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[/] [or1k/] [trunk/] [linux/] [linux-2.4/] [drivers/] [char/] [au1x00-serial.c] - Rev 1765

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/*
 *
 * BRIEF MODULE DESCRIPTION
 *	Au1x00 serial port driver.
 *
 * Copyright 2001 MontaVista Software Inc.
 * Author: MontaVista Software, Inc.
 *         	ppopov@mvista.com or source@mvista.com
 *
 *  Derived almost entirely from drivers/char/serial.c:
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *  Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997,
 * 		1998, 1999  Theodore Ts'o
 *
 *  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  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
 *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
 *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
 *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
 *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
 *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 *  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.,
 *  675 Mass Ave, Cambridge, MA 02139, USA.
 */
 
static char *serial_version = "1.01";
static char *serial_revdate = "2001-02-08";
 
 
#include <linux/config.h>
#include <linux/version.h>
 
#undef SERIAL_PARANOIA_CHECK
#define CONFIG_SERIAL_NOPAUSE_IO
#define SERIAL_DO_RESTART
 
 
/* Set of debugging defines */
 
#undef SERIAL_DEBUG_INTR
#undef SERIAL_DEBUG_OPEN
#undef SERIAL_DEBUG_FLOW
#undef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
#undef SERIAL_DEBUG_PCI
#undef SERIAL_DEBUG_AUTOCONF
 
#ifdef MODULE
#undef CONFIG_AU1X00_SERIAL_CONSOLE
#endif
 
#define CONFIG_SERIAL_RSA
 
#define RS_STROBE_TIME (10*HZ)
#define RS_ISR_PASS_LIMIT 256
 
/*
 * End of serial driver configuration section.
 */
 
#include <linux/module.h>
 
#include <linux/types.h>
#ifdef LOCAL_HEADERS
#include "serial_local.h"
#else
#include <linux/serial.h>
#include <linux/serialP.h>
#include <asm/au1000.h>
#include <asm/serial.h>
#define LOCAL_VERSTRING ""
#endif
 
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/timer.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/major.h>
#include <linux/string.h>
#include <linux/fcntl.h>
#include <linux/ptrace.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <asm/uaccess.h>
#include <linux/delay.h>
#ifdef CONFIG_AU1X00_SERIAL_CONSOLE
#include <linux/console.h>
#endif
#ifdef CONFIG_MAGIC_SYSRQ
#include <linux/sysrq.h>
#endif
 
#include <asm/system.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/bitops.h>
 
#ifdef CONFIG_MAC_SERIAL
#define SERIAL_DEV_OFFSET	2
#else
#define SERIAL_DEV_OFFSET	0
#endif
 
#ifdef SERIAL_INLINE
#define _INLINE_ inline
#else
#define _INLINE_
#endif
 
static char *serial_name = "Serial driver";
 
static DECLARE_TASK_QUEUE(tq_serial);
 
static struct tty_driver serial_driver, callout_driver;
static int serial_refcount;
 
static struct timer_list serial_timer;
 
extern unsigned long get_au1x00_uart_baud_base(void);
 
/* serial subtype definitions */
#ifndef SERIAL_TYPE_NORMAL
#define SERIAL_TYPE_NORMAL	1
#define SERIAL_TYPE_CALLOUT	2
#endif
 
/* number of characters left in xmit buffer before we ask for more */
#define WAKEUP_CHARS 256
 
/*
 * IRQ_timeout		- How long the timeout should be for each IRQ
 * 				should be after the IRQ has been active.
 */
 
static struct async_struct *IRQ_ports[NR_IRQS];
static int IRQ_timeout[NR_IRQS];
#ifdef CONFIG_AU1X00_SERIAL_CONSOLE
static struct console sercons;
static int lsr_break_flag;
#endif
#if defined(CONFIG_AU1X00_SERIAL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
static unsigned long break_pressed; /* break, really ... */
#endif
 
static void autoconfig(struct serial_state * state);
static void change_speed(struct async_struct *info, struct termios *old);
static void rs_wait_until_sent(struct tty_struct *tty, int timeout);
 
/*
 * Here we define the default xmit fifo size used for each type of
 * UART
 */
static struct serial_uart_config uart_config[] = {
	{ "unknown", 1, 0 },
	{ "8250", 1, 0 },
	{ "16450", 1, 0 },
	{ "16550", 1, 0 },
	{ 0, 0}
};
 
 
static struct serial_state rs_table[RS_TABLE_SIZE] = {
	SERIAL_PORT_DFNS	/* Defined in serial.h */
};
 
#define NR_PORTS	(sizeof(rs_table)/sizeof(struct serial_state))
 
#ifndef PREPARE_FUNC
#define PREPARE_FUNC(dev)  (dev->prepare)
#define ACTIVATE_FUNC(dev)  (dev->activate)
#define DEACTIVATE_FUNC(dev)  (dev->deactivate)
#endif
 
#define HIGH_BITS_OFFSET ((sizeof(long)-sizeof(int))*8)
 
static struct tty_struct *serial_table[NR_PORTS];
static struct termios *serial_termios[NR_PORTS];
static struct termios *serial_termios_locked[NR_PORTS];
 
 
#if defined(MODULE) && defined(SERIAL_DEBUG_MCOUNT)
#define DBG_CNT(s) printk("(%s): [%x] refc=%d, serc=%d, ttyc=%d -> %s\n", \
 kdevname(tty->device), (info->flags), serial_refcount,info->count,tty->count,s)
#else
#define DBG_CNT(s)
#endif
 
/*
 * tmp_buf is used as a temporary buffer by serial_write.  We need to
 * lock it in case the copy_from_user blocks while swapping in a page,
 * and some other program tries to do a serial write at the same time.
 * Since the lock will only come under contention when the system is
 * swapping and available memory is low, it makes sense to share one
 * buffer across all the serial ports, since it significantly saves
 * memory if large numbers of serial ports are open.
 */
static unsigned char *tmp_buf;
#ifdef DECLARE_MUTEX
static DECLARE_MUTEX(tmp_buf_sem);
#else
static struct semaphore tmp_buf_sem = MUTEX;
#endif
 
static spinlock_t serial_lock = SPIN_LOCK_UNLOCKED;
 
static inline int serial_paranoia_check(struct async_struct *info,
					kdev_t device, const char *routine)
{
#ifdef SERIAL_PARANOIA_CHECK
	static const char *badmagic =
		"Warning: bad magic number for serial struct (%s) in %s\n";
	static const char *badinfo =
		"Warning: null async_struct for (%s) in %s\n";
 
	if (!info) {
		printk(badinfo, kdevname(device), routine);
		return 1;
	}
	if (info->magic != SERIAL_MAGIC) {
		printk(badmagic, kdevname(device), routine);
		return 1;
	}
#endif
	return 0;
}
 
static _INLINE_ unsigned int serial_in(struct async_struct *info, int offset)
{
	return (au_readl(info->port+offset) & 0xffff);
}
 
static _INLINE_ void serial_out(struct async_struct *info, int offset, int value)
{
	au_writel(value & 0xffff, info->port+offset);
}
 
 
/*
 * We used to support using pause I/O for certain machines.  We
 * haven't supported this for a while, but just in case it's badly
 * needed for certain old 386 machines, I've left these #define's
 * in....
 */
#define serial_inp(info, offset)		serial_in(info, offset)
#define serial_outp(info, offset, value)	serial_out(info, offset, value)
 
 
/*
 * ------------------------------------------------------------
 * rs_stop() and rs_start()
 *
 * This routines are called before setting or resetting tty->stopped.
 * They enable or disable transmitter interrupts, as necessary.
 * ------------------------------------------------------------
 */
static void rs_stop(struct tty_struct *tty)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
 
	if (serial_paranoia_check(info, tty->device, "rs_stop"))
		return;
 
	spin_lock_irqsave(&serial_lock, flags);
	if (info->IER & UART_IER_THRI) {
		info->IER &= ~UART_IER_THRI;
		serial_out(info, UART_IER, info->IER);
	}
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
static void rs_start(struct tty_struct *tty)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
 
	if (serial_paranoia_check(info, tty->device, "rs_start"))
		return;
 
	spin_lock_irqsave(&serial_lock, flags);
	if (info->xmit.head != info->xmit.tail
	    && info->xmit.buf
	    && !(info->IER & UART_IER_THRI)) {
		info->IER |= UART_IER_THRI;
		serial_out(info, UART_IER, info->IER);
	}
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
/*
 * ----------------------------------------------------------------------
 *
 * Here starts the interrupt handling routines.  All of the following
 * subroutines are declared as inline and are folded into
 * rs_interrupt().  They were separated out for readability's sake.
 *
 * Note: rs_interrupt() is a "fast" interrupt, which means that it
 * runs with interrupts turned off.  People who may want to modify
 * rs_interrupt() should try to keep the interrupt handler as fast as
 * possible.  After you are done making modifications, it is not a bad
 * idea to do:
 *
 * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer serial.c
 *
 * and look at the resulting assemble code in serial.s.
 *
 * 				- Ted Ts'o (tytso@mit.edu), 7-Mar-93
 * -----------------------------------------------------------------------
 */
 
/*
 * This routine is used by the interrupt handler to schedule
 * processing in the software interrupt portion of the driver.
 */
static _INLINE_ void rs_sched_event(struct async_struct *info,
				  int event)
{
	info->event |= 1 << event;
	queue_task(&info->tqueue, &tq_serial);
	mark_bh(SERIAL_BH);
}
 
static _INLINE_ void receive_chars(struct async_struct *info,
				 int *status, struct pt_regs * regs)
{
	struct tty_struct *tty = info->tty;
	unsigned char ch;
	int ignored = 0;
	struct	async_icount *icount;
 
	icount = &info->state->icount;
	do {
		ch = serial_inp(info, UART_RX);
		if (tty->flip.count >= TTY_FLIPBUF_SIZE)
			goto ignore_char;
		*tty->flip.char_buf_ptr = ch;
		icount->rx++;
 
#ifdef SERIAL_DEBUG_INTR
		printk("DR%02x:%02x...", ch, *status);
#endif
		*tty->flip.flag_buf_ptr = 0;
		if (*status & (UART_LSR_BI | UART_LSR_PE |
			       UART_LSR_FE | UART_LSR_OE)) {
			/*
			 * For statistics only
			 */
			if (*status & UART_LSR_BI) {
				*status &= ~(UART_LSR_FE | UART_LSR_PE);
				icount->brk++;
				/*
				 * We do the SysRQ and SAK checking
				 * here because otherwise the break
				 * may get masked by ignore_status_mask
				 * or read_status_mask.
				 */
#if defined(CONFIG_AU1X00_SERIAL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
				if (info->line == sercons.index) {
					if (!break_pressed) {
						break_pressed = jiffies;
						goto ignore_char;
					}
					break_pressed = 0;
				}
#endif
				if (info->flags & ASYNC_SAK)
					do_SAK(tty);
			} else if (*status & UART_LSR_PE)
				icount->parity++;
			else if (*status & UART_LSR_FE)
				icount->frame++;
			if (*status & UART_LSR_OE)
				icount->overrun++;
 
			/*
			 * Now check to see if character should be
			 * ignored, and mask off conditions which
			 * should be ignored.
			 */
			if (*status & info->ignore_status_mask) {
				if (++ignored > 100)
					break;
				goto ignore_char;
			}
			*status &= info->read_status_mask;
 
#ifdef CONFIG_AU1X00_SERIAL_CONSOLE
			if (info->line == sercons.index) {
				/* Recover the break flag from console xmit */
				*status |= lsr_break_flag;
				lsr_break_flag = 0;
			}
#endif
			if (*status & (UART_LSR_BI)) {
#ifdef SERIAL_DEBUG_INTR
				printk("handling break....");
#endif
				*tty->flip.flag_buf_ptr = TTY_BREAK;
			} else if (*status & UART_LSR_PE)
				*tty->flip.flag_buf_ptr = TTY_PARITY;
			else if (*status & UART_LSR_FE)
				*tty->flip.flag_buf_ptr = TTY_FRAME;
			if (*status & UART_LSR_OE) {
				/*
				 * Overrun is special, since it's
				 * reported immediately, and doesn't
				 * affect the current character
				 */
				tty->flip.count++;
				tty->flip.flag_buf_ptr++;
				tty->flip.char_buf_ptr++;
				*tty->flip.flag_buf_ptr = TTY_OVERRUN;
				if (tty->flip.count >= TTY_FLIPBUF_SIZE)
					goto ignore_char;
			}
		}
#if defined(CONFIG_AU1X00_SERIAL_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
		if (break_pressed && info->line == sercons.index) {
			if (ch != 0 &&
			    time_before(jiffies, break_pressed + HZ*5)) {
				handle_sysrq(ch, regs, NULL, NULL);
				break_pressed = 0;
				goto ignore_char;
			}
			break_pressed = 0;
		}
#endif
		tty->flip.flag_buf_ptr++;
		tty->flip.char_buf_ptr++;
		tty->flip.count++;
	ignore_char:
		*status = serial_inp(info, UART_LSR);
	} while (*status & UART_LSR_DR);
	tty_flip_buffer_push(tty);
}
 
static _INLINE_ void transmit_chars(struct async_struct *info, int *intr_done)
{
	int count;
 
	if (info->x_char) {
		serial_outp(info, UART_TX, info->x_char);
		info->state->icount.tx++;
		info->x_char = 0;
		if (intr_done)
			*intr_done = 0;
		return;
	}
	if (info->xmit.head == info->xmit.tail
	    || info->tty->stopped
	    || info->tty->hw_stopped) {
		info->IER &= ~UART_IER_THRI;
		serial_out(info, UART_IER, info->IER);
		return;
	}
 
	count = info->xmit_fifo_size;
	do {
		serial_out(info, UART_TX, info->xmit.buf[info->xmit.tail]);
		info->xmit.tail = (info->xmit.tail + 1) & (SERIAL_XMIT_SIZE-1);
		info->state->icount.tx++;
		if (info->xmit.head == info->xmit.tail)
			break;
	} while (--count > 0);
 
	if (CIRC_CNT(info->xmit.head,
		     info->xmit.tail,
		     SERIAL_XMIT_SIZE) < WAKEUP_CHARS)
		rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
 
#ifdef SERIAL_DEBUG_INTR
	printk("THRE...");
#endif
	if (intr_done)
		*intr_done = 0;
 
	if (info->xmit.head == info->xmit.tail) {
		info->IER &= ~UART_IER_THRI;
		serial_out(info, UART_IER, info->IER);
	}
}
 
static _INLINE_ void check_modem_status(struct async_struct *info)
{
	int	status;
	struct	async_icount *icount;
 
	status = serial_in(info, UART_MSR);
 
	if (status & UART_MSR_ANY_DELTA) {
		icount = &info->state->icount;
		/* update input line counters */
		if (status & UART_MSR_TERI)
			icount->rng++;
		if (status & UART_MSR_DDSR)
			icount->dsr++;
		if (status & UART_MSR_DDCD) {
			icount->dcd++;
#ifdef CONFIG_HARD_PPS
			if ((info->flags & ASYNC_HARDPPS_CD) &&
			    (status & UART_MSR_DCD))
				hardpps();
#endif
		}
		if (status & UART_MSR_DCTS)
			icount->cts++;
		wake_up_interruptible(&info->delta_msr_wait);
	}
 
	if ((info->flags & ASYNC_CHECK_CD) && (status & UART_MSR_DDCD)) {
#if (defined(SERIAL_DEBUG_OPEN) || defined(SERIAL_DEBUG_INTR))
		printk("ttys%d CD now %s...", info->line,
		       (status & UART_MSR_DCD) ? "on" : "off");
#endif
		if (status & UART_MSR_DCD)
			wake_up_interruptible(&info->open_wait);
		else if (!((info->flags & ASYNC_CALLOUT_ACTIVE) &&
			   (info->flags & ASYNC_CALLOUT_NOHUP))) {
#ifdef SERIAL_DEBUG_OPEN
			printk("doing serial hangup...");
#endif
			if (info->tty)
				tty_hangup(info->tty);
		}
	}
	if (info->flags & ASYNC_CTS_FLOW) {
		if (info->tty->hw_stopped) {
			if (status & UART_MSR_CTS) {
#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
				printk("CTS tx start...");
#endif
				info->tty->hw_stopped = 0;
				info->IER |= UART_IER_THRI;
				serial_out(info, UART_IER, info->IER);
				rs_sched_event(info, RS_EVENT_WRITE_WAKEUP);
				return;
			}
		} else {
			if (!(status & UART_MSR_CTS)) {
#if (defined(SERIAL_DEBUG_INTR) || defined(SERIAL_DEBUG_FLOW))
				printk("CTS tx stop...");
#endif
				info->tty->hw_stopped = 1;
				info->IER &= ~UART_IER_THRI;
				serial_out(info, UART_IER, info->IER);
			}
		}
	}
}
 
 
 
/*
 * This is the serial driver's interrupt routine for a single port
 */
static void rs_interrupt_single(int irq, void *dev_id, struct pt_regs * regs)
{
	int status;
	int pass_counter = 0;
	struct async_struct * info;
 
#ifdef SERIAL_DEBUG_INTR
	printk("rs_interrupt_single(%d)...", irq);
#endif
 
	info = IRQ_ports[irq];
	if (!info || !info->tty)
		return;
 
	do {
		status = serial_inp(info, UART_LSR);
#ifdef SERIAL_DEBUG_INTR
		printk("status = %x...", status);
#endif
		if (status & UART_LSR_DR)
			receive_chars(info, &status, regs);
		check_modem_status(info);
		if (status & UART_LSR_THRE)
			transmit_chars(info, 0);
		if (pass_counter++ > RS_ISR_PASS_LIMIT) {
#if 0
			printk("rs_single loop break.\n");
#endif
			break;
		}
	} while (!(serial_in(info, UART_IIR) & UART_IIR_NO_INT));
	info->last_active = jiffies;
#ifdef SERIAL_DEBUG_INTR
	printk("end.\n");
#endif
}
 
 
/*
 * -------------------------------------------------------------------
 * Here ends the serial interrupt routines.
 * -------------------------------------------------------------------
 */
 
/*
 * This routine is used to handle the "bottom half" processing for the
 * serial driver, known also the "software interrupt" processing.
 * This processing is done at the kernel interrupt level, after the
 * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON.  This
 * is where time-consuming activities which can not be done in the
 * interrupt driver proper are done; the interrupt driver schedules
 * them using rs_sched_event(), and they get done here.
 */
static void do_serial_bh(void)
{
	run_task_queue(&tq_serial);
}
 
static void do_softint(void *private_)
{
	struct async_struct	*info = (struct async_struct *) private_;
	struct tty_struct	*tty;
 
	tty = info->tty;
	if (!tty)
		return;
 
	if (test_and_clear_bit(RS_EVENT_WRITE_WAKEUP, &info->event)) {
		if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
		    tty->ldisc.write_wakeup)
			(tty->ldisc.write_wakeup)(tty);
		wake_up_interruptible(&tty->write_wait);
#ifdef SERIAL_HAVE_POLL_WAIT
		wake_up_interruptible(&tty->poll_wait);
#endif
	}
}
 
/*
 * This subroutine is called when the RS_TIMER goes off.  It is used
 * by the serial driver to handle ports that do not have an interrupt
 * (irq=0).  This doesn't work very well for 16450's, but gives barely
 * passable results for a 16550A.  (Although at the expense of much
 * CPU overhead).
 */
static void rs_timer(unsigned long dummy)
{
	static unsigned long last_strobe;
	struct async_struct *info;
	unsigned int	i;
	unsigned long flags;
 
	if ((jiffies - last_strobe) >= RS_STROBE_TIME) {
		for (i=0; i < NR_IRQS; i++) {
			info = IRQ_ports[i];
			if (!info)
				continue;
			spin_lock_irqsave(&serial_lock, flags);
				rs_interrupt_single(i, NULL, NULL);
				spin_unlock_irqrestore(&serial_lock, flags);
		}
	}
	last_strobe = jiffies;
	mod_timer(&serial_timer, jiffies + RS_STROBE_TIME);
 
#if 0
	if (IRQ_ports[0]) {
		spin_lock_irqsave(&serial_lock, flags);
		rs_interrupt_single(0, NULL, NULL);
		spin_unlock_irqrestore(&serial_lock, flags);
 
		mod_timer(&serial_timer, jiffies + IRQ_timeout[0]);
	}
#endif
}
 
/*
 * ---------------------------------------------------------------
 * Low level utility subroutines for the serial driver:  routines to
 * figure out the appropriate timeout for an interrupt chain, routines
 * to initialize and startup a serial port, and routines to shutdown a
 * serial port.  Useful stuff like that.
 * ---------------------------------------------------------------
 */
 
/*
 * This routine figures out the correct timeout for a particular IRQ.
 * It uses the smallest timeout of all of the serial ports in a
 * particular interrupt chain.  Now only used for IRQ 0....
 */
static void figure_IRQ_timeout(int irq)
{
	struct	async_struct	*info;
	int	timeout = 60*HZ;	/* 60 seconds === a long time :-) */
 
	info = IRQ_ports[irq];
	if (!info) {
		IRQ_timeout[irq] = 60*HZ;
		return;
	}
	while (info) {
		if (info->timeout < timeout)
			timeout = info->timeout;
		info = info->next_port;
	}
	if (!irq)
		timeout = timeout / 2;
	IRQ_timeout[irq] = (timeout > 3) ? timeout-2 : 1;
}
 
 
static int startup(struct async_struct * info)
{
	unsigned long flags;
	int	retval=0;
	void (*handler)(int, void *, struct pt_regs *);
	struct serial_state *state= info->state;
	unsigned long page;
 
	page = get_zeroed_page(GFP_KERNEL);
	if (!page)
		return -ENOMEM;
 
	spin_lock_irqsave(&serial_lock, flags);
 
	if (info->flags & ASYNC_INITIALIZED) {
		free_page(page);
		goto errout;
	}
 
	if (!CONFIGURED_SERIAL_PORT(state) || !state->type) {
		if (info->tty)
			set_bit(TTY_IO_ERROR, &info->tty->flags);
		free_page(page);
		goto errout;
	}
	if (info->xmit.buf)
		free_page(page);
	else
		info->xmit.buf = (unsigned char *) page;
 
 
	if (au_readl(UART_MOD_CNTRL + state->port) != 0x3) {
		au_writel(3, UART_MOD_CNTRL + state->port);
		au_sync_delay(10);
	}
#ifdef SERIAL_DEBUG_OPEN
	printk("starting up ttys%d (irq %d)...", info->line, state->irq);
#endif
 
 
	/*
	 * Clear the FIFO buffers and disable them
	 * (they will be reenabled in change_speed())
	 */
	if (uart_config[state->type].flags & UART_CLEAR_FIFO) {
		serial_outp(info, UART_FCR, UART_FCR_ENABLE_FIFO);
		serial_outp(info, UART_FCR, (UART_FCR_ENABLE_FIFO |
					     UART_FCR_CLEAR_RCVR |
					     UART_FCR_CLEAR_XMIT));
		serial_outp(info, UART_FCR, 0);
	}
 
	/*
	 * Clear the interrupt registers.
	 */
	(void) serial_inp(info, UART_LSR);
	(void) serial_inp(info, UART_RX);
	(void) serial_inp(info, UART_IIR);
	(void) serial_inp(info, UART_MSR);
 
	/*
	 * At this point there's no way the LSR could still be 0xFF;
	 * if it is, then bail out, because there's likely no UART
	 * here.
	 */
	if (!(info->flags & ASYNC_BUGGY_UART) &&
	    (serial_inp(info, UART_LSR) == 0xff)) {
		printk("LSR safety check engaged!\n");
		if (capable(CAP_SYS_ADMIN)) {
			if (info->tty)
				set_bit(TTY_IO_ERROR, &info->tty->flags);
		} else
			retval = -ENODEV;
		goto errout;
	}
 
	/*
	 * Allocate the IRQ if necessary
	 */
#if 0
	/* au1000, uart0 irq is 0 */
	if (state->irq && (!IRQ_ports[state->irq] || !IRQ_ports[state->irq]->next_port)) {
#endif
	if ((!IRQ_ports[state->irq] || !IRQ_ports[state->irq]->next_port)) {
		if (IRQ_ports[state->irq]) {
			retval = -EBUSY;
			goto errout;
		} else
			handler = rs_interrupt_single;
 
		retval = request_irq(state->irq, handler, SA_SHIRQ,
				     "serial", &IRQ_ports[state->irq]);
		if (retval) {
			if (capable(CAP_SYS_ADMIN)) {
				if (info->tty)
					set_bit(TTY_IO_ERROR,
						&info->tty->flags);
				retval = 0;
			}
			goto errout;
		}
	}
 
	/*
	 * Insert serial port into IRQ chain.
	 */
	info->prev_port = 0;
	info->next_port = IRQ_ports[state->irq];
	if (info->next_port)
		info->next_port->prev_port = info;
	IRQ_ports[state->irq] = info;
	figure_IRQ_timeout(state->irq);
 
	/*
	 * Now, initialize the UART
	 */
	serial_outp(info, UART_LCR, UART_LCR_WLEN8);
 
	info->MCR = 0;
	if (info->tty->termios->c_cflag & CBAUD)
		info->MCR = UART_MCR_DTR | UART_MCR_RTS;
	{
		if (state->irq != 0)
			info->MCR |= UART_MCR_OUT2;
	}
	info->MCR |= ALPHA_KLUDGE_MCR; 		/* Don't ask */
	serial_outp(info, UART_MCR, info->MCR);
 
	/*
	 * Finally, enable interrupts
	 */
	info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI;
	serial_outp(info, UART_IER, info->IER);	/* enable interrupts */
 
 
	/*
	 * And clear the interrupt registers again for luck.
	 */
	(void)serial_inp(info, UART_LSR);
	(void)serial_inp(info, UART_RX);
	(void)serial_inp(info, UART_IIR);
	(void)serial_inp(info, UART_MSR);
 
	if (info->tty)
		clear_bit(TTY_IO_ERROR, &info->tty->flags);
	info->xmit.head = info->xmit.tail = 0;
 
	/*
	 * Set up serial timers...
	 */
	mod_timer(&serial_timer, jiffies + 2*HZ/100);
 
	/*
	 * Set up the tty->alt_speed kludge
	 */
	if (info->tty) {
		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
			info->tty->alt_speed = 57600;
		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
			info->tty->alt_speed = 115200;
		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
			info->tty->alt_speed = 230400;
		if ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
			info->tty->alt_speed = 460800;
	}
 
	/*
	 * and set the speed of the serial port
	 */
	change_speed(info, 0);
 
	info->flags |= ASYNC_INITIALIZED;
	spin_unlock_irqrestore(&serial_lock, flags);
	return 0;
 
errout:
	spin_unlock_irqrestore(&serial_lock, flags);
	return retval;
}
 
/*
 * This routine will shutdown a serial port; interrupts are disabled, and
 * DTR is dropped if the hangup on close termio flag is on.
 */
static void shutdown(struct async_struct * info)
{
	unsigned long	flags;
	struct serial_state *state;
	int		retval;
 
	if (!(info->flags & ASYNC_INITIALIZED))
		return;
 
	state = info->state;
 
#ifdef SERIAL_DEBUG_OPEN
	printk("Shutting down serial port %d (irq %d)....", info->line,
	       state->irq);
#endif
 
	spin_lock_irqsave(&serial_lock, flags);
 
	/*
	 * clear delta_msr_wait queue to avoid mem leaks: we may free the irq
	 * here so the queue might never be waken up
	 */
	wake_up_interruptible(&info->delta_msr_wait);
 
	/*
	 * First unlink the serial port from the IRQ chain...
	 */
	if (info->next_port)
		info->next_port->prev_port = info->prev_port;
	if (info->prev_port)
		info->prev_port->next_port = info->next_port;
	else
		IRQ_ports[state->irq] = info->next_port;
	figure_IRQ_timeout(state->irq);
 
	/*
	 * Free the IRQ, if necessary
	 */
//	if (state->irq && (!IRQ_ports[state->irq] ||
	if ((!IRQ_ports[state->irq] ||
			  !IRQ_ports[state->irq]->next_port)) {
		if (IRQ_ports[state->irq]) {
			free_irq(state->irq, &IRQ_ports[state->irq]);
			retval = request_irq(state->irq, rs_interrupt_single,
					     SA_SHIRQ, "serial",
					     &IRQ_ports[state->irq]);
 
			if (retval)
				printk("serial shutdown: request_irq: error %d"
				       "  Couldn't reacquire IRQ.\n", retval);
		} else
			free_irq(state->irq, &IRQ_ports[state->irq]);
	}
 
	if (info->xmit.buf) {
		unsigned long pg = (unsigned long) info->xmit.buf;
		info->xmit.buf = 0;
		free_page(pg);
	}
 
	info->IER = 0;
	serial_outp(info, UART_IER, 0x00);	/* disable all intrs */
		info->MCR &= ~UART_MCR_OUT2;
	info->MCR |= ALPHA_KLUDGE_MCR; 		/* Don't ask */
 
	/* disable break condition */
	serial_out(info, UART_LCR, serial_inp(info, UART_LCR) & ~UART_LCR_SBC);
 
	if (!info->tty || (info->tty->termios->c_cflag & HUPCL))
		info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
	serial_outp(info, UART_MCR, info->MCR);
 
	/* disable FIFO's */
	serial_outp(info, UART_FCR, (UART_FCR_ENABLE_FIFO |
				     UART_FCR_CLEAR_RCVR |
				     UART_FCR_CLEAR_XMIT));
	serial_outp(info, UART_FCR, 0);
 
	(void)serial_in(info, UART_RX);    /* read data port to reset things */
 
	if (info->tty)
		set_bit(TTY_IO_ERROR, &info->tty->flags);
 
	info->flags &= ~ASYNC_INITIALIZED;
#ifndef CONFIG_KGDB
	au_writel(0, UART_MOD_CNTRL + state->port);
	au_sync_delay(10);
#endif
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
 
/*
 * This routine is called to set the UART divisor registers to match
 * the specified baud rate for a serial port.
 */
static void change_speed(struct async_struct *info,
			 struct termios *old_termios)
{
	int	quot = 0, baud_base, baud;
	unsigned cflag, cval, fcr = 0;
	int	bits;
	unsigned long	flags;
 
	if (!info->tty || !info->tty->termios)
		return;
	cflag = info->tty->termios->c_cflag;
	if (!CONFIGURED_SERIAL_PORT(info))
		return;
 
	/* byte size and parity */
	switch (cflag & CSIZE) {
	      case CS5: cval = 0x00; bits = 7; break;
	      case CS6: cval = 0x01; bits = 8; break;
	      case CS7: cval = 0x02; bits = 9; break;
	      case CS8: cval = 0x03; bits = 10; break;
	      /* Never happens, but GCC is too dumb to figure it out */
	      default:  cval = 0x00; bits = 7; break;
	      }
	if (cflag & CSTOPB) {
		cval |= 0x04;
		bits++;
	}
	if (cflag & PARENB) {
		cval |= UART_LCR_PARITY;
		bits++;
	}
	if (!(cflag & PARODD))
		cval |= UART_LCR_EPAR;
#ifdef CMSPAR
	if (cflag & CMSPAR)
		cval |= UART_LCR_SPAR;
#endif
 
	/* Determine divisor based on baud rate */
	baud = tty_get_baud_rate(info->tty);
	if (!baud) {
		baud = 9600;	/* B0 transition handled in rs_set_termios */
	}
	baud_base = get_au1x00_uart_baud_base();
 
	//if (baud == 38400 &&
	if (((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)) {
		quot = info->state->custom_divisor;
	}
	else {
		if (baud == 134)
			/* Special case since 134 is really 134.5 */
			quot = (2*baud_base / 269);
		else if (baud)
			quot = baud_base / baud;
	}
	/* If the quotient is zero refuse the change */
	if (!quot && old_termios) {
		info->tty->termios->c_cflag &= ~CBAUD;
		info->tty->termios->c_cflag |= (old_termios->c_cflag & CBAUD);
		baud = tty_get_baud_rate(info->tty);
		if (!baud)
			baud = 9600;
		if (baud == 38400 &&
		    ((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST))
			quot = info->state->custom_divisor;
		else {
			if (baud == 134)
				/* Special case since 134 is really 134.5 */
				quot = (2*baud_base / 269);
			else if (baud)
				quot = baud_base / baud;
		}
	}
	/* As a last resort, if the quotient is zero, default to 9600 bps */
	if (!quot)
		quot = baud_base / 9600;
 
	info->quot = quot;
	info->timeout = ((info->xmit_fifo_size*HZ*bits*quot) / baud_base);
	info->timeout += HZ/50;		/* Add .02 seconds of slop */
 
	/* Set up FIFO's */
	if (uart_config[info->state->type].flags & UART_USE_FIFO) {
		if ((info->state->baud_base / quot) < 2400)
			fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_1;
		else
			fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIGGER_8;
	}
 
	/* CTS flow control flag and modem status interrupts */
	info->IER &= ~UART_IER_MSI;
	if (info->flags & ASYNC_HARDPPS_CD)
		info->IER |= UART_IER_MSI;
	if (cflag & CRTSCTS) {
		info->flags |= ASYNC_CTS_FLOW;
		info->IER |= UART_IER_MSI;
	} else
		info->flags &= ~ASYNC_CTS_FLOW;
	if (cflag & CLOCAL)
		info->flags &= ~ASYNC_CHECK_CD;
	else {
		info->flags |= ASYNC_CHECK_CD;
		info->IER |= UART_IER_MSI;
	}
	serial_out(info, UART_IER, info->IER);
 
	/*
	 * Set up parity check flag
	 */
#define RELEVANT_IFLAG(iflag) (iflag & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
 
	info->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
	if (I_INPCK(info->tty))
		info->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
	if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
		info->read_status_mask |= UART_LSR_BI;
 
	/*
	 * Characters to ignore
	 */
	info->ignore_status_mask = 0;
	if (I_IGNPAR(info->tty))
		info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
	if (I_IGNBRK(info->tty)) {
		info->ignore_status_mask |= UART_LSR_BI;
		/*
		 * If we're ignore parity and break indicators, ignore
		 * overruns too.  (For real raw support).
		 */
		if (I_IGNPAR(info->tty))
			info->ignore_status_mask |= UART_LSR_OE;
	}
	/*
	 * !!! ignore all characters if CREAD is not set
	 */
	if ((cflag & CREAD) == 0)
		info->ignore_status_mask |= UART_LSR_DR;
	spin_lock_irqsave(&serial_lock, flags);
 
	serial_outp(info, UART_CLK, quot & 0xffff);
	serial_outp(info, UART_LCR, cval);
	info->LCR = cval;				/* Save LCR */
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
static void rs_put_char(struct tty_struct *tty, unsigned char ch)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
 
	if (serial_paranoia_check(info, tty->device, "rs_put_char"))
		return;
 
	if (!tty || !info->xmit.buf)
		return;
 
	spin_lock_irqsave(&serial_lock, flags);
	if (CIRC_SPACE(info->xmit.head,
		       info->xmit.tail,
		       SERIAL_XMIT_SIZE) == 0) {
		spin_unlock_irqrestore(&serial_lock, flags);
		return;
	}
 
	info->xmit.buf[info->xmit.head] = ch;
	info->xmit.head = (info->xmit.head + 1) & (SERIAL_XMIT_SIZE-1);
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
static void rs_flush_chars(struct tty_struct *tty)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
 
	if (serial_paranoia_check(info, tty->device, "rs_flush_chars"))
		return;
 
	if (info->xmit.head == info->xmit.tail
	    || tty->stopped
	    || tty->hw_stopped
	    || !info->xmit.buf)
		return;
 
	spin_lock_irqsave(&serial_lock, flags);
	info->IER |= UART_IER_THRI;
	serial_out(info, UART_IER, info->IER);
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
static int rs_write(struct tty_struct * tty, int from_user,
		    const unsigned char *buf, int count)
{
	int	c, ret = 0;
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
 
	if (serial_paranoia_check(info, tty->device, "rs_write"))
		return 0;
 
	if (!tty || !info->xmit.buf || !tmp_buf)
		return 0;
 
	spin_lock_irqsave(&serial_lock, flags);
	if (from_user) {
		down(&tmp_buf_sem);
		while (1) {
			int c1;
			c = CIRC_SPACE_TO_END(info->xmit.head,
					      info->xmit.tail,
					      SERIAL_XMIT_SIZE);
			if (count < c)
				c = count;
			if (c <= 0)
				break;
 
			c -= copy_from_user(tmp_buf, buf, c);
			if (!c) {
				if (!ret)
					ret = -EFAULT;
				break;
			}
			cli();
			c1 = CIRC_SPACE_TO_END(info->xmit.head,
					       info->xmit.tail,
					       SERIAL_XMIT_SIZE);
			if (c1 < c)
				c = c1;
			memcpy(info->xmit.buf + info->xmit.head, tmp_buf, c);
			info->xmit.head = ((info->xmit.head + c) &
					   (SERIAL_XMIT_SIZE-1));
			spin_unlock_irqrestore(&serial_lock, flags);
			buf += c;
			count -= c;
			ret += c;
		}
		up(&tmp_buf_sem);
	} else {
		cli();
		while (1) {
			c = CIRC_SPACE_TO_END(info->xmit.head,
					      info->xmit.tail,
					      SERIAL_XMIT_SIZE);
			if (count < c)
				c = count;
			if (c <= 0) {
				break;
			}
			memcpy(info->xmit.buf + info->xmit.head, buf, c);
			info->xmit.head = ((info->xmit.head + c) &
					   (SERIAL_XMIT_SIZE-1));
			buf += c;
			count -= c;
			ret += c;
		}
		spin_unlock_irqrestore(&serial_lock, flags);
	}
	if (info->xmit.head != info->xmit.tail
	    && !tty->stopped
	    && !tty->hw_stopped
	    && !(info->IER & UART_IER_THRI)) {
		info->IER |= UART_IER_THRI;
		serial_out(info, UART_IER, info->IER);
	}
	return ret;
}
 
static int rs_write_room(struct tty_struct *tty)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
 
	if (serial_paranoia_check(info, tty->device, "rs_write_room"))
		return 0;
	return CIRC_SPACE(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}
 
static int rs_chars_in_buffer(struct tty_struct *tty)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
 
	if (serial_paranoia_check(info, tty->device, "rs_chars_in_buffer"))
		return 0;
	return CIRC_CNT(info->xmit.head, info->xmit.tail, SERIAL_XMIT_SIZE);
}
 
static void rs_flush_buffer(struct tty_struct *tty)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
 
	if (serial_paranoia_check(info, tty->device, "rs_flush_buffer"))
		return;
	spin_lock_irqsave(&serial_lock, flags);
	info->xmit.head = info->xmit.tail = 0;
	spin_unlock_irqrestore(&serial_lock, flags);
	wake_up_interruptible(&tty->write_wait);
#ifdef SERIAL_HAVE_POLL_WAIT
	wake_up_interruptible(&tty->poll_wait);
#endif
	if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
	    tty->ldisc.write_wakeup)
		(tty->ldisc.write_wakeup)(tty);
}
 
/*
 * This function is used to send a high-priority XON/XOFF character to
 * the device
 */
static void rs_send_xchar(struct tty_struct *tty, char ch)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
 
	if (serial_paranoia_check(info, tty->device, "rs_send_char"))
		return;
 
	info->x_char = ch;
	if (ch) {
		/* Make sure transmit interrupts are on */
		info->IER |= UART_IER_THRI;
		serial_out(info, UART_IER, info->IER);
	}
}
 
/*
 * ------------------------------------------------------------
 * rs_throttle()
 *
 * This routine is called by the upper-layer tty layer to signal that
 * incoming characters should be throttled.
 * ------------------------------------------------------------
 */
static void rs_throttle(struct tty_struct * tty)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
#ifdef SERIAL_DEBUG_THROTTLE
	char	buf[64];
 
	printk("throttle %s: %d....\n", tty_name(tty, buf),
	       tty->ldisc.chars_in_buffer(tty));
#endif
 
	if (serial_paranoia_check(info, tty->device, "rs_throttle"))
		return;
 
	if (I_IXOFF(tty))
		rs_send_xchar(tty, STOP_CHAR(tty));
 
	if (tty->termios->c_cflag & CRTSCTS)
		info->MCR &= ~UART_MCR_RTS;
 
	spin_lock_irqsave(&serial_lock, flags);
	serial_out(info, UART_MCR, info->MCR);
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
static void rs_unthrottle(struct tty_struct * tty)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
#ifdef SERIAL_DEBUG_THROTTLE
	char	buf[64];
 
	printk("unthrottle %s: %d....\n", tty_name(tty, buf),
	       tty->ldisc.chars_in_buffer(tty));
#endif
 
	if (serial_paranoia_check(info, tty->device, "rs_unthrottle"))
		return;
 
	if (I_IXOFF(tty)) {
		if (info->x_char)
			info->x_char = 0;
		else
			rs_send_xchar(tty, START_CHAR(tty));
	}
	if (tty->termios->c_cflag & CRTSCTS)
		info->MCR |= UART_MCR_RTS;
	spin_lock_irqsave(&serial_lock, flags);
	serial_out(info, UART_MCR, info->MCR);
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
/*
 * ------------------------------------------------------------
 * rs_ioctl() and friends
 * ------------------------------------------------------------
 */
 
static int get_serial_info(struct async_struct * info,
			   struct serial_struct * retinfo)
{
	struct serial_struct tmp;
	struct serial_state *state = info->state;
 
	if (!retinfo)
		return -EFAULT;
	memset(&tmp, 0, sizeof(tmp));
	tmp.type = state->type;
	tmp.line = state->line;
	tmp.port = state->port;
	if (HIGH_BITS_OFFSET)
		tmp.port_high = state->port >> HIGH_BITS_OFFSET;
	else
		tmp.port_high = 0;
	tmp.irq = state->irq;
	tmp.flags = state->flags;
	tmp.xmit_fifo_size = state->xmit_fifo_size;
	tmp.baud_base = state->baud_base;
	tmp.close_delay = state->close_delay;
	tmp.closing_wait = state->closing_wait;
	tmp.custom_divisor = state->custom_divisor;
	tmp.hub6 = state->hub6;
	tmp.io_type = state->io_type;
	if (copy_to_user(retinfo,&tmp,sizeof(*retinfo)))
		return -EFAULT;
	return 0;
}
 
static int set_serial_info(struct async_struct * info,
			   struct serial_struct * new_info)
{
	struct serial_struct new_serial;
 	struct serial_state old_state, *state;
	unsigned int		i,change_irq,change_port;
	int 			retval = 0;
	unsigned long		new_port;
 
	if (copy_from_user(&new_serial,new_info,sizeof(new_serial)))
		return -EFAULT;
	state = info->state;
	old_state = *state;
 
	new_port = new_serial.port;
	if (HIGH_BITS_OFFSET)
		new_port += (unsigned long) new_serial.port_high << HIGH_BITS_OFFSET;
 
	change_irq = new_serial.irq != state->irq;
	change_port = (new_port != ((int) state->port)) ||
		(new_serial.hub6 != state->hub6);
 
	if (!capable(CAP_SYS_ADMIN)) {
		if (change_irq || change_port ||
		    (new_serial.baud_base != state->baud_base) ||
		    (new_serial.type != state->type) ||
		    (new_serial.close_delay != state->close_delay) ||
		    (new_serial.xmit_fifo_size != state->xmit_fifo_size) ||
		    ((new_serial.flags & ~ASYNC_USR_MASK) !=
		     (state->flags & ~ASYNC_USR_MASK)))
			return -EPERM;
		state->flags = ((state->flags & ~ASYNC_USR_MASK) |
			       (new_serial.flags & ASYNC_USR_MASK));
		info->flags = ((info->flags & ~ASYNC_USR_MASK) |
			       (new_serial.flags & ASYNC_USR_MASK));
		state->custom_divisor = new_serial.custom_divisor;
		goto check_and_exit;
	}
 
	new_serial.irq = irq_cannonicalize(new_serial.irq);
 
	if ((new_serial.irq >= NR_IRQS) || (new_serial.irq < 0) ||
	    (new_serial.baud_base < 9600)|| (new_serial.type < PORT_UNKNOWN) ||
	    (new_serial.type > PORT_MAX) || (new_serial.type == PORT_CIRRUS) ||
	    (new_serial.type == PORT_STARTECH)) {
		return -EINVAL;
	}
 
	if ((new_serial.type != state->type) ||
	    (new_serial.xmit_fifo_size <= 0))
		new_serial.xmit_fifo_size =
			uart_config[new_serial.type].dfl_xmit_fifo_size;
 
	/* Make sure address is not already in use */
	if (new_serial.type) {
		for (i = 0 ; i < NR_PORTS; i++)
			if ((state != &rs_table[i]) &&
			    (rs_table[i].port == new_port) &&
			    rs_table[i].type)
				return -EADDRINUSE;
	}
 
	if ((change_port || change_irq) && (state->count > 1))
		return -EBUSY;
 
	/*
	 * OK, past this point, all the error checking has been done.
	 * At this point, we start making changes.....
	 */
 
	state->baud_base = new_serial.baud_base;
	state->flags = ((state->flags & ~ASYNC_FLAGS) |
			(new_serial.flags & ASYNC_FLAGS));
	info->flags = ((state->flags & ~ASYNC_INTERNAL_FLAGS) |
		       (info->flags & ASYNC_INTERNAL_FLAGS));
	state->custom_divisor = new_serial.custom_divisor;
	state->close_delay = new_serial.close_delay * HZ/100;
	state->closing_wait = new_serial.closing_wait * HZ/100;
	info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
	info->xmit_fifo_size = state->xmit_fifo_size =
		new_serial.xmit_fifo_size;
 
	if ((state->type != PORT_UNKNOWN) && state->port) {
		release_region(state->port,8);
	}
	state->type = new_serial.type;
	if (change_port || change_irq) {
		/*
		 * We need to shutdown the serial port at the old
		 * port/irq combination.
		 */
		shutdown(info);
		state->irq = new_serial.irq;
		info->port = state->port = new_port;
		info->hub6 = state->hub6 = new_serial.hub6;
		if (info->hub6)
			info->io_type = state->io_type = SERIAL_IO_HUB6;
		else if (info->io_type == SERIAL_IO_HUB6)
			info->io_type = state->io_type = SERIAL_IO_PORT;
	}
	if ((state->type != PORT_UNKNOWN) && state->port) {
			request_region(state->port,8,"serial(set)");
	}
 
 
check_and_exit:
	if (!state->port || !state->type)
		return 0;
	if (info->flags & ASYNC_INITIALIZED) {
		if (((old_state.flags & ASYNC_SPD_MASK) !=
		     (state->flags & ASYNC_SPD_MASK)) ||
		    (old_state.custom_divisor != state->custom_divisor)) {
			if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
				info->tty->alt_speed = 57600;
			if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
				info->tty->alt_speed = 115200;
			if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
				info->tty->alt_speed = 230400;
			if ((state->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
				info->tty->alt_speed = 460800;
			change_speed(info, 0);
		}
	} else {
		retval = startup(info);
	}
	return retval;
}
 
 
/*
 * get_lsr_info - get line status register info
 *
 * Purpose: Let user call ioctl() to get info when the UART physically
 * 	    is emptied.  On bus types like RS485, the transmitter must
 * 	    release the bus after transmitting. This must be done when
 * 	    the transmit shift register is empty, not be done when the
 * 	    transmit holding register is empty.  This functionality
 * 	    allows an RS485 driver to be written in user space.
 */
static int get_lsr_info(struct async_struct * info, unsigned int *value)
{
	unsigned char status;
	unsigned int result;
	unsigned long flags;
 
	spin_lock_irqsave(&serial_lock, flags);
	status = serial_in(info, UART_LSR);
	spin_unlock_irqrestore(&serial_lock, flags);
	result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT : 0);
 
	/*
	 * If we're about to load something into the transmit
	 * register, we'll pretend the transmitter isn't empty to
	 * avoid a race condition (depending on when the transmit
	 * interrupt happens).
	 */
	if (info->x_char ||
	    ((CIRC_CNT(info->xmit.head, info->xmit.tail,
		       SERIAL_XMIT_SIZE) > 0) &&
	     !info->tty->stopped && !info->tty->hw_stopped))
		result &= TIOCSER_TEMT;
 
	if (copy_to_user(value, &result, sizeof(int)))
		return -EFAULT;
	return 0;
}
 
 
static int get_modem_info(struct async_struct * info, unsigned int *value)
{
	unsigned char control, status;
	unsigned int result;
	unsigned long flags;
 
	control = info->MCR;
	spin_lock_irqsave(&serial_lock, flags);
	status = serial_in(info, UART_MSR);
	spin_unlock_irqrestore(&serial_lock, flags);
	result =  ((control & UART_MCR_RTS) ? TIOCM_RTS : 0)
		| ((control & UART_MCR_DTR) ? TIOCM_DTR : 0)
#ifdef TIOCM_OUT1
		| ((control & UART_MCR_OUT1) ? TIOCM_OUT1 : 0)
		| ((control & UART_MCR_OUT2) ? TIOCM_OUT2 : 0)
#endif
		| ((status  & UART_MSR_DCD) ? TIOCM_CAR : 0)
		| ((status  & UART_MSR_RI) ? TIOCM_RNG : 0)
		| ((status  & UART_MSR_DSR) ? TIOCM_DSR : 0)
		| ((status  & UART_MSR_CTS) ? TIOCM_CTS : 0);
 
	if (copy_to_user(value, &result, sizeof(int)))
		return -EFAULT;
	return 0;
}
 
static int set_modem_info(struct async_struct * info, unsigned int cmd,
			  unsigned int *value)
{
	unsigned int arg;
	unsigned long flags;
 
	if (copy_from_user(&arg, value, sizeof(int)))
		return -EFAULT;
 
	switch (cmd) {
	case TIOCMBIS:
		if (arg & TIOCM_RTS)
			info->MCR |= UART_MCR_RTS;
		if (arg & TIOCM_DTR)
			info->MCR |= UART_MCR_DTR;
#ifdef TIOCM_OUT1
		if (arg & TIOCM_OUT1)
			info->MCR |= UART_MCR_OUT1;
		if (arg & TIOCM_OUT2)
			info->MCR |= UART_MCR_OUT2;
#endif
		if (arg & TIOCM_LOOP)
			info->MCR |= UART_MCR_LOOP;
		break;
	case TIOCMBIC:
		if (arg & TIOCM_RTS)
			info->MCR &= ~UART_MCR_RTS;
		if (arg & TIOCM_DTR)
			info->MCR &= ~UART_MCR_DTR;
#ifdef TIOCM_OUT1
		if (arg & TIOCM_OUT1)
			info->MCR &= ~UART_MCR_OUT1;
		if (arg & TIOCM_OUT2)
			info->MCR &= ~UART_MCR_OUT2;
#endif
		if (arg & TIOCM_LOOP)
			info->MCR &= ~UART_MCR_LOOP;
		break;
	case TIOCMSET:
		info->MCR = ((info->MCR & ~(UART_MCR_RTS |
#ifdef TIOCM_OUT1
					    UART_MCR_OUT1 |
					    UART_MCR_OUT2 |
#endif
					    UART_MCR_LOOP |
					    UART_MCR_DTR))
			     | ((arg & TIOCM_RTS) ? UART_MCR_RTS : 0)
#ifdef TIOCM_OUT1
			     | ((arg & TIOCM_OUT1) ? UART_MCR_OUT1 : 0)
			     | ((arg & TIOCM_OUT2) ? UART_MCR_OUT2 : 0)
#endif
			     | ((arg & TIOCM_LOOP) ? UART_MCR_LOOP : 0)
			     | ((arg & TIOCM_DTR) ? UART_MCR_DTR : 0));
		break;
	default:
		return -EINVAL;
	}
	spin_lock_irqsave(&serial_lock, flags);
	info->MCR |= ALPHA_KLUDGE_MCR; 		/* Don't ask */
	serial_out(info, UART_MCR, info->MCR);
	spin_unlock_irqrestore(&serial_lock, flags);
	return 0;
}
 
static int do_autoconfig(struct async_struct * info)
{
	int retval;
 
	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;
 
	if (info->state->count > 1)
		return -EBUSY;
 
	shutdown(info);
 
	autoconfig(info->state);
	retval = startup(info);
	if (retval)
		return retval;
	return 0;
}
 
/*
 * rs_break() --- routine which turns the break handling on or off
 */
static void rs_break(struct tty_struct *tty, int break_state)
{
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
 
	if (serial_paranoia_check(info, tty->device, "rs_break"))
		return;
 
	if (!CONFIGURED_SERIAL_PORT(info))
		return;
	spin_lock_irqsave(&serial_lock, flags);
	if (break_state == -1)
		info->LCR |= UART_LCR_SBC;
	else
		info->LCR &= ~UART_LCR_SBC;
	serial_out(info, UART_LCR, info->LCR);
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
 
static int rs_ioctl(struct tty_struct *tty, struct file * file,
		    unsigned int cmd, unsigned long arg)
{
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	struct async_icount cprev, cnow;	/* kernel counter temps */
	struct serial_icounter_struct icount;
	unsigned long flags;
 
	if (serial_paranoia_check(info, tty->device, "rs_ioctl"))
		return -ENODEV;
 
	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
		if (tty->flags & (1 << TTY_IO_ERROR))
		    return -EIO;
	}
 
	switch (cmd) {
		case TIOCMGET:
			return get_modem_info(info, (unsigned int *) arg);
		case TIOCMBIS:
		case TIOCMBIC:
		case TIOCMSET:
			return set_modem_info(info, cmd, (unsigned int *) arg);
		case TIOCGSERIAL:
			return get_serial_info(info,
					       (struct serial_struct *) arg);
		case TIOCSSERIAL:
			return set_serial_info(info,
					       (struct serial_struct *) arg);
		case TIOCSERCONFIG:
			return do_autoconfig(info);
 
		case TIOCSERGETLSR: /* Get line status register */
			return get_lsr_info(info, (unsigned int *) arg);
 
		case TIOCSERGSTRUCT:
			if (copy_to_user((struct async_struct *) arg,
					 info, sizeof(struct async_struct)))
				return -EFAULT;
			return 0;
 
 
		/*
		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
		 * - mask passed in arg for lines of interest
 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
		 * Caller should use TIOCGICOUNT to see which one it was
		 */
		case TIOCMIWAIT:
			spin_lock_irqsave(&serial_lock, flags);
			/* note the counters on entry */
			cprev = info->state->icount;
			spin_unlock_irqrestore(&serial_lock, flags);
			/* Force modem status interrupts on */
			info->IER |= UART_IER_MSI;
			serial_out(info, UART_IER, info->IER);
			while (1) {
				interruptible_sleep_on(&info->delta_msr_wait);
				/* see if a signal did it */
				if (signal_pending(current))
					return -ERESTARTSYS;
				spin_lock_irqsave(&serial_lock, flags);
				cnow = info->state->icount; /* atomic copy */
				spin_unlock_irqrestore(&serial_lock, flags);
				if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
				    cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
					return -EIO; /* no change => error */
				if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
				     ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
				     ((arg & TIOCM_CD)  && (cnow.dcd != cprev.dcd)) ||
				     ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
					return 0;
				}
				cprev = cnow;
			}
			/* NOTREACHED */
 
		/*
		 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
		 * Return: write counters to the user passed counter struct
		 * NB: both 1->0 and 0->1 transitions are counted except for
		 *     RI where only 0->1 is counted.
		 */
		case TIOCGICOUNT:
			spin_lock_irqsave(&serial_lock, flags);
			cnow = info->state->icount;
			spin_unlock_irqrestore(&serial_lock, flags);
			icount.cts = cnow.cts;
			icount.dsr = cnow.dsr;
			icount.rng = cnow.rng;
			icount.dcd = cnow.dcd;
			icount.rx = cnow.rx;
			icount.tx = cnow.tx;
			icount.frame = cnow.frame;
			icount.overrun = cnow.overrun;
			icount.parity = cnow.parity;
			icount.brk = cnow.brk;
			icount.buf_overrun = cnow.buf_overrun;
 
			if (copy_to_user((void *)arg, &icount, sizeof(icount)))
				return -EFAULT;
			return 0;
		case TIOCSERGWILD:
		case TIOCSERSWILD:
			/* "setserial -W" is called in Debian boot */
			printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
			return 0;
 
		default:
			return -ENOIOCTLCMD;
		}
	return 0;
}
 
static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned long flags;
	unsigned int cflag = tty->termios->c_cflag;
 
	if (   (cflag == old_termios->c_cflag)
	    && (   RELEVANT_IFLAG(tty->termios->c_iflag)
		== RELEVANT_IFLAG(old_termios->c_iflag)))
	  return;
 
	change_speed(info, old_termios);
 
	/* Handle transition to B0 status */
	if ((old_termios->c_cflag & CBAUD) &&
	    !(cflag & CBAUD)) {
		info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
		spin_lock_irqsave(&serial_lock, flags);
		serial_out(info, UART_MCR, info->MCR);
		spin_unlock_irqrestore(&serial_lock, flags);
	}
 
	/* Handle transition away from B0 status */
	if (!(old_termios->c_cflag & CBAUD) &&
	    (cflag & CBAUD)) {
		info->MCR |= UART_MCR_DTR;
		if (!(tty->termios->c_cflag & CRTSCTS) ||
		    !test_bit(TTY_THROTTLED, &tty->flags)) {
			info->MCR |= UART_MCR_RTS;
		}
		spin_lock_irqsave(&serial_lock, flags);
		serial_out(info, UART_MCR, info->MCR);
		spin_unlock_irqrestore(&serial_lock, flags);
	}
 
	/* Handle turning off CRTSCTS */
	if ((old_termios->c_cflag & CRTSCTS) &&
	    !(tty->termios->c_cflag & CRTSCTS)) {
		tty->hw_stopped = 0;
		rs_start(tty);
	}
}
 
/*
 * ------------------------------------------------------------
 * rs_close()
 *
 * This routine is called when the serial port gets closed.  First, we
 * wait for the last remaining data to be sent.  Then, we unlink its
 * async structure from the interrupt chain if necessary, and we free
 * that IRQ if nothing is left in the chain.
 * ------------------------------------------------------------
 */
static void rs_close(struct tty_struct *tty, struct file * filp)
{
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	struct serial_state *state;
	unsigned long flags;
 
	if (!info || serial_paranoia_check(info, tty->device, "rs_close"))
		return;
 
	state = info->state;
 
	spin_lock_irqsave(&serial_lock, flags);
 
	if (tty_hung_up_p(filp)) {
		DBG_CNT("before DEC-hung");
		MOD_DEC_USE_COUNT;
		spin_unlock_irqrestore(&serial_lock, flags);
		return;
	}
 
#ifdef SERIAL_DEBUG_OPEN
	printk("rs_close ttys%d, count = %d\n", info->line, state->count);
#endif
	if ((tty->count == 1) && (state->count != 1)) {
		/*
		 * Uh, oh.  tty->count is 1, which means that the tty
		 * structure will be freed.  state->count should always
		 * be one in these conditions.  If it's greater than
		 * one, we've got real problems, since it means the
		 * serial port won't be shutdown.
		 */
		printk("rs_close: bad serial port count; tty->count is 1, "
		       "state->count is %d\n", state->count);
		state->count = 1;
	}
	if (--state->count < 0) {
		printk("rs_close: bad serial port count for ttys%d: %d\n",
		       info->line, state->count);
		state->count = 0;
	}
	if (state->count) {
		DBG_CNT("before DEC-2");
		MOD_DEC_USE_COUNT;
		spin_unlock_irqrestore(&serial_lock, flags);
		return;
	}
	info->flags |= ASYNC_CLOSING;
	spin_unlock_irqrestore(&serial_lock, flags);
	/*
	 * Save the termios structure, since this port may have
	 * separate termios for callout and dialin.
	 */
	if (info->flags & ASYNC_NORMAL_ACTIVE)
		info->state->normal_termios = *tty->termios;
	if (info->flags & ASYNC_CALLOUT_ACTIVE)
		info->state->callout_termios = *tty->termios;
	/*
	 * Now we wait for the transmit buffer to clear; and we notify
	 * the line discipline to only process XON/XOFF characters.
	 */
	tty->closing = 1;
	if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
		tty_wait_until_sent(tty, info->closing_wait);
	/*
	 * At this point we stop accepting input.  To do this, we
	 * disable the receive line status interrupts, and tell the
	 * interrupt driver to stop checking the data ready bit in the
	 * line status register.
	 */
	info->IER &= ~UART_IER_RLSI;
	info->read_status_mask &= ~UART_LSR_DR;
	if (info->flags & ASYNC_INITIALIZED) {
		serial_out(info, UART_IER, info->IER);
		/*
		 * Before we drop DTR, make sure the UART transmitter
		 * has completely drained; this is especially
		 * important if there is a transmit FIFO!
		 */
		rs_wait_until_sent(tty, info->timeout);
	}
	shutdown(info);
	if (tty->driver.flush_buffer)
		tty->driver.flush_buffer(tty);
	if (tty->ldisc.flush_buffer)
		tty->ldisc.flush_buffer(tty);
	tty->closing = 0;
	info->event = 0;
	info->tty = 0;
	if (info->blocked_open) {
		if (info->close_delay) {
			set_current_state(TASK_INTERRUPTIBLE);
			schedule_timeout(info->close_delay);
		}
		wake_up_interruptible(&info->open_wait);
	}
	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
			 ASYNC_CLOSING);
	wake_up_interruptible(&info->close_wait);
	MOD_DEC_USE_COUNT;
}
 
/*
 * rs_wait_until_sent() --- wait until the transmitter is empty
 */
static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
{
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	unsigned long orig_jiffies, char_time;
	int lsr;
 
	if (serial_paranoia_check(info, tty->device, "rs_wait_until_sent"))
		return;
 
	if (info->state->type == PORT_UNKNOWN)
		return;
 
	if (info->xmit_fifo_size == 0)
		return; /* Just in case.... */
 
	orig_jiffies = jiffies;
	/*
	 * Set the check interval to be 1/5 of the estimated time to
	 * send a single character, and make it at least 1.  The check
	 * interval should also be less than the timeout.
	 *
	 * Note: we have to use pretty tight timings here to satisfy
	 * the NIST-PCTS.
	 */
	char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
	char_time = char_time / 5;
	if (char_time == 0)
		char_time = 1;
	if (timeout && timeout < char_time)
		char_time = timeout;
	/*
	 * If the transmitter hasn't cleared in twice the approximate
	 * amount of time to send the entire FIFO, it probably won't
	 * ever clear.  This assumes the UART isn't doing flow
	 * control, which is currently the case.  Hence, if it ever
	 * takes longer than info->timeout, this is probably due to a
	 * UART bug of some kind.  So, we clamp the timeout parameter at
	 * 2*info->timeout.
	 */
	if (!timeout || timeout > 2*info->timeout)
		timeout = 2*info->timeout;
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
	printk("In rs_wait_until_sent(%d) check=%lu...", timeout, char_time);
	printk("jiff=%lu...", jiffies);
#endif
	while (!((lsr = serial_inp(info, UART_LSR)) & UART_LSR_TEMT)) {
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
		printk("lsr = %d (jiff=%lu)...", lsr, jiffies);
#endif
		set_current_state(TASK_INTERRUPTIBLE);
		schedule_timeout(char_time);
		if (signal_pending(current))
			break;
		if (timeout && time_after(jiffies, orig_jiffies + timeout))
			break;
	}
	set_current_state(TASK_RUNNING);
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
	printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
#endif
}
 
/*
 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
 */
static void rs_hangup(struct tty_struct *tty)
{
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	struct serial_state *state = info->state;
 
	if (serial_paranoia_check(info, tty->device, "rs_hangup"))
		return;
 
	state = info->state;
 
	rs_flush_buffer(tty);
	if (info->flags & ASYNC_CLOSING)
		return;
	shutdown(info);
	info->event = 0;
	state->count = 0;
	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
	info->tty = 0;
	wake_up_interruptible(&info->open_wait);
}
 
/*
 * ------------------------------------------------------------
 * rs_open() and friends
 * ------------------------------------------------------------
 */
static int block_til_ready(struct tty_struct *tty, struct file * filp,
			   struct async_struct *info)
{
	DECLARE_WAITQUEUE(wait, current);
	struct serial_state *state = info->state;
	int		retval;
	int		do_clocal = 0, extra_count = 0;
	unsigned long	flags;
 
	/*
	 * If the device is in the middle of being closed, then block
	 * until it's done, and then try again.
	 */
	if (tty_hung_up_p(filp) ||
	    (info->flags & ASYNC_CLOSING)) {
		if (info->flags & ASYNC_CLOSING)
			interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
		return ((info->flags & ASYNC_HUP_NOTIFY) ?
			-EAGAIN : -ERESTARTSYS);
#else
		return -EAGAIN;
#endif
	}
 
	/*
	 * If this is a callout device, then just make sure the normal
	 * device isn't being used.
	 */
	if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
		if (info->flags & ASYNC_NORMAL_ACTIVE)
			return -EBUSY;
		if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
		    (info->flags & ASYNC_SESSION_LOCKOUT) &&
		    (info->session != current->session))
		    return -EBUSY;
		if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
		    (info->flags & ASYNC_PGRP_LOCKOUT) &&
		    (info->pgrp != current->pgrp))
		    return -EBUSY;
		info->flags |= ASYNC_CALLOUT_ACTIVE;
		return 0;
	}
 
	/*
	 * If non-blocking mode is set, or the port is not enabled,
	 * then make the check up front and then exit.
	 */
	if ((filp->f_flags & O_NONBLOCK) ||
	    (tty->flags & (1 << TTY_IO_ERROR))) {
		if (info->flags & ASYNC_CALLOUT_ACTIVE)
			return -EBUSY;
		info->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}
 
	if (info->flags & ASYNC_CALLOUT_ACTIVE) {
		if (state->normal_termios.c_cflag & CLOCAL)
			do_clocal = 1;
	} else {
		if (tty->termios->c_cflag & CLOCAL)
			do_clocal = 1;
	}
 
	/*
	 * Block waiting for the carrier detect and the line to become
	 * free (i.e., not in use by the callout).  While we are in
	 * this loop, state->count is dropped by one, so that
	 * rs_close() knows when to free things.  We restore it upon
	 * exit, either normal or abnormal.
	 */
	retval = 0;
	add_wait_queue(&info->open_wait, &wait);
#ifdef SERIAL_DEBUG_OPEN
	printk("block_til_ready before block: ttys%d, count = %d\n",
	       state->line, state->count);
#endif
	spin_lock_irqsave(&serial_lock, flags);
	if (!tty_hung_up_p(filp)) {
		extra_count = 1;
		state->count--;
	}
	spin_unlock_irqrestore(&serial_lock, flags);
	info->blocked_open++;
	while (1) {
		spin_lock_irqsave(&serial_lock, flags);
		if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
		    (tty->termios->c_cflag & CBAUD))
			serial_out(info, UART_MCR,
				   serial_inp(info, UART_MCR) |
				   (UART_MCR_DTR | UART_MCR_RTS));
		spin_unlock_irqrestore(&serial_lock, flags);
		set_current_state(TASK_INTERRUPTIBLE);
		if (tty_hung_up_p(filp) ||
		    !(info->flags & ASYNC_INITIALIZED)) {
#ifdef SERIAL_DO_RESTART
			if (info->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;
#else
			retval = -EAGAIN;
#endif
			break;
		}
		if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
		    !(info->flags & ASYNC_CLOSING) &&
		    (do_clocal || (serial_in(info, UART_MSR) &
				   UART_MSR_DCD)))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
#ifdef SERIAL_DEBUG_OPEN
		printk("block_til_ready blocking: ttys%d, count = %d\n",
		       info->line, state->count);
#endif
		schedule();
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&info->open_wait, &wait);
	if (extra_count)
		state->count++;
	info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
	printk("block_til_ready after blocking: ttys%d, count = %d\n",
	       info->line, state->count);
#endif
	if (retval)
		return retval;
	info->flags |= ASYNC_NORMAL_ACTIVE;
	return 0;
}
 
static int get_async_struct(int line, struct async_struct **ret_info)
{
	struct async_struct *info;
	struct serial_state *sstate;
 
	sstate = rs_table + line;
	sstate->count++;
	if (sstate->info) {
		*ret_info = sstate->info;
		return 0;
	}
	info = kmalloc(sizeof(struct async_struct), GFP_KERNEL);
	if (!info) {
		sstate->count--;
		return -ENOMEM;
	}
	memset(info, 0, sizeof(struct async_struct));
	init_waitqueue_head(&info->open_wait);
	init_waitqueue_head(&info->close_wait);
	init_waitqueue_head(&info->delta_msr_wait);
	info->magic = SERIAL_MAGIC;
	info->port = sstate->port;
	info->flags = sstate->flags;
	info->io_type = sstate->io_type;
	info->iomem_base = sstate->iomem_base;
	info->iomem_reg_shift = sstate->iomem_reg_shift;
	info->xmit_fifo_size = sstate->xmit_fifo_size;
	info->line = line;
	info->tqueue.routine = do_softint;
	info->tqueue.data = info;
	info->state = sstate;
	if (sstate->info) {
		kfree(info);
		*ret_info = sstate->info;
		return 0;
	}
	*ret_info = sstate->info = info;
	return 0;
}
 
/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port, linking in its async structure into
 * the IRQ chain.   It also performs the serial-specific
 * initialization for the tty structure.
 */
static int rs_open(struct tty_struct *tty, struct file * filp)
{
	struct async_struct	*info;
	int 			retval, line;
	unsigned long		page;
 
	MOD_INC_USE_COUNT;
	line = MINOR(tty->device) - tty->driver.minor_start;
	if ((line < 0) || (line >= NR_PORTS)) {
		MOD_DEC_USE_COUNT;
		return -ENODEV;
	}
	retval = get_async_struct(line, &info);
	if (retval) {
		MOD_DEC_USE_COUNT;
		return retval;
	}
	tty->driver_data = info;
	info->tty = tty;
	if (serial_paranoia_check(info, tty->device, "rs_open")) {
		MOD_DEC_USE_COUNT;
		return -ENODEV;
	}
 
#ifdef SERIAL_DEBUG_OPEN
	printk("rs_open %s%d, count = %d\n", tty->driver.name, info->line,
	       info->state->count);
#endif
	info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 
	if (!tmp_buf) {
		page = get_zeroed_page(GFP_KERNEL);
		if (!page) {
			MOD_DEC_USE_COUNT;
			return -ENOMEM;
		}
		if (tmp_buf)
			free_page(page);
		else
			tmp_buf = (unsigned char *) page;
	}
 
	/*
	 * If the port is the middle of closing, bail out now
	 */
	if (tty_hung_up_p(filp) ||
	    (info->flags & ASYNC_CLOSING)) {
		if (info->flags & ASYNC_CLOSING)
			interruptible_sleep_on(&info->close_wait);
		MOD_DEC_USE_COUNT;
#ifdef SERIAL_DO_RESTART
		return ((info->flags & ASYNC_HUP_NOTIFY) ?
			-EAGAIN : -ERESTARTSYS);
#else
		return -EAGAIN;
#endif
	}
 
	/*
	 * Start up serial port
	 */
	retval = startup(info);
	if (retval) {
		MOD_DEC_USE_COUNT;
		return retval;
	}
 
	retval = block_til_ready(tty, filp, info);
	if (retval) {
#ifdef SERIAL_DEBUG_OPEN
		printk("rs_open returning after block_til_ready with %d\n",
		       retval);
#endif
		MOD_DEC_USE_COUNT;
		return retval;
	}
 
	if ((info->state->count == 1) &&
	    (info->flags & ASYNC_SPLIT_TERMIOS)) {
		if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
			*tty->termios = info->state->normal_termios;
		else
			*tty->termios = info->state->callout_termios;
		change_speed(info, 0);
	}
#ifdef CONFIG_AU1X00_SERIAL_CONSOLE
	if (sercons.cflag && sercons.index == line) {
		tty->termios->c_cflag = sercons.cflag;
		sercons.cflag = 0;
		change_speed(info, 0);
	}
#endif
	info->session = current->session;
	info->pgrp = current->pgrp;
 
#ifdef SERIAL_DEBUG_OPEN
	printk("rs_open ttys%d successful...", info->line);
#endif
	return 0;
}
 
/*
 * /proc fs routines....
 */
 
static inline int line_info(char *buf, struct serial_state *state)
{
	struct async_struct *info = state->info, scr_info;
	char	stat_buf[30], control, status;
	int	ret;
	unsigned long flags;
 
	ret = sprintf(buf, "%d: uart:%s port:%lX irq:%d",
		      state->line, uart_config[state->type].name,
		      state->port, state->irq);
 
	if (!state->port || (state->type == PORT_UNKNOWN)) {
		ret += sprintf(buf+ret, "\n");
		return ret;
	}
 
	/*
	 * Figure out the current RS-232 lines
	 */
	if (!info) {
		info = &scr_info;	/* This is just for serial_{in,out} */
 
		info->magic = SERIAL_MAGIC;
		info->port = state->port;
		info->flags = state->flags;
		info->quot = 0;
		info->tty = 0;
	}
	spin_lock_irqsave(&serial_lock, flags);
	status = serial_in(info, UART_MSR);
	control = info != &scr_info ? info->MCR : serial_in(info, UART_MCR);
	spin_unlock_irqrestore(&serial_lock, flags);
 
	stat_buf[0] = 0;
	stat_buf[1] = 0;
	if (control & UART_MCR_RTS)
		strcat(stat_buf, "|RTS");
	if (status & UART_MSR_CTS)
		strcat(stat_buf, "|CTS");
	if (control & UART_MCR_DTR)
		strcat(stat_buf, "|DTR");
	if (status & UART_MSR_DSR)
		strcat(stat_buf, "|DSR");
	if (status & UART_MSR_DCD)
		strcat(stat_buf, "|CD");
	if (status & UART_MSR_RI)
		strcat(stat_buf, "|RI");
 
	if (info->quot) {
		ret += sprintf(buf+ret, " baud:%d",
			       state->baud_base / info->quot);
	}
 
	ret += sprintf(buf+ret, " tx:%d rx:%d",
		      state->icount.tx, state->icount.rx);
 
	if (state->icount.frame)
		ret += sprintf(buf+ret, " fe:%d", state->icount.frame);
 
	if (state->icount.parity)
		ret += sprintf(buf+ret, " pe:%d", state->icount.parity);
 
	if (state->icount.brk)
		ret += sprintf(buf+ret, " brk:%d", state->icount.brk);
 
	if (state->icount.overrun)
		ret += sprintf(buf+ret, " oe:%d", state->icount.overrun);
 
	/*
	 * Last thing is the RS-232 status lines
	 */
	ret += sprintf(buf+ret, " %s\n", stat_buf+1);
	return ret;
}
 
int rs_read_proc(char *page, char **start, off_t off, int count,
		 int *eof, void *data)
{
	int i, len = 0, l;
	off_t	begin = 0;
 
	len += sprintf(page, "serinfo:1.0 driver:%s%s revision:%s\n",
		       serial_version, LOCAL_VERSTRING, serial_revdate);
	for (i = 0; i < NR_PORTS && len < 4000; i++) {
		l = line_info(page + len, &rs_table[i]);
		len += l;
		if (len+begin > off+count)
			goto done;
		if (len+begin < off) {
			begin += len;
			len = 0;
		}
	}
	*eof = 1;
done:
	if (off >= len+begin)
		return 0;
	*start = page + (off-begin);
	return ((count < begin+len-off) ? count : begin+len-off);
}
 
/*
 * ---------------------------------------------------------------------
 * rs_init() and friends
 *
 * rs_init() is called at boot-time to initialize the serial driver.
 * ---------------------------------------------------------------------
 */
 
/*
 * This routine prints out the appropriate serial driver version
 * number, and identifies which options were configured into this
 * driver.
 */
static char serial_options[] __initdata =
       " no serial options enabled\n";
#undef SERIAL_OPT
 
static _INLINE_ void show_serial_version(void)
{
 	printk(KERN_INFO "%s version %s%s (%s) with%s", serial_name,
	       serial_version, LOCAL_VERSTRING, serial_revdate,
	       serial_options);
}
 
 
/*
 * This routine is called by rs_init() to initialize a specific serial
 * port.  It determines what type of UART chip this serial port is
 * using: 8250, 16450, 16550, 16550A.  The important question is
 * whether or not this UART is a 16550A or not, since this will
 * determine whether or not we can use its FIFO features or not.
 */
static void autoconfig(struct serial_state * state)
{
	struct async_struct *info, scr_info;
	unsigned long flags;
 
 
#ifdef SERIAL_DEBUG_AUTOCONF
	printk("Testing ttyS%d (0x%04lx, 0x%04x)...\n", state->line,
	       state->port, (unsigned) state->iomem_base);
#endif
 
	if (!CONFIGURED_SERIAL_PORT(state))
		return;
 
	if (au_readl(UART_MOD_CNTRL + state->port) != 0x3) {
		au_writel(3, UART_MOD_CNTRL + state->port);
		au_sync_delay(10);
	}
 
	state->type = PORT_16550;
	info = &scr_info;	/* This is just for serial_{in,out} */
 
	info->magic = SERIAL_MAGIC;
	info->state = state;
	info->port = state->port;
	info->flags = state->flags;
	info->io_type = state->io_type;
	info->iomem_base = state->iomem_base;
	info->iomem_reg_shift = state->iomem_reg_shift;
 
 
	spin_lock_irqsave(&serial_lock, flags);
	state->xmit_fifo_size =	uart_config[state->type].dfl_xmit_fifo_size;
 
	if (info->port) {
			request_region(info->port,8,"serial(auto)");
	}
 
	/*
	 * Reset the UART.
	 */
	serial_outp(info, UART_FCR, (UART_FCR_ENABLE_FIFO |
				     UART_FCR_CLEAR_RCVR |
				     UART_FCR_CLEAR_XMIT));
	serial_outp(info, UART_FCR, 0);
	(void)serial_in(info, UART_RX);
	serial_outp(info, UART_IER, 0);
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
int register_serial(struct serial_struct *req);
void unregister_serial(int line);
 
/*
 * The serial driver boot-time initialization code!
 */
static int __init rs_init(void)
{
	int i;
	struct serial_state * state;
 
	init_bh(SERIAL_BH, do_serial_bh);
	init_timer(&serial_timer);
	serial_timer.function = rs_timer;
	mod_timer(&serial_timer, jiffies + RS_STROBE_TIME);
 
	for (i = 0; i < NR_IRQS; i++) {
		IRQ_ports[i] = 0;
		IRQ_timeout[i] = 0;
	}
#ifdef CONFIG_AU1X00_SERIAL_CONSOLE
	/*
	 *	The interrupt of the serial console port
	 *	can't be shared.
	 */
	if (sercons.flags & CON_CONSDEV) {
		for(i = 0; i < NR_PORTS; i++)
			if (i != sercons.index &&
			    rs_table[i].irq == rs_table[sercons.index].irq)
				rs_table[i].irq = 0;
	}
#endif
	show_serial_version();
 
	/* Initialize the tty_driver structure */
 
	memset(&serial_driver, 0, sizeof(struct tty_driver));
	serial_driver.magic = TTY_DRIVER_MAGIC;
	serial_driver.driver_name = "serial";
#if (LINUX_VERSION_CODE > 0x2032D && defined(CONFIG_DEVFS_FS))
	serial_driver.name = "tts/%d";
#else
	serial_driver.name = "ttyS";
#endif
	serial_driver.major = TTY_MAJOR;
	serial_driver.minor_start = 64 + SERIAL_DEV_OFFSET;
	serial_driver.num = NR_PORTS;
	serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
	serial_driver.subtype = SERIAL_TYPE_NORMAL;
	serial_driver.init_termios = tty_std_termios;
	serial_driver.init_termios.c_cflag =
		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
	serial_driver.flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS;
	serial_driver.refcount = &serial_refcount;
	serial_driver.table = serial_table;
	serial_driver.termios = serial_termios;
	serial_driver.termios_locked = serial_termios_locked;
 
	serial_driver.open = rs_open;
	serial_driver.close = rs_close;
	serial_driver.write = rs_write;
	serial_driver.put_char = rs_put_char;
	serial_driver.flush_chars = rs_flush_chars;
	serial_driver.write_room = rs_write_room;
	serial_driver.chars_in_buffer = rs_chars_in_buffer;
	serial_driver.flush_buffer = rs_flush_buffer;
	serial_driver.ioctl = rs_ioctl;
	serial_driver.throttle = rs_throttle;
	serial_driver.unthrottle = rs_unthrottle;
	serial_driver.set_termios = rs_set_termios;
	serial_driver.stop = rs_stop;
	serial_driver.start = rs_start;
	serial_driver.hangup = rs_hangup;
	serial_driver.break_ctl = rs_break;
	serial_driver.send_xchar = rs_send_xchar;
	serial_driver.wait_until_sent = rs_wait_until_sent;
	serial_driver.read_proc = rs_read_proc;
 
	/*
	 * The callout device is just like normal device except for
	 * major number and the subtype code.
	 */
	callout_driver = serial_driver;
#if (LINUX_VERSION_CODE > 0x2032D && defined(CONFIG_DEVFS_FS))
	callout_driver.name = "cua/%d";
#else
	callout_driver.name = "cua";
#endif
	callout_driver.major = TTYAUX_MAJOR;
	callout_driver.subtype = SERIAL_TYPE_CALLOUT;
	callout_driver.read_proc = 0;
	callout_driver.proc_entry = 0;
 
	if (tty_register_driver(&serial_driver))
		panic("Couldn't register serial driver");
	if (tty_register_driver(&callout_driver))
		panic("Couldn't register callout driver");
 
	for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
		state->baud_base = get_au1x00_uart_baud_base();
		state->magic = SSTATE_MAGIC;
		state->line = i;
		state->type = PORT_UNKNOWN;
		state->custom_divisor = 0;
		state->close_delay = 5*HZ/10;
		state->closing_wait = 30*HZ;
		state->callout_termios = callout_driver.init_termios;
		state->normal_termios = serial_driver.init_termios;
		state->icount.cts = state->icount.dsr =
			state->icount.rng = state->icount.dcd = 0;
		state->icount.rx = state->icount.tx = 0;
		state->icount.frame = state->icount.parity = 0;
		state->icount.overrun = state->icount.brk = 0;
		state->irq = irq_cannonicalize(state->irq);
		if (state->hub6)
			state->io_type = SERIAL_IO_HUB6;
		if (state->port && check_region(state->port,8)) {
			continue;
		}
 
		if (state->flags & ASYNC_BOOT_AUTOCONF) {
			autoconfig(state);
		}
	}
	for (i = 0, state = rs_table; i < NR_PORTS; i++,state++) {
		if (state->type == PORT_UNKNOWN) {
			continue;
		}
		printk(KERN_INFO "ttyS%02d%s at 0x%04lx (irq = %d) is a %s\n",
		       state->line + SERIAL_DEV_OFFSET,
		       (state->flags & ASYNC_FOURPORT) ? " FourPort" : "",
		       state->port, state->irq,
		       uart_config[state->type].name);
		tty_register_devfs(&serial_driver, 0,
				   serial_driver.minor_start + state->line);
		tty_register_devfs(&callout_driver, 0,
				   callout_driver.minor_start + state->line);
	}
	return 0;
}
 
/*
 * register_serial and unregister_serial allows for 16x50 serial ports to be
 * configured at run-time, to support PCMCIA modems.
 */
 
/**
 *	register_serial - configure a 16x50 serial port at runtime
 *	@req: request structure
 *
 *	Configure the serial port specified by the request. If the
 *	port exists and is in use an error is returned. If the port
 *	is not currently in the table it is added.
 *
 *	The port is then probed and if neccessary the IRQ is autodetected
 *	If this fails an error is returned.
 *
 *	On success the port is ready to use and the line number is returned.
 */
 
int register_serial(struct serial_struct *req)
{
	int i;
	unsigned long flags;
	struct serial_state *state;
	struct async_struct *info;
	unsigned long port;
 
	port = req->port;
	if (HIGH_BITS_OFFSET)
		port += (unsigned long) req->port_high << HIGH_BITS_OFFSET;
 
	spin_lock_irqsave(&serial_lock, flags);
	for (i = 0; i < NR_PORTS; i++) {
		if ((rs_table[i].port == port) &&
		    (rs_table[i].iomem_base == req->iomem_base))
			break;
	}
	if (i == NR_PORTS) {
		for (i = 0; i < NR_PORTS; i++)
			if ((rs_table[i].type == PORT_UNKNOWN) &&
			    (rs_table[i].count == 0))
				break;
	}
	if (i == NR_PORTS) {
		spin_unlock_irqrestore(&serial_lock, flags);
		return -1;
	}
	state = &rs_table[i];
	if (rs_table[i].count) {
		spin_unlock_irqrestore(&serial_lock, flags);
		printk("Couldn't configure serial #%d (port=%ld,irq=%d): "
		       "device already open\n", i, port, req->irq);
		return -1;
	}
	state->irq = req->irq;
	state->port = port;
	state->flags = req->flags;
	state->io_type = req->io_type;
	state->iomem_base = req->iomem_base;
	state->iomem_reg_shift = req->iomem_reg_shift;
	if (req->baud_base)
		state->baud_base = req->baud_base;
	if ((info = state->info) != NULL) {
		info->port = port;
		info->flags = req->flags;
		info->io_type = req->io_type;
		info->iomem_base = req->iomem_base;
		info->iomem_reg_shift = req->iomem_reg_shift;
	}
	autoconfig(state);
	if (state->type == PORT_UNKNOWN) {
		spin_unlock_irqrestore(&serial_lock, flags);
		printk("register_serial(): autoconfig failed\n");
		return -1;
	}
	spin_unlock_irqrestore(&serial_lock, flags);
 
       printk(KERN_INFO "ttyS%02d at %s 0x%04lx (irq = %d) is a %s\n",
	      state->line + SERIAL_DEV_OFFSET,
	      state->iomem_base ? "iomem" : "port",
	      state->iomem_base ? (unsigned long)state->iomem_base :
	      state->port, state->irq, uart_config[state->type].name);
	tty_register_devfs(&serial_driver, 0,
			   serial_driver.minor_start + state->line);
	tty_register_devfs(&callout_driver, 0,
			   callout_driver.minor_start + state->line);
	return state->line + SERIAL_DEV_OFFSET;
}
 
/**
 *	unregister_serial - deconfigure a 16x50 serial port
 *	@line: line to deconfigure
 *
 *	The port specified is deconfigured and its resources are freed. Any
 *	user of the port is disconnected as if carrier was dropped. Line is
 *	the port number returned by register_serial().
 */
 
void unregister_serial(int line)
{
	unsigned long flags;
	struct serial_state *state = &rs_table[line];
 
	spin_lock_irqsave(&serial_lock, flags);
	if (state->info && state->info->tty)
		tty_hangup(state->info->tty);
	state->type = PORT_UNKNOWN;
	printk(KERN_INFO "tty%02d unloaded\n", state->line);
	/* These will be hidden, because they are devices that will no longer
	 * be available to the system. (ie, PCMCIA modems, once ejected)
	 */
	tty_unregister_devfs(&serial_driver,
			     serial_driver.minor_start + state->line);
	tty_unregister_devfs(&callout_driver,
			     callout_driver.minor_start + state->line);
	spin_unlock_irqrestore(&serial_lock, flags);
}
 
static void __exit rs_fini(void)
{
	unsigned long flags;
	int e1, e2;
	int i;
	struct async_struct *info;
 
	/* printk("Unloading %s: version %s\n", serial_name, serial_version); */
	del_timer_sync(&serial_timer);
	spin_lock_irqsave(&serial_lock, flags);
        remove_bh(SERIAL_BH);
	if ((e1 = tty_unregister_driver(&serial_driver)))
		printk("serial: failed to unregister serial driver (%d)\n",
		       e1);
	if ((e2 = tty_unregister_driver(&callout_driver)))
		printk("serial: failed to unregister callout driver (%d)\n",
		       e2);
	spin_unlock_irqrestore(&serial_lock, flags);
 
	for (i = 0; i < NR_PORTS; i++) {
		if ((info = rs_table[i].info)) {
			rs_table[i].info = NULL;
			kfree(info);
		}
		if ((rs_table[i].type != PORT_UNKNOWN) && rs_table[i].port) {
				release_region(rs_table[i].port, 8);
		}
	}
	if (tmp_buf) {
		unsigned long pg = (unsigned long) tmp_buf;
		tmp_buf = NULL;
		free_page(pg);
	}
}
 
module_init(rs_init);
module_exit(rs_fini);
MODULE_DESCRIPTION("Au1x00 serial driver");
 
 
/*
 * ------------------------------------------------------------
 * Serial console driver
 * ------------------------------------------------------------
 */
#ifdef CONFIG_AU1X00_SERIAL_CONSOLE
 
#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
 
static struct async_struct async_sercons;
 
/*
 *	Wait for transmitter & holding register to empty
 */
static inline void wait_for_xmitr(struct async_struct *info)
{
	unsigned int status, tmout = 0xffffff;
 
	do {
		status = serial_in(info, UART_LSR);
 
		if (status & UART_LSR_BI)
			lsr_break_flag = UART_LSR_BI;
 
		if (--tmout == 0)
			break;
	} while((status & BOTH_EMPTY) != BOTH_EMPTY);
}
 
 
/*
 *	Print a string to the serial port trying not to disturb
 *	any possible real use of the port...
 *
 *	The console_lock must be held when we get here.
 */
static void serial_console_write(struct console *co, const char *s,
				unsigned count)
{
	static struct async_struct *info = &async_sercons;
	int ier;
	unsigned i;
 
	/*
	 *	First save the IER then disable the interrupts
	 */
	ier = serial_in(info, UART_IER);
	serial_out(info, UART_IER, 0x00);
 
	/*
	 *	Now, do each character
	 */
	for (i = 0; i < count; i++, s++) {
		wait_for_xmitr(info);
 
		/*
		 *	Send the character out.
		 *	If a LF, also do CR...
		 */
		serial_out(info, UART_TX, *s);
		if (*s == 10) {
			wait_for_xmitr(info);
			serial_out(info, UART_TX, 13);
		}
	}
 
	/*
	 *	Finally, Wait for transmitter & holding register to empty
	 * 	and restore the IER
	 */
	wait_for_xmitr(info);
	serial_out(info, UART_IER, ier);
}
 
/*
 *	Receive character from the serial port
 */
static int serial_console_wait_key(struct console *co)
{
	static struct async_struct *info;
	int ier, c;
 
	info = &async_sercons;
 
	/*
	 *	First save the IER then disable the interrupts so
	 *	that the real driver for the port does not get the
	 *	character.
	 */
	ier = serial_in(info, UART_IER);
	serial_out(info, UART_IER, 0x00);
 
	while ((serial_in(info, UART_LSR) & UART_LSR_DR) == 0);
	c = serial_in(info, UART_RX);
 
	/*
	 *	Restore the interrupts
	 */
	serial_out(info, UART_IER, ier);
 
	return c;
}
 
static kdev_t serial_console_device(struct console *c)
{
	return MKDEV(TTY_MAJOR, 64 + c->index);
}
 
/*
 *	Setup initial baud/bits/parity. We do two things here:
 *	- construct a cflag setting for the first rs_open()
 *	- initialize the serial port
 *	Return non-zero if we didn't find a serial port.
 */
static int __init serial_console_setup(struct console *co, char *options)
{
	static struct async_struct *info;
	struct serial_state *state;
	unsigned cval;
	int	baud = 9600;
	int	bits = 8;
	int	parity = 'n';
	int	cflag = CREAD | HUPCL | CLOCAL;
	int	quot = 0;
	char	*s;
 
	if (options) {
		baud = simple_strtoul(options, NULL, 10);
		s = options;
		while(*s >= '0' && *s <= '9')
			s++;
		if (*s) parity = *s++;
		if (*s) bits   = *s - '0';
	}
 
	/*
	 *	Now construct a cflag setting.
	 */
	switch(baud) {
		case 1200:
			cflag |= B1200;
			break;
		case 2400:
			cflag |= B2400;
			break;
		case 4800:
			cflag |= B4800;
			break;
		case 19200:
			cflag |= B19200;
			break;
		case 38400:
			cflag |= B38400;
			break;
		case 57600:
			cflag |= B57600;
			break;
		case 115200:
			cflag |= B115200;
			break;
		case 9600:
		default:
			cflag |= B9600;
			break;
	}
	switch(bits) {
		case 7:
			cflag |= CS7;
			break;
		default:
		case 8:
			cflag |= CS8;
			break;
	}
	switch(parity) {
		case 'o': case 'O':
			cflag |= PARODD;
			break;
		case 'e': case 'E':
			cflag |= PARENB;
			break;
	}
	co->cflag = cflag;
 
	/*
	 *	Divisor, bytesize and parity
	 */
	state = rs_table + co->index;
	info = &async_sercons;
	info->magic = SERIAL_MAGIC;
	info->state = state;
	info->port = state->port;
	info->flags = state->flags;
	info->io_type = state->io_type;
	info->iomem_base = state->iomem_base;
	info->iomem_reg_shift = state->iomem_reg_shift;
	state->baud_base = get_au1x00_uart_baud_base();
	quot = state->baud_base / baud;
 
	cval = cflag & (CSIZE | CSTOPB);
	cval >>= 4;
	if (cflag & PARENB)
		cval |= UART_LCR_PARITY;
	if (!(cflag & PARODD))
		cval |= UART_LCR_EPAR;
 
	/*
	 *	Disable UART interrupts, set DTR and RTS high
	 *	and set speed.
	 */
	serial_out(info, UART_CLK, quot & 0xffff);
	serial_out(info, UART_IER, 0);
	serial_out(info, UART_MCR, UART_MCR_DTR | UART_MCR_RTS);
 
	/*
	 *	If we read 0xff from the LSR, there is no UART here.
	 */
	if (serial_in(info, UART_LSR) == 0xff)
		return -1;
 
	return 0;
}
 
static struct console sercons = {
	.name		= "ttyS",
	.write		= serial_console_write,
	.device		= serial_console_device,
	.setup		= serial_console_setup,
	.flags		= CON_PRINTBUFFER,
	.index		= -1,
};
 
/*
 *	Register console.
 */
void __init au1x00_serial_console_init(void)
{
	register_console(&sercons);
}
#endif
 
/*
  Local variables:
  compile-command: "gcc -D__KERNEL__ -I../../include -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -fno-strict-aliasing -pipe -fno-strength-reduce -march=i586 -DMODULE -DMODVERSIONS -include ../../include/linux/modversions.h   -DEXPORT_SYMTAB -c serial.c"
  End:
*/
 

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