Import 2.1.15

[davej-history.git] / drivers / char / esp.c

/*
 * esp.c - driver for Hayes ESP serial cards
 *
 * --- Notices from serial.c, upon which this driver is based ---
 *
 * Copyright (C) 1991, 1992 Linus Torvalds
 *
 * Extensively rewritten by Theodore Ts'o, 8/16/92 -- 9/14/92. Now
 * much more extensible to support other serial cards based on the
 * 16450/16550A UART's. Added support for the AST FourPort and the
 * Accent Async board. 
 *
 * set_serial_info fixed to set the flags, custom divisor, and uart
 * type fields. Fix suggested by Michael K. Johnson 12/12/92.
 *
 * 11/95: TIOCMIWAIT, TIOCGICOUNT by Angelo Haritsis <ah@doc.ic.ac.uk>
 *
 * 03/96: Modularised by Angelo Haritsis <ah@doc.ic.ac.uk>
 *
 * rs_set_termios fixed to look also for changes of the input
 * flags INPCK, BRKINT, PARMRK, IGNPAR and IGNBRK.
 * Bernd Anhäupl 05/17/96.
 *
 * --- End of notices from serial.c ---
 *
 * Support for the ESP serial card by Andrew J. Robinson
 * <arobinso@nyx.net> (Card detection routine taken from a patch
 * by Dennis J. Boylan). Patches to allow use with 2.1.x contributed
 * by Chris Faylor.
 *
 * This module exports the following rs232 io functions:
 *
 * int esp_init(void);
 */

#include <linux/module.h>
#include <linux/errno.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/serial_reg.h>
#include <linux/config.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 <asm/system.h>
#include <asm/io.h>
#include <asm/segment.h>
#include <asm/bitops.h>

#include <asm/dma.h>
#include <linux/malloc.h>
#include <asm/uaccess.h>

#include"esp.h"

#define NR_PORTS 64/* maximum number of ports */
#define NR_PRIMARY 8/* maximum number of primary ports */

/* The following variables can be set by giving module options */
static int irq[NR_PRIMARY] = {0,0,0,0,0,0,0,0};/* IRQ for each base port */
static unsigned int divisor[NR_PRIMARY] = {0,0,0,0,0,0,0,0};
/* custom divisor for each port */
static unsigned int dma = CONFIG_ESP_DMA_CHANNEL;/* DMA channel */
static unsigned int trigger = CONFIG_ESP_TRIGGER_LEVEL;/* FIFO trigger level */
/* END */

static char*dma_buffer;

#define DMA_BUFFER_SZ 1024

#define WAKEUP_CHARS 1024

static char*serial_name ="ESP driver";
static char*serial_version ="1.0";

DECLARE_TASK_QUEUE(tq_esp);

static struct tty_driver esp_driver, esp_callout_driver;
static int serial_refcount;

/* serial subtype definitions */
#define SERIAL_TYPE_NORMAL 1
#define SERIAL_TYPE_CALLOUT 2

/*
 * Serial driver configuration section. Here are the various options:
 *
 * SERIAL_PARANOIA_CHECK
 * Check the magic number for the esp_structure where
 * ever possible.
 */

#undef SERIAL_PARANOIA_CHECK
#define SERIAL_DO_RESTART

#undef SERIAL_DEBUG_INTR
#undef SERIAL_DEBUG_OPEN
#undef SERIAL_DEBUG_FLOW

#define _INLINE_ inline

#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

static struct esp_struct *IRQ_ports[16];

static voidautoconfig(struct esp_struct * info);
static voidchange_speed(struct esp_struct *info);

/*
 * This assumes you have a 1.8432 MHz clock for your UART.
 *
 * It'd be nice if someone built a serial card with a 24.576 MHz
 * clock, since the 16550A is capable of handling a top speed of 1.5
 * megabits/second; but this requires the faster clock.
 */
#define BASE_BAUD ((1843200 / 16) * (1 << ESPC_SCALE))

/* Standard COM flags (except for COM4, because of the 8514 problem) */
#define STD_COM_FLAGS (ASYNC_BOOT_AUTOCONF | ASYNC_SKIP_TEST)

static struct tty_struct *serial_table[NR_PORTS];
static struct termios *serial_termios[NR_PORTS];
static struct termios *serial_termios_locked[NR_PORTS];

#ifndef MIN
#define MIN(a,b) ((a) < (b) ? (a) : (b))
#endif

/*
 * tmp_buf is used as a temporary buffer by serial_write. We need to
 * lock it in case the memcpy_fromfs 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 =0;
static struct semaphore tmp_buf_sem = MUTEX;

staticinlineintserial_paranoia_check(struct esp_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 esp_struct for (%s) in %s\n";

if(!info) {
printk(badinfo,kdevname(device), routine);
return1;
}
if(info->magic != ESP_MAGIC) {
printk(badmagic,kdevname(device), routine);
return1;
}
#endif
return0;
}

/*
 * This is used to figure out the divisor speeds and the timeouts
 */
static int baud_table[] = {
0,50,75,110,134,150,200,300,600,1200,1800,2400,4800,
9600,19200,38400,57600,115200,230400,460800,0};

staticinlineunsigned intserial_in(struct esp_struct *info,int offset)
{
returninb(info->port + offset);
}

staticinlinevoidserial_out(struct esp_struct *info,int offset,int value)
{
outb(value, info->port+offset);
}

staticinlineint__get_order(unsigned long size)
{
int order;

 size = (size + PAGE_SIZE -1) >> PAGE_SHIFT;
 order = -1;
do{
 size >>=1;
 order++;
}while(size);

return order;
}

/*
 * ------------------------------------------------------------
 * rs_stop() and rs_start()
 *
 * This routines are called before setting or resetting tty->stopped.
 * They enable or disable transmitter interrupts, as necessary.
 * ------------------------------------------------------------
 */
static voidrs_stop(struct tty_struct *tty)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;
unsigned long flags;

if(serial_paranoia_check(info, tty->device,"rs_stop"))
return;

save_flags(flags);cli();
if(info->IER & UART_IER_THRI) {
 info->IER &= ~UART_IER_THRI;
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);
}

restore_flags(flags);
}

static voidrs_start(struct tty_struct *tty)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;
unsigned long flags;

if(serial_paranoia_check(info, tty->device,"rs_start"))
return;

save_flags(flags);cli();
if(info->xmit_cnt && info->xmit_buf && !(info->IER & UART_IER_THRI)) {
 info->IER |= UART_IER_THRI;
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);
}
restore_flags(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_ voidrs_sched_event(struct esp_struct *info,
int event)
{
 info->event |=1<< event;
queue_task_irq_off(&info->tqueue, &tq_esp);
mark_bh(ESP_BH);
}

static _INLINE_ voidreceive_chars_dma(struct esp_struct *info,int*dma_bytes,
int*dma_direction,unsigned int*who_dma)
{
unsigned int num_chars;

if(*dma_bytes) {
 info->stat_flags |= STAT_NEED_DMA;
return;
}

 info->stat_flags &= ~(STAT_RX_TIMEOUT | STAT_NEED_DMA);

serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
serial_out(info, UART_ESI_CMD1, ESI_GET_RX_AVAIL);
 num_chars =serial_in(info, UART_ESI_STAT1) <<8;
 num_chars |=serial_in(info, UART_ESI_STAT2);

if(!num_chars)
return;

*dma_bytes = num_chars;
*dma_direction = DMA_MODE_READ;
*who_dma = info->port;
disable_dma(dma);
clear_dma_ff(dma);
set_dma_mode(dma, DMA_MODE_READ);
set_dma_addr(dma,virt_to_bus(dma_buffer));
set_dma_count(dma, num_chars);
enable_dma(dma);
serial_out(info, UART_ESI_CMD1, ESI_START_DMA_RX);
}

static voiddo_ttybuf(void*private_)
{
struct esp_struct *info = (struct esp_struct *) private_;
struct tty_struct *tty;
int avail_bytes, x_bytes;
unsigned long int flags;

save_flags(flags);cli();
 tty = info->tty;

if(!tty) {
restore_flags(flags);
return;
}

 avail_bytes = TTY_FLIPBUF_SIZE - tty->flip.count;

if(avail_bytes) {
if(info->tty_buf->count < avail_bytes)
 x_bytes = info->tty_buf->count;
else
 x_bytes = avail_bytes;

 tty->flip.count += x_bytes;
memcpy(tty->flip.char_buf_ptr, info->tty_buf->char_buf,
 x_bytes);
memcpy(tty->flip.flag_buf_ptr, info->tty_buf->flag_buf,
 x_bytes);
 tty->flip.char_buf_ptr += x_bytes;
 tty->flip.flag_buf_ptr += x_bytes;
 info->tty_buf->count -= x_bytes;
 info->tty_buf->char_buf_ptr -= x_bytes;
 info->tty_buf->flag_buf_ptr -= x_bytes;

if(info->tty_buf->count) {
memmove(info->tty_buf->char_buf,
 info->tty_buf->char_buf + x_bytes,
 info->tty_buf->count);
queue_task_irq_off(&info->tty_buf->tqueue,
&tq_timer);
}

queue_task_irq_off(&tty->flip.tqueue, &tq_timer);
}else{
queue_task_irq_off(&info->tty_buf->tqueue, &tq_timer);
}

restore_flags(flags);
}

static _INLINE_ voidreceive_chars_dma_done(struct esp_struct *info,
int*dma_bytes,int*dma_direction,unsigned int*who_dma,int status)
{
struct tty_struct *tty = info->tty;
int num_bytes, bytes_left, x_bytes;
struct tty_flip_buffer *buffer;

if(!(*dma_bytes) || (*who_dma != info->port))
return;

disable_dma(dma);
clear_dma_ff(dma);

 num_bytes = *dma_bytes -get_dma_residue(dma);

 buffer = &(tty->flip);
 bytes_left = num_bytes;

if(info->tty_buf->count && (tty->flip.count < TTY_FLIPBUF_SIZE))
do_ttybuf(info);

while(bytes_left >0) {
if((buffer->count + bytes_left) > TTY_FLIPBUF_SIZE)
 x_bytes = TTY_FLIPBUF_SIZE - buffer->count;
else
 x_bytes = bytes_left;

memcpy(buffer->char_buf_ptr,
 dma_buffer + (num_bytes - bytes_left), x_bytes);
 buffer->char_buf_ptr += x_bytes;
 buffer->count += x_bytes;
memset(buffer->flag_buf_ptr,0, x_bytes);
 buffer->flag_buf_ptr += x_bytes;
 bytes_left -= x_bytes;

if(bytes_left >0) {
if(buffer == info->tty_buf)
break;
else
 buffer = info->tty_buf;
}
}

if(num_bytes >0) {
 buffer->flag_buf_ptr--;

 status >>=8;
 status &= (0x1c& info->read_status_mask);

if(status & info->ignore_status_mask) {
 buffer->count--;
 buffer->char_buf_ptr--;
 buffer->flag_buf_ptr--;
}else if(status &0x10) {
*buffer->flag_buf_ptr = TTY_BREAK;
if(info->flags & ASYNC_SAK)
do_SAK(tty);
}else if(status &0x08)
*buffer->flag_buf_ptr = TTY_FRAME;
else if(status &0x04)
*buffer->flag_buf_ptr = TTY_PARITY;

 buffer->flag_buf_ptr++;

if(buffer == info->tty_buf)
queue_task_irq_off(&info->tty_buf->tqueue, &tq_timer);

queue_task_irq_off(&tty->flip.tqueue, &tq_timer);
}

if(*dma_bytes != num_bytes) {
*dma_bytes =0;
receive_chars_dma(info, dma_bytes, dma_direction, who_dma);
}else
*dma_bytes =0;
}

static _INLINE_ voidtransmit_chars_dma(struct esp_struct *info,int*dma_bytes,
int*dma_direction,unsigned int*who_dma)
{
int count;

if(*dma_bytes) {
 info->stat_flags |= STAT_NEED_DMA;
return;
}

 info->stat_flags &= ~STAT_NEED_DMA;

if((info->xmit_cnt <=0) || info->tty->stopped ||
 info->tty->hw_stopped) {
 info->IER &= ~UART_IER_THRI;
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);
return;
}

serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
 count =serial_in(info, UART_ESI_STAT1) <<8;
 count |=serial_in(info, UART_ESI_STAT2);

if(!count)
return;

 count = ((count < info->xmit_cnt) ? count : info->xmit_cnt);

if(info->xmit_tail + count <= ESP_XMIT_SIZE) {
memcpy(dma_buffer, &(info->xmit_buf[info->xmit_tail]),
 count);
}else{
int i = ESP_XMIT_SIZE - info->xmit_tail;
memcpy(dma_buffer, &(info->xmit_buf[info->xmit_tail]),
 i);
memcpy(&(dma_buffer[i]), info->xmit_buf, count - i);
}

 info->xmit_cnt -= count;
 info->xmit_tail = (info->xmit_tail + count) & (ESP_XMIT_SIZE -1);

if(info->xmit_cnt < WAKEUP_CHARS)
rs_sched_event(info, ESP_EVENT_WRITE_WAKEUP);

#ifdef SERIAL_DEBUG_INTR
printk("THRE...");
#endif

if(info->xmit_cnt <=0) {
 info->IER &= ~UART_IER_THRI;
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);
}

*dma_bytes = count;
*dma_direction = DMA_MODE_WRITE;
*who_dma = info->port;
disable_dma(dma);
clear_dma_ff(dma);
set_dma_mode(dma, DMA_MODE_WRITE);
set_dma_addr(dma,virt_to_bus(dma_buffer));
set_dma_count(dma, count);
enable_dma(dma);
serial_out(info, UART_ESI_CMD1, ESI_START_DMA_TX);
}

static _INLINE_ voidtransmit_chars_dma_done(struct esp_struct *info,
int*dma_bytes,int*dma_direction,unsigned int*who_dma)
{
int num_bytes;

if(!(*dma_bytes) || (*who_dma != info->port))
return;

disable_dma(dma);
clear_dma_ff(dma);

 num_bytes = *dma_bytes -get_dma_residue(dma);

if(*dma_bytes != num_bytes)
{
*dma_bytes -= num_bytes;
memmove(dma_buffer, dma_buffer + num_bytes, *dma_bytes);
*dma_direction = DMA_MODE_WRITE;
disable_dma(dma);
clear_dma_ff(dma);
set_dma_mode(dma, DMA_MODE_WRITE);
set_dma_addr(dma,virt_to_bus(dma_buffer));
set_dma_count(dma, *dma_bytes);
enable_dma(dma);
serial_out(info, UART_ESI_CMD1, ESI_START_DMA_TX);
}else
*dma_bytes =0;
}

static _INLINE_ voidcheck_modem_status(struct esp_struct *info)
{
int status;

serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
 status =serial_in(info, UART_ESI_STAT2);

if(status & UART_MSR_ANY_DELTA) {
/* update input line counters */
if(status & UART_MSR_TERI)
 info->icount.rng++;
if(status & UART_MSR_DDSR)
 info->icount.dsr++;
if(status & UART_MSR_DDCD)
 info->icount.dcd++;
if(status & UART_MSR_DCTS)
 info->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("scheduling hangup...");
#endif
queue_task_irq_off(&info->tqueue_hangup,
&tq_scheduler);
}
}
}

static _INLINE_ voidtx_flowed_on(struct esp_struct *info)
{
#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_ESI_CMD1, ESI_SET_SRV_MASK);/* set mask */
serial_out(info, UART_ESI_CMD2, info->IER);
rs_sched_event(info, ESP_EVENT_WRITE_WAKEUP);
}

static _INLINE_ voidtx_flowed_off(struct esp_struct *info)
{
#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_ESI_CMD1, ESI_SET_SRV_MASK);/* set mask */
serial_out(info, UART_ESI_CMD2, info->IER);
}

/*
 * This is the serial driver's interrupt routine for a single port
 */
static voidrs_interrupt_single(int irq,void*dev_id,struct pt_regs * regs)
{
struct esp_struct * info, *stop_port;
unsigned err_status;
unsigned int scratch;
int pre_bytes;
int check_dma_only =0;
static int dma_bytes;
static int dma_direction;
static int who_dma;

#ifdef SERIAL_DEBUG_INTR
printk("rs_interrupt_single(%d)...", irq);
#endif

/* This routine will currently check ALL ports when an interrupt */
/* is received from ANY port */

 stop_port = info = IRQ_ports[irq];

if(!info)
return;

do{
if(!info->tty || (check_dma_only &&
!(info->stat_flags & STAT_NEED_DMA))) {
 info = info->next_port;
continue;
}

 pre_bytes = dma_bytes;
 err_status =0;
 scratch =serial_in(info, UART_ESI_SID);
if(scratch &0x04) {/* error - check for rx timeout */
serial_out(info, UART_ESI_CMD1, ESI_GET_ERR_STAT);
 err_status =serial_in(info, UART_ESI_STAT1) <<8;
 err_status |=serial_in(info, UART_ESI_STAT2);

if(err_status &0x0100)
 info->stat_flags |= STAT_RX_TIMEOUT;

if(err_status &0x2000)/* UART status */
check_modem_status(info);

if(err_status &0x8000)/* Start break */
wake_up_interruptible(&info->break_wait);

if(err_status &0x0002)/* tx off */
tx_flowed_off(info);

if(err_status &0x0004)/* tx on */
tx_flowed_on(info);
}

if((scratch &0x88) ||/* DMA completed or timed out */
(err_status &0x1c00)/* receive error */)
if(dma_direction == DMA_MODE_READ)
receive_chars_dma_done(info, &dma_bytes,
&dma_direction, &who_dma, err_status);
else
transmit_chars_dma_done(info, &dma_bytes,
&dma_direction, &who_dma);

if(((scratch &0x01) ||
(info->stat_flags & STAT_RX_TIMEOUT)) &&
(info->IER & UART_IER_RDI))
receive_chars_dma(info, &dma_bytes, &dma_direction,
&who_dma);

if((scratch &0x02) && (info->IER & UART_IER_THRI))
transmit_chars_dma(info, &dma_bytes, &dma_direction,
&who_dma);

 info->last_active = jiffies;

if(pre_bytes && !dma_bytes)/* released DMA */
 stop_port = info;

 info = info->next_port;

if((info->irq != irq) || (info == IRQ_ports[irq]))
 check_dma_only =1;

if(check_dma_only && dma_bytes)
 info = stop_port;
}while(info != stop_port);

#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 voiddo_serial_bh(void)
{
run_task_queue(&tq_esp);
}

static voiddo_softint(void*private_)
{
struct esp_struct *info = (struct esp_struct *) private_;
struct tty_struct *tty;

 tty = info->tty;
if(!tty)
return;

if(clear_bit(ESP_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);
}
}

/*
 * This routine is called from the scheduler tqueue when the interrupt
 * routine has signalled that a hangup has occurred. The path of
 * hangup processing is:
 *
 * serial interrupt routine -> (scheduler tqueue) ->
 * do_serial_hangup() -> tty->hangup() -> esp_hangup()
 * 
 */
static voiddo_serial_hangup(void*private_)
{
struct esp_struct *info = (struct esp_struct *) private_;
struct tty_struct *tty;

 tty = info->tty;
if(!tty)
return;

tty_hangup(tty);
}

/*
 * ---------------------------------------------------------------
 * 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.
 * ---------------------------------------------------------------
 */

static voidesp_basic_init(struct esp_struct * info)
{
/* put ESPC in enhanced mode */
serial_out(info, UART_ESI_CMD1, ESI_SET_MODE);
serial_out(info, UART_ESI_CMD2,0x31);

/* disable interrupts for now */
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2,0x00);

/* set interrupt and DMA channel */
serial_out(info, UART_ESI_CMD1, ESI_SET_IRQ);
serial_out(info, UART_ESI_CMD2, (dma <<4) |0x01);
serial_out(info, UART_ESI_CMD1, ESI_SET_ENH_IRQ);
if(info->line %8)/* secondary port */
serial_out(info, UART_ESI_CMD2,0x0d);/* shared */
else if(info->irq ==9)
serial_out(info, UART_ESI_CMD2,0x02);
else
serial_out(info, UART_ESI_CMD2, info->irq);

/* set error status mask (check this) */
serial_out(info, UART_ESI_CMD1, ESI_SET_ERR_MASK);
serial_out(info, UART_ESI_CMD2,0xbd);
serial_out(info, UART_ESI_CMD2,0x06);

/* set DMA timeout */
serial_out(info, UART_ESI_CMD1, ESI_SET_DMA_TMOUT);
serial_out(info, UART_ESI_CMD2,0xff);

/* set FIFO trigger levels */
serial_out(info, UART_ESI_CMD1, ESI_SET_TRIGGER);
serial_out(info, UART_ESI_CMD2, trigger /256);
serial_out(info, UART_ESI_CMD2, trigger %256);
serial_out(info, UART_ESI_CMD2, trigger /256);
serial_out(info, UART_ESI_CMD2, trigger %256);

/* Set clock scaling */
serial_out(info, UART_ESI_CMD1, ESI_SET_PRESCALAR);
serial_out(info, UART_ESI_CMD2, ESPC_SCALE);
}

static intstartup(struct esp_struct * info)
{
unsigned long flags;
int retval;
int next_irq;
struct esp_struct *next_info =0;
unsigned int num_chars;

save_flags(flags);cli();

if(info->flags & ASYNC_INITIALIZED) {
restore_flags(flags);
return0;
}

if(!info->port || !info->type) {
if(info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
restore_flags(flags);
return0;
}

if(!info->xmit_buf) {
 info->xmit_buf = (unsigned char*)get_free_page(GFP_KERNEL);
if(!info->xmit_buf) {
restore_flags(flags);
return-ENOMEM;
}
}

if(!info->tty_buf) {
 info->tty_buf = (struct tty_flip_buffer *)kmalloc(
sizeof(struct tty_flip_buffer), GFP_KERNEL);

if(!info->tty_buf) {
free_page((unsigned long) info->xmit_buf);
 info->xmit_buf =0;
restore_flags(flags);
return-ENOMEM;
}

memset(info->tty_buf,0,sizeof(struct tty_flip_buffer));
 info->tty_buf->tqueue.routine = do_ttybuf;
 info->tty_buf->tqueue.data = info;
}

 info->tty_buf->count =0;
 info->tty_buf->char_buf_ptr = info->tty_buf->char_buf;
 info->tty_buf->flag_buf_ptr = info->tty_buf->flag_buf;

#ifdef SERIAL_DEBUG_OPEN
printk("starting up ttys%d (irq %d)...", info->line, info->irq);
#endif

/* Flush the RX buffer. Using the ESI flush command may cause */
/* wild interrupts, so read all the data instead. */

serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
serial_out(info, UART_ESI_CMD1, ESI_GET_RX_AVAIL);
 num_chars =serial_in(info, UART_ESI_STAT1) <<8;
 num_chars |=serial_in(info, UART_ESI_STAT2);

while(num_chars >1) {
inw(info->port + UART_ESI_RX);
 num_chars -=2;
}

if(num_chars)
serial_in(info, UART_ESI_RX);

/* set receive character timeout */
serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
serial_out(info, UART_ESI_CMD2,0xff);

 info->stat_flags =0;

/*
 * Allocate the IRQ if necessary
 */
if(!IRQ_ports[info->irq]) {
 retval =request_irq(info->irq, rs_interrupt_single,
 SA_INTERRUPT,"esp", NULL);

if(!retval) {
int i =1;

while((i <16) && !IRQ_ports[i])
 i++;

if(i ==16) {
 dma_buffer = (char*)__get_dma_pages(GFP_KERNEL,
__get_order(DMA_BUFFER_SZ));

if(!dma_buffer)
 retval = -ENOMEM;
else
 retval =request_dma(dma,"esp");

if(retval)
free_irq(info->irq, NULL);
}
}

if(retval) {
restore_flags(flags);
if(suser()) {
if(info->tty)
set_bit(TTY_IO_ERROR,
&info->tty->flags);
return0;
}else
return retval;
}
}

 info->MCR = UART_MCR_DTR | UART_MCR_RTS | UART_MCR_OUT2;
 info->MCR_noint = UART_MCR_DTR | UART_MCR_RTS;
#if defined(__alpha__) && !defined(CONFIG_PCI)
 info->MCR |= UART_MCR_OUT1 | UART_MCR_OUT2;
 info->MCR_noint |= UART_MCR_OUT1 | UART_MCR_OUT2;
#endif

serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
serial_out(info, UART_ESI_CMD2, UART_MCR);
serial_out(info, UART_ESI_CMD2, info->MCR);

/*
 * Finally, enable interrupts
 */
/* info->IER = UART_IER_MSI | UART_IER_RLSI | UART_IER_RDI; */
 info->IER = UART_IER_RLSI | UART_IER_RDI | UART_IER_DMA_TMOUT |
 UART_IER_DMA_TC;
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);

if(info->tty)
clear_bit(TTY_IO_ERROR, &info->tty->flags);
 info->xmit_cnt = info->xmit_head = info->xmit_tail =0;

/* Remove port from "closed" 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[0] = info->next_port;

/*
 * Insert serial port into IRQ chain.
 */
 next_irq = info->irq;

do{
 next_info = IRQ_ports[next_irq];

if(++next_irq >15)
 next_irq =1;
}while(!next_info && (next_irq != info->irq));

if(!next_info) {
 info->next_port = info;
 info->prev_port = info;
}else{
 info->next_port = next_info;
 info->prev_port = next_info->prev_port;
 next_info->prev_port->next_port = info;
 next_info->prev_port = info;
}

 IRQ_ports[info->irq] = info;

/*
 * set the speed of the serial port
 */
change_speed(info);

 info->flags |= ASYNC_INITIALIZED;
restore_flags(flags);
return0;
}

/*
 * This routine will shutdown a serial port; interrupts are disabled, and
 * DTR is dropped if the hangup on close termio flag is on.
 */
static voidshutdown(struct esp_struct * info)
{
unsigned long flags;

if(!(info->flags & ASYNC_INITIALIZED))
return;

#ifdef SERIAL_DEBUG_OPEN
printk("Shutting down serial port %d (irq %d)....", info->line,
 info->irq);
#endif

save_flags(flags);cli();/* Disable interrupts */

/*
 * 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);
wake_up_interruptible(&info->break_wait);

/*
 * First unlink the serial port from the IRQ chain...
 */
 info->next_port->prev_port = info->prev_port;
 info->prev_port->next_port = info->next_port;

if(IRQ_ports[info->irq] == info) {
if((info->next_port == info) ||
(info->next_port->irq != info->irq))
 IRQ_ports[info->irq] =0;
else
 IRQ_ports[info->irq] = info->next_port;
}

/* Stick it on the "closed" chain */
 info->next_port = IRQ_ports[0];
if(info->next_port)
 info->next_port->prev_port = info;
 info->prev_port =0;
 IRQ_ports[0] = info;

/*
 * Free the IRQ, if necessary
 */
if(!IRQ_ports[info->irq]) {
int i =1;

while((i <16) && !IRQ_ports[i])
 i++;

if(i ==16) {
free_dma(dma);
free_pages((unsigned int)dma_buffer,
__get_order(DMA_BUFFER_SZ));
 dma_buffer =0;
}

free_irq(info->irq, NULL);
}

if(info->xmit_buf) {
free_page((unsigned long) info->xmit_buf);
 info->xmit_buf =0;
}

if(info->tty_buf && !info->tty_buf->tqueue.sync) {
kfree(info->tty_buf);
 info->tty_buf =0;
}

 info->IER =0;
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2,0x00);

if(!info->tty || (info->tty->termios->c_cflag & HUPCL)) {
 info->MCR &= ~(UART_MCR_DTR|UART_MCR_RTS);
 info->MCR_noint &= ~(UART_MCR_DTR|UART_MCR_RTS);
}

serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
serial_out(info, UART_ESI_CMD2, UART_MCR);
serial_out(info, UART_ESI_CMD2, info->MCR_noint);

if(info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);

 info->flags &= ~ASYNC_INITIALIZED;
restore_flags(flags);
}

/*
 * This routine is called to set the UART divisor registers to match
 * the specified baud rate for a serial port.
 */
static voidchange_speed(struct esp_struct *info)
{
unsigned short port;
int quot =0;
unsigned cflag,cval;
int i;
unsigned char flow1 =0, flow2 =0;

if(!info->tty || !info->tty->termios)
return;
 cflag = info->tty->termios->c_cflag;
if(!(port = info->port))
return;
 i = cflag & CBAUD;
if(i & CBAUDEX) {
 i &= ~CBAUDEX;
if(i <1|| i >2)
 info->tty->termios->c_cflag &= ~CBAUDEX;
else
 i +=15;
}
if(i ==15) {
if((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
 i +=1;
if((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
 i +=2;
if((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
 i +=3;
if((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
 i +=4;
if((info->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST)
 quot = info->custom_divisor;
}
if(quot) {
 info->timeout = ((1024*HZ*15*quot) /
 info->baud_base) +2;
}else if(baud_table[i] ==134) {
 quot = (2*info->baud_base /269);
 info->timeout = (1024*HZ*30/269) +2;
}else if(baud_table[i]) {
 quot = info->baud_base / baud_table[i];
 info->timeout = (1024*HZ*15/baud_table[i]) +2;
}else{
 quot =0;
 info->timeout =0;
}
if(quot) {
 info->MCR |= UART_MCR_DTR;
 info->MCR_noint |= UART_MCR_DTR;
cli();
serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
serial_out(info, UART_ESI_CMD2, UART_MCR);
serial_out(info, UART_ESI_CMD2, info->MCR);
sti();
}else{
 info->MCR &= ~UART_MCR_DTR;
 info->MCR_noint &= ~UART_MCR_DTR;
cli();
serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
serial_out(info, UART_ESI_CMD2, UART_MCR);
serial_out(info, UART_ESI_CMD2, info->MCR);
sti();
return;
}
/* byte size and parity */
switch(cflag & CSIZE) {
case CS5: cval =0x00;break;
case CS6: cval =0x01;break;
case CS7: cval =0x02;break;
case CS8: cval =0x03;break;
default: cval =0x00;break;/* too keep GCC shut... */
}
if(cflag & CSTOPB) {
 cval |=0x04;
}
if(cflag & PARENB)
 cval |= UART_LCR_PARITY;
if(!(cflag & PARODD))
 cval |= UART_LCR_EPAR;

/* CTS flow control flag and modem status interrupts */
/* info->IER &= ~UART_IER_MSI; */
if(cflag & CRTSCTS) {
 info->flags |= ASYNC_CTS_FLOW;
/* info->IER |= UART_IER_MSI; */
 flow1 =0x04;
 flow2 =0x10;
}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; */
}

/*
 * 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;

 info->ignore_status_mask =0;
#if 0
/* This should be safe, but for some broken bits of hardware... */
if(I_IGNPAR(info->tty)) {
 info->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
 info->read_status_mask |= UART_LSR_PE | UART_LSR_FE;
}
#endif
if(I_IGNBRK(info->tty)) {
 info->ignore_status_mask |= UART_LSR_BI;
 info->read_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 | \
 UART_LSR_PE | UART_LSR_FE;
 info->read_status_mask |= UART_LSR_OE | \
 UART_LSR_PE | UART_LSR_FE;
}
}

if(I_IXOFF(info->tty))
 flow1 |=0x81;

cli();
/* set baud */
serial_out(info, UART_ESI_CMD1, ESI_SET_BAUD);
serial_out(info, UART_ESI_CMD2, quot >>8);
serial_out(info, UART_ESI_CMD2, quot &0xff);

/* set data bits, parity, etc. */
serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
serial_out(info, UART_ESI_CMD2, UART_LCR);
serial_out(info, UART_ESI_CMD2, cval);

/* Enable flow control */
serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_CNTL);
serial_out(info, UART_ESI_CMD2, flow1);
serial_out(info, UART_ESI_CMD2, flow2);

/* set flow control characters (XON/XOFF only) */
if(I_IXOFF(info->tty)) {
serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_CHARS);
serial_out(info, UART_ESI_CMD2,START_CHAR(info->tty));
serial_out(info, UART_ESI_CMD2,STOP_CHAR(info->tty));
serial_out(info, UART_ESI_CMD2,0x10);
serial_out(info, UART_ESI_CMD2,0x21);
switch(cflag & CSIZE) {
case CS5:
serial_out(info, UART_ESI_CMD2,0x1f);
break;
case CS6:
serial_out(info, UART_ESI_CMD2,0x3f);
break;
case CS7:
case CS8:
serial_out(info, UART_ESI_CMD2,0x7f);
break;
default:
serial_out(info, UART_ESI_CMD2,0xff);
break;
}
}

/* Set high/low water */
serial_out(info, UART_ESI_CMD1, ESI_SET_FLOW_LVL);
serial_out(info, UART_ESI_CMD2,0x03);
serial_out(info, UART_ESI_CMD2,0xfc);
serial_out(info, UART_ESI_CMD2, (trigger +4) /256);
serial_out(info, UART_ESI_CMD2, (trigger +4) %256);

sti();
}

static voidrs_put_char(struct tty_struct *tty,unsigned char ch)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;
unsigned long flags;

if(serial_paranoia_check(info, tty->device,"rs_put_char"))
return;

if(!tty || !info->xmit_buf)
return;

save_flags(flags);cli();
if(info->xmit_cnt >= ESP_XMIT_SIZE -1) {
restore_flags(flags);
return;
}

 info->xmit_buf[info->xmit_head++] = ch;
 info->xmit_head &= ESP_XMIT_SIZE-1;
 info->xmit_cnt++;
restore_flags(flags);
}

static voidrs_flush_chars(struct tty_struct *tty)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;
unsigned long flags;

if(serial_paranoia_check(info, tty->device,"rs_flush_chars"))
return;

if(info->xmit_cnt <=0|| tty->stopped || tty->hw_stopped ||
!info->xmit_buf)
return;

save_flags(flags);cli();
if(!(info->IER & UART_IER_THRI)) {
 info->IER |= UART_IER_THRI;
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);
}
restore_flags(flags);
}

static intrs_write(struct tty_struct * tty,int from_user,
const unsigned char*buf,int count)
{
int c, total =0;
struct esp_struct *info = (struct esp_struct *)tty->driver_data;
unsigned long flags;

if(serial_paranoia_check(info, tty->device,"rs_write"))
return0;

if(!tty || !info->xmit_buf || !tmp_buf)
return0;

if(from_user)
down(&tmp_buf_sem);
save_flags(flags);
while(1) {
cli();
 c =MIN(count,MIN(ESP_XMIT_SIZE - info->xmit_cnt -1,
 ESP_XMIT_SIZE - info->xmit_head));
if(c <=0)
break;

if(from_user) {
copy_from_user(tmp_buf, buf, c);
 c =MIN(c,MIN(ESP_XMIT_SIZE - info->xmit_cnt -1,
 ESP_XMIT_SIZE - info->xmit_head));
memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
}else
memcpy(info->xmit_buf + info->xmit_head, buf, c);
 info->xmit_head = (info->xmit_head + c) & (ESP_XMIT_SIZE-1);
 info->xmit_cnt += c;
restore_flags(flags);
 buf += c;
 count -= c;
 total += c;
}
if(from_user)
up(&tmp_buf_sem);
if(info->xmit_cnt && !tty->stopped && !tty->hw_stopped &&
!(info->IER & UART_IER_THRI)) {
 info->IER |= UART_IER_THRI;
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);/* set mask */
serial_out(info, UART_ESI_CMD2, info->IER);
}
restore_flags(flags);
return total;
}

static intrs_write_room(struct tty_struct *tty)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;
int ret;

if(serial_paranoia_check(info, tty->device,"rs_write_room"))
return0;
 ret = ESP_XMIT_SIZE - info->xmit_cnt -1;
if(ret <0)
 ret =0;
return ret;
}

static intrs_chars_in_buffer(struct tty_struct *tty)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;

if(serial_paranoia_check(info, tty->device,"rs_chars_in_buffer"))
return0;
return info->xmit_cnt;
}

static voidrs_flush_buffer(struct tty_struct *tty)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;

if(serial_paranoia_check(info, tty->device,"rs_flush_buffer"))
return;
cli();
 info->xmit_cnt = info->xmit_head = info->xmit_tail =0;
sti();
wake_up_interruptible(&tty->write_wait);
if((tty->flags & (1<< TTY_DO_WRITE_WAKEUP)) &&
 tty->ldisc.write_wakeup)
(tty->ldisc.write_wakeup)(tty);
}

/*
 * ------------------------------------------------------------
 * rs_throttle()
 * 
 * This routine is called by the upper-layer tty layer to signal that
 * incoming characters should be throttled.
 * ------------------------------------------------------------
 */
static voidrs_throttle(struct tty_struct * tty)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;
#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;

 info->IER &= ~UART_IER_RDI;
cli();
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);
serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
serial_out(info, UART_ESI_CMD2,0x00);
sti();
}

static voidrs_unthrottle(struct tty_struct * tty)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;
#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;

 info->IER |= UART_IER_RDI;
cli();
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);
serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
serial_out(info, UART_ESI_CMD2,0xff);
sti();
}

/*
 * ------------------------------------------------------------
 * rs_ioctl() and friends
 * ------------------------------------------------------------
 */

static intget_serial_info(struct esp_struct * info,
struct serial_struct * retinfo)
{
struct serial_struct tmp;

if(!retinfo)
return-EFAULT;
memset(&tmp,0,sizeof(tmp));
 tmp.type = info->type;
 tmp.line = info->line;
 tmp.port = info->port;
 tmp.irq = info->irq;
 tmp.flags = info->flags;
 tmp.baud_base = info->baud_base;
 tmp.close_delay = info->close_delay;
 tmp.closing_wait = info->closing_wait;
 tmp.custom_divisor = info->custom_divisor;
 tmp.hub6 =0;
copy_to_user(retinfo,&tmp,sizeof(*retinfo));
return0;
}

static intset_serial_info(struct esp_struct * info,
struct serial_struct * new_info)
{
struct serial_struct new_serial;
struct esp_struct old_info;
unsigned int change_irq;
int retval =0;
struct esp_struct *current_async;
unsigned long flags =0;

if(!new_info)
return-EFAULT;
copy_from_user(&new_serial,new_info,sizeof(new_serial));
 old_info = *info;

if((info->type != new_serial.type) ||
(new_serial.hub6) ||
(info->port != new_serial.port) ||
(info->baud_base != new_serial.baud_base) ||
(new_serial.irq >15) ||
(new_serial.irq <1))
return-EINVAL;

 change_irq = new_serial.irq != info->irq;

if(change_irq && (info->line %8))
return-EINVAL;

if(!suser()) {
if(change_irq ||
(new_serial.baud_base != info->baud_base) ||
(new_serial.close_delay != info->close_delay) ||
((new_serial.flags & ~ASYNC_USR_MASK) !=
(info->flags & ~ASYNC_USR_MASK)))
return-EPERM;
 info->flags = ((info->flags & ~ASYNC_USR_MASK) |
(new_serial.flags & ASYNC_USR_MASK));
 info->custom_divisor = new_serial.custom_divisor;
goto check_and_exit;
}

if(new_serial.irq ==2)
 new_serial.irq =9;

if(change_irq) {
save_flags(flags);cli();

 current_async = info;
do{
if((current_async->line >= info->line) &&
(current_async->line < (info->line +8))) {
if(current_async == info) {
if(current_async->count >1) {
restore_flags(flags);
return-EBUSY;
}
}else{
restore_flags(flags);
return-EBUSY;
}
}

 current_async = current_async->next_port;
}while(current_async != info);
}

/*
 * OK, past this point, all the error checking has been done.
 * At this point, we start making changes.....
 */

 info->baud_base = new_serial.baud_base;
 info->flags = ((info->flags & ~ASYNC_FLAGS) |
(new_serial.flags & ASYNC_FLAGS));
 info->custom_divisor = new_serial.custom_divisor;
 info->close_delay = new_serial.close_delay * HZ/100;
 info->closing_wait = new_serial.closing_wait * HZ/100;

release_region(info->port,8);
if(change_irq) {
/*
 * We need to shutdown the serial port at the old
 * port/irq combination.
 */
shutdown(info);

 current_async = IRQ_ports[0];
while(current_async !=0) {
if((current_async->line >= info->line) &&
(current_async->line < (info->line +8)))
 current_async->irq = new_serial.irq;

 current_async = current_async->next_port;
}

serial_out(info, UART_ESI_CMD1, ESI_SET_ENH_IRQ);
if(info->irq ==9)
serial_out(info, UART_ESI_CMD2,0x02);
else
serial_out(info, UART_ESI_CMD2, info->irq);

restore_flags(flags);
}
if(info->type != PORT_UNKNOWN)
request_region(info->port,8,"esp(set)");


check_and_exit:
if(!info->port || !info->type)
return0;
if(info->flags & ASYNC_INITIALIZED) {
if(((old_info.flags & ASYNC_SPD_MASK) !=
(info->flags & ASYNC_SPD_MASK)) ||
(old_info.custom_divisor != info->custom_divisor))
change_speed(info);
}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 intget_lsr_info(struct esp_struct * info,unsigned int*value)
{
unsigned char status;
unsigned int result;

cli();
serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
 status =serial_in(info, UART_ESI_STAT1);
sti();
 result = ((status & UART_LSR_TEMT) ? TIOCSER_TEMT :0);
returnput_user(result,value);
}


static intget_modem_info(struct esp_struct * info,unsigned int*value)
{
unsigned char control, status;
unsigned int result;

 control = info->MCR;
cli();
serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
 status =serial_in(info, UART_ESI_STAT2);
sti();
 result = ((control & UART_MCR_RTS) ? TIOCM_RTS :0)
| ((control & UART_MCR_DTR) ? TIOCM_DTR :0)
| ((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);
returnput_user(result,value);
}

static intset_modem_info(struct esp_struct * info,unsigned int cmd,
unsigned int*value)
{
int error;
unsigned int arg;

 error =get_user(arg, value);
if(error)
return error;

switch(cmd) {
case TIOCMBIS:
if(arg & TIOCM_RTS) {
 info->MCR |= UART_MCR_RTS;
 info->MCR_noint |= UART_MCR_RTS;
}
if(arg & TIOCM_DTR) {
 info->MCR |= UART_MCR_DTR;
 info->MCR_noint |= UART_MCR_DTR;
}
break;
case TIOCMBIC:
if(arg & TIOCM_RTS) {
 info->MCR &= ~UART_MCR_RTS;
 info->MCR_noint &= ~UART_MCR_RTS;
}
if(arg & TIOCM_DTR) {
 info->MCR &= ~UART_MCR_DTR;
 info->MCR_noint &= ~UART_MCR_DTR;
}
break;
case TIOCMSET:
 info->MCR = ((info->MCR & ~(UART_MCR_RTS | UART_MCR_DTR))
| ((arg & TIOCM_RTS) ? UART_MCR_RTS :0)
| ((arg & TIOCM_DTR) ? UART_MCR_DTR :0));
 info->MCR_noint = ((info->MCR_noint
& ~(UART_MCR_RTS | UART_MCR_DTR))
| ((arg & TIOCM_RTS) ? UART_MCR_RTS :0)
| ((arg & TIOCM_DTR) ? UART_MCR_DTR :0));
break;
default:
return-EINVAL;
}
cli();
serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
serial_out(info, UART_ESI_CMD2, UART_MCR);
serial_out(info, UART_ESI_CMD2, info->MCR);
sti();
return0;
}

static intdo_autoconfig(struct esp_struct * info)
{
int retval;

if(!suser())
return-EPERM;

if(info->count >1)
return-EBUSY;

shutdown(info);

cli();
autoconfig(info);
sti();

 retval =startup(info);
if(retval)
return retval;
return0;
}


/*
 * This routine sends a break character out the serial port.
 */
static voidsend_break(struct esp_struct * info,int duration)
{
if(!info->port)
return;
cli();
serial_out(info, UART_ESI_CMD1, ESI_ISSUE_BREAK);
serial_out(info, UART_ESI_CMD2,0x01);

interruptible_sleep_on(&info->break_wait);

 current->state = TASK_INTERRUPTIBLE;
 current->timeout = jiffies + duration;
schedule();

serial_out(info, UART_ESI_CMD1, ESI_ISSUE_BREAK);
serial_out(info, UART_ESI_CMD2,0x00);
sti();
}

static intrs_ioctl(struct tty_struct *tty,struct file * file,
unsigned int cmd,unsigned long arg)
{
int error;
struct esp_struct * info = (struct esp_struct *)tty->driver_data;
int retval;
struct async_icount cprev, cnow;/* kernel counter temps */
struct serial_icounter_struct *p_cuser;/* user space */

if(serial_paranoia_check(info, tty->device,"rs_ioctl"))
return-ENODEV;

if((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
(cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD) &&
(cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT) &&
(cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
if(tty->flags & (1<< TTY_IO_ERROR))
return-EIO;
}

switch(cmd) {
case TCSBRK:/* SVID version: non-zero arg --> no break */
 retval =tty_check_change(tty);
if(retval)
return retval;
tty_wait_until_sent(tty,0);
if(!arg)
send_break(info, HZ/4);/* 1/4 second */
return0;
case TCSBRKP:/* support for POSIX tcsendbreak() */
 retval =tty_check_change(tty);
if(retval)
return retval;
tty_wait_until_sent(tty,0);
send_break(info, arg ? arg*(HZ/10) : HZ/4);
return0;
case TIOCGSOFTCAR:
returnput_user(C_CLOCAL(tty) ?1:0,
(int*) arg);
case TIOCSSOFTCAR:
 error =get_user(arg, (unsigned int*)arg);
if(error)
return error;
 tty->termios->c_cflag =
((tty->termios->c_cflag & ~CLOCAL) |
(arg ? CLOCAL :0));
return0;
case TIOCMGET:
returnget_modem_info(info, (unsigned int*) arg);
case TIOCMBIS:
case TIOCMBIC:
case TIOCMSET:
returnset_modem_info(info, cmd, (unsigned int*) arg);
case TIOCGSERIAL:
 error =verify_area(VERIFY_WRITE, (void*) arg,
sizeof(struct serial_struct));
if(error)
return error;
returnget_serial_info(info,
(struct serial_struct *) arg);
case TIOCSSERIAL:
 error =verify_area(VERIFY_READ, (void*) arg,
sizeof(struct serial_struct));
if(error)
return error;
returnset_serial_info(info,
(struct serial_struct *) arg);
case TIOCSERCONFIG:
returndo_autoconfig(info);

case TIOCSERGWILD:
returnput_user(0L, (unsigned long*) arg);

case TIOCSERGETLSR:/* Get line status register */
returnget_lsr_info(info, (unsigned int*) arg);

case TIOCSERSWILD:
if(!suser())
return-EPERM;
return0;

/*
 * 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:
cli();
 cprev = info->icount;/* note the counters on entry */
sti();
while(1) {
interruptible_sleep_on(&info->delta_msr_wait);
/* see if a signal did it */
if(current->signal & ~current->blocked)
return-ERESTARTSYS;
cli();
 cnow = info->icount;/* atomic copy */
sti();
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)) ) {
return0;
}
 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:
cli();
 cnow = info->icount;
sti();
 p_cuser = (struct serial_icounter_struct *) arg;
if((error =put_user(cnow.cts, &p_cuser->cts)))
return error;
if((error =put_user(cnow.dsr, &p_cuser->dsr)))
return error;
if((error =put_user(cnow.rng, &p_cuser->rng)))
return error;
if((error =put_user(cnow.dcd, &p_cuser->dcd)))
return error;

return0;

default:
return-ENOIOCTLCMD;
}
return0;
}

static voidrs_set_termios(struct tty_struct *tty,struct termios *old_termios)
{
struct esp_struct *info = (struct esp_struct *)tty->driver_data;

if( (tty->termios->c_cflag == old_termios->c_cflag)
&& (RELEVANT_IFLAG(tty->termios->c_iflag)
==RELEVANT_IFLAG(old_termios->c_iflag)))
return;

change_speed(info);

if((old_termios->c_cflag & CRTSCTS) &&
!(tty->termios->c_cflag & CRTSCTS)) {
 tty->hw_stopped =0;
rs_start(tty);
}

#if 0
/*
 * No need to wake up processes in open wait, since they
 * sample the CLOCAL flag once, and don't recheck it.
 * XXX It's not clear whether the current behavior is correct
 * or not. Hence, this may change.....
 */
if(!(old_termios->c_cflag & CLOCAL) &&
(tty->termios->c_cflag & CLOCAL))
wake_up_interruptible(&info->open_wait);
#endif
}

/*
 * ------------------------------------------------------------
 * 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 voidrs_close(struct tty_struct *tty,struct file * filp)
{
struct esp_struct * info = (struct esp_struct *)tty->driver_data;
unsigned long flags;
unsigned long timeout;

if(!info ||serial_paranoia_check(info, tty->device,"rs_close"))
return;

save_flags(flags);cli();

if(tty_hung_up_p(filp)) {
DBG_CNT("before DEC-hung");
 MOD_DEC_USE_COUNT;
restore_flags(flags);
return;
}

#ifdef SERIAL_DEBUG_OPEN
printk("rs_close ttys%d, count = %d\n", info->line, info->count);
#endif
if((tty->count ==1) && (info->count !=1)) {
/*
 * Uh, oh. tty->count is 1, which means that the tty
 * structure will be freed. Info->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, "
"info->count is %d\n", info->count);
 info->count =1;
}
if(--info->count <0) {
printk("rs_close: bad serial port count for ttys%d: %d\n",
 info->line, info->count);
 info->count =0;
}
if(info->count) {
DBG_CNT("before DEC-2");
 MOD_DEC_USE_COUNT;
restore_flags(flags);
return;
}
 info->flags |= ASYNC_CLOSING;
/*
 * Save the termios structure, since this port may have
 * separate termios for callout and dialin.
 */
if(info->flags & ASYNC_NORMAL_ACTIVE)
 info->normal_termios = *tty->termios;
if(info->flags & ASYNC_CALLOUT_ACTIVE)
 info->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->IER &= ~UART_IER_RDI;
 info->read_status_mask &= ~UART_LSR_DR;
if(info->flags & ASYNC_INITIALIZED) {
serial_out(info, UART_ESI_CMD1, ESI_SET_SRV_MASK);
serial_out(info, UART_ESI_CMD2, info->IER);

/* disable receive timeout */
serial_out(info, UART_ESI_CMD1, ESI_SET_RX_TIMEOUT);
serial_out(info, UART_ESI_CMD2,0x00);

/*
 * Before we drop DTR, make sure the UART transmitter
 * has completely drained; this is especially
 * important if there is a transmit FIFO!
 */
 timeout = jiffies+HZ;
serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
while((serial_in(info, UART_ESI_STAT1) !=0x03) ||
(serial_in(info, UART_ESI_STAT2) !=0xff)) {
 current->state = TASK_INTERRUPTIBLE;
 current->timeout = jiffies + info->timeout;
schedule();
if(jiffies > timeout)
break;
serial_out(info, UART_ESI_CMD1, ESI_NO_COMMAND);
serial_out(info, UART_ESI_CMD1, ESI_GET_TX_AVAIL);
}
}
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->tty_buf) {
while(info->tty_buf->tqueue.sync) {
 current->state = TASK_INTERRUPTIBLE;
 current->timeout = jiffies + HZ /10;
schedule();
}

kfree(info->tty_buf);
 info->tty_buf =0;
}

if(info->blocked_open) {
if(info->close_delay) {
 current->state = TASK_INTERRUPTIBLE;
 current->timeout = jiffies + info->close_delay;
schedule();
}
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;
restore_flags(flags);
}

/*
 * esp_hangup() --- called by tty_hangup() when a hangup is signaled.
 */
static voidesp_hangup(struct tty_struct *tty)
{
struct esp_struct * info = (struct esp_struct *)tty->driver_data;

if(serial_paranoia_check(info, tty->device,"esp_hangup"))
return;

rs_flush_buffer(tty);
shutdown(info);
 info->event =0;
 info->count =0;
 info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
 info->tty =0;
wake_up_interruptible(&info->open_wait);
}

/*
 * ------------------------------------------------------------
 * esp_open() and friends
 * ------------------------------------------------------------
 */
static intblock_til_ready(struct tty_struct *tty,struct file * filp,
struct esp_struct *info)
{
struct wait_queue wait = { current, NULL };
int retval;
int do_clocal =0;

/*
 * 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
if(info->flags & ASYNC_HUP_NOTIFY)
return-EAGAIN;
else
return-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;
return0;
}

/*
 * 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;
return0;
}

if(info->flags & ASYNC_CALLOUT_ACTIVE) {
if(info->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, info->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",
 info->line, info->count);
#endif
cli();
if(!tty_hung_up_p(filp))
 info->count--;
sti();
 info->blocked_open++;
while(1) {
cli();
if(!(info->flags & ASYNC_CALLOUT_ACTIVE)) {
unsigned int scratch;

serial_out(info, UART_ESI_CMD1, ESI_READ_UART);
serial_out(info, UART_ESI_CMD2, UART_MCR);
 scratch =serial_in(info, UART_ESI_STAT1);
serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
serial_out(info, UART_ESI_CMD2, UART_MCR);
serial_out(info, UART_ESI_CMD2,
 scratch | UART_MCR_DTR | UART_MCR_RTS);
}
sti();
 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;
}

serial_out(info, UART_ESI_CMD1, ESI_GET_UART_STAT);
if(serial_in(info, UART_ESI_STAT2) & UART_MSR_DCD)
 do_clocal =1;

if(!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
!(info->flags & ASYNC_CLOSING) &&
(do_clocal))
break;
if(current->signal & ~current->blocked) {
 retval = -ERESTARTSYS;
break;
}
#ifdef SERIAL_DEBUG_OPEN
printk("block_til_ready blocking: ttys%d, count = %d\n",
 info->line, info->count);
#endif
schedule();
}
 current->state = TASK_RUNNING;
remove_wait_queue(&info->open_wait, &wait);
if(!tty_hung_up_p(filp))
 info->count++;
 info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
printk("block_til_ready after blocking: ttys%d, count = %d\n",
 info->line, info->count);
#endif
if(retval)
return retval;
 info->flags |= ASYNC_NORMAL_ACTIVE;
return0;
}

/*
 * 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 intesp_open(struct tty_struct *tty,struct file * filp)
{
struct esp_struct *info;
int i, retval, line;
unsigned long page;

 line =MINOR(tty->device) - tty->driver.minor_start;
if((line <0) || (line >= NR_PORTS))
return-ENODEV;

/* check whether or not the port is on the closed chain */

 info = IRQ_ports[0];

while(info && (info->line != line))
 info = info->next_port;

/* if the port is not on the closed chain, look for it on the */
/* open chain */

if(!info) {
 i =1;

while((i <16) && !IRQ_ports[i])
 i++;

if(i <16) {
 info = IRQ_ports[i];

do{
if(info->line == line)
break;
 info = info->next_port;
}while(info != IRQ_ports[i]);
}
}

if(!info || (info->line != line) ||
serial_paranoia_check(info, tty->device,"esp_open"))
return-ENODEV;

#ifdef SERIAL_DEBUG_OPEN
printk("esp_open %s%d, count = %d\n", tty->driver.name, info->line,
 info->count);
#endif
 MOD_INC_USE_COUNT;
 info->count++;
 tty->driver_data = info;
 info->tty = tty;

if(!tmp_buf) {
 page =get_free_page(GFP_KERNEL);
if(!page)
return-ENOMEM;
if(tmp_buf)
free_page(page);
else
 tmp_buf = (unsigned char*) page;
}

/*
 * Start up serial port
 */
 retval =startup(info);
if(retval)
return retval;

 retval =block_til_ready(tty, filp, info);
if(retval) {
#ifdef SERIAL_DEBUG_OPEN
printk("esp_open returning after block_til_ready with %d\n",
 retval);
#endif
return retval;
}

if((info->count ==1) && (info->flags & ASYNC_SPLIT_TERMIOS)) {
if(tty->driver.subtype == SERIAL_TYPE_NORMAL)
*tty->termios = info->normal_termios;
else
*tty->termios = info->callout_termios;
change_speed(info);
}

 info->session = current->session;
 info->pgrp = current->pgrp;

#ifdef SERIAL_DEBUG_OPEN
printk("esp_open ttys%d successful...", info->line);
#endif
return0;
}

/*
 * ---------------------------------------------------------------------
 * esp_init() and friends
 *
 * esp_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 voidshow_serial_version(void)
{
printk(KERN_INFO "%s version %s (DMA %u, trigger level %u)\n",
 serial_name, serial_version, dma, trigger);
}

/*
 * This routine is called by esp_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 voidautoconfig(struct esp_struct * info)
{
unsigned char status1, status2, scratch;
unsigned port = info->port;
unsigned long flags;

 info->type = PORT_UNKNOWN;

if(!port)
return;

save_flags(flags);cli();

/*
 * Check for ESP card
 */
 scratch =serial_in(info, UART_ESI_BASE);
if(scratch ==0xf3) {
serial_out(info, UART_ESI_CMD1,0x00);
serial_out(info, UART_ESI_CMD1,0x01);
 status1 =serial_in(info, UART_ESI_STAT2);
 status2 = status1 &0x70;
if(status2 !=0x20) {
printk(" Old ESP found at %x\n",info->port);
}else{
serial_out(info, UART_ESI_CMD1,0x02);
 status1 =serial_in(info, UART_ESI_STAT1) &0x03;
if(!(info->irq)) {
if((status1 ==0x00) || (status1 ==0x02))
 info->irq =4;
else
 info->irq =3;
}
 info->type = PORT_16550A;
request_region(port,8,"esp(auto)");

/* put card in enhanced mode */
/* this prevents access through */
/* the "old" IO ports */
esp_basic_init(info);

/* clear out MCR */
serial_out(info, UART_ESI_CMD1, ESI_WRITE_UART);
serial_out(info, UART_ESI_CMD2, UART_MCR);
serial_out(info, UART_ESI_CMD2,0x00);
}
}

restore_flags(flags);
}

/*
 * The serial driver boot-time initialization code!
 */
intesp_init(void)
{
int i, offset;
struct esp_struct * info;
int esp[] = {0x100,0x140,0x180,0x200,0x240,0x280,0x300,0x380};

init_bh(ESP_BH, do_serial_bh);

for(i =0; i <16; i++) {
 IRQ_ports[i] =0;
}

if((dma !=1) && (dma !=3))
 dma = CONFIG_ESP_DMA_CHANNEL;

if((trigger <1) || (trigger >1015))
 trigger =768;

show_serial_version();

/* Initialize the tty_driver structure */

memset(&esp_driver,0,sizeof(struct tty_driver));
 esp_driver.magic = TTY_DRIVER_MAGIC;
 esp_driver.name ="ttyP";
 esp_driver.major = ESP_IN_MAJOR;
 esp_driver.minor_start =0;
 esp_driver.num = NR_PORTS;
 esp_driver.type = TTY_DRIVER_TYPE_SERIAL;
 esp_driver.subtype = SERIAL_TYPE_NORMAL;
 esp_driver.init_termios = tty_std_termios;
 esp_driver.init_termios.c_cflag =
 B9600 | CS8 | CREAD | HUPCL | CLOCAL;
 esp_driver.flags = TTY_DRIVER_REAL_RAW;
 esp_driver.refcount = &serial_refcount;
 esp_driver.table = serial_table;
 esp_driver.termios = serial_termios;
 esp_driver.termios_locked = serial_termios_locked;

 esp_driver.open = esp_open;
 esp_driver.close = rs_close;
 esp_driver.write = rs_write;
 esp_driver.put_char = rs_put_char;
 esp_driver.flush_chars = rs_flush_chars;
 esp_driver.write_room = rs_write_room;
 esp_driver.chars_in_buffer = rs_chars_in_buffer;
 esp_driver.flush_buffer = rs_flush_buffer;
 esp_driver.ioctl = rs_ioctl;
 esp_driver.throttle = rs_throttle;
 esp_driver.unthrottle = rs_unthrottle;
 esp_driver.set_termios = rs_set_termios;
 esp_driver.stop = rs_stop;
 esp_driver.start = rs_start;
 esp_driver.hangup = esp_hangup;

/*
 * The callout device is just like normal device except for
 * major number and the subtype code.
 */
 esp_callout_driver = esp_driver;
 esp_callout_driver.name ="cup";
 esp_callout_driver.major = ESP_OUT_MAJOR;
 esp_callout_driver.subtype = SERIAL_TYPE_CALLOUT;

if(tty_register_driver(&esp_driver))
panic("Couldn't register serial driver\n");
if(tty_register_driver(&esp_callout_driver))
panic("Couldn't register callout driver\n");

 info = (struct esp_struct *)kmalloc(sizeof(struct esp_struct),
 GFP_KERNEL);
if(!info)
panic("Could not allocate memory for device information\n");
memset((void*)info,0,sizeof(struct esp_struct));

 i =0;
 offset =0;

do{
 info->port = esp[i] + offset;
 info->baud_base = BASE_BAUD;
 info->custom_divisor = (divisor[i] >> (offset /2)) &0xf;
 info->flags = STD_COM_FLAGS;
if(info->custom_divisor)
 info->flags |= ASYNC_SPD_CUST;
 info->irq = irq[i];

 info->magic = ESP_MAGIC;
 info->line = (i *8) + (offset /8);
 info->tty =0;
 info->type = PORT_UNKNOWN;
 info->close_delay =5*HZ/10;
 info->closing_wait =30*HZ;
 info->tqueue.routine = do_softint;
 info->tqueue.data = info;
 info->tqueue_hangup.routine = do_serial_hangup;
 info->tqueue_hangup.data = info;
 info->callout_termios = esp_callout_driver.init_termios;
 info->normal_termios = esp_driver.init_termios;

if(info->irq ==2)
 info->irq =9;

autoconfig(info);
if(info->type == PORT_UNKNOWN) {
 i++;
 offset =0;
continue;
}
if(IRQ_ports[0])
 IRQ_ports[0]->prev_port = info;
 info->next_port = IRQ_ports[0];
 info->prev_port =0;
 IRQ_ports[0] = info;
printk(KERN_INFO "ttyP%d at 0x%04x (irq = %d) is an ESP ",
 info->line, info->port, info->irq);
if(info->line %8)
printk("secondary port\n");
else{
printk("primary port\n");
 irq[i] = info->irq;
}

 info = (struct esp_struct *)kmalloc(sizeof(struct esp_struct),
 GFP_KERNEL);
if(!info)
panic("Could not allocate memory for device information\n");
memset((void*)info,0,sizeof(struct esp_struct));

if(offset ==56) {
 i++;
 offset =0;
}else{
 offset +=8;
}
}while(i < NR_PRIMARY);

/* free the last port memory allocation */
kfree(info);

return0;
}

#ifdef MODULE

intinit_module(void)
{
returnesp_init();
}

voidcleanup_module(void)
{
unsigned long flags;
int e1, e2;
struct esp_struct *current_async, *temp_async;

/* printk("Unloading %s: version %s\n", serial_name, serial_version); */
save_flags(flags);
cli();
if((e1 =tty_unregister_driver(&esp_driver)))
printk("SERIAL: failed to unregister serial driver (%d)\n",
 e1);
if((e2 =tty_unregister_driver(&esp_callout_driver)))
printk("SERIAL: failed to unregister callout driver (%d)\n",
 e2);
restore_flags(flags);

 current_async = IRQ_ports[0];
while(current_async !=0) {
if(current_async->type != PORT_UNKNOWN)
release_region(current_async->port,8);
 current_async = current_async->next_port;
}

if(dma_buffer)
free_pages((unsigned int)dma_buffer,
__get_order(DMA_BUFFER_SZ));

if(tmp_buf)
free_page((unsigned long)tmp_buf);

/* free the port information */
 current_async = IRQ_ports[0];
while(current_async !=0) {
 temp_async = current_async->next_port;
kfree(current_async);
 current_async = temp_async;
}
}
#endif/* MODULE */