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path: root/drivers/serial/s3c2410.c
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452// SPDX-License-Identifier: GPL-2.0
/*
 * Handling of different ABIs (personalities).
 *
 * We group personalities into execution domains which have their
 * own handlers for kernel entry points, signal mapping, etc...
 *
 * 2001-05-06	Complete rewrite,  Christoph Hellwig (hch@infradead.org)
 */

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/kmod.h>
#include <linux/module.h>
#include <linux/personality.h>
#include <linux/proc_fs.h>
#include <linux/sched.h>
#include <linux/seq_file.h>
#include <linux/syscalls.h>
#include <linux/sysctl.h>
#include <linux/types.h>

#ifdef CONFIG_PROC_FS
static int execdomains_proc_show(struct seq_file *m, void *v)
{
	seq_puts(m, "0-0\tLinux           \t[kernel]\n");
	return 0;
}

static int __init proc_execdomains_init(void)
{
	proc_create_single("execdomains", 0, NULL, execdomains_proc_show);
	return 0;
}
module_init(proc_execdomains_init);
#endif

SYSCALL_DEFINE1(personality, unsigned int, personality)
{
	unsigned int old = current->personality;

	if (personality != 0xffffffff)
		set_personality(personality);

	return old;
}
0'>570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 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/*
 * linux/drivers/serial/s3c2410.c
 *
 * Driver for onboard UARTs on the Samsung S3C24XX
 *
 * Based on drivers/char/serial.c and drivers/char/21285.c
 *
 * Ben Dooks, (c) 2003-2005 Simtec Electronics
 *	http://www.simtec.co.uk/products/SWLINUX/
 *
 * Changelog:
 *
 * 22-Jul-2004  BJD  Finished off device rewrite
 *
 * 21-Jul-2004  BJD  Thanks to <herbet@13thfloor.at> for pointing out
 *                   problems with baud rate and loss of IR settings. Update
 *                   to add configuration via platform_device structure
 *
 * 28-Sep-2004  BJD  Re-write for the following items
 *		     - S3C2410 and S3C2440 serial support
 *		     - Power Management support
 *		     - Fix console via IrDA devices
 *		     - SysReq (Herbert Pötzl)
 *		     - Break character handling (Herbert Pötzl)
 *		     - spin-lock initialisation (Dimitry Andric)
 *		     - added clock control
 *		     - updated init code to use platform_device info
 *
 * 06-Mar-2005  BJD  Add s3c2440 fclk clock source
 *
 * 09-Mar-2005  BJD  Add s3c2400 support
 *
 * 10-Mar-2005  LCVR Changed S3C2410_VA_UART to S3C24XX_VA_UART
*/

/* Note on 2440 fclk clock source handling
 *
 * Whilst it is possible to use the fclk as clock source, the method
 * of properly switching too/from this is currently un-implemented, so
 * whichever way is configured at startup is the one that will be used.
*/

/* 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
*/

#include <linux/config.h>

#if defined(CONFIG_SERIAL_S3C2410_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
#define SUPPORT_SYSRQ
#endif

#include <linux/module.h>
#include <linux/ioport.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/io.h>
#include <asm/irq.h>

#include <asm/hardware.h>

#include <asm/arch/regs-serial.h>
#include <asm/arch/regs-gpio.h>

/* structures */

struct s3c24xx_uart_info {
	char			*name;
	unsigned int		type;
	unsigned int		fifosize;
	unsigned long		rx_fifomask;
	unsigned long		rx_fifoshift;
	unsigned long		rx_fifofull;
	unsigned long		tx_fifomask;
	unsigned long		tx_fifoshift;
	unsigned long		tx_fifofull;

	/* clock source control */

	int (*get_clksrc)(struct uart_port *, struct s3c24xx_uart_clksrc *clk);
	int (*set_clksrc)(struct uart_port *, struct s3c24xx_uart_clksrc *clk);

	/* uart controls */
	int (*reset_port)(struct uart_port *, struct s3c2410_uartcfg *);
};

struct s3c24xx_uart_port {
	unsigned char			rx_claimed;
	unsigned char			tx_claimed;

	struct s3c24xx_uart_info	*info;
	struct s3c24xx_uart_clksrc	*clksrc;
	struct clk			*clk;
	struct clk			*baudclk;
	struct uart_port		port;
};


/* configuration defines */

#if 0
#if 1
/* send debug to the low-level output routines */

extern void printascii(const char *);

static void
s3c24xx_serial_dbg(const char *fmt, ...)
{
	va_list va;
	char buff[256];

	va_start(va, fmt);
	vsprintf(buff, fmt, va);
	va_end(va);

	printascii(buff);
}

#define dbg(x...) s3c24xx_serial_dbg(x)

#else
#define dbg(x...) printk(KERN_DEBUG "s3c24xx: ");
#endif
#else /* no debug */
#define dbg(x...) do {} while(0)
#endif

/* UART name and device definitions */

#define S3C24XX_SERIAL_NAME	"ttySAC"
#define S3C24XX_SERIAL_DEVFS    "tts/"
#define S3C24XX_SERIAL_MAJOR	204
#define S3C24XX_SERIAL_MINOR	64


/* conversion functions */

#define s3c24xx_dev_to_port(__dev) (struct uart_port *)dev_get_drvdata(__dev)
#define s3c24xx_dev_to_cfg(__dev) (struct s3c2410_uartcfg *)((__dev)->platform_data)

/* we can support 3 uarts, but not always use them */

#define NR_PORTS (3)

/* port irq numbers */

#define TX_IRQ(port) ((port)->irq + 1)
#define RX_IRQ(port) ((port)->irq)

/* register access controls */

#define portaddr(port, reg) ((port)->membase + (reg))

#define rd_regb(port, reg) (__raw_readb(portaddr(port, reg)))
#define rd_regl(port, reg) (__raw_readl(portaddr(port, reg)))

#define wr_regb(port, reg, val) \
  do { __raw_writeb(val, portaddr(port, reg)); } while(0)

#define wr_regl(port, reg, val) \
  do { __raw_writel(val, portaddr(port, reg)); } while(0)

/* 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 pt_regs *regs)
{
	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, regs))
			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 pt_regs *regs)
{
	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++) {
			printk(KERN_DEBUG
			       "found clk %p (%s) quot %d, calc %d\n",
			       sptr->clksrc, sptr->clksrc->name,
			       sptr->quot, sptr->calc);

			calc_deviation = baud - sptr->calc;
			if (calc_deviation < 0)
				calc_deviation = -calc_deviation;

			if (calc_deviation < deviation) {
				best = sptr;
				deviation = calc_deviation;
			}
		}

		printk(KERN_DEBUG "best %p (deviation %d)\n", best, deviation);
	}

	printk(KERN_DEBUG "selected clock %p (%s) quot %d, calc %d\n",
	       best->clksrc, best->clksrc->name, best->quot, best->calc);

	/* 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 termios *termios,
				       struct termios *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";
	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_S3C2410_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,
	.devfs_name	= S3C24XX_SERIAL_DEVFS,
	.major		= S3C24XX_SERIAL_MAJOR,
	.minor		= S3C24XX_SERIAL_MINOR,
};

static struct s3c24xx_uart_port s3c24xx_serial_ports[NR_PORTS] = {
	[0] = {
		.port = {
			.lock		= SPIN_LOCK_UNLOCKED,
			.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,
			.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,
			.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;

	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 - S3C2410_PA_UART);
	port->irq	= platform_get_irq(platdev, 0);

	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;
}

/* Device driver serial port probe */

static int probe_index = 0;

static 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", __FUNCTION__, ourport);

	ret = s3c24xx_serial_init_port(ourport, info, dev);
	if (ret < 0)
		goto probe_err;

	dbg("%s: adding port\n", __FUNCTION__);
	uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
	platform_set_drvdata(dev, &ourport->port);

	return 0;

 probe_err:
	return ret;
}

static int s3c24xx_serial_remove(struct platform_device *dev)
{
	struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);

	if (port)
		uart_remove_one_port(&s3c24xx_uart_drv, port);

	return 0;
}

/* 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;
}

#else
#define s3c24xx_serial_suspend NULL
#define s3c24xx_serial_resume  NULL
#endif

static int s3c24xx_serial_init(struct platform_driver *drv,
			       struct s3c24xx_uart_info *info)
{
	dbg("s3c24xx_serial_init(%p,%p)\n", drv, info);
	return platform_driver_register(drv);
}


/* now comes the code to initialise either the s3c2410 or s3c2440 serial
 * port information
*/

/* cpu specific variations on the serial port support */

#ifdef CONFIG_CPU_S3C2400

static int s3c2400_serial_getsource(struct uart_port *port,
				    struct s3c24xx_uart_clksrc *clk)
{
	clk->divisor = 1;
	clk->name = "pclk";

	return 0;
}

static int s3c2400_serial_setsource(struct uart_port *port,
				    struct s3c24xx_uart_clksrc *clk)
{
	return 0;
}

static int s3c2400_serial_resetport(struct uart_port *port,
				    struct s3c2410_uartcfg *cfg)
{
	dbg("s3c2400_serial_resetport: port=%p (%08lx), cfg=%p\n",
	    port, port->mapbase, cfg);

	wr_regl(port, S3C2410_UCON,  cfg->ucon);
	wr_regl(port, S3C2410_ULCON, cfg->ulcon);

	/* reset both fifos */

	wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
	wr_regl(port, S3C2410_UFCON, cfg->ufcon);

	return 0;
}

static struct s3c24xx_uart_info s3c2400_uart_inf = {
	.name		= "Samsung S3C2400 UART",
	.type		= PORT_S3C2400,
	.fifosize	= 16,
	.rx_fifomask	= S3C2410_UFSTAT_RXMASK,
	.rx_fifoshift	= S3C2410_UFSTAT_RXSHIFT,
	.rx_fifofull	= S3C2410_UFSTAT_RXFULL,
	.tx_fifofull	= S3C2410_UFSTAT_TXFULL,
	.tx_fifomask	= S3C2410_UFSTAT_TXMASK,
	.tx_fifoshift	= S3C2410_UFSTAT_TXSHIFT,
	.get_clksrc	= s3c2400_serial_getsource,
	.set_clksrc	= s3c2400_serial_setsource,
	.reset_port	= s3c2400_serial_resetport,
};

static int s3c2400_serial_probe(struct platform_device *dev)
{
	return s3c24xx_serial_probe(dev, &s3c2400_uart_inf);
}

static struct platform_driver s3c2400_serial_drv = {
	.probe		= s3c2400_serial_probe,
	.remove		= s3c24xx_serial_remove,
	.suspend	= s3c24xx_serial_suspend,
	.resume		= s3c24xx_serial_resume,
	.driver		= {
		.name	= "s3c2400-uart",
		.owner	= THIS_MODULE,
	},
};

static inline int s3c2400_serial_init(void)
{
	return s3c24xx_serial_init(&s3c2400_serial_drv, &s3c2400_uart_inf);
}

static inline void s3c2400_serial_exit(void)
{
	platform_driver_unregister(&s3c2400_serial_drv);
}

#define s3c2400_uart_inf_at &s3c2400_uart_inf
#else

static inline int s3c2400_serial_init(void)
{
	return 0;
}

static inline void s3c2400_serial_exit(void)
{
}

#define s3c2400_uart_inf_at NULL

#endif /* CONFIG_CPU_S3C2400 */

/* S3C2410 support */

#ifdef CONFIG_CPU_S3C2410

static int s3c2410_serial_setsource(struct uart_port *port,
				    struct s3c24xx_uart_clksrc *clk)
{
	unsigned long ucon = rd_regl(port, S3C2410_UCON);

	if (strcmp(clk->name, "uclk") == 0)
		ucon |= S3C2410_UCON_UCLK;
	else
		ucon &= ~S3C2410_UCON_UCLK;

	wr_regl(port, S3C2410_UCON, ucon);
	return 0;
}

static int s3c2410_serial_getsource(struct uart_port *port,
				    struct s3c24xx_uart_clksrc *clk)
{
	unsigned long ucon = rd_regl(port, S3C2410_UCON);

	clk->divisor = 1;
	clk->name = (ucon & S3C2410_UCON_UCLK) ? "uclk" : "pclk";

	return 0;
}

static int s3c2410_serial_resetport(struct uart_port *port,
				    struct s3c2410_uartcfg *cfg)
{
	dbg("s3c2410_serial_resetport: port=%p (%08lx), cfg=%p\n",
	    port, port->mapbase, cfg);

	wr_regl(port, S3C2410_UCON,  cfg->ucon);
	wr_regl(port, S3C2410_ULCON, cfg->ulcon);

	/* reset both fifos */

	wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
	wr_regl(port, S3C2410_UFCON, cfg->ufcon);

	return 0;
}

static struct s3c24xx_uart_info s3c2410_uart_inf = {
	.name		= "Samsung S3C2410 UART",
	.type		= PORT_S3C2410,
	.fifosize	= 16,
	.rx_fifomask	= S3C2410_UFSTAT_RXMASK,
	.rx_fifoshift	= S3C2410_UFSTAT_RXSHIFT,
	.rx_fifofull	= S3C2410_UFSTAT_RXFULL,
	.tx_fifofull	= S3C2410_UFSTAT_TXFULL,
	.tx_fifomask	= S3C2410_UFSTAT_TXMASK,
	.tx_fifoshift	= S3C2410_UFSTAT_TXSHIFT,
	.get_clksrc	= s3c2410_serial_getsource,
	.set_clksrc	= s3c2410_serial_setsource,
	.reset_port	= s3c2410_serial_resetport,
};

/* device management */

static int s3c2410_serial_probe(struct platform_device *dev)
{
	return s3c24xx_serial_probe(dev, &s3c2410_uart_inf);
}

static struct platform_driver s3c2410_serial_drv = {
	.probe		= s3c2410_serial_probe,
	.remove		= s3c24xx_serial_remove,
	.suspend	= s3c24xx_serial_suspend,
	.resume		= s3c24xx_serial_resume,
	.driver		= {
		.name	= "s3c2410-uart",
		.owner	= THIS_MODULE,
	},
};

static inline int s3c2410_serial_init(void)
{
	return s3c24xx_serial_init(&s3c2410_serial_drv, &s3c2410_uart_inf);
}

static inline void s3c2410_serial_exit(void)
{
	platform_driver_unregister(&s3c2410_serial_drv);
}

#define s3c2410_uart_inf_at &s3c2410_uart_inf
#else

static inline int s3c2410_serial_init(void)
{
	return 0;
}

static inline void s3c2410_serial_exit(void)
{
}

#define s3c2410_uart_inf_at NULL

#endif /* CONFIG_CPU_S3C2410 */

#ifdef CONFIG_CPU_S3C2440

static int s3c2440_serial_setsource(struct uart_port *port,
				     struct s3c24xx_uart_clksrc *clk)
{
	unsigned long ucon = rd_regl(port, S3C2410_UCON);

	// todo - proper fclk<>nonfclk switch //

	ucon &= ~S3C2440_UCON_CLKMASK;

	if (strcmp(clk->name, "uclk") == 0)
		ucon |= S3C2440_UCON_UCLK;
	else if (strcmp(clk->name, "pclk") == 0)
		ucon |= S3C2440_UCON_PCLK;
	else if (strcmp(clk->name, "fclk") == 0)
		ucon |= S3C2440_UCON_FCLK;
	else {
		printk(KERN_ERR "unknown clock source %s\n", clk->name);
		return -EINVAL;
	}

	wr_regl(port, S3C2410_UCON, ucon);
	return 0;
}


static int s3c2440_serial_getsource(struct uart_port *port,
				    struct s3c24xx_uart_clksrc *clk)
{
	unsigned long ucon = rd_regl(port, S3C2410_UCON);
	unsigned long ucon0, ucon1, ucon2;

	switch (ucon & S3C2440_UCON_CLKMASK) {
	case S3C2440_UCON_UCLK:
		clk->divisor = 1;
		clk->name = "uclk";
		break;

	case S3C2440_UCON_PCLK:
	case S3C2440_UCON_PCLK2:
		clk->divisor = 1;
		clk->name = "pclk";
		break;

	case S3C2440_UCON_FCLK:
		/* the fun of calculating the uart divisors on
		 * the s3c2440 */

		ucon0 = __raw_readl(S3C24XX_VA_UART0 + S3C2410_UCON);
		ucon1 = __raw_readl(S3C24XX_VA_UART1 + S3C2410_UCON);
		ucon2 = __raw_readl(S3C24XX_VA_UART2 + S3C2410_UCON);

		printk("ucons: %08lx, %08lx, %08lx\n", ucon0, ucon1, ucon2);

		ucon0 &= S3C2440_UCON0_DIVMASK;
		ucon1 &= S3C2440_UCON1_DIVMASK;
		ucon2 &= S3C2440_UCON2_DIVMASK;

		if (ucon0 != 0) {
			clk->divisor = ucon0 >> S3C2440_UCON_DIVSHIFT;
			clk->divisor += 6;
		} else if (ucon1 != 0) {
			clk->divisor = ucon1 >> S3C2440_UCON_DIVSHIFT;
			clk->divisor += 21;
		} else if (ucon2 != 0) {
			clk->divisor = ucon2 >> S3C2440_UCON_DIVSHIFT;
			clk->divisor += 36;
		} else {
			/* manual calims 44, seems to be 9 */
			clk->divisor = 9;
		}

		clk->name = "fclk";
		break;
	}

	return 0;
}

static int s3c2440_serial_resetport(struct uart_port *port,
				    struct s3c2410_uartcfg *cfg)
{
	unsigned long ucon = rd_regl(port, S3C2410_UCON);

	dbg("s3c2440_serial_resetport: port=%p (%08lx), cfg=%p\n",
	    port, port->mapbase, cfg);

	/* ensure we don't change the clock settings... */

	ucon &= (S3C2440_UCON0_DIVMASK | (3<<10));

	wr_regl(port, S3C2410_UCON,  ucon | cfg->ucon);
	wr_regl(port, S3C2410_ULCON, cfg->ulcon);

	/* reset both fifos */

	wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
	wr_regl(port, S3C2410_UFCON, cfg->ufcon);

	return 0;
}

static struct s3c24xx_uart_info s3c2440_uart_inf = {
	.name		= "Samsung S3C2440 UART",
	.type		= PORT_S3C2440,
	.fifosize	= 64,
	.rx_fifomask	= S3C2440_UFSTAT_RXMASK,
	.rx_fifoshift	= S3C2440_UFSTAT_RXSHIFT,
	.rx_fifofull	= S3C2440_UFSTAT_RXFULL,
	.tx_fifofull	= S3C2440_UFSTAT_TXFULL,
	.tx_fifomask	= S3C2440_UFSTAT_TXMASK,
	.tx_fifoshift	= S3C2440_UFSTAT_TXSHIFT,
	.get_clksrc	= s3c2440_serial_getsource,
	.set_clksrc	= s3c2440_serial_setsource,
	.reset_port	= s3c2440_serial_resetport,
};

/* device management */

static int s3c2440_serial_probe(struct platform_device *dev)
{
	dbg("s3c2440_serial_probe: dev=%p\n", dev);
	return s3c24xx_serial_probe(dev, &s3c2440_uart_inf);
}

static struct platform_driver s3c2440_serial_drv = {
	.probe		= s3c2440_serial_probe,
	.remove		= s3c24xx_serial_remove,
	.suspend	= s3c24xx_serial_suspend,
	.resume		= s3c24xx_serial_resume,
	.driver		= {
		.name	= "s3c2440-uart",
		.owner	= THIS_MODULE,
	},
};


static inline int s3c2440_serial_init(void)
{
	return s3c24xx_serial_init(&s3c2440_serial_drv, &s3c2440_uart_inf);
}

static inline void s3c2440_serial_exit(void)
{
	platform_driver_unregister(&s3c2440_serial_drv);
}

#define s3c2440_uart_inf_at &s3c2440_uart_inf
#else

static inline int s3c2440_serial_init(void)
{
	return 0;
}

static inline void s3c2440_serial_exit(void)
{
}

#define s3c2440_uart_inf_at NULL
#endif /* CONFIG_CPU_S3C2440 */

/* 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;
	}

	s3c2400_serial_init();
	s3c2410_serial_init();
	s3c2440_serial_init();

	return 0;
}

static void __exit s3c24xx_serial_modexit(void)
{
	s3c2400_serial_exit();
	s3c2410_serial_exit();
	s3c2440_serial_exit();

	uart_unregister_driver(&s3c24xx_uart_drv);
}


module_init(s3c24xx_serial_modinit);
module_exit(s3c24xx_serial_modexit);

/* Console code */

#ifdef CONFIG_SERIAL_S3C2410_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_write(struct console *co, const char *s,
			     unsigned int count)
{
	int i;
	unsigned int ufcon = rd_regl(cons_uart, S3C2410_UFCON);

	for (i = 0; i < count; i++) {
		while (!s3c24xx_serial_console_txrdy(cons_uart, ufcon))
			barrier();

		wr_regb(cons_uart, S3C2410_UTXH, s[i]);

		if (s[i] == '\n') {
			while (!s3c24xx_serial_console_txrdy(cons_uart, ufcon))
				barrier();

			wr_regb(cons_uart, S3C2410_UTXH, '\r');
		}
	}
}

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
};

static int s3c24xx_serial_initconsole(void)
{
	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, "s3c2400-uart") == 0) {
		info = s3c2400_uart_inf_at;
	} else if (strcmp(dev->name, "s3c2410-uart") == 0) {
		info = s3c2410_uart_inf_at;
	} else if (strcmp(dev->name, "s3c2440-uart") == 0) {
		info = s3c2440_uart_inf_at;
	} else {
		printk(KERN_ERR "s3c24xx: no driver for %s\n", dev->name);
		return 0;
	}

	if (info == NULL) {
		printk(KERN_ERR "s3c24xx: no driver for console\n");
		return 0;
	}

	s3c24xx_serial_console.data = &s3c24xx_uart_drv;
	s3c24xx_serial_init_ports(info);

	register_console(&s3c24xx_serial_console);
	return 0;
}

console_initcall(s3c24xx_serial_initconsole);

#endif /* CONFIG_SERIAL_S3C2410_CONSOLE */

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_DESCRIPTION("Samsung S3C2410/S3C2440 Serial port driver");