Merge branch 'linus' into core/softlockup

Conflicts:

	kernel/softlockup.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1317 insertions, 0 deletions

diff --git a/drivers/serial/samsung.c b/drivers/serial/samsung.c
new file mode 100644
index 000000000000..4a3ecaa629e6
--- /dev/null
+++ b/drivers/serial/samsung.c
@@ -0,0 +1,1317 @@
+/* linux/drivers/serial/samsuing.c
+ *
+ * Driver core for Samsung SoC onboard UARTs.
+ *
+ * Ben Dooks, Copyright (c) 2003-2005,2008 Simtec Electronics
+ *	http://armlinux.simtec.co.uk/
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+/* Hote on 2410 error handling
+ *
+ * The s3c2410 manual has a love/hate affair with the contents of the
+ * UERSTAT register in the UART blocks, and keeps marking some of the
+ * error bits as reserved. Having checked with the s3c2410x01,
+ * it copes with BREAKs properly, so I am happy to ignore the RESERVED
+ * feature from the latter versions of the manual.
+ *
+ * If it becomes aparrent that latter versions of the 2410 remove these
+ * bits, then action will have to be taken to differentiate the versions
+ * and change the policy on BREAK
+ *
+ * BJD, 04-Nov-2004
+*/
+
+#if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
+#define SUPPORT_SYSRQ
+#endif
+
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/init.h>
+#include <linux/sysrq.h>
+#include <linux/console.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial_core.h>
+#include <linux/serial.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+
+#include <asm/irq.h>
+
+#include <asm/hardware.h>
+
+#include <asm/plat-s3c/regs-serial.h>
+#include <asm/arch/regs-gpio.h>
+
+#include "samsung.h"
+
+/* UART name and device definitions */
+
+#define S3C24XX_SERIAL_NAME	"ttySAC"
+#define S3C24XX_SERIAL_MAJOR	204
+#define S3C24XX_SERIAL_MINOR	64
+
+/* we can support 3 uarts, but not always use them */
+
+#ifdef CONFIG_CPU_S3C2400
+#define NR_PORTS (2)
+#else
+#define NR_PORTS (3)
+#endif
+
+/* port irq numbers */
+
+#define TX_IRQ(port) ((port)->irq + 1)
+#define RX_IRQ(port) ((port)->irq)
+
+/* macros to change one thing to another */
+
+#define tx_enabled(port) ((port)->unused[0])
+#define rx_enabled(port) ((port)->unused[1])
+
+/* flag to ignore all characters comming in */
+#define RXSTAT_DUMMY_READ (0x10000000)
+
+static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
+{
+	return container_of(port, struct s3c24xx_uart_port, port);
+}
+
+/* translate a port to the device name */
+
+static inline const char *s3c24xx_serial_portname(struct uart_port *port)
+{
+	return to_platform_device(port->dev)->name;
+}
+
+static int s3c24xx_serial_txempty_nofifo(struct uart_port *port)
+{
+	return (rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE);
+}
+
+static void s3c24xx_serial_rx_enable(struct uart_port *port)
+{
+	unsigned long flags;
+	unsigned int ucon, ufcon;
+	int count = 10000;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	while (--count && !s3c24xx_serial_txempty_nofifo(port))
+		udelay(100);
+
+	ufcon = rd_regl(port, S3C2410_UFCON);
+	ufcon |= S3C2410_UFCON_RESETRX;
+	wr_regl(port, S3C2410_UFCON, ufcon);
+
+	ucon = rd_regl(port, S3C2410_UCON);
+	ucon |= S3C2410_UCON_RXIRQMODE;
+	wr_regl(port, S3C2410_UCON, ucon);
+
+	rx_enabled(port) = 1;
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void s3c24xx_serial_rx_disable(struct uart_port *port)
+{
+	unsigned long flags;
+	unsigned int ucon;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	ucon = rd_regl(port, S3C2410_UCON);
+	ucon &= ~S3C2410_UCON_RXIRQMODE;
+	wr_regl(port, S3C2410_UCON, ucon);
+
+	rx_enabled(port) = 0;
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void s3c24xx_serial_stop_tx(struct uart_port *port)
+{
+	if (tx_enabled(port)) {
+		disable_irq(TX_IRQ(port));
+		tx_enabled(port) = 0;
+		if (port->flags & UPF_CONS_FLOW)
+			s3c24xx_serial_rx_enable(port);
+	}
+}
+
+static void s3c24xx_serial_start_tx(struct uart_port *port)
+{
+	if (!tx_enabled(port)) {
+		if (port->flags & UPF_CONS_FLOW)
+			s3c24xx_serial_rx_disable(port);
+
+		enable_irq(TX_IRQ(port));
+		tx_enabled(port) = 1;
+	}
+}
+
+
+static void s3c24xx_serial_stop_rx(struct uart_port *port)
+{
+	if (rx_enabled(port)) {
+		dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
+		disable_irq(RX_IRQ(port));
+		rx_enabled(port) = 0;
+	}
+}
+
+static void s3c24xx_serial_enable_ms(struct uart_port *port)
+{
+}
+
+static inline struct s3c24xx_uart_info *s3c24xx_port_to_info(struct uart_port *port)
+{
+	return to_ourport(port)->info;
+}
+
+static inline struct s3c2410_uartcfg *s3c24xx_port_to_cfg(struct uart_port *port)
+{
+	if (port->dev == NULL)
+		return NULL;
+
+	return (struct s3c2410_uartcfg *)port->dev->platform_data;
+}
+
+static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
+				     unsigned long ufstat)
+{
+	struct s3c24xx_uart_info *info = ourport->info;
+
+	if (ufstat & info->rx_fifofull)
+		return info->fifosize;
+
+	return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
+}
+
+
+/* ? - where has parity gone?? */
+#define S3C2410_UERSTAT_PARITY (0x1000)
+
+static irqreturn_t
+s3c24xx_serial_rx_chars(int irq, void *dev_id)
+{
+	struct s3c24xx_uart_port *ourport = dev_id;
+	struct uart_port *port = &ourport->port;
+	struct tty_struct *tty = port->info->tty;
+	unsigned int ufcon, ch, flag, ufstat, uerstat;
+	int max_count = 64;
+
+	while (max_count-- > 0) {
+		ufcon = rd_regl(port, S3C2410_UFCON);
+		ufstat = rd_regl(port, S3C2410_UFSTAT);
+
+		if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
+			break;
+
+		uerstat = rd_regl(port, S3C2410_UERSTAT);
+		ch = rd_regb(port, S3C2410_URXH);
+
+		if (port->flags & UPF_CONS_FLOW) {
+			int txe = s3c24xx_serial_txempty_nofifo(port);
+
+			if (rx_enabled(port)) {
+				if (!txe) {
+					rx_enabled(port) = 0;
+					continue;
+				}
+			} else {
+				if (txe) {
+					ufcon |= S3C2410_UFCON_RESETRX;
+					wr_regl(port, S3C2410_UFCON, ufcon);
+					rx_enabled(port) = 1;
+					goto out;
+				}
+				continue;
+			}
+		}
+
+		/* insert the character into the buffer */
+
+		flag = TTY_NORMAL;
+		port->icount.rx++;
+
+		if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
+			dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
+			    ch, uerstat);
+
+			/* check for break */
+			if (uerstat & S3C2410_UERSTAT_BREAK) {
+				dbg("break!\n");
+				port->icount.brk++;
+				if (uart_handle_break(port))
+				    goto ignore_char;
+			}
+
+			if (uerstat & S3C2410_UERSTAT_FRAME)
+				port->icount.frame++;
+			if (uerstat & S3C2410_UERSTAT_OVERRUN)
+				port->icount.overrun++;
+
+			uerstat &= port->read_status_mask;
+
+			if (uerstat & S3C2410_UERSTAT_BREAK)
+				flag = TTY_BREAK;
+			else if (uerstat & S3C2410_UERSTAT_PARITY)
+				flag = TTY_PARITY;
+			else if (uerstat & (S3C2410_UERSTAT_FRAME |
+					    S3C2410_UERSTAT_OVERRUN))
+				flag = TTY_FRAME;
+		}
+
+		if (uart_handle_sysrq_char(port, ch))
+			goto ignore_char;
+
+		uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
+				 ch, flag);
+
+ ignore_char:
+		continue;
+	}
+	tty_flip_buffer_push(tty);
+
+ out:
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
+{
+	struct s3c24xx_uart_port *ourport = id;
+	struct uart_port *port = &ourport->port;
+	struct circ_buf *xmit = &port->info->xmit;
+	int count = 256;
+
+	if (port->x_char) {
+		wr_regb(port, S3C2410_UTXH, port->x_char);
+		port->icount.tx++;
+		port->x_char = 0;
+		goto out;
+	}
+
+	/* if there isnt anything more to transmit, or the uart is now
+	 * stopped, disable the uart and exit
+	*/
+
+	if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
+		s3c24xx_serial_stop_tx(port);
+		goto out;
+	}
+
+	/* try and drain the buffer... */
+
+	while (!uart_circ_empty(xmit) && count-- > 0) {
+		if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
+			break;
+
+		wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
+		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
+		port->icount.tx++;
+	}
+
+	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+		uart_write_wakeup(port);
+
+	if (uart_circ_empty(xmit))
+		s3c24xx_serial_stop_tx(port);
+
+ out:
+	return IRQ_HANDLED;
+}
+
+static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
+{
+	struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
+	unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
+	unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
+
+	if (ufcon & S3C2410_UFCON_FIFOMODE) {
+		if ((ufstat & info->tx_fifomask) != 0 ||
+		    (ufstat & info->tx_fifofull))
+			return 0;
+
+		return 1;
+	}
+
+	return s3c24xx_serial_txempty_nofifo(port);
+}
+
+/* no modem control lines */
+static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
+{
+	unsigned int umstat = rd_regb(port, S3C2410_UMSTAT);
+
+	if (umstat & S3C2410_UMSTAT_CTS)
+		return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
+	else
+		return TIOCM_CAR | TIOCM_DSR;
+}
+
+static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
+{
+	/* todo - possibly remove AFC and do manual CTS */
+}
+
+static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
+{
+	unsigned long flags;
+	unsigned int ucon;
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	ucon = rd_regl(port, S3C2410_UCON);
+
+	if (break_state)
+		ucon |= S3C2410_UCON_SBREAK;
+	else
+		ucon &= ~S3C2410_UCON_SBREAK;
+
+	wr_regl(port, S3C2410_UCON, ucon);
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static void s3c24xx_serial_shutdown(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+
+	if (ourport->tx_claimed) {
+		free_irq(TX_IRQ(port), ourport);
+		tx_enabled(port) = 0;
+		ourport->tx_claimed = 0;
+	}
+
+	if (ourport->rx_claimed) {
+		free_irq(RX_IRQ(port), ourport);
+		ourport->rx_claimed = 0;
+		rx_enabled(port) = 0;
+	}
+}
+
+
+static int s3c24xx_serial_startup(struct uart_port *port)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	int ret;
+
+	dbg("s3c24xx_serial_startup: port=%p (%08lx,%p)\n",
+	    port->mapbase, port->membase);
+
+	rx_enabled(port) = 1;
+
+	ret = request_irq(RX_IRQ(port),
+			  s3c24xx_serial_rx_chars, 0,
+			  s3c24xx_serial_portname(port), ourport);
+
+	if (ret != 0) {
+		printk(KERN_ERR "cannot get irq %d\n", RX_IRQ(port));
+		return ret;
+	}
+
+	ourport->rx_claimed = 1;
+
+	dbg("requesting tx irq...\n");
+
+	tx_enabled(port) = 1;
+
+	ret = request_irq(TX_IRQ(port),
+			  s3c24xx_serial_tx_chars, 0,
+			  s3c24xx_serial_portname(port), ourport);
+
+	if (ret) {
+		printk(KERN_ERR "cannot get irq %d\n", TX_IRQ(port));
+		goto err;
+	}
+
+	ourport->tx_claimed = 1;
+
+	dbg("s3c24xx_serial_startup ok\n");
+
+	/* the port reset code should have done the correct
+	 * register setup for the port controls */
+
+	return ret;
+
+ err:
+	s3c24xx_serial_shutdown(port);
+	return ret;
+}
+
+/* power power management control */
+
+static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
+			      unsigned int old)
+{
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+
+	switch (level) {
+	case 3:
+		if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL)
+			clk_disable(ourport->baudclk);
+
+		clk_disable(ourport->clk);
+		break;
+
+	case 0:
+		clk_enable(ourport->clk);
+
+		if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL)
+			clk_enable(ourport->baudclk);
+
+		break;
+	default:
+		printk(KERN_ERR "s3c24xx_serial: unknown pm %d\n", level);
+	}
+}
+
+/* baud rate calculation
+ *
+ * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
+ * of different sources, including the peripheral clock ("pclk") and an
+ * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
+ * with a programmable extra divisor.
+ *
+ * The following code goes through the clock sources, and calculates the
+ * baud clocks (and the resultant actual baud rates) and then tries to
+ * pick the closest one and select that.
+ *
+*/
+
+
+#define MAX_CLKS (8)
+
+static struct s3c24xx_uart_clksrc tmp_clksrc = {
+	.name		= "pclk",
+	.min_baud	= 0,
+	.max_baud	= 0,
+	.divisor	= 1,
+};
+
+static inline int
+s3c24xx_serial_getsource(struct uart_port *port, struct s3c24xx_uart_clksrc *c)
+{
+	struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
+
+	return (info->get_clksrc)(port, c);
+}
+
+static inline int
+s3c24xx_serial_setsource(struct uart_port *port, struct s3c24xx_uart_clksrc *c)
+{
+	struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
+
+	return (info->set_clksrc)(port, c);
+}
+
+struct baud_calc {
+	struct s3c24xx_uart_clksrc	*clksrc;
+	unsigned int			 calc;
+	unsigned int			 quot;
+	struct clk			*src;
+};
+
+static int s3c24xx_serial_calcbaud(struct baud_calc *calc,
+				   struct uart_port *port,
+				   struct s3c24xx_uart_clksrc *clksrc,
+				   unsigned int baud)
+{
+	unsigned long rate;
+
+	calc->src = clk_get(port->dev, clksrc->name);
+	if (calc->src == NULL || IS_ERR(calc->src))
+		return 0;
+
+	rate = clk_get_rate(calc->src);
+	rate /= clksrc->divisor;
+
+	calc->clksrc = clksrc;
+	calc->quot = (rate + (8 * baud)) / (16 * baud);
+	calc->calc = (rate / (calc->quot * 16));
+
+	calc->quot--;
+	return 1;
+}
+
+static unsigned int s3c24xx_serial_getclk(struct uart_port *port,
+					  struct s3c24xx_uart_clksrc **clksrc,
+					  struct clk **clk,
+					  unsigned int baud)
+{
+	struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
+	struct s3c24xx_uart_clksrc *clkp;
+	struct baud_calc res[MAX_CLKS];
+	struct baud_calc *resptr, *best, *sptr;
+	int i;
+
+	clkp = cfg->clocks;
+	best = NULL;
+
+	if (cfg->clocks_size < 2) {
+		if (cfg->clocks_size == 0)
+			clkp = &tmp_clksrc;
+
+		/* check to see if we're sourcing fclk, and if so we're
+		 * going to have to update the clock source
+		 */
+
+		if (strcmp(clkp->name, "fclk") == 0) {
+			struct s3c24xx_uart_clksrc src;
+
+			s3c24xx_serial_getsource(port, &src);
+
+			/* check that the port already using fclk, and if
+			 * not, then re-select fclk
+			 */
+
+			if (strcmp(src.name, clkp->name) == 0) {
+				s3c24xx_serial_setsource(port, clkp);
+				s3c24xx_serial_getsource(port, &src);
+			}
+
+			clkp->divisor = src.divisor;
+		}
+
+		s3c24xx_serial_calcbaud(res, port, clkp, baud);
+		best = res;
+		resptr = best + 1;
+	} else {
+		resptr = res;
+
+		for (i = 0; i < cfg->clocks_size; i++, clkp++) {
+			if (s3c24xx_serial_calcbaud(resptr, port, clkp, baud))
+				resptr++;
+		}
+	}
+
+	/* ok, we now need to select the best clock we found */
+
+	if (!best) {
+		unsigned int deviation = (1<<30)|((1<<30)-1);
+		int calc_deviation;
+
+		for (sptr = res; sptr < resptr; sptr++) {
+			calc_deviation = baud - sptr->calc;
+			if (calc_deviation < 0)
+				calc_deviation = -calc_deviation;
+
+			if (calc_deviation < deviation) {
+				best = sptr;
+				deviation = calc_deviation;
+			}
+		}
+	}
+
+	/* store results to pass back */
+
+	*clksrc = best->clksrc;
+	*clk    = best->src;
+
+	return best->quot;
+}
+
+static void s3c24xx_serial_set_termios(struct uart_port *port,
+				       struct ktermios *termios,
+				       struct ktermios *old)
+{
+	struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+	struct s3c24xx_uart_clksrc *clksrc = NULL;
+	struct clk *clk = NULL;
+	unsigned long flags;
+	unsigned int baud, quot;
+	unsigned int ulcon;
+	unsigned int umcon;
+
+	/*
+	 * We don't support modem control lines.
+	 */
+	termios->c_cflag &= ~(HUPCL | CMSPAR);
+	termios->c_cflag |= CLOCAL;
+
+	/*
+	 * Ask the core to calculate the divisor for us.
+	 */
+
+	baud = uart_get_baud_rate(port, termios, old, 0, 115200*8);
+
+	if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
+		quot = port->custom_divisor;
+	else
+		quot = s3c24xx_serial_getclk(port, &clksrc, &clk, baud);
+
+	/* check to see if we need  to change clock source */
+
+	if (ourport->clksrc != clksrc || ourport->baudclk != clk) {
+		s3c24xx_serial_setsource(port, clksrc);
+
+		if (ourport->baudclk != NULL && !IS_ERR(ourport->baudclk)) {
+			clk_disable(ourport->baudclk);
+			ourport->baudclk  = NULL;
+		}
+
+		clk_enable(clk);
+
+		ourport->clksrc = clksrc;
+		ourport->baudclk = clk;
+	}
+
+	switch (termios->c_cflag & CSIZE) {
+	case CS5:
+		dbg("config: 5bits/char\n");
+		ulcon = S3C2410_LCON_CS5;
+		break;
+	case CS6:
+		dbg("config: 6bits/char\n");
+		ulcon = S3C2410_LCON_CS6;
+		break;
+	case CS7:
+		dbg("config: 7bits/char\n");
+		ulcon = S3C2410_LCON_CS7;
+		break;
+	case CS8:
+	default:
+		dbg("config: 8bits/char\n");
+		ulcon = S3C2410_LCON_CS8;
+		break;
+	}
+
+	/* preserve original lcon IR settings */
+	ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
+
+	if (termios->c_cflag & CSTOPB)
+		ulcon |= S3C2410_LCON_STOPB;
+
+	umcon = (termios->c_cflag & CRTSCTS) ? S3C2410_UMCOM_AFC : 0;
+
+	if (termios->c_cflag & PARENB) {
+		if (termios->c_cflag & PARODD)
+			ulcon |= S3C2410_LCON_PODD;
+		else
+			ulcon |= S3C2410_LCON_PEVEN;
+	} else {
+		ulcon |= S3C2410_LCON_PNONE;
+	}
+
+	spin_lock_irqsave(&port->lock, flags);
+
+	dbg("setting ulcon to %08x, brddiv to %d\n", ulcon, quot);
+
+	wr_regl(port, S3C2410_ULCON, ulcon);
+	wr_regl(port, S3C2410_UBRDIV, quot);
+	wr_regl(port, S3C2410_UMCON, umcon);
+
+	dbg("uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
+	    rd_regl(port, S3C2410_ULCON),
+	    rd_regl(port, S3C2410_UCON),
+	    rd_regl(port, S3C2410_UFCON));
+
+	/*
+	 * Update the per-port timeout.
+	 */
+	uart_update_timeout(port, termios->c_cflag, baud);
+
+	/*
+	 * Which character status flags are we interested in?
+	 */
+	port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
+	if (termios->c_iflag & INPCK)
+		port->read_status_mask |= S3C2410_UERSTAT_FRAME | S3C2410_UERSTAT_PARITY;
+
+	/*
+	 * Which character status flags should we ignore?
+	 */
+	port->ignore_status_mask = 0;
+	if (termios->c_iflag & IGNPAR)
+		port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
+	if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
+		port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
+
+	/*
+	 * Ignore all characters if CREAD is not set.
+	 */
+	if ((termios->c_cflag & CREAD) == 0)
+		port->ignore_status_mask |= RXSTAT_DUMMY_READ;
+
+	spin_unlock_irqrestore(&port->lock, flags);
+}
+
+static const char *s3c24xx_serial_type(struct uart_port *port)
+{
+	switch (port->type) {
+	case PORT_S3C2410:
+		return "S3C2410";
+	case PORT_S3C2440:
+		return "S3C2440";
+	case PORT_S3C2412:
+		return "S3C2412";
+	default:
+		return NULL;
+	}
+}
+
+#define MAP_SIZE (0x100)
+
+static void s3c24xx_serial_release_port(struct uart_port *port)
+{
+	release_mem_region(port->mapbase, MAP_SIZE);
+}
+
+static int s3c24xx_serial_request_port(struct uart_port *port)
+{
+	const char *name = s3c24xx_serial_portname(port);
+	return request_mem_region(port->mapbase, MAP_SIZE, name) ? 0 : -EBUSY;
+}
+
+static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
+{
+	struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
+
+	if (flags & UART_CONFIG_TYPE &&
+	    s3c24xx_serial_request_port(port) == 0)
+		port->type = info->type;
+}
+
+/*
+ * verify the new serial_struct (for TIOCSSERIAL).
+ */
+static int
+s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
+{
+	struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
+
+	if (ser->type != PORT_UNKNOWN && ser->type != info->type)
+		return -EINVAL;
+
+	return 0;
+}
+
+
+#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
+
+static struct console s3c24xx_serial_console;
+
+#define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
+#else
+#define S3C24XX_SERIAL_CONSOLE NULL
+#endif
+
+static struct uart_ops s3c24xx_serial_ops = {
+	.pm		= s3c24xx_serial_pm,
+	.tx_empty	= s3c24xx_serial_tx_empty,
+	.get_mctrl	= s3c24xx_serial_get_mctrl,
+	.set_mctrl	= s3c24xx_serial_set_mctrl,
+	.stop_tx	= s3c24xx_serial_stop_tx,
+	.start_tx	= s3c24xx_serial_start_tx,
+	.stop_rx	= s3c24xx_serial_stop_rx,
+	.enable_ms	= s3c24xx_serial_enable_ms,
+	.break_ctl	= s3c24xx_serial_break_ctl,
+	.startup	= s3c24xx_serial_startup,
+	.shutdown	= s3c24xx_serial_shutdown,
+	.set_termios	= s3c24xx_serial_set_termios,
+	.type		= s3c24xx_serial_type,
+	.release_port	= s3c24xx_serial_release_port,
+	.request_port	= s3c24xx_serial_request_port,
+	.config_port	= s3c24xx_serial_config_port,
+	.verify_port	= s3c24xx_serial_verify_port,
+};
+
+
+static struct uart_driver s3c24xx_uart_drv = {
+	.owner		= THIS_MODULE,
+	.dev_name	= "s3c2410_serial",
+	.nr		= 3,
+	.cons		= S3C24XX_SERIAL_CONSOLE,
+	.driver_name	= S3C24XX_SERIAL_NAME,
+	.major		= S3C24XX_SERIAL_MAJOR,
+	.minor		= S3C24XX_SERIAL_MINOR,
+};
+
+static struct s3c24xx_uart_port s3c24xx_serial_ports[NR_PORTS] = {
+	[0] = {
+		.port = {
+			.lock		= __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[0].port.lock),
+			.iotype		= UPIO_MEM,
+			.irq		= IRQ_S3CUART_RX0,
+			.uartclk	= 0,
+			.fifosize	= 16,
+			.ops		= &s3c24xx_serial_ops,
+			.flags		= UPF_BOOT_AUTOCONF,
+			.line		= 0,
+		}
+	},
+	[1] = {
+		.port = {
+			.lock		= __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[1].port.lock),
+			.iotype		= UPIO_MEM,
+			.irq		= IRQ_S3CUART_RX1,
+			.uartclk	= 0,
+			.fifosize	= 16,
+			.ops		= &s3c24xx_serial_ops,
+			.flags		= UPF_BOOT_AUTOCONF,
+			.line		= 1,
+		}
+	},
+#if NR_PORTS > 2
+
+	[2] = {
+		.port = {
+			.lock		= __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[2].port.lock),
+			.iotype		= UPIO_MEM,
+			.irq		= IRQ_S3CUART_RX2,
+			.uartclk	= 0,
+			.fifosize	= 16,
+			.ops		= &s3c24xx_serial_ops,
+			.flags		= UPF_BOOT_AUTOCONF,
+			.line		= 2,
+		}
+	}
+#endif
+};
+
+/* s3c24xx_serial_resetport
+ *
+ * wrapper to call the specific reset for this port (reset the fifos
+ * and the settings)
+*/
+
+static inline int s3c24xx_serial_resetport(struct uart_port *port,
+					   struct s3c2410_uartcfg *cfg)
+{
+	struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
+
+	return (info->reset_port)(port, cfg);
+}
+
+/* s3c24xx_serial_init_port
+ *
+ * initialise a single serial port from the platform device given
+ */
+
+static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
+				    struct s3c24xx_uart_info *info,
+				    struct platform_device *platdev)
+{
+	struct uart_port *port = &ourport->port;
+	struct s3c2410_uartcfg *cfg;
+	struct resource *res;
+	int ret;
+
+	dbg("s3c24xx_serial_init_port: port=%p, platdev=%p\n", port, platdev);
+
+	if (platdev == NULL)
+		return -ENODEV;
+
+	cfg = s3c24xx_dev_to_cfg(&platdev->dev);
+
+	if (port->mapbase != 0)
+		return 0;
+
+	if (cfg->hwport > 3)
+		return -EINVAL;
+
+	/* setup info for port */
+	port->dev	= &platdev->dev;
+	ourport->info	= info;
+
+	/* copy the info in from provided structure */
+	ourport->port.fifosize = info->fifosize;
+
+	dbg("s3c24xx_serial_init_port: %p (hw %d)...\n", port, cfg->hwport);
+
+	port->uartclk = 1;
+
+	if (cfg->uart_flags & UPF_CONS_FLOW) {
+		dbg("s3c24xx_serial_init_port: enabling flow control\n");
+		port->flags |= UPF_CONS_FLOW;
+	}
+
+	/* sort our the physical and virtual addresses for each UART */
+
+	res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
+	if (res == NULL) {
+		printk(KERN_ERR "failed to find memory resource for uart\n");
+		return -EINVAL;
+	}
+
+	dbg("resource %p (%lx..%lx)\n", res, res->start, res->end);
+
+	port->mapbase	= res->start;
+	port->membase	= S3C24XX_VA_UART + (res->start - S3C24XX_PA_UART);
+	ret = platform_get_irq(platdev, 0);
+	if (ret < 0)
+		port->irq = 0;
+	else
+		port->irq = ret;
+
+	ourport->clk	= clk_get(&platdev->dev, "uart");
+
+	dbg("port: map=%08x, mem=%08x, irq=%d, clock=%ld\n",
+	    port->mapbase, port->membase, port->irq, port->uartclk);
+
+	/* reset the fifos (and setup the uart) */
+	s3c24xx_serial_resetport(port, cfg);
+	return 0;
+}
+
+static ssize_t s3c24xx_serial_show_clksrc(struct device *dev,
+					  struct device_attribute *attr,
+					  char *buf)
+{
+	struct uart_port *port = s3c24xx_dev_to_port(dev);
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+
+	return snprintf(buf, PAGE_SIZE, "* %s\n", ourport->clksrc->name);
+}
+
+static DEVICE_ATTR(clock_source, S_IRUGO, s3c24xx_serial_show_clksrc, NULL);
+
+/* Device driver serial port probe */
+
+static int probe_index;
+
+int s3c24xx_serial_probe(struct platform_device *dev,
+			 struct s3c24xx_uart_info *info)
+{
+	struct s3c24xx_uart_port *ourport;
+	int ret;
+
+	dbg("s3c24xx_serial_probe(%p, %p) %d\n", dev, info, probe_index);
+
+	ourport = &s3c24xx_serial_ports[probe_index];
+	probe_index++;
+
+	dbg("%s: initialising port %p...\n", __func__, ourport);
+
+	ret = s3c24xx_serial_init_port(ourport, info, dev);
+	if (ret < 0)
+		goto probe_err;
+
+	dbg("%s: adding port\n", __func__);
+	uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
+	platform_set_drvdata(dev, &ourport->port);
+
+	ret = device_create_file(&dev->dev, &dev_attr_clock_source);
+	if (ret < 0)
+		printk(KERN_ERR "%s: failed to add clksrc attr.\n", __func__);
+
+	return 0;
+
+ probe_err:
+	return ret;
+}
+
+EXPORT_SYMBOL_GPL(s3c24xx_serial_probe);
+
+int s3c24xx_serial_remove(struct platform_device *dev)
+{
+	struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
+
+	if (port) {
+		device_remove_file(&dev->dev, &dev_attr_clock_source);
+		uart_remove_one_port(&s3c24xx_uart_drv, port);
+	}
+
+	return 0;
+}
+
+EXPORT_SYMBOL_GPL(s3c24xx_serial_remove);
+
+/* UART power management code */
+
+#ifdef CONFIG_PM
+
+static int s3c24xx_serial_suspend(struct platform_device *dev, pm_message_t state)
+{
+	struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
+
+	if (port)
+		uart_suspend_port(&s3c24xx_uart_drv, port);
+
+	return 0;
+}
+
+static int s3c24xx_serial_resume(struct platform_device *dev)
+{
+	struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
+	struct s3c24xx_uart_port *ourport = to_ourport(port);
+
+	if (port) {
+		clk_enable(ourport->clk);
+		s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
+		clk_disable(ourport->clk);
+
+		uart_resume_port(&s3c24xx_uart_drv, port);
+	}
+
+	return 0;
+}
+#endif
+
+int s3c24xx_serial_init(struct platform_driver *drv,
+			struct s3c24xx_uart_info *info)
+{
+	dbg("s3c24xx_serial_init(%p,%p)\n", drv, info);
+
+#ifdef CONFIG_PM
+	drv->suspend = s3c24xx_serial_suspend;
+	drv->resume = s3c24xx_serial_resume;
+#endif
+
+	return platform_driver_register(drv);
+}
+
+EXPORT_SYMBOL_GPL(s3c24xx_serial_init);
+
+/* module initialisation code */
+
+static int __init s3c24xx_serial_modinit(void)
+{
+	int ret;
+
+	ret = uart_register_driver(&s3c24xx_uart_drv);
+	if (ret < 0) {
+		printk(KERN_ERR "failed to register UART driver\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static void __exit s3c24xx_serial_modexit(void)
+{
+	uart_unregister_driver(&s3c24xx_uart_drv);
+}
+
+module_init(s3c24xx_serial_modinit);
+module_exit(s3c24xx_serial_modexit);
+
+/* Console code */
+
+#ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
+
+static struct uart_port *cons_uart;
+
+static int
+s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
+{
+	struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
+	unsigned long ufstat, utrstat;
+
+	if (ufcon & S3C2410_UFCON_FIFOMODE) {
+		/* fifo mode - check ammount of data in fifo registers... */
+
+		ufstat = rd_regl(port, S3C2410_UFSTAT);
+		return (ufstat & info->tx_fifofull) ? 0 : 1;
+	}
+
+	/* in non-fifo mode, we go and use the tx buffer empty */
+
+	utrstat = rd_regl(port, S3C2410_UTRSTAT);
+	return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
+}
+
+static void
+s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
+{
+	unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);
+	while (!s3c24xx_serial_console_txrdy(port, ufcon))
+		barrier();
+	wr_regb(cons_uart, S3C2410_UTXH, ch);
+}
+
+static void
+s3c24xx_serial_console_write(struct console *co, const char *s,
+			     unsigned int count)
+{
+	uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
+}
+
+static void __init
+s3c24xx_serial_get_options(struct uart_port *port, int *baud,
+			   int *parity, int *bits)
+{
+	struct s3c24xx_uart_clksrc clksrc;
+	struct clk *clk;
+	unsigned int ulcon;
+	unsigned int ucon;
+	unsigned int ubrdiv;
+	unsigned long rate;
+
+	ulcon  = rd_regl(port, S3C2410_ULCON);
+	ucon   = rd_regl(port, S3C2410_UCON);
+	ubrdiv = rd_regl(port, S3C2410_UBRDIV);
+
+	dbg("s3c24xx_serial_get_options: port=%p\n"
+	    "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
+	    port, ulcon, ucon, ubrdiv);
+
+	if ((ucon & 0xf) != 0) {
+		/* consider the serial port configured if the tx/rx mode set */
+
+		switch (ulcon & S3C2410_LCON_CSMASK) {
+		case S3C2410_LCON_CS5:
+			*bits = 5;
+			break;
+		case S3C2410_LCON_CS6:
+			*bits = 6;
+			break;
+		case S3C2410_LCON_CS7:
+			*bits = 7;
+			break;
+		default:
+		case S3C2410_LCON_CS8:
+			*bits = 8;
+			break;
+		}
+
+		switch (ulcon & S3C2410_LCON_PMASK) {
+		case S3C2410_LCON_PEVEN:
+			*parity = 'e';
+			break;
+
+		case S3C2410_LCON_PODD:
+			*parity = 'o';
+			break;
+
+		case S3C2410_LCON_PNONE:
+		default:
+			*parity = 'n';
+		}
+
+		/* now calculate the baud rate */
+
+		s3c24xx_serial_getsource(port, &clksrc);
+
+		clk = clk_get(port->dev, clksrc.name);
+		if (!IS_ERR(clk) && clk != NULL)
+			rate = clk_get_rate(clk) / clksrc.divisor;
+		else
+			rate = 1;
+
+
+		*baud = rate / (16 * (ubrdiv + 1));
+		dbg("calculated baud %d\n", *baud);
+	}
+
+}
+
+/* s3c24xx_serial_init_ports
+ *
+ * initialise the serial ports from the machine provided initialisation
+ * data.
+*/
+
+static int s3c24xx_serial_init_ports(struct s3c24xx_uart_info *info)
+{
+	struct s3c24xx_uart_port *ptr = s3c24xx_serial_ports;
+	struct platform_device **platdev_ptr;
+	int i;
+
+	dbg("s3c24xx_serial_init_ports: initialising ports...\n");
+
+	platdev_ptr = s3c24xx_uart_devs;
+
+	for (i = 0; i < NR_PORTS; i++, ptr++, platdev_ptr++) {
+		s3c24xx_serial_init_port(ptr, info, *platdev_ptr);
+	}
+
+	return 0;
+}
+
+static int __init
+s3c24xx_serial_console_setup(struct console *co, char *options)
+{
+	struct uart_port *port;
+	int baud = 9600;
+	int bits = 8;
+	int parity = 'n';
+	int flow = 'n';
+
+	dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n",
+	    co, co->index, options);
+
+	/* is this a valid port */
+
+	if (co->index == -1 || co->index >= NR_PORTS)
+		co->index = 0;
+
+	port = &s3c24xx_serial_ports[co->index].port;
+
+	/* is the port configured? */
+
+	if (port->mapbase == 0x0) {
+		co->index = 0;
+		port = &s3c24xx_serial_ports[co->index].port;
+	}
+
+	cons_uart = port;
+
+	dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index);
+
+	/*
+	 * Check whether an invalid uart number has been specified, and
+	 * if so, search for the first available port that does have
+	 * console support.
+	 */
+	if (options)
+		uart_parse_options(options, &baud, &parity, &bits, &flow);
+	else
+		s3c24xx_serial_get_options(port, &baud, &parity, &bits);
+
+	dbg("s3c24xx_serial_console_setup: baud %d\n", baud);
+
+	return uart_set_options(port, co, baud, parity, bits, flow);
+}
+
+/* s3c24xx_serial_initconsole
+ *
+ * initialise the console from one of the uart drivers
+*/
+
+static struct console s3c24xx_serial_console = {
+	.name		= S3C24XX_SERIAL_NAME,
+	.device		= uart_console_device,
+	.flags		= CON_PRINTBUFFER,
+	.index		= -1,
+	.write		= s3c24xx_serial_console_write,
+	.setup		= s3c24xx_serial_console_setup
+};
+
+int s3c24xx_serial_initconsole(struct platform_driver *drv,
+			       struct s3c24xx_uart_info *info)
+
+{
+	struct platform_device *dev = s3c24xx_uart_devs[0];
+
+	dbg("s3c24xx_serial_initconsole\n");
+
+	/* select driver based on the cpu */
+
+	if (dev == NULL) {
+		printk(KERN_ERR "s3c24xx: no devices for console init\n");
+		return 0;
+	}
+
+	if (strcmp(dev->name, drv->driver.name) != 0)
+		return 0;
+
+	s3c24xx_serial_console.data = &s3c24xx_uart_drv;
+	s3c24xx_serial_init_ports(info);
+
+	register_console(&s3c24xx_serial_console);
+	return 0;
+}
+
+#endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
+
+MODULE_DESCRIPTION("Samsung SoC Serial port driver");
+MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
+MODULE_LICENSE("GPL v2");