diff options
Diffstat (limited to 'drivers/tty/serial/imx.c')
| -rw-r--r-- | drivers/tty/serial/imx.c | 1380 |
1 files changed, 1380 insertions, 0 deletions
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c new file mode 100644 index 000000000000..dfcf4b1878aa --- /dev/null +++ b/drivers/tty/serial/imx.c @@ -0,0 +1,1380 @@ +/* + * linux/drivers/serial/imx.c + * + * Driver for Motorola IMX serial ports + * + * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o. + * + * Author: Sascha Hauer <sascha@saschahauer.de> + * Copyright (C) 2004 Pengutronix + * + * Copyright (C) 2009 emlix GmbH + * Author: Fabian Godehardt (added IrDA support for iMX) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + * [29-Mar-2005] Mike Lee + * Added hardware handshake + */ + +#if defined(CONFIG_SERIAL_IMX_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) +#define SUPPORT_SYSRQ +#endif + +#include <linux/module.h> +#include <linux/ioport.h> +#include <linux/init.h> +#include <linux/console.h> +#include <linux/sysrq.h> +#include <linux/platform_device.h> +#include <linux/tty.h> +#include <linux/tty_flip.h> +#include <linux/serial_core.h> +#include <linux/serial.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/rational.h> +#include <linux/slab.h> + +#include <asm/io.h> +#include <asm/irq.h> +#include <mach/hardware.h> +#include <mach/imx-uart.h> + +/* Register definitions */ +#define URXD0 0x0 /* Receiver Register */ +#define URTX0 0x40 /* Transmitter Register */ +#define UCR1 0x80 /* Control Register 1 */ +#define UCR2 0x84 /* Control Register 2 */ +#define UCR3 0x88 /* Control Register 3 */ +#define UCR4 0x8c /* Control Register 4 */ +#define UFCR 0x90 /* FIFO Control Register */ +#define USR1 0x94 /* Status Register 1 */ +#define USR2 0x98 /* Status Register 2 */ +#define UESC 0x9c /* Escape Character Register */ +#define UTIM 0xa0 /* Escape Timer Register */ +#define UBIR 0xa4 /* BRM Incremental Register */ +#define UBMR 0xa8 /* BRM Modulator Register */ +#define UBRC 0xac /* Baud Rate Count Register */ +#define MX2_ONEMS 0xb0 /* One Millisecond register */ +#define UTS (cpu_is_mx1() ? 0xd0 : 0xb4) /* UART Test Register */ + +/* UART Control Register Bit Fields.*/ +#define URXD_CHARRDY (1<<15) +#define URXD_ERR (1<<14) +#define URXD_OVRRUN (1<<13) +#define URXD_FRMERR (1<<12) +#define URXD_BRK (1<<11) +#define URXD_PRERR (1<<10) +#define UCR1_ADEN (1<<15) /* Auto dectect interrupt */ +#define UCR1_ADBR (1<<14) /* Auto detect baud rate */ +#define UCR1_TRDYEN (1<<13) /* Transmitter ready interrupt enable */ +#define UCR1_IDEN (1<<12) /* Idle condition interrupt */ +#define UCR1_RRDYEN (1<<9) /* Recv ready interrupt enable */ +#define UCR1_RDMAEN (1<<8) /* Recv ready DMA enable */ +#define UCR1_IREN (1<<7) /* Infrared interface enable */ +#define UCR1_TXMPTYEN (1<<6) /* Transimitter empty interrupt enable */ +#define UCR1_RTSDEN (1<<5) /* RTS delta interrupt enable */ +#define UCR1_SNDBRK (1<<4) /* Send break */ +#define UCR1_TDMAEN (1<<3) /* Transmitter ready DMA enable */ +#define MX1_UCR1_UARTCLKEN (1<<2) /* UART clock enabled, mx1 only */ +#define UCR1_DOZE (1<<1) /* Doze */ +#define UCR1_UARTEN (1<<0) /* UART enabled */ +#define UCR2_ESCI (1<<15) /* Escape seq interrupt enable */ +#define UCR2_IRTS (1<<14) /* Ignore RTS pin */ +#define UCR2_CTSC (1<<13) /* CTS pin control */ +#define UCR2_CTS (1<<12) /* Clear to send */ +#define UCR2_ESCEN (1<<11) /* Escape enable */ +#define UCR2_PREN (1<<8) /* Parity enable */ +#define UCR2_PROE (1<<7) /* Parity odd/even */ +#define UCR2_STPB (1<<6) /* Stop */ +#define UCR2_WS (1<<5) /* Word size */ +#define UCR2_RTSEN (1<<4) /* Request to send interrupt enable */ +#define UCR2_TXEN (1<<2) /* Transmitter enabled */ +#define UCR2_RXEN (1<<1) /* Receiver enabled */ +#define UCR2_SRST (1<<0) /* SW reset */ +#define UCR3_DTREN (1<<13) /* DTR interrupt enable */ +#define UCR3_PARERREN (1<<12) /* Parity enable */ +#define UCR3_FRAERREN (1<<11) /* Frame error interrupt enable */ +#define UCR3_DSR (1<<10) /* Data set ready */ +#define UCR3_DCD (1<<9) /* Data carrier detect */ +#define UCR3_RI (1<<8) /* Ring indicator */ +#define UCR3_TIMEOUTEN (1<<7) /* Timeout interrupt enable */ +#define UCR3_RXDSEN (1<<6) /* Receive status interrupt enable */ +#define UCR3_AIRINTEN (1<<5) /* Async IR wake interrupt enable */ +#define UCR3_AWAKEN (1<<4) /* Async wake interrupt enable */ +#define MX1_UCR3_REF25 (1<<3) /* Ref freq 25 MHz, only on mx1 */ +#define MX1_UCR3_REF30 (1<<2) /* Ref Freq 30 MHz, only on mx1 */ +#define MX2_UCR3_RXDMUXSEL (1<<2) /* RXD Muxed Input Select, on mx2/mx3 */ +#define UCR3_INVT (1<<1) /* Inverted Infrared transmission */ +#define UCR3_BPEN (1<<0) /* Preset registers enable */ +#define UCR4_CTSTL_SHF 10 /* CTS trigger level shift */ +#define UCR4_CTSTL_MASK 0x3F /* CTS trigger is 6 bits wide */ +#define UCR4_INVR (1<<9) /* Inverted infrared reception */ +#define UCR4_ENIRI (1<<8) /* Serial infrared interrupt enable */ +#define UCR4_WKEN (1<<7) /* Wake interrupt enable */ +#define UCR4_REF16 (1<<6) /* Ref freq 16 MHz */ +#define UCR4_IRSC (1<<5) /* IR special case */ +#define UCR4_TCEN (1<<3) /* Transmit complete interrupt enable */ +#define UCR4_BKEN (1<<2) /* Break condition interrupt enable */ +#define UCR4_OREN (1<<1) /* Receiver overrun interrupt enable */ +#define UCR4_DREN (1<<0) /* Recv data ready interrupt enable */ +#define UFCR_RXTL_SHF 0 /* Receiver trigger level shift */ +#define UFCR_RFDIV (7<<7) /* Reference freq divider mask */ +#define UFCR_RFDIV_REG(x) (((x) < 7 ? 6 - (x) : 6) << 7) +#define UFCR_TXTL_SHF 10 /* Transmitter trigger level shift */ +#define USR1_PARITYERR (1<<15) /* Parity error interrupt flag */ +#define USR1_RTSS (1<<14) /* RTS pin status */ +#define USR1_TRDY (1<<13) /* Transmitter ready interrupt/dma flag */ +#define USR1_RTSD (1<<12) /* RTS delta */ +#define USR1_ESCF (1<<11) /* Escape seq interrupt flag */ +#define USR1_FRAMERR (1<<10) /* Frame error interrupt flag */ +#define USR1_RRDY (1<<9) /* Receiver ready interrupt/dma flag */ +#define USR1_TIMEOUT (1<<7) /* Receive timeout interrupt status */ +#define USR1_RXDS (1<<6) /* Receiver idle interrupt flag */ +#define USR1_AIRINT (1<<5) /* Async IR wake interrupt flag */ +#define USR1_AWAKE (1<<4) /* Aysnc wake interrupt flag */ +#define USR2_ADET (1<<15) /* Auto baud rate detect complete */ +#define USR2_TXFE (1<<14) /* Transmit buffer FIFO empty */ +#define USR2_DTRF (1<<13) /* DTR edge interrupt flag */ +#define USR2_IDLE (1<<12) /* Idle condition */ +#define USR2_IRINT (1<<8) /* Serial infrared interrupt flag */ +#define USR2_WAKE (1<<7) /* Wake */ +#define USR2_RTSF (1<<4) /* RTS edge interrupt flag */ +#define USR2_TXDC (1<<3) /* Transmitter complete */ +#define USR2_BRCD (1<<2) /* Break condition */ +#define USR2_ORE (1<<1) /* Overrun error */ +#define USR2_RDR (1<<0) /* Recv data ready */ +#define UTS_FRCPERR (1<<13) /* Force parity error */ +#define UTS_LOOP (1<<12) /* Loop tx and rx */ +#define UTS_TXEMPTY (1<<6) /* TxFIFO empty */ +#define UTS_RXEMPTY (1<<5) /* RxFIFO empty */ +#define UTS_TXFULL (1<<4) /* TxFIFO full */ +#define UTS_RXFULL (1<<3) /* RxFIFO full */ +#define UTS_SOFTRST (1<<0) /* Software reset */ + +/* We've been assigned a range on the "Low-density serial ports" major */ +#define SERIAL_IMX_MAJOR 207 +#define MINOR_START 16 +#define DEV_NAME "ttymxc" +#define MAX_INTERNAL_IRQ MXC_INTERNAL_IRQS + +/* + * This determines how often we check the modem status signals + * for any change. They generally aren't connected to an IRQ + * so we have to poll them. We also check immediately before + * filling the TX fifo incase CTS has been dropped. + */ +#define MCTRL_TIMEOUT (250*HZ/1000) + +#define DRIVER_NAME "IMX-uart" + +#define UART_NR 8 + +struct imx_port { + struct uart_port port; + struct timer_list timer; + unsigned int old_status; + int txirq,rxirq,rtsirq; + unsigned int have_rtscts:1; + unsigned int use_irda:1; + unsigned int irda_inv_rx:1; + unsigned int irda_inv_tx:1; + unsigned short trcv_delay; /* transceiver delay */ + struct clk *clk; +}; + +#ifdef CONFIG_IRDA +#define USE_IRDA(sport) ((sport)->use_irda) +#else +#define USE_IRDA(sport) (0) +#endif + +/* + * Handle any change of modem status signal since we were last called. + */ +static void imx_mctrl_check(struct imx_port *sport) +{ + unsigned int status, changed; + + status = sport->port.ops->get_mctrl(&sport->port); + changed = status ^ sport->old_status; + + if (changed == 0) + return; + + sport->old_status = status; + + if (changed & TIOCM_RI) + sport->port.icount.rng++; + if (changed & TIOCM_DSR) + sport->port.icount.dsr++; + if (changed & TIOCM_CAR) + uart_handle_dcd_change(&sport->port, status & TIOCM_CAR); + if (changed & TIOCM_CTS) + uart_handle_cts_change(&sport->port, status & TIOCM_CTS); + + wake_up_interruptible(&sport->port.state->port.delta_msr_wait); +} + +/* + * This is our per-port timeout handler, for checking the + * modem status signals. + */ +static void imx_timeout(unsigned long data) +{ + struct imx_port *sport = (struct imx_port *)data; + unsigned long flags; + + if (sport->port.state) { + spin_lock_irqsave(&sport->port.lock, flags); + imx_mctrl_check(sport); + spin_unlock_irqrestore(&sport->port.lock, flags); + + mod_timer(&sport->timer, jiffies + MCTRL_TIMEOUT); + } +} + +/* + * interrupts disabled on entry + */ +static void imx_stop_tx(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned long temp; + + if (USE_IRDA(sport)) { + /* half duplex - wait for end of transmission */ + int n = 256; + while ((--n > 0) && + !(readl(sport->port.membase + USR2) & USR2_TXDC)) { + udelay(5); + barrier(); + } + /* + * irda transceiver - wait a bit more to avoid + * cutoff, hardware dependent + */ + udelay(sport->trcv_delay); + + /* + * half duplex - reactivate receive mode, + * flush receive pipe echo crap + */ + if (readl(sport->port.membase + USR2) & USR2_TXDC) { + temp = readl(sport->port.membase + UCR1); + temp &= ~(UCR1_TXMPTYEN | UCR1_TRDYEN); + writel(temp, sport->port.membase + UCR1); + + temp = readl(sport->port.membase + UCR4); + temp &= ~(UCR4_TCEN); + writel(temp, sport->port.membase + UCR4); + + while (readl(sport->port.membase + URXD0) & + URXD_CHARRDY) + barrier(); + + temp = readl(sport->port.membase + UCR1); + temp |= UCR1_RRDYEN; + writel(temp, sport->port.membase + UCR1); + + temp = readl(sport->port.membase + UCR4); + temp |= UCR4_DREN; + writel(temp, sport->port.membase + UCR4); + } + return; + } + + temp = readl(sport->port.membase + UCR1); + writel(temp & ~UCR1_TXMPTYEN, sport->port.membase + UCR1); +} + +/* + * interrupts disabled on entry + */ +static void imx_stop_rx(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned long temp; + + temp = readl(sport->port.membase + UCR2); + writel(temp &~ UCR2_RXEN, sport->port.membase + UCR2); +} + +/* + * Set the modem control timer to fire immediately. + */ +static void imx_enable_ms(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + + mod_timer(&sport->timer, jiffies); +} + +static inline void imx_transmit_buffer(struct imx_port *sport) +{ + struct circ_buf *xmit = &sport->port.state->xmit; + + while (!uart_circ_empty(xmit) && + !(readl(sport->port.membase + UTS) & UTS_TXFULL)) { + /* send xmit->buf[xmit->tail] + * out the port here */ + writel(xmit->buf[xmit->tail], sport->port.membase + URTX0); + xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); + sport->port.icount.tx++; + } + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(&sport->port); + + if (uart_circ_empty(xmit)) + imx_stop_tx(&sport->port); +} + +/* + * interrupts disabled on entry + */ +static void imx_start_tx(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned long temp; + + if (USE_IRDA(sport)) { + /* half duplex in IrDA mode; have to disable receive mode */ + temp = readl(sport->port.membase + UCR4); + temp &= ~(UCR4_DREN); + writel(temp, sport->port.membase + UCR4); + + temp = readl(sport->port.membase + UCR1); + temp &= ~(UCR1_RRDYEN); + writel(temp, sport->port.membase + UCR1); + } + + temp = readl(sport->port.membase + UCR1); + writel(temp | UCR1_TXMPTYEN, sport->port.membase + UCR1); + + if (USE_IRDA(sport)) { + temp = readl(sport->port.membase + UCR1); + temp |= UCR1_TRDYEN; + writel(temp, sport->port.membase + UCR1); + + temp = readl(sport->port.membase + UCR4); + temp |= UCR4_TCEN; + writel(temp, sport->port.membase + UCR4); + } + + if (readl(sport->port.membase + UTS) & UTS_TXEMPTY) + imx_transmit_buffer(sport); +} + +static irqreturn_t imx_rtsint(int irq, void *dev_id) +{ + struct imx_port *sport = dev_id; + unsigned int val = readl(sport->port.membase + USR1) & USR1_RTSS; + unsigned long flags; + + spin_lock_irqsave(&sport->port.lock, flags); + + writel(USR1_RTSD, sport->port.membase + USR1); + uart_handle_cts_change(&sport->port, !!val); + wake_up_interruptible(&sport->port.state->port.delta_msr_wait); + + spin_unlock_irqrestore(&sport->port.lock, flags); + return IRQ_HANDLED; +} + +static irqreturn_t imx_txint(int irq, void *dev_id) +{ + struct imx_port *sport = dev_id; + struct circ_buf *xmit = &sport->port.state->xmit; + unsigned long flags; + + spin_lock_irqsave(&sport->port.lock,flags); + if (sport->port.x_char) + { + /* Send next char */ + writel(sport->port.x_char, sport->port.membase + URTX0); + goto out; + } + + if (uart_circ_empty(xmit) || uart_tx_stopped(&sport->port)) { + imx_stop_tx(&sport->port); + goto out; + } + + imx_transmit_buffer(sport); + + if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) + uart_write_wakeup(&sport->port); + +out: + spin_unlock_irqrestore(&sport->port.lock,flags); + return IRQ_HANDLED; +} + +static irqreturn_t imx_rxint(int irq, void *dev_id) +{ + struct imx_port *sport = dev_id; + unsigned int rx,flg,ignored = 0; + struct tty_struct *tty = sport->port.state->port.tty; + unsigned long flags, temp; + + spin_lock_irqsave(&sport->port.lock,flags); + + while (readl(sport->port.membase + USR2) & USR2_RDR) { + flg = TTY_NORMAL; + sport->port.icount.rx++; + + rx = readl(sport->port.membase + URXD0); + + temp = readl(sport->port.membase + USR2); + if (temp & USR2_BRCD) { + writel(USR2_BRCD, sport->port.membase + USR2); + if (uart_handle_break(&sport->port)) + continue; + } + + if (uart_handle_sysrq_char(&sport->port, (unsigned char)rx)) + continue; + + if (rx & (URXD_PRERR | URXD_OVRRUN | URXD_FRMERR) ) { + if (rx & URXD_PRERR) + sport->port.icount.parity++; + else if (rx & URXD_FRMERR) + sport->port.icount.frame++; + if (rx & URXD_OVRRUN) + sport->port.icount.overrun++; + + if (rx & sport->port.ignore_status_mask) { + if (++ignored > 100) + goto out; + continue; + } + + rx &= sport->port.read_status_mask; + + if (rx & URXD_PRERR) + flg = TTY_PARITY; + else if (rx & URXD_FRMERR) + flg = TTY_FRAME; + if (rx & URXD_OVRRUN) + flg = TTY_OVERRUN; + +#ifdef SUPPORT_SYSRQ + sport->port.sysrq = 0; +#endif + } + + tty_insert_flip_char(tty, rx, flg); + } + +out: + spin_unlock_irqrestore(&sport->port.lock,flags); + tty_flip_buffer_push(tty); + return IRQ_HANDLED; +} + +static irqreturn_t imx_int(int irq, void *dev_id) +{ + struct imx_port *sport = dev_id; + unsigned int sts; + + sts = readl(sport->port.membase + USR1); + + if (sts & USR1_RRDY) + imx_rxint(irq, dev_id); + + if (sts & USR1_TRDY && + readl(sport->port.membase + UCR1) & UCR1_TXMPTYEN) + imx_txint(irq, dev_id); + + if (sts & USR1_RTSD) + imx_rtsint(irq, dev_id); + + return IRQ_HANDLED; +} + +/* + * Return TIOCSER_TEMT when transmitter is not busy. + */ +static unsigned int imx_tx_empty(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + + return (readl(sport->port.membase + USR2) & USR2_TXDC) ? TIOCSER_TEMT : 0; +} + +/* + * We have a modem side uart, so the meanings of RTS and CTS are inverted. + */ +static unsigned int imx_get_mctrl(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned int tmp = TIOCM_DSR | TIOCM_CAR; + + if (readl(sport->port.membase + USR1) & USR1_RTSS) + tmp |= TIOCM_CTS; + + if (readl(sport->port.membase + UCR2) & UCR2_CTS) + tmp |= TIOCM_RTS; + + return tmp; +} + +static void imx_set_mctrl(struct uart_port *port, unsigned int mctrl) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned long temp; + + temp = readl(sport->port.membase + UCR2) & ~UCR2_CTS; + + if (mctrl & TIOCM_RTS) + temp |= UCR2_CTS; + + writel(temp, sport->port.membase + UCR2); +} + +/* + * Interrupts always disabled. + */ +static void imx_break_ctl(struct uart_port *port, int break_state) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned long flags, temp; + + spin_lock_irqsave(&sport->port.lock, flags); + + temp = readl(sport->port.membase + UCR1) & ~UCR1_SNDBRK; + + if ( break_state != 0 ) + temp |= UCR1_SNDBRK; + + writel(temp, sport->port.membase + UCR1); + + spin_unlock_irqrestore(&sport->port.lock, flags); +} + +#define TXTL 2 /* reset default */ +#define RXTL 1 /* reset default */ + +static int imx_setup_ufcr(struct imx_port *sport, unsigned int mode) +{ + unsigned int val; + unsigned int ufcr_rfdiv; + + /* set receiver / transmitter trigger level. + * RFDIV is set such way to satisfy requested uartclk value + */ + val = TXTL << 10 | RXTL; + ufcr_rfdiv = (clk_get_rate(sport->clk) + sport->port.uartclk / 2) + / sport->port.uartclk; + + if(!ufcr_rfdiv) + ufcr_rfdiv = 1; + + val |= UFCR_RFDIV_REG(ufcr_rfdiv); + + writel(val, sport->port.membase + UFCR); + + return 0; +} + +/* half the RX buffer size */ +#define CTSTL 16 + +static int imx_startup(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + int retval; + unsigned long flags, temp; + + imx_setup_ufcr(sport, 0); + + /* disable the DREN bit (Data Ready interrupt enable) before + * requesting IRQs + */ + temp = readl(sport->port.membase + UCR4); + + if (USE_IRDA(sport)) + temp |= UCR4_IRSC; + + /* set the trigger level for CTS */ + temp &= ~(UCR4_CTSTL_MASK<< UCR4_CTSTL_SHF); + temp |= CTSTL<< UCR4_CTSTL_SHF; + + writel(temp & ~UCR4_DREN, sport->port.membase + UCR4); + + if (USE_IRDA(sport)) { + /* reset fifo's and state machines */ + int i = 100; + temp = readl(sport->port.membase + UCR2); + temp &= ~UCR2_SRST; + writel(temp, sport->port.membase + UCR2); + while (!(readl(sport->port.membase + UCR2) & UCR2_SRST) && + (--i > 0)) { + udelay(1); + } + } + + /* + * Allocate the IRQ(s) i.MX1 has three interrupts whereas later + * chips only have one interrupt. + */ + if (sport->txirq > 0) { + retval = request_irq(sport->rxirq, imx_rxint, 0, + DRIVER_NAME, sport); + if (retval) + goto error_out1; + + retval = request_irq(sport->txirq, imx_txint, 0, + DRIVER_NAME, sport); + if (retval) + goto error_out2; + + /* do not use RTS IRQ on IrDA */ + if (!USE_IRDA(sport)) { + retval = request_irq(sport->rtsirq, imx_rtsint, + (sport->rtsirq < MAX_INTERNAL_IRQ) ? 0 : + IRQF_TRIGGER_FALLING | + IRQF_TRIGGER_RISING, + DRIVER_NAME, sport); + if (retval) + goto error_out3; + } + } else { + retval = request_irq(sport->port.irq, imx_int, 0, + DRIVER_NAME, sport); + if (retval) { + free_irq(sport->port.irq, sport); + goto error_out1; + } + } + + /* + * Finally, clear and enable interrupts + */ + writel(USR1_RTSD, sport->port.membase + USR1); + + temp = readl(sport->port.membase + UCR1); + temp |= UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN; + + if (USE_IRDA(sport)) { + temp |= UCR1_IREN; + temp &= ~(UCR1_RTSDEN); + } + + writel(temp, sport->port.membase + UCR1); + + temp = readl(sport->port.membase + UCR2); + temp |= (UCR2_RXEN | UCR2_TXEN); + writel(temp, sport->port.membase + UCR2); + + if (USE_IRDA(sport)) { + /* clear RX-FIFO */ + int i = 64; + while ((--i > 0) && + (readl(sport->port.membase + URXD0) & URXD_CHARRDY)) { + barrier(); + } + } + + if (!cpu_is_mx1()) { + temp = readl(sport->port.membase + UCR3); + temp |= MX2_UCR3_RXDMUXSEL; + writel(temp, sport->port.membase + UCR3); + } + + if (USE_IRDA(sport)) { + temp = readl(sport->port.membase + UCR4); + if (sport->irda_inv_rx) + temp |= UCR4_INVR; + else + temp &= ~(UCR4_INVR); + writel(temp | UCR4_DREN, sport->port.membase + UCR4); + + temp = readl(sport->port.membase + UCR3); + if (sport->irda_inv_tx) + temp |= UCR3_INVT; + else + temp &= ~(UCR3_INVT); + writel(temp, sport->port.membase + UCR3); + } + + /* + * Enable modem status interrupts + */ + spin_lock_irqsave(&sport->port.lock,flags); + imx_enable_ms(&sport->port); + spin_unlock_irqrestore(&sport->port.lock,flags); + + if (USE_IRDA(sport)) { + struct imxuart_platform_data *pdata; + pdata = sport->port.dev->platform_data; + sport->irda_inv_rx = pdata->irda_inv_rx; + sport->irda_inv_tx = pdata->irda_inv_tx; + sport->trcv_delay = pdata->transceiver_delay; + if (pdata->irda_enable) + pdata->irda_enable(1); + } + + return 0; + +error_out3: + if (sport->txirq) + free_irq(sport->txirq, sport); +error_out2: + if (sport->rxirq) + free_irq(sport->rxirq, sport); +error_out1: + return retval; +} + +static void imx_shutdown(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned long temp; + + temp = readl(sport->port.membase + UCR2); + temp &= ~(UCR2_TXEN); + writel(temp, sport->port.membase + UCR2); + + if (USE_IRDA(sport)) { + struct imxuart_platform_data *pdata; + pdata = sport->port.dev->platform_data; + if (pdata->irda_enable) + pdata->irda_enable(0); + } + + /* + * Stop our timer. + */ + del_timer_sync(&sport->timer); + + /* + * Free the interrupts + */ + if (sport->txirq > 0) { + if (!USE_IRDA(sport)) + free_irq(sport->rtsirq, sport); + free_irq(sport->txirq, sport); + free_irq(sport->rxirq, sport); + } else + free_irq(sport->port.irq, sport); + + /* + * Disable all interrupts, port and break condition. + */ + + temp = readl(sport->port.membase + UCR1); + temp &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN | UCR1_UARTEN); + if (USE_IRDA(sport)) + temp &= ~(UCR1_IREN); + + writel(temp, sport->port.membase + UCR1); +} + +static void +imx_set_termios(struct uart_port *port, struct ktermios *termios, + struct ktermios *old) +{ + struct imx_port *sport = (struct imx_port *)port; + unsigned long flags; + unsigned int ucr2, old_ucr1, old_txrxen, baud, quot; + unsigned int old_csize = old ? old->c_cflag & CSIZE : CS8; + unsigned int div, ufcr; + unsigned long num, denom; + uint64_t tdiv64; + + /* + * If we don't support modem control lines, don't allow + * these to be set. + */ + if (0) { + termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR); + termios->c_cflag |= CLOCAL; + } + + /* + * We only support CS7 and CS8. + */ + while ((termios->c_cflag & CSIZE) != CS7 && + (termios->c_cflag & CSIZE) != CS8) { + termios->c_cflag &= ~CSIZE; + termios->c_cflag |= old_csize; + old_csize = CS8; + } + + if ((termios->c_cflag & CSIZE) == CS8) + ucr2 = UCR2_WS | UCR2_SRST | UCR2_IRTS; + else + ucr2 = UCR2_SRST | UCR2_IRTS; + + if (termios->c_cflag & CRTSCTS) { + if( sport->have_rtscts ) { + ucr2 &= ~UCR2_IRTS; + ucr2 |= UCR2_CTSC; + } else { + termios->c_cflag &= ~CRTSCTS; + } + } + + if (termios->c_cflag & CSTOPB) + ucr2 |= UCR2_STPB; + if (termios->c_cflag & PARENB) { + ucr2 |= UCR2_PREN; + if (termios->c_cflag & PARODD) + ucr2 |= UCR2_PROE; + } + + /* + * Ask the core to calculate the divisor for us. + */ + baud = uart_get_baud_rate(port, termios, old, 50, port->uartclk / 16); + quot = uart_get_divisor(port, baud); + + spin_lock_irqsave(&sport->port.lock, flags); + + sport->port.read_status_mask = 0; + if (termios->c_iflag & INPCK) + sport->port.read_status_mask |= (URXD_FRMERR | URXD_PRERR); + if (termios->c_iflag & (BRKINT | PARMRK)) + sport->port.read_status_mask |= URXD_BRK; + + /* + * Characters to ignore + */ + sport->port.ignore_status_mask = 0; + if (termios->c_iflag & IGNPAR) + sport->port.ignore_status_mask |= URXD_PRERR; + if (termios->c_iflag & IGNBRK) { + sport->port.ignore_status_mask |= URXD_BRK; + /* + * If we're ignoring parity and break indicators, + * ignore overruns too (for real raw support). + */ + if (termios->c_iflag & IGNPAR) + sport->port.ignore_status_mask |= URXD_OVRRUN; + } + + del_timer_sync(&sport->timer); + + /* + * Update the per-port timeout. + */ + uart_update_timeout(port, termios->c_cflag, baud); + + /* + * disable interrupts and drain transmitter + */ + old_ucr1 = readl(sport->port.membase + UCR1); + writel(old_ucr1 & ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN), + sport->port.membase + UCR1); + + while ( !(readl(sport->port.membase + USR2) & USR2_TXDC)) + barrier(); + + /* then, disable everything */ + old_txrxen = readl(sport->port.membase + UCR2); + writel(old_txrxen & ~( UCR2_TXEN | UCR2_RXEN), + sport->port.membase + UCR2); + old_txrxen &= (UCR2_TXEN | UCR2_RXEN); + + if (USE_IRDA(sport)) { + /* + * use maximum available submodule frequency to + * avoid missing short pulses due to low sampling rate + */ + div = 1; + } else { + div = sport->port.uartclk / (baud * 16); + if (div > 7) + div = 7; + if (!div) + div = 1; + } + + rational_best_approximation(16 * div * baud, sport->port.uartclk, + 1 << 16, 1 << 16, &num, &denom); + + tdiv64 = sport->port.uartclk; + tdiv64 *= num; + do_div(tdiv64, denom * 16 * div); + tty_termios_encode_baud_rate(termios, + (speed_t)tdiv64, (speed_t)tdiv64); + + num -= 1; + denom -= 1; + + ufcr = readl(sport->port.membase + UFCR); + ufcr = (ufcr & (~UFCR_RFDIV)) | UFCR_RFDIV_REG(div); + writel(ufcr, sport->port.membase + UFCR); + + writel(num, sport->port.membase + UBIR); + writel(denom, sport->port.membase + UBMR); + + if (!cpu_is_mx1()) + writel(sport->port.uartclk / div / 1000, + sport->port.membase + MX2_ONEMS); + + writel(old_ucr1, sport->port.membase + UCR1); + + /* set the parity, stop bits and data size */ + writel(ucr2 | old_txrxen, sport->port.membase + UCR2); + + if (UART_ENABLE_MS(&sport->port, termios->c_cflag)) + imx_enable_ms(&sport->port); + + spin_unlock_irqrestore(&sport->port.lock, flags); +} + +static const char *imx_type(struct uart_port *port) +{ + struct imx_port *sport = (struct imx_port *)port; + + return sport->port.type == PORT_IMX ? "IMX" : NULL; +} + +/* + * Release the memory region(s) being used by 'port'. + */ +static void imx_release_port(struct uart_port *port) +{ + struct platform_device *pdev = to_platform_device(port->dev); + struct resource *mmres; + + mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); + release_mem_region(mmres->start, mmres->end - mmres->start + 1); +} + +/* + * Request the memory region(s) being used by 'port'. + */ +static int imx_request_port(struct uart_port *port) +{ + struct platform_device *pdev = to_platform_device(port->dev); + struct resource *mmres; + void *ret; + + mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!mmres) + return -ENODEV; + + ret = request_mem_region(mmres->start, mmres->end - mmres->start + 1, + "imx-uart"); + + return ret ? 0 : -EBUSY; +} + +/* + * Configure/autoconfigure the port. + */ +static void imx_config_port(struct uart_port *port, int flags) +{ + struct imx_port *sport = (struct imx_port *)port; + + if (flags & UART_CONFIG_TYPE && + imx_request_port(&sport->port) == 0) + sport->port.type = PORT_IMX; +} + +/* + * Verify the new serial_struct (for TIOCSSERIAL). + * The only change we allow are to the flags and type, and + * even then only between PORT_IMX and PORT_UNKNOWN + */ +static int +imx_verify_port(struct uart_port *port, struct serial_struct *ser) +{ + struct imx_port *sport = (struct imx_port *)port; + int ret = 0; + + if (ser->type != PORT_UNKNOWN && ser->type != PORT_IMX) + ret = -EINVAL; + if (sport->port.irq != ser->irq) + ret = -EINVAL; + if (ser->io_type != UPIO_MEM) + ret = -EINVAL; + if (sport->port.uartclk / 16 != ser->baud_base) + ret = -EINVAL; + if ((void *)sport->port.mapbase != ser->iomem_base) + ret = -EINVAL; + if (sport->port.iobase != ser->port) + ret = -EINVAL; + if (ser->hub6 != 0) + ret = -EINVAL; + return ret; +} + +static struct uart_ops imx_pops = { + .tx_empty = imx_tx_empty, + .set_mctrl = imx_set_mctrl, + .get_mctrl = imx_get_mctrl, + .stop_tx = imx_stop_tx, + .start_tx = imx_start_tx, + .stop_rx = imx_stop_rx, + .enable_ms = imx_enable_ms, + .break_ctl = imx_break_ctl, + .startup = imx_startup, + .shutdown = imx_shutdown, + .set_termios = imx_set_termios, + .type = imx_type, + .release_port = imx_release_port, + .request_port = imx_request_port, + .config_port = imx_config_port, + .verify_port = imx_verify_port, +}; + +static struct imx_port *imx_ports[UART_NR]; + +#ifdef CONFIG_SERIAL_IMX_CONSOLE +static void imx_console_putchar(struct uart_port *port, int ch) +{ + struct imx_port *sport = (struct imx_port *)port; + + while (readl(sport->port.membase + UTS) & UTS_TXFULL) + barrier(); + + writel(ch, sport->port.membase + URTX0); +} + +/* + * Interrupts are disabled on entering + */ +static void +imx_console_write(struct console *co, const char *s, unsigned int count) +{ + struct imx_port *sport = imx_ports[co->index]; + unsigned int old_ucr1, old_ucr2, ucr1; + + /* + * First, save UCR1/2 and then disable interrupts + */ + ucr1 = old_ucr1 = readl(sport->port.membase + UCR1); + old_ucr2 = readl(sport->port.membase + UCR2); + + if (cpu_is_mx1()) + ucr1 |= MX1_UCR1_UARTCLKEN; + ucr1 |= UCR1_UARTEN; + ucr1 &= ~(UCR1_TXMPTYEN | UCR1_RRDYEN | UCR1_RTSDEN); + + writel(ucr1, sport->port.membase + UCR1); + + writel(old_ucr2 | UCR2_TXEN, sport->port.membase + UCR2); + + uart_console_write(&sport->port, s, count, imx_console_putchar); + + /* + * Finally, wait for transmitter to become empty + * and restore UCR1/2 + */ + while (!(readl(sport->port.membase + USR2) & USR2_TXDC)); + + writel(old_ucr1, sport->port.membase + UCR1); + writel(old_ucr2, sport->port.membase + UCR2); +} + +/* + * If the port was already initialised (eg, by a boot loader), + * try to determine the current setup. + */ +static void __init +imx_console_get_options(struct imx_port *sport, int *baud, + int *parity, int *bits) +{ + + if (readl(sport->port.membase + UCR1) & UCR1_UARTEN) { + /* ok, the port was enabled */ + unsigned int ucr2, ubir,ubmr, uartclk; + unsigned int baud_raw; + unsigned int ucfr_rfdiv; + + ucr2 = readl(sport->port.membase + UCR2); + + *parity = 'n'; + if (ucr2 & UCR2_PREN) { + if (ucr2 & UCR2_PROE) + *parity = 'o'; + else + *parity = 'e'; + } + + if (ucr2 & UCR2_WS) + *bits = 8; + else + *bits = 7; + + ubir = readl(sport->port.membase + UBIR) & 0xffff; + ubmr = readl(sport->port.membase + UBMR) & 0xffff; + + ucfr_rfdiv = (readl(sport->port.membase + UFCR) & UFCR_RFDIV) >> 7; + if (ucfr_rfdiv == 6) + ucfr_rfdiv = 7; + else + ucfr_rfdiv = 6 - ucfr_rfdiv; + + uartclk = clk_get_rate(sport->clk); + uartclk /= ucfr_rfdiv; + + { /* + * The next code provides exact computation of + * baud_raw = round(((uartclk/16) * (ubir + 1)) / (ubmr + 1)) + * without need of float support or long long division, + * which would be required to prevent 32bit arithmetic overflow + */ + unsigned int mul = ubir + 1; + unsigned int div = 16 * (ubmr + 1); + unsigned int rem = uartclk % div; + + baud_raw = (uartclk / div) * mul; + baud_raw += (rem * mul + div / 2) / div; + *baud = (baud_raw + 50) / 100 * 100; + } + + if(*baud != baud_raw) + printk(KERN_INFO "Serial: Console IMX rounded baud rate from %d to %d\n", + baud_raw, *baud); + } +} + +static int __init +imx_console_setup(struct console *co, char *options) +{ + struct imx_port *sport; + int baud = 9600; + int bits = 8; + int parity = 'n'; + int flow = 'n'; + + /* + * Check whether an invalid uart number has been specified, and + * if so, search for the first available port that does have + * console support. + */ + if (co->index == -1 || co->index >= ARRAY_SIZE(imx_ports)) + co->index = 0; + sport = imx_ports[co->index]; + if(sport == NULL) + return -ENODEV; + + if (options) + uart_parse_options(options, &baud, &parity, &bits, &flow); + else + imx_console_get_options(sport, &baud, &parity, &bits); + + imx_setup_ufcr(sport, 0); + + return uart_set_options(&sport->port, co, baud, parity, bits, flow); +} + +static struct uart_driver imx_reg; +static struct console imx_console = { + .name = DEV_NAME, + .write = imx_console_write, + .device = uart_console_device, + .setup = imx_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, + .data = &imx_reg, +}; + +#define IMX_CONSOLE &imx_console +#else +#define IMX_CONSOLE NULL +#endif + +static struct uart_driver imx_reg = { + .owner = THIS_MODULE, + .driver_name = DRIVER_NAME, + .dev_name = DEV_NAME, + .major = SERIAL_IMX_MAJOR, + .minor = MINOR_START, + .nr = ARRAY_SIZE(imx_ports), + .cons = IMX_CONSOLE, +}; + +static int serial_imx_suspend(struct platform_device *dev, pm_message_t state) +{ + struct imx_port *sport = platform_get_drvdata(dev); + + if (sport) + uart_suspend_port(&imx_reg, &sport->port); + + return 0; +} + +static int serial_imx_resume(struct platform_device *dev) +{ + struct imx_port *sport = platform_get_drvdata(dev); + + if (sport) + uart_resume_port(&imx_reg, &sport->port); + + return 0; +} + +static int serial_imx_probe(struct platform_device *pdev) +{ + struct imx_port *sport; + struct imxuart_platform_data *pdata; + void __iomem *base; + int ret = 0; + struct resource *res; + + sport = kzalloc(sizeof(*sport), GFP_KERNEL); + if (!sport) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + ret = -ENODEV; + goto free; + } + + base = ioremap(res->start, PAGE_SIZE); + if (!base) { + ret = -ENOMEM; + goto free; + } + + sport->port.dev = &pdev->dev; + sport->port.mapbase = res->start; + sport->port.membase = base; + sport->port.type = PORT_IMX, + sport->port.iotype = UPIO_MEM; + sport->port.irq = platform_get_irq(pdev, 0); + sport->rxirq = platform_get_irq(pdev, 0); + sport->txirq = platform_get_irq(pdev, 1); + sport->rtsirq = platform_get_irq(pdev, 2); + sport->port.fifosize = 32; + sport->port.ops = &imx_pops; + sport->port.flags = UPF_BOOT_AUTOCONF; + sport->port.line = pdev->id; + init_timer(&sport->timer); + sport->timer.function = imx_timeout; + sport->timer.data = (unsigned long)sport; + + sport->clk = clk_get(&pdev->dev, "uart"); + if (IS_ERR(sport->clk)) { + ret = PTR_ERR(sport->clk); + goto unmap; + } + clk_enable(sport->clk); + + sport->port.uartclk = clk_get_rate(sport->clk); + + imx_ports[pdev->id] = sport; + + pdata = pdev->dev.platform_data; + if (pdata && (pdata->flags & IMXUART_HAVE_RTSCTS)) + sport->have_rtscts = 1; + +#ifdef CONFIG_IRDA + if (pdata && (pdata->flags & IMXUART_IRDA)) + sport->use_irda = 1; +#endif + + if (pdata && pdata->init) { + ret = pdata->init(pdev); + if (ret) + goto clkput; + } + + ret = uart_add_one_port(&imx_reg, &sport->port); + if (ret) + goto deinit; + platform_set_drvdata(pdev, &sport->port); + + return 0; +deinit: + if (pdata && pdata->exit) + pdata->exit(pdev); +clkput: + clk_put(sport->clk); + clk_disable(sport->clk); +unmap: + iounmap(sport->port.membase); +free: + kfree(sport); + + return ret; +} + +static int serial_imx_remove(struct platform_device *pdev) +{ + struct imxuart_platform_data *pdata; + struct imx_port *sport = platform_get_drvdata(pdev); + + pdata = pdev->dev.platform_data; + + platform_set_drvdata(pdev, NULL); + + if (sport) { + uart_remove_one_port(&imx_reg, &sport->port); + clk_put(sport->clk); + } + + clk_disable(sport->clk); + + if (pdata && pdata->exit) + pdata->exit(pdev); + + iounmap(sport->port.membase); + kfree(sport); + + return 0; +} + +static struct platform_driver serial_imx_driver = { + .probe = serial_imx_probe, + .remove = serial_imx_remove, + + .suspend = serial_imx_suspend, + .resume = serial_imx_resume, + .driver = { + .name = "imx-uart", + .owner = THIS_MODULE, + }, +}; + +static int __init imx_serial_init(void) +{ + int ret; + + printk(KERN_INFO "Serial: IMX driver\n"); + + ret = uart_register_driver(&imx_reg); + if (ret) + return ret; + + ret = platform_driver_register(&serial_imx_driver); + if (ret != 0) + uart_unregister_driver(&imx_reg); + + return 0; +} + +static void __exit imx_serial_exit(void) +{ + platform_driver_unregister(&serial_imx_driver); + uart_unregister_driver(&imx_reg); +} + +module_init(imx_serial_init); +module_exit(imx_serial_exit); + +MODULE_AUTHOR("Sascha Hauer"); +MODULE_DESCRIPTION("IMX generic serial port driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:imx-uart"); |
