 100ms */
+		EndTime = jiffies + msecs_to_jiffies(100);
+
+		/* While timer not expired wait for transmit complete */
+
+		spin_lock_irqsave(&info->irq_spinlock,flags);
+		status = usc_InReg( info, TCSR );
+		spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+		while ( !(status & (BIT6+BIT5+BIT4+BIT2+BIT1)) ) {
+			if (time_after(jiffies, EndTime)) {
+				rc = FALSE;
+				break;
+			}
+
+			spin_lock_irqsave(&info->irq_spinlock,flags);
+			status = usc_InReg( info, TCSR );
+			spin_unlock_irqrestore(&info->irq_spinlock,flags);
+		}
+	}
+
+
+	if ( rc == TRUE ){
+		/* CHECK FOR TRANSMIT ERRORS */
+		if ( status & (BIT5 + BIT1) ) 
+			rc = FALSE;
+	}
+
+	if ( rc == TRUE ) {
+		/* WAIT FOR RECEIVE COMPLETE */
+
+		/* Wait 100ms */
+		EndTime = jiffies + msecs_to_jiffies(100);
+
+		/* Wait for 16C32 to write receive status to buffer entry. */
+		status=info->rx_buffer_list[0].status;
+		while ( status == 0 ) {
+			if (time_after(jiffies, EndTime)) {
+				rc = FALSE;
+				break;
+			}
+			status=info->rx_buffer_list[0].status;
+		}
+	}
+
+
+	if ( rc == TRUE ) {
+		/* CHECK FOR RECEIVE ERRORS */
+		status = info->rx_buffer_list[0].status;
+
+		if ( status & (BIT8 + BIT3 + BIT1) ) {
+			/* receive error has occurred */
+			rc = FALSE;
+		} else {
+			if ( memcmp( info->tx_buffer_list[0].virt_addr ,
+				info->rx_buffer_list[0].virt_addr, FrameSize ) ){
+				rc = FALSE;
+			}
+		}
+	}
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	usc_reset( info );
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	/* restore current port options */
+	memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
+	
+	return rc;
+
+}	/* end of mgsl_dma_test() */
+
+/* mgsl_adapter_test()
+ * 
+ * 	Perform the register, IRQ, and DMA tests for the 16C32.
+ * 	
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	0 if success, otherwise -ENODEV
+ */
+static int mgsl_adapter_test( struct mgsl_struct *info )
+{
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):Testing device %s\n",
+			__FILE__,__LINE__,info->device_name );
+			
+	if ( !mgsl_register_test( info ) ) {
+		info->init_error = DiagStatus_AddressFailure;
+		printk( "%s(%d):Register test failure for device %s Addr=%04X\n",
+			__FILE__,__LINE__,info->device_name, (unsigned short)(info->io_base) );
+		return -ENODEV;
+	}
+
+	if ( !mgsl_irq_test( info ) ) {
+		info->init_error = DiagStatus_IrqFailure;
+		printk( "%s(%d):Interrupt test failure for device %s IRQ=%d\n",
+			__FILE__,__LINE__,info->device_name, (unsigned short)(info->irq_level) );
+		return -ENODEV;
+	}
+
+	if ( !mgsl_dma_test( info ) ) {
+		info->init_error = DiagStatus_DmaFailure;
+		printk( "%s(%d):DMA test failure for device %s DMA=%d\n",
+			__FILE__,__LINE__,info->device_name, (unsigned short)(info->dma_level) );
+		return -ENODEV;
+	}
+
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):device %s passed diagnostics\n",
+			__FILE__,__LINE__,info->device_name );
+			
+	return 0;
+
+}	/* end of mgsl_adapter_test() */
+
+/* mgsl_memory_test()
+ * 
+ * 	Test the shared memory on a PCI adapter.
+ * 
+ * Arguments:		info	pointer to device instance data
+ * Return Value:	TRUE if test passed, otherwise FALSE
+ */
+static BOOLEAN mgsl_memory_test( struct mgsl_struct *info )
+{
+	static unsigned long BitPatterns[] = { 0x0, 0x55555555, 0xaaaaaaaa,
+											0x66666666, 0x99999999, 0xffffffff, 0x12345678 };
+	unsigned long Patterncount = sizeof(BitPatterns)/sizeof(unsigned long);
+	unsigned long i;
+	unsigned long TestLimit = SHARED_MEM_ADDRESS_SIZE/sizeof(unsigned long);
+	unsigned long * TestAddr;
+
+	if ( info->bus_type != MGSL_BUS_TYPE_PCI )
+		return TRUE;
+
+	TestAddr = (unsigned long *)info->memory_base;
+
+	/* Test data lines with test pattern at one location. */
+
+	for ( i = 0 ; i < Patterncount ; i++ ) {
+		*TestAddr = BitPatterns[i];
+		if ( *TestAddr != BitPatterns[i] )
+			return FALSE;
+	}
+
+	/* Test address lines with incrementing pattern over */
+	/* entire address range. */
+
+	for ( i = 0 ; i < TestLimit ; i++ ) {
+		*TestAddr = i * 4;
+		TestAddr++;
+	}
+
+	TestAddr = (unsigned long *)info->memory_base;
+
+	for ( i = 0 ; i < TestLimit ; i++ ) {
+		if ( *TestAddr != i * 4 )
+			return FALSE;
+		TestAddr++;
+	}
+
+	memset( info->memory_base, 0, SHARED_MEM_ADDRESS_SIZE );
+
+	return TRUE;
+
+}	/* End Of mgsl_memory_test() */
+
+
+/* mgsl_load_pci_memory()
+ * 
+ * 	Load a large block of data into the PCI shared memory.
+ * 	Use this instead of memcpy() or memmove() to move data
+ * 	into the PCI shared memory.
+ * 
+ * Notes:
+ * 
+ * 	This function prevents the PCI9050 interface chip from hogging
+ * 	the adapter local bus, which can starve the 16C32 by preventing
+ * 	16C32 bus master cycles.
+ * 
+ * 	The PCI9050 documentation says that the 9050 will always release
+ * 	control of the local bus after completing the current read
+ * 	or write operation.
+ * 
+ * 	It appears that as long as the PCI9050 write FIFO is full, the
+ * 	PCI9050 treats all of the writes as a single burst transaction
+ * 	and will not release the bus. This causes DMA latency problems
+ * 	at high speeds when copying large data blocks to the shared
+ * 	memory.
+ * 
+ * 	This function in effect, breaks the a large shared memory write
+ * 	into multiple transations by interleaving a shared memory read
+ * 	which will flush the write FIFO and 'complete' the write
+ * 	transation. This allows any pending DMA request to gain control
+ * 	of the local bus in a timely fasion.
+ * 
+ * Arguments:
+ * 
+ * 	TargetPtr	pointer to target address in PCI shared memory
+ * 	SourcePtr	pointer to source buffer for data
+ * 	count		count in bytes of data to copy
+ *
+ * Return Value:	None
+ */
+static void mgsl_load_pci_memory( char* TargetPtr, const char* SourcePtr,
+	unsigned short count )
+{
+	/* 16 32-bit writes @ 60ns each = 960ns max latency on local bus */
+#define PCI_LOAD_INTERVAL 64
+
+	unsigned short Intervalcount = count / PCI_LOAD_INTERVAL;
+	unsigned short Index;
+	unsigned long Dummy;
+
+	for ( Index = 0 ; Index < Intervalcount ; Index++ )
+	{
+		memcpy(TargetPtr, SourcePtr, PCI_LOAD_INTERVAL);
+		Dummy = *((volatile unsigned long *)TargetPtr);
+		TargetPtr += PCI_LOAD_INTERVAL;
+		SourcePtr += PCI_LOAD_INTERVAL;
+	}
+
+	memcpy( TargetPtr, SourcePtr, count % PCI_LOAD_INTERVAL );
+
+}	/* End Of mgsl_load_pci_memory() */
+
+static void mgsl_trace_block(struct mgsl_struct *info,const char* data, int count, int xmit)
+{
+	int i;
+	int linecount;
+	if (xmit)
+		printk("%s tx data:\n",info->device_name);
+	else
+		printk("%s rx data:\n",info->device_name);
+		
+	while(count) {
+		if (count > 16)
+			linecount = 16;
+		else
+			linecount = count;
+			
+		for(i=0;i<linecount;i++)
+			printk("%02X ",(unsigned char)data[i]);
+		for(;i<17;i++)
+			printk("   ");
+		for(i=0;i<linecount;i++) {
+			if (data[i]>=040 && data[i]<=0176)
+				printk("%c",data[i]);
+			else
+				printk(".");
+		}
+		printk("\n");
+		
+		data  += linecount;
+		count -= linecount;
+	}
+}	/* end of mgsl_trace_block() */
+
+/* mgsl_tx_timeout()
+ * 
+ * 	called when HDLC frame times out
+ * 	update stats and do tx completion processing
+ * 	
+ * Arguments:	context		pointer to device instance data
+ * Return Value:	None
+ */
+static void mgsl_tx_timeout(unsigned long context)
+{
+	struct mgsl_struct *info = (struct mgsl_struct*)context;
+	unsigned long flags;
+	
+	if ( debug_level >= DEBUG_LEVEL_INFO )
+		printk( "%s(%d):mgsl_tx_timeout(%s)\n",
+			__FILE__,__LINE__,info->device_name);
+	if(info->tx_active &&
+	   (info->params.mode == MGSL_MODE_HDLC ||
+	    info->params.mode == MGSL_MODE_RAW) ) {
+		info->icount.txtimeout++;
+	}
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	info->tx_active = 0;
+	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+
+	if ( info->params.flags & HDLC_FLAG_HDLC_LOOPMODE )
+		usc_loopmode_cancel_transmit( info );
+
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+	
+#ifdef CONFIG_HDLC
+	if (info->netcount)
+		hdlcdev_tx_done(info);
+	else
+#endif
+		mgsl_bh_transmit(info);
+	
+}	/* end of mgsl_tx_timeout() */
+
+/* signal that there are no more frames to send, so that
+ * line is 'released' by echoing RxD to TxD when current
+ * transmission is complete (or immediately if no tx in progress).
+ */
+static int mgsl_loopmode_send_done( struct mgsl_struct * info )
+{
+	unsigned long flags;
+	
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	if (info->params.flags & HDLC_FLAG_HDLC_LOOPMODE) {
+		if (info->tx_active)
+			info->loopmode_send_done_requested = TRUE;
+		else
+			usc_loopmode_send_done(info);
+	}
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	return 0;
+}
+
+/* release the line by echoing RxD to TxD
+ * upon completion of a transmit frame
+ */
+static void usc_loopmode_send_done( struct mgsl_struct * info )
+{
+ 	info->loopmode_send_done_requested = FALSE;
+ 	/* clear CMR:13 to 0 to start echoing RxData to TxData */
+ 	info->cmr_value &= ~BIT13;			  
+ 	usc_OutReg(info, CMR, info->cmr_value);
+}
+
+/* abort a transmit in progress while in HDLC LoopMode
+ */
+static void usc_loopmode_cancel_transmit( struct mgsl_struct * info )
+{
+ 	/* reset tx dma channel and purge TxFifo */
+ 	usc_RTCmd( info, RTCmd_PurgeTxFifo );
+ 	usc_DmaCmd( info, DmaCmd_ResetTxChannel );
+  	usc_loopmode_send_done( info );
+}
+
+/* for HDLC/SDLC LoopMode, setting CMR:13 after the transmitter is enabled
+ * is an Insert Into Loop action. Upon receipt of a GoAhead sequence (RxAbort)
+ * we must clear CMR:13 to begin repeating TxData to RxData
+ */
+static void usc_loopmode_insert_request( struct mgsl_struct * info )
+{
+ 	info->loopmode_insert_requested = TRUE;
+ 
+ 	/* enable RxAbort irq. On next RxAbort, clear CMR:13 to
+ 	 * begin repeating TxData on RxData (complete insertion)
+	 */
+ 	usc_OutReg( info, RICR, 
+		(usc_InReg( info, RICR ) | RXSTATUS_ABORT_RECEIVED ) );
+		
+	/* set CMR:13 to insert into loop on next GoAhead (RxAbort) */
+	info->cmr_value |= BIT13;
+ 	usc_OutReg(info, CMR, info->cmr_value);
+}
+
+/* return 1 if station is inserted into the loop, otherwise 0
+ */
+static int usc_loopmode_active( struct mgsl_struct * info)
+{
+ 	return usc_InReg( info, CCSR ) & BIT7 ? 1 : 0 ;
+}
+
+#ifdef CONFIG_HDLC
+
+/**
+ * called by generic HDLC layer when protocol selected (PPP, frame relay, etc.)
+ * set encoding and frame check sequence (FCS) options
+ *
+ * dev       pointer to network device structure
+ * encoding  serial encoding setting
+ * parity    FCS setting
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_attach(struct net_device *dev, unsigned short encoding,
+			  unsigned short parity)
+{
+	struct mgsl_struct *info = dev_to_port(dev);
+	unsigned char  new_encoding;
+	unsigned short new_crctype;
+
+	/* return error if TTY interface open */
+	if (info->count)
+		return -EBUSY;
+
+	switch (encoding)
+	{
+	case ENCODING_NRZ:        new_encoding = HDLC_ENCODING_NRZ; break;
+	case ENCODING_NRZI:       new_encoding = HDLC_ENCODING_NRZI_SPACE; break;
+	case ENCODING_FM_MARK:    new_encoding = HDLC_ENCODING_BIPHASE_MARK; break;
+	case ENCODING_FM_SPACE:   new_encoding = HDLC_ENCODING_BIPHASE_SPACE; break;
+	case ENCODING_MANCHESTER: new_encoding = HDLC_ENCODING_BIPHASE_LEVEL; break;
+	default: return -EINVAL;
+	}
+
+	switch (parity)
+	{
+	case PARITY_NONE:            new_crctype = HDLC_CRC_NONE; break;
+	case PARITY_CRC16_PR1_CCITT: new_crctype = HDLC_CRC_16_CCITT; break;
+	case PARITY_CRC32_PR1_CCITT: new_crctype = HDLC_CRC_32_CCITT; break;
+	default: return -EINVAL;
+	}
+
+	info->params.encoding = new_encoding;
+	info->params.crc_type = new_crctype;;
+
+	/* if network interface up, reprogram hardware */
+	if (info->netcount)
+		mgsl_program_hw(info);
+
+	return 0;
+}
+
+/**
+ * called by generic HDLC layer to send frame
+ *
+ * skb  socket buffer containing HDLC frame
+ * dev  pointer to network device structure
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct mgsl_struct *info = dev_to_port(dev);
+	struct net_device_stats *stats = hdlc_stats(dev);
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk(KERN_INFO "%s:hdlc_xmit(%s)\n",__FILE__,dev->name);
+
+	/* stop sending until this frame completes */
+	netif_stop_queue(dev);
+
+	/* copy data to device buffers */
+	info->xmit_cnt = skb->len;
+	mgsl_load_tx_dma_buffer(info, skb->data, skb->len);
+
+	/* update network statistics */
+	stats->tx_packets++;
+	stats->tx_bytes += skb->len;
+
+	/* done with socket buffer, so free it */
+	dev_kfree_skb(skb);
+
+	/* save start time for transmit timeout detection */
+	dev->trans_start = jiffies;
+
+	/* start hardware transmitter if necessary */
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	if (!info->tx_active)
+	 	usc_start_transmitter(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	return 0;
+}
+
+/**
+ * called by network layer when interface enabled
+ * claim resources and initialize hardware
+ *
+ * dev  pointer to network device structure
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_open(struct net_device *dev)
+{
+	struct mgsl_struct *info = dev_to_port(dev);
+	int rc;
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s:hdlcdev_open(%s)\n",__FILE__,dev->name);
+
+	/* generic HDLC layer open processing */
+	if ((rc = hdlc_open(dev)))
+		return rc;
+
+	/* arbitrate between network and tty opens */
+	spin_lock_irqsave(&info->netlock, flags);
+	if (info->count != 0 || info->netcount != 0) {
+		printk(KERN_WARNING "%s: hdlc_open returning busy\n", dev->name);
+		spin_unlock_irqrestore(&info->netlock, flags);
+		return -EBUSY;
+	}
+	info->netcount=1;
+	spin_unlock_irqrestore(&info->netlock, flags);
+
+	/* claim resources and init adapter */
+	if ((rc = startup(info)) != 0) {
+		spin_lock_irqsave(&info->netlock, flags);
+		info->netcount=0;
+		spin_unlock_irqrestore(&info->netlock, flags);
+		return rc;
+	}
+
+	/* assert DTR and RTS, apply hardware settings */
+	info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+	mgsl_program_hw(info);
+
+	/* enable network layer transmit */
+	dev->trans_start = jiffies;
+	netif_start_queue(dev);
+
+	/* inform generic HDLC layer of current DCD status */
+	spin_lock_irqsave(&info->irq_spinlock, flags);
+	usc_get_serial_signals(info);
+	spin_unlock_irqrestore(&info->irq_spinlock, flags);
+	hdlc_set_carrier(info->serial_signals & SerialSignal_DCD, dev);
+
+	return 0;
+}
+
+/**
+ * called by network layer when interface is disabled
+ * shutdown hardware and release resources
+ *
+ * dev  pointer to network device structure
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_close(struct net_device *dev)
+{
+	struct mgsl_struct *info = dev_to_port(dev);
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s:hdlcdev_close(%s)\n",__FILE__,dev->name);
+
+	netif_stop_queue(dev);
+
+	/* shutdown adapter and release resources */
+	shutdown(info);
+
+	hdlc_close(dev);
+
+	spin_lock_irqsave(&info->netlock, flags);
+	info->netcount=0;
+	spin_unlock_irqrestore(&info->netlock, flags);
+
+	return 0;
+}
+
+/**
+ * called by network layer to process IOCTL call to network device
+ *
+ * dev  pointer to network device structure
+ * ifr  pointer to network interface request structure
+ * cmd  IOCTL command code
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
+{
+	const size_t size = sizeof(sync_serial_settings);
+	sync_serial_settings new_line;
+	sync_serial_settings __user *line = ifr->ifr_settings.ifs_ifsu.sync;
+	struct mgsl_struct *info = dev_to_port(dev);
+	unsigned int flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("%s:hdlcdev_ioctl(%s)\n",__FILE__,dev->name);
+
+	/* return error if TTY interface open */
+	if (info->count)
+		return -EBUSY;
+
+	if (cmd != SIOCWANDEV)
+		return hdlc_ioctl(dev, ifr, cmd);
+
+	switch(ifr->ifr_settings.type) {
+	case IF_GET_IFACE: /* return current sync_serial_settings */
+
+		ifr->ifr_settings.type = IF_IFACE_SYNC_SERIAL;
+		if (ifr->ifr_settings.size < size) {
+			ifr->ifr_settings.size = size; /* data size wanted */
+			return -ENOBUFS;
+		}
+
+		flags = info->params.flags & (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
+
+		switch (flags){
+		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN): new_line.clock_type = CLOCK_EXT; break;
+		case (HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_INT; break;
+		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG):    new_line.clock_type = CLOCK_TXINT; break;
+		case (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN): new_line.clock_type = CLOCK_TXFROMRX; break;
+		default: new_line.clock_type = CLOCK_DEFAULT;
+		}
+
+		new_line.clock_rate = info->params.clock_speed;
+		new_line.loopback   = info->params.loopback ? 1:0;
+
+		if (copy_to_user(line, &new_line, size))
+			return -EFAULT;
+		return 0;
+
+	case IF_IFACE_SYNC_SERIAL: /* set sync_serial_settings */
+
+		if(!capable(CAP_NET_ADMIN))
+			return -EPERM;
+		if (copy_from_user(&new_line, line, size))
+			return -EFAULT;
+
+		switch (new_line.clock_type)
+		{
+		case CLOCK_EXT:      flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_TXCPIN; break;
+		case CLOCK_TXFROMRX: flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_RXCPIN; break;
+		case CLOCK_INT:      flags = HDLC_FLAG_RXC_BRG    | HDLC_FLAG_TXC_BRG;    break;
+		case CLOCK_TXINT:    flags = HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_TXC_BRG;    break;
+		case CLOCK_DEFAULT:  flags = info->params.flags &
+					     (HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+					      HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+					      HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+					      HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN); break;
+		default: return -EINVAL;
+		}
+
+		if (new_line.loopback != 0 && new_line.loopback != 1)
+			return -EINVAL;
+
+		info->params.flags &= ~(HDLC_FLAG_RXC_RXCPIN | HDLC_FLAG_RXC_DPLL |
+					HDLC_FLAG_RXC_BRG    | HDLC_FLAG_RXC_TXCPIN |
+					HDLC_FLAG_TXC_TXCPIN | HDLC_FLAG_TXC_DPLL |
+					HDLC_FLAG_TXC_BRG    | HDLC_FLAG_TXC_RXCPIN);
+		info->params.flags |= flags;
+
+		info->params.loopback = new_line.loopback;
+
+		if (flags & (HDLC_FLAG_RXC_BRG | HDLC_FLAG_TXC_BRG))
+			info->params.clock_speed = new_line.clock_rate;
+		else
+			info->params.clock_speed = 0;
+
+		/* if network interface up, reprogram hardware */
+		if (info->netcount)
+			mgsl_program_hw(info);
+		return 0;
+
+	default:
+		return hdlc_ioctl(dev, ifr, cmd);
+	}
+}
+
+/**
+ * called by network layer when transmit timeout is detected
+ *
+ * dev  pointer to network device structure
+ */
+static void hdlcdev_tx_timeout(struct net_device *dev)
+{
+	struct mgsl_struct *info = dev_to_port(dev);
+	struct net_device_stats *stats = hdlc_stats(dev);
+	unsigned long flags;
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("hdlcdev_tx_timeout(%s)\n",dev->name);
+
+	stats->tx_errors++;
+	stats->tx_aborted_errors++;
+
+	spin_lock_irqsave(&info->irq_spinlock,flags);
+	usc_stop_transmitter(info);
+	spin_unlock_irqrestore(&info->irq_spinlock,flags);
+
+	netif_wake_queue(dev);
+}
+
+/**
+ * called by device driver when transmit completes
+ * reenable network layer transmit if stopped
+ *
+ * info  pointer to device instance information
+ */
+static void hdlcdev_tx_done(struct mgsl_struct *info)
+{
+	if (netif_queue_stopped(info->netdev))
+		netif_wake_queue(info->netdev);
+}
+
+/**
+ * called by device driver when frame received
+ * pass frame to network layer
+ *
+ * info  pointer to device instance information
+ * buf   pointer to buffer contianing frame data
+ * size  count of data bytes in buf
+ */
+static void hdlcdev_rx(struct mgsl_struct *info, char *buf, int size)
+{
+	struct sk_buff *skb = dev_alloc_skb(size);
+	struct net_device *dev = info->netdev;
+	struct net_device_stats *stats = hdlc_stats(dev);
+
+	if (debug_level >= DEBUG_LEVEL_INFO)
+		printk("hdlcdev_rx(%s)\n",dev->name);
+
+	if (skb == NULL) {
+		printk(KERN_NOTICE "%s: can't alloc skb, dropping packet\n", dev->name);
+		stats->rx_dropped++;
+		return;
+	}
+
+	memcpy(skb_put(skb, size),buf,size);
+
+	skb->protocol = hdlc_type_trans(skb, info->netdev);
+
+	stats->rx_packets++;
+	stats->rx_bytes += size;
+
+	netif_rx(skb);
+
+	info->netdev->last_rx = jiffies;
+}
+
+/**
+ * called by device driver when adding device instance
+ * do generic HDLC initialization
+ *
+ * info  pointer to device instance information
+ *
+ * returns 0 if success, otherwise error code
+ */
+static int hdlcdev_init(struct mgsl_struct *info)
+{
+	int rc;
+	struct net_device *dev;
+	hdlc_device *hdlc;
+
+	/* allocate and initialize network and HDLC layer objects */
+
+	if (!(dev = alloc_hdlcdev(info))) {
+		printk(KERN_ERR "%s:hdlc device allocation failure\n",__FILE__);
+		return -ENOMEM;
+	}
+
+	/* for network layer reporting purposes only */
+	dev->base_addr = info->io_base;
+	dev->irq       = info->irq_level;
+	dev->dma       = info->dma_level;
+
+	/* network layer callbacks and settings */
+	dev->do_ioctl       = hdlcdev_ioctl;
+	dev->open           = hdlcdev_open;
+	dev->stop           = hdlcdev_close;
+	dev->tx_timeout     = hdlcdev_tx_timeout;
+	dev->watchdog_timeo = 10*HZ;
+	dev->tx_queue_len   = 50;
+
+	/* generic HDLC layer callbacks and settings */
+	hdlc         = dev_to_hdlc(dev);
+	hdlc->attach = hdlcdev_attach;
+	hdlc->xmit   = hdlcdev_xmit;
+
+	/* register objects with HDLC layer */
+	if ((rc = register_hdlc_device(dev))) {
+		printk(KERN_WARNING "%s:unable to register hdlc device\n",__FILE__);
+		free_netdev(dev);
+		return rc;
+	}
+
+	info->netdev = dev;
+	return 0;
+}
+
+/**
+ * called by device driver when removing device instance
+ * do generic HDLC cleanup
+ *
+ * info  pointer to device instance information
+ */
+static void hdlcdev_exit(struct mgsl_struct *info)
+{
+	unregister_hdlc_device(info->netdev);
+	free_netdev(info->netdev);
+	info->netdev = NULL;
+}
+
+#endif /* CONFIG_HDLC */
+
+
+static int __devinit synclink_init_one (struct pci_dev *dev,
+					const struct pci_device_id *ent)
+{
+	struct mgsl_struct *info;
+
+	if (pci_enable_device(dev)) {
+		printk("error enabling pci device %p\n", dev);
+		return -EIO;
+	}
+
+	if (!(info = mgsl_allocate_device())) {
+		printk("can't allocate device instance data.\n");
+		return -EIO;
+	}
+
+        /* Copy user configuration info to device instance data */
+		
+	info->io_base = pci_resource_start(dev, 2);
+	info->irq_level = dev->irq;
+	info->phys_memory_base = pci_resource_start(dev, 3);
+				
+        /* Because veremap only works on page boundaries we must map
+	 * a larger area than is actually implemented for the LCR
+	 * memory range. We map a full page starting at the page boundary.
+	 */
+	info->phys_lcr_base = pci_resource_start(dev, 0);
+	info->lcr_offset    = info->phys_lcr_base & (PAGE_SIZE-1);
+	info->phys_lcr_base &= ~(PAGE_SIZE-1);
+				
+	info->bus_type = MGSL_BUS_TYPE_PCI;
+	info->io_addr_size = 8;
+	info->irq_flags = SA_SHIRQ;
+
+	if (dev->device == 0x0210) {
+		/* Version 1 PCI9030 based universal PCI adapter */
+		info->misc_ctrl_value = 0x007c4080;
+		info->hw_version = 1;
+	} else {
+		/* Version 0 PCI9050 based 5V PCI adapter
+		 * A PCI9050 bug prevents reading LCR registers if 
+		 * LCR base address bit 7 is set. Maintain shadow
+		 * value so we can write to LCR misc control reg.
+		 */
+		info->misc_ctrl_value = 0x087e4546;
+		info->hw_version = 0;
+	}
+				
+	mgsl_add_device(info);
+
+	return 0;
+}
+
+static void __devexit synclink_remove_one (struct pci_dev *dev)
+{
+}
+