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/*********************************************************************
*
* Filename: ircomm_tty.c
* Version: 1.0
* Description: IrCOMM serial TTY driver
* Status: Experimental.
* Author: Dag Brattli <dagb@cs.uit.no>
* Created at: Sun Jun 6 21:00:56 1999
* Modified at: Wed Feb 23 00:09:02 2000
* Modified by: Dag Brattli <dagb@cs.uit.no>
* Sources: serial.c and previous IrCOMM work by Takahide Higuchi
*
* Copyright (c) 1999-2000 Dag Brattli, All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*
********************************************************************/
#include <linux/config.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/sched.h>
#include <linux/termios.h>
#include <linux/tty.h>
#include <linux/interrupt.h>
#include <asm/segment.h>
#include <asm/uaccess.h>
#include <net/irda/irda.h>
#include <net/irda/irmod.h>
#include <net/irda/ircomm_core.h>
#include <net/irda/ircomm_param.h>
#include <net/irda/ircomm_tty_attach.h>
#include <net/irda/ircomm_tty.h>
static int ircomm_tty_open(struct tty_struct *tty, struct file *filp);
static void ircomm_tty_close(struct tty_struct * tty, struct file *filp);
static int ircomm_tty_write(struct tty_struct * tty, int from_user,
const unsigned char *buf, int count);
static int ircomm_tty_write_room(struct tty_struct *tty);
static void ircomm_tty_throttle(struct tty_struct *tty);
static void ircomm_tty_unthrottle(struct tty_struct *tty);
static int ircomm_tty_chars_in_buffer(struct tty_struct *tty);
static void ircomm_tty_flush_buffer(struct tty_struct *tty);
static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch);
static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout);
static void ircomm_tty_hangup(struct tty_struct *tty);
static void ircomm_tty_do_softint(void *private_);
static void ircomm_tty_shutdown(struct ircomm_tty_cb *self);
static int ircomm_tty_data_indication(void *instance, void *sap,
struct sk_buff *skb);
static int ircomm_tty_control_indication(void *instance, void *sap,
struct sk_buff *skb);
static void ircomm_tty_flow_indication(void *instance, void *sap,
LOCAL_FLOW cmd);
#ifdef CONFIG_PROC_FS
static int ircomm_tty_read_proc(char *buf, char **start, off_t offset, int len,
int *eof, void *unused);
#endif /* CONFIG_PROC_FS */
static struct tty_driver driver;
static int ircomm_tty_refcount; /* If we manage several devices */
static struct tty_struct *ircomm_tty_table[NR_PTYS];
static struct termios *ircomm_tty_termios[NR_PTYS];
static struct termios *ircomm_tty_termios_locked[NR_PTYS];
hashbin_t *ircomm_tty = NULL;
/*
* Function ircomm_tty_init()
*
* Init IrCOMM TTY layer/driver
*
*/
int __init ircomm_tty_init(void)
{
ircomm_tty = hashbin_new(HB_LOCAL);
if (ircomm_tty == NULL) {
ERROR(__FUNCTION__ "(), can't allocate hashbin!\n");
return -ENOMEM;
}
memset(&driver, 0, sizeof(struct tty_driver));
driver.magic = TTY_DRIVER_MAGIC;
driver.driver_name = "ircomm";
#ifdef CONFIG_DEVFS_FS
driver.name = "ircomm%d";
#else
driver.name = "ircomm";
#endif
driver.major = IRCOMM_TTY_MAJOR;
driver.minor_start = IRCOMM_TTY_MINOR;
driver.num = IRCOMM_TTY_PORTS;
driver.type = TTY_DRIVER_TYPE_SERIAL;
driver.subtype = SERIAL_TYPE_NORMAL;
driver.init_termios = tty_std_termios;
driver.init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
driver.flags = TTY_DRIVER_REAL_RAW;
driver.refcount = &ircomm_tty_refcount;
driver.table = ircomm_tty_table;
driver.termios = ircomm_tty_termios;
driver.termios_locked = ircomm_tty_termios_locked;
driver.open = ircomm_tty_open;
driver.close = ircomm_tty_close;
driver.write = ircomm_tty_write;
driver.write_room = ircomm_tty_write_room;
driver.chars_in_buffer = ircomm_tty_chars_in_buffer;
driver.flush_buffer = ircomm_tty_flush_buffer;
driver.ioctl = ircomm_tty_ioctl;
driver.throttle = ircomm_tty_throttle;
driver.unthrottle = ircomm_tty_unthrottle;
driver.send_xchar = ircomm_tty_send_xchar;
driver.set_termios = ircomm_tty_set_termios;
driver.stop = ircomm_tty_stop;
driver.start = ircomm_tty_start;
driver.hangup = ircomm_tty_hangup;
driver.wait_until_sent = ircomm_tty_wait_until_sent;
#ifdef CONFIG_PROC_FS
driver.read_proc = ircomm_tty_read_proc;
#endif /* CONFIG_PROC_FS */
if (tty_register_driver(&driver)) {
ERROR(__FUNCTION__ "Couldn't register serial driver\n");
return -1;
}
return 0;
}
#ifdef MODULE
static void __ircomm_tty_cleanup(struct ircomm_tty_cb *self)
{
IRDA_DEBUG(0, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
ircomm_tty_shutdown(self);
self->magic = 0;
kfree(self);
}
/*
* Function ircomm_tty_cleanup ()
*
* Remove IrCOMM TTY layer/driver
*
*/
void ircomm_tty_cleanup(void)
{
int ret;
IRDA_DEBUG(4, __FUNCTION__"()\n");
ret = tty_unregister_driver(&driver);
if (ret) {
ERROR(__FUNCTION__ "(), failed to unregister driver\n");
return;
}
hashbin_delete(ircomm_tty, (FREE_FUNC) __ircomm_tty_cleanup);
}
#endif /* MODULE */
/*
* Function ircomm_startup (self)
*
*
*
*/
static int ircomm_tty_startup(struct ircomm_tty_cb *self)
{
notify_t notify;
int ret;
IRDA_DEBUG(2, __FUNCTION__ "()\n");
ASSERT(self != NULL, return -1;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
/* Already open */
if (self->flags & ASYNC_INITIALIZED) {
IRDA_DEBUG(2, __FUNCTION__ "(), already open so break out!\n");
return 0;
}
/* Register with IrCOMM */
irda_notify_init(¬ify);
/* These callbacks we must handle ourselves */
notify.data_indication = ircomm_tty_data_indication;
notify.udata_indication = ircomm_tty_control_indication;
notify.flow_indication = ircomm_tty_flow_indication;
/* Use the ircomm_tty interface for these ones */
notify.disconnect_indication = ircomm_tty_disconnect_indication;
notify.connect_confirm = ircomm_tty_connect_confirm;
notify.connect_indication = ircomm_tty_connect_indication;
strncpy(notify.name, "ircomm_tty", NOTIFY_MAX_NAME);
notify.instance = self;
if (!self->ircomm) {
self->ircomm = ircomm_open(¬ify, self->service_type,
self->line);
}
if (!self->ircomm)
return -ENODEV;
self->slsap_sel = self->ircomm->slsap_sel;
/* Connect IrCOMM link with remote device */
ret = ircomm_tty_attach_cable(self);
if (ret < 0) {
ERROR(__FUNCTION__ "(), error attaching cable!\n");
return ret;
}
self->flags |= ASYNC_INITIALIZED;
return 0;
}
/*
* Function ircomm_block_til_ready (self, filp)
*
*
*
*/
static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
struct file *filp)
{
DECLARE_WAITQUEUE(wait, current);
int retval;
int do_clocal = 0, extra_count = 0;
unsigned long flags;
struct tty_struct *tty;
IRDA_DEBUG(2, __FUNCTION__ "()\n");
tty = self->tty;
if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
/* this is a callout device */
/* just verify that normal device is not in use */
if (self->flags & ASYNC_NORMAL_ACTIVE)
return -EBUSY;
if ((self->flags & ASYNC_CALLOUT_ACTIVE) &&
(self->flags & ASYNC_SESSION_LOCKOUT) &&
(self->session != current->session))
return -EBUSY;
if ((self->flags & ASYNC_CALLOUT_ACTIVE) &&
(self->flags & ASYNC_PGRP_LOCKOUT) &&
(self->pgrp != current->pgrp))
return -EBUSY;
self->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)){
/* nonblock mode is set or port is not enabled */
/* just verify that callout device is not active */
if (self->flags & ASYNC_CALLOUT_ACTIVE)
return -EBUSY;
self->flags |= ASYNC_NORMAL_ACTIVE;
IRDA_DEBUG(1, __FUNCTION__ "(), O_NONBLOCK requested!\n");
return 0;
}
if (self->flags & ASYNC_CALLOUT_ACTIVE) {
if (self->normal_termios.c_cflag & CLOCAL) {
IRDA_DEBUG(1, __FUNCTION__ "(), doing CLOCAL!\n");
do_clocal = 1;
}
} else {
if (tty->termios->c_cflag & CLOCAL) {
IRDA_DEBUG(1, __FUNCTION__ "(), doing CLOCAL!\n");
do_clocal = 1;
}
}
/* Wait for carrier detect and the line to become
* free (i.e., not in use by the callout). While we are in
* this loop, self->open_count is dropped by one, so that
* mgsl_close() knows when to free things. We restore it upon
* exit, either normal or abnormal.
*/
retval = 0;
add_wait_queue(&self->open_wait, &wait);
IRDA_DEBUG(2, "%s(%d):block_til_ready before block on %s open_count=%d\n",
__FILE__,__LINE__, tty->driver.name, self->open_count );
save_flags(flags); cli();
if (!tty_hung_up_p(filp)) {
extra_count = 1;
self->open_count--;
}
restore_flags(flags);
self->blocked_open++;
while (1) {
if (!(self->flags & ASYNC_CALLOUT_ACTIVE) &&
(tty->termios->c_cflag & CBAUD)) {
save_flags(flags); cli();
self->settings.dte |= IRCOMM_RTS + IRCOMM_DTR;
ircomm_param_request(self, IRCOMM_DTE, TRUE);
restore_flags(flags);
}
current->state = TASK_INTERRUPTIBLE;
if (tty_hung_up_p(filp) || !(self->flags & ASYNC_INITIALIZED)){
retval = (self->flags & ASYNC_HUP_NOTIFY) ?
-EAGAIN : -ERESTARTSYS;
break;
}
/*
* Check if link is ready now. Even if CLOCAL is
* specified, we cannot return before the IrCOMM link is
* ready
*/
if (!(self->flags & ASYNC_CALLOUT_ACTIVE) &&
!(self->flags & ASYNC_CLOSING) &&
(do_clocal || (self->settings.dce & IRCOMM_CD)) &&
self->state == IRCOMM_TTY_READY)
{
break;
}
if (signal_pending(current)) {
retval = -ERESTARTSYS;
break;
}
IRDA_DEBUG(1, "%s(%d):block_til_ready blocking on %s open_count=%d\n",
__FILE__,__LINE__, tty->driver.name, self->open_count );
schedule();
}
__set_current_state(TASK_RUNNING);
remove_wait_queue(&self->open_wait, &wait);
if (extra_count)
self->open_count++;
self->blocked_open--;
IRDA_DEBUG(1, "%s(%d):block_til_ready after blocking on %s open_count=%d\n",
__FILE__,__LINE__, tty->driver.name, self->open_count);
if (!retval)
self->flags |= ASYNC_NORMAL_ACTIVE;
return retval;
}
/*
* Function ircomm_tty_open (tty, filp)
*
* This routine is called when a particular tty device is opened. This
* routine is mandatory; if this routine is not filled in, the attempted
* open will fail with ENODEV.
*/
static int ircomm_tty_open(struct tty_struct *tty, struct file *filp)
{
struct ircomm_tty_cb *self;
int line;
int ret;
IRDA_DEBUG(2, __FUNCTION__ "()\n");
MOD_INC_USE_COUNT;
line = MINOR(tty->device) - tty->driver.minor_start;
if ((line < 0) || (line >= IRCOMM_TTY_PORTS)) {
MOD_DEC_USE_COUNT;
return -ENODEV;
}
/* Check if instance already exists */
self = hashbin_find(ircomm_tty, line, NULL);
if (!self) {
/* No, so make new instance */
self = kmalloc(sizeof(struct ircomm_tty_cb), GFP_KERNEL);
if (self == NULL) {
ERROR(__FUNCTION__"(), kmalloc failed!\n");
MOD_DEC_USE_COUNT;
return -ENOMEM;
}
memset(self, 0, sizeof(struct ircomm_tty_cb));
self->magic = IRCOMM_TTY_MAGIC;
self->flow = FLOW_STOP;
self->line = line;
self->tqueue.routine = ircomm_tty_do_softint;
self->tqueue.data = self;
self->max_header_size = 5;
self->max_data_size = 64-self->max_header_size;
self->close_delay = 5*HZ/10;
self->closing_wait = 30*HZ;
/* Init some important stuff */
init_timer(&self->watchdog_timer);
init_waitqueue_head(&self->open_wait);
init_waitqueue_head(&self->close_wait);
/*
* Force TTY into raw mode by default which is usually what
* we want for IrCOMM and IrLPT. This way applications will
* not have to twiddle with printcap etc.
*/
tty->termios->c_iflag = 0;
tty->termios->c_oflag = 0;
/* Insert into hash */
hashbin_insert(ircomm_tty, (irda_queue_t *) self, line, NULL);
}
self->open_count++;
tty->driver_data = self;
self->tty = tty;
IRDA_DEBUG(1, __FUNCTION__"(), %s%d, count = %d\n", tty->driver.name,
self->line, self->open_count);
/* Not really used by us, but lets do it anyway */
self->tty->low_latency = (self->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
/*
* If the port is the middle of closing, bail out now
*/
if (tty_hung_up_p(filp) ||
(self->flags & ASYNC_CLOSING)) {
if (self->flags & ASYNC_CLOSING)
interruptible_sleep_on(&self->close_wait);
/* MOD_DEC_USE_COUNT; "info->tty" will cause this? */
#ifdef SERIAL_DO_RESTART
return ((self->flags & ASYNC_HUP_NOTIFY) ?
-EAGAIN : -ERESTARTSYS);
#else
return -EAGAIN;
#endif
}
/* Check if this is a "normal" ircomm device, or an irlpt device */
if (line < 0x10) {
self->service_type = IRCOMM_3_WIRE | IRCOMM_9_WIRE;
self->settings.service_type = IRCOMM_9_WIRE; /* 9 wire as default */
self->settings.dce = IRCOMM_CTS | IRCOMM_CD; /* Default line settings */
IRDA_DEBUG(2, __FUNCTION__ "(), IrCOMM device\n");
} else {
IRDA_DEBUG(2, __FUNCTION__ "(), IrLPT device\n");
self->service_type = IRCOMM_3_WIRE_RAW;
self->settings.service_type = IRCOMM_3_WIRE_RAW; /* Default */
}
ret = ircomm_tty_startup(self);
if (ret)
return ret;
ret = ircomm_tty_block_til_ready(self, filp);
if (ret) {
/* MOD_DEC_USE_COUNT; "info->tty" will cause this? */
IRDA_DEBUG(2, __FUNCTION__
"(), returning after block_til_ready with %d\n",
ret);
return ret;
}
self->session = current->session;
self->pgrp = current->pgrp;
return 0;
}
/*
* Function ircomm_tty_close (tty, filp)
*
* This routine is called when a particular tty device is closed.
*
*/
static void ircomm_tty_close(struct tty_struct *tty, struct file *filp)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
unsigned long flags;
IRDA_DEBUG(0, __FUNCTION__ "()\n");
if (!tty)
return;
save_flags(flags);
cli();
if (tty_hung_up_p(filp)) {
MOD_DEC_USE_COUNT;
restore_flags(flags);
IRDA_DEBUG(0, __FUNCTION__ "(), returning 1\n");
return;
}
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
if ((tty->count == 1) && (self->open_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.
*/
IRDA_DEBUG(0, __FUNCTION__ "(), bad serial port count; "
"tty->count is 1, state->count is %d\n",
self->open_count);
self->open_count = 1;
}
if (--self->open_count < 0) {
ERROR(__FUNCTION__
"(), bad serial port count for ttys%d: %d\n",
self->line, self->open_count);
self->open_count = 0;
}
if (self->open_count) {
MOD_DEC_USE_COUNT;
restore_flags(flags);
IRDA_DEBUG(0, __FUNCTION__ "(), open count > 0\n");
return;
}
self->flags |= ASYNC_CLOSING;
/*
* 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 (self->closing_wait != ASYNC_CLOSING_WAIT_NONE)
tty_wait_until_sent(tty, self->closing_wait);
ircomm_tty_shutdown(self);
if (tty->driver.flush_buffer)
tty->driver.flush_buffer(tty);
if (tty->ldisc.flush_buffer)
tty->ldisc.flush_buffer(tty);
tty->closing = 0;
self->tty = 0;
if (self->blocked_open) {
if (self->close_delay) {
current->state = TASK_INTERRUPTIBLE;
schedule_timeout(self->close_delay);
}
wake_up_interruptible(&self->open_wait);
}
self->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
ASYNC_CLOSING);
wake_up_interruptible(&self->close_wait);
MOD_DEC_USE_COUNT;
restore_flags(flags);
}
/*
* Function ircomm_tty_flush_buffer (tty)
*
*
*
*/
static void ircomm_tty_flush_buffer(struct tty_struct *tty)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
/*
* Let do_softint() do this to avoid race condition with
* do_softint() ;-)
*/
queue_task(&self->tqueue, &tq_immediate);
mark_bh(IMMEDIATE_BH);
}
/*
* Function ircomm_tty_do_softint (private_)
*
* We use this routine to give the write wakeup to the user at at a
* safe time (as fast as possible after write have completed). This
* can be compared to the Tx interrupt.
*/
static void ircomm_tty_do_softint(void *private_)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) private_;
struct tty_struct *tty;
unsigned long flags;
struct sk_buff *skb, *ctrl_skb;
IRDA_DEBUG(2, __FUNCTION__ "()\n");
if (!self || self->magic != IRCOMM_TTY_MAGIC)
return;
tty = self->tty;
if (!tty)
return;
/* Unlink control buffer */
save_flags(flags);
cli();
ctrl_skb = self->ctrl_skb;
self->ctrl_skb = NULL;
restore_flags(flags);
/* Flush control buffer if any */
if (ctrl_skb && self->flow == FLOW_START)
ircomm_control_request(self->ircomm, ctrl_skb);
if (tty->hw_stopped)
return;
/* Unlink transmit buffer */
save_flags(flags);
cli();
skb = self->tx_skb;
self->tx_skb = NULL;
restore_flags(flags);
/* Flush transmit buffer if any */
if (skb)
ircomm_tty_do_event(self, IRCOMM_TTY_DATA_REQUEST, skb, NULL);
/* Check if user (still) wants to be waken up */
if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
tty->ldisc.write_wakeup)
{
(tty->ldisc.write_wakeup)(tty);
}
wake_up_interruptible(&tty->write_wait);
}
/*
* Function ircomm_tty_write (tty, from_user, buf, count)
*
* This routine is called by the kernel to write a series of characters
* to the tty device. The characters may come from user space or kernel
* space. This routine will return the number of characters actually
* accepted for writing. This routine is mandatory.
*/
static int ircomm_tty_write(struct tty_struct *tty, int from_user,
const unsigned char *buf, int count)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
unsigned long flags;
struct sk_buff *skb;
int tailroom = 0;
int len = 0;
int size;
IRDA_DEBUG(2, __FUNCTION__ "(), count=%d, hw_stopped=%d\n", count,
tty->hw_stopped);
ASSERT(self != NULL, return -1;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
save_flags(flags);
cli();
/* Fetch current transmit buffer */
skb = self->tx_skb;
/*
* Send out all the data we get, possibly as multiple fragmented
* frames, but this will only happen if the data is larger than the
* max data size. The normal case however is just the opposite, and
* this function may be called multiple times, and will then actually
* defragment the data and send it out as one packet as soon as
* possible, but at a safer point in time
*/
while (count) {
size = count;
/* Adjust data size to the max data size */
if (size > self->max_data_size)
size = self->max_data_size;
/*
* Do we already have a buffer ready for transmit, or do
* we need to allocate a new frame
*/
if (skb) {
/*
* Any room for more data at the end of the current
* transmit buffer? Cannot use skb_tailroom, since
* dev_alloc_skb gives us a larger skb than we
* requested
*/
if ((tailroom = (self->max_data_size-skb->len)) > 0) {
/* Adjust data to tailroom */
if (size > tailroom)
size = tailroom;
} else {
/*
* Current transmit frame is full, so break
* out, so we can send it as soon as possible
*/
break;
}
} else {
/* Prepare a full sized frame */
skb = dev_alloc_skb(self->max_data_size+
self->max_header_size);
if (!skb) {
restore_flags(flags);
return -ENOBUFS;
}
skb_reserve(skb, self->max_header_size);
self->tx_skb = skb;
}
/* Copy data */
if (from_user)
copy_from_user(skb_put(skb,size), buf+len, size);
else
memcpy(skb_put(skb,size), buf+len, size);
count -= size;
len += size;
}
restore_flags(flags);
/*
* Schedule a new thread which will transmit the frame as soon
* as possible, but at a safe point in time. We do this so the
* "user" can give us data multiple times, as PPP does (because of
* its 256 byte tx buffer). We will then defragment and send out
* all this data as one single packet.
*/
queue_task(&self->tqueue, &tq_immediate);
mark_bh(IMMEDIATE_BH);
return len;
}
/*
* Function ircomm_tty_write_room (tty)
*
* This routine returns the numbers of characters the tty driver will
* accept for queuing to be written. This number is subject to change as
* output buffers get emptied, or if the output flow control is acted.
*/
static int ircomm_tty_write_room(struct tty_struct *tty)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
unsigned long flags;
int ret;
ASSERT(self != NULL, return -1;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
/* Check if we are allowed to transmit any data */
if (tty->hw_stopped)
ret = 0;
else {
save_flags(flags);
cli();
if (self->tx_skb)
ret = self->max_data_size - self->tx_skb->len;
else
ret = self->max_data_size;
restore_flags(flags);
}
IRDA_DEBUG(2, __FUNCTION__ "(), ret=%d\n", ret);
return ret;
}
/*
* Function ircomm_tty_wait_until_sent (tty, timeout)
*
* This routine waits until the device has written out all of the
* characters in its transmitter FIFO.
*/
static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
unsigned long orig_jiffies, poll_time;
IRDA_DEBUG(2, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
orig_jiffies = jiffies;
/* Set poll time to 200 ms */
poll_time = IRDA_MIN(timeout, MSECS_TO_JIFFIES(200));
while (self->tx_skb && self->tx_skb->len) {
current->state = TASK_INTERRUPTIBLE;
schedule_timeout(poll_time);
if (signal_pending(current))
break;
if (timeout && time_after(jiffies, orig_jiffies + timeout))
break;
}
current->state = TASK_RUNNING;
}
/*
* Function ircomm_tty_throttle (tty)
*
* This routine notifies the tty driver that input buffers for the line
* discipline are close to full, and it should somehow signal that no
* more characters should be sent to the tty.
*/
static void ircomm_tty_throttle(struct tty_struct *tty)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
IRDA_DEBUG(2, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
/* Software flow control? */
if (I_IXOFF(tty))
ircomm_tty_send_xchar(tty, STOP_CHAR(tty));
/* Hardware flow control? */
if (tty->termios->c_cflag & CRTSCTS) {
self->settings.dte &= ~IRCOMM_RTS;
self->settings.dte |= IRCOMM_DELTA_RTS;
ircomm_param_request(self, IRCOMM_DTE, TRUE);
}
ircomm_flow_request(self->ircomm, FLOW_STOP);
}
/*
* Function ircomm_tty_unthrottle (tty)
*
* This routine notifies the tty drivers that it should signals that
* characters can now be sent to the tty without fear of overrunning the
* input buffers of the line disciplines.
*/
static void ircomm_tty_unthrottle(struct tty_struct *tty)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
IRDA_DEBUG(2, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
/* Using software flow control? */
if (I_IXOFF(tty)) {
ircomm_tty_send_xchar(tty, START_CHAR(tty));
}
/* Using hardware flow control? */
if (tty->termios->c_cflag & CRTSCTS) {
self->settings.dte |= (IRCOMM_RTS|IRCOMM_DELTA_RTS);
ircomm_param_request(self, IRCOMM_DTE, TRUE);
IRDA_DEBUG(1, __FUNCTION__"(), FLOW_START\n");
}
ircomm_flow_request(self->ircomm, FLOW_START);
}
/*
* Function ircomm_tty_chars_in_buffer (tty)
*
* Indicates if there are any data in the buffer
*
*/
static int ircomm_tty_chars_in_buffer(struct tty_struct *tty)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
unsigned long flags;
int len = 0;
ASSERT(self != NULL, return -1;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
save_flags(flags);
cli();
if (self->tx_skb)
len = self->tx_skb->len;
restore_flags(flags);
return len;
}
static void ircomm_tty_shutdown(struct ircomm_tty_cb *self)
{
unsigned long flags;
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
IRDA_DEBUG(0, __FUNCTION__ "()\n");
if (!(self->flags & ASYNC_INITIALIZED))
return;
save_flags(flags);
cli();
del_timer(&self->watchdog_timer);
/* Free parameter buffer */
if (self->ctrl_skb) {
dev_kfree_skb(self->ctrl_skb);
self->ctrl_skb = NULL;
}
/* Free transmit buffer */
if (self->tx_skb) {
dev_kfree_skb(self->tx_skb);
self->tx_skb = NULL;
}
ircomm_tty_detach_cable(self);
if (self->ircomm) {
ircomm_close(self->ircomm);
self->ircomm = NULL;
}
self->flags &= ~ASYNC_INITIALIZED;
restore_flags(flags);
}
/*
* Function ircomm_tty_hangup (tty)
*
* This routine notifies the tty driver that it should hangup the tty
* device.
*
*/
static void ircomm_tty_hangup(struct tty_struct *tty)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
IRDA_DEBUG(0, __FUNCTION__"()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
if (!tty)
return;
/* ircomm_tty_flush_buffer(tty); */
ircomm_tty_shutdown(self);
self->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
self->tty = 0;
self->open_count = 0;
wake_up_interruptible(&self->open_wait);
}
/*
* Function ircomm_tty_send_xchar (tty, ch)
*
* This routine is used to send a high-priority XON/XOFF character to
* the device.
*/
static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch)
{
IRDA_DEBUG(0, __FUNCTION__"(), not impl\n");
}
/*
* Function ircomm_tty_start (tty)
*
* This routine notifies the tty driver that it resume sending
* characters to the tty device.
*/
void ircomm_tty_start(struct tty_struct *tty)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
ircomm_flow_request(self->ircomm, FLOW_START);
}
/*
* Function ircomm_tty_stop (tty)
*
* This routine notifies the tty driver that it should stop outputting
* characters to the tty device.
*/
void ircomm_tty_stop(struct tty_struct *tty)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
ircomm_flow_request(self->ircomm, FLOW_STOP);
}
/*
* Function ircomm_check_modem_status (self)
*
* Check for any changes in the DCE's line settings. This function should
* be called whenever the dce parameter settings changes, to update the
* flow control settings and other things
*/
void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self)
{
struct tty_struct *tty;
int status;
IRDA_DEBUG(0, __FUNCTION__ "()\n");
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
tty = self->tty;
status = self->settings.dce;
if (status & IRCOMM_DCE_DELTA_ANY) {
/*wake_up_interruptible(&self->delta_msr_wait);*/
}
if ((self->flags & ASYNC_CHECK_CD) && (status & IRCOMM_DELTA_CD)) {
IRDA_DEBUG(2, __FUNCTION__
"(), ircomm%d CD now %s...\n", self->line,
(status & IRCOMM_CD) ? "on" : "off");
if (status & IRCOMM_CD) {
wake_up_interruptible(&self->open_wait);
} else if (!((self->flags & ASYNC_CALLOUT_ACTIVE) &&
(self->flags & ASYNC_CALLOUT_NOHUP)))
{
IRDA_DEBUG(2, __FUNCTION__
"(), Doing serial hangup..\n");
if (tty)
tty_hangup(tty);
/* Hangup will remote the tty, so better break out */
return;
}
}
if (self->flags & ASYNC_CTS_FLOW) {
if (tty->hw_stopped) {
if (status & IRCOMM_CTS) {
IRDA_DEBUG(2, __FUNCTION__
"(), CTS tx start...\n");
tty->hw_stopped = 0;
/* Wake up processes blocked on open */
wake_up_interruptible(&self->open_wait);
queue_task(&self->tqueue, &tq_immediate);
mark_bh(IMMEDIATE_BH);
return;
}
} else {
if (!(status & IRCOMM_CTS)) {
IRDA_DEBUG(2, __FUNCTION__
"(), CTS tx stop...\n");
tty->hw_stopped = 1;
}
}
}
}
/*
* Function ircomm_tty_data_indication (instance, sap, skb)
*
* Handle incoming data, and deliver it to the line discipline
*
*/
static int ircomm_tty_data_indication(void *instance, void *sap,
struct sk_buff *skb)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
IRDA_DEBUG(2, __FUNCTION__"()\n");
ASSERT(self != NULL, return -1;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
ASSERT(skb != NULL, return -1;);
if (!self->tty) {
IRDA_DEBUG(0, __FUNCTION__ "(), no tty!\n");
dev_kfree_skb(skb);
return 0;
}
/*
* If we receive data when hardware is stopped then something is wrong.
* We try to poll the peers line settings to check if we are up todate.
* Devices like WinCE can do this, and since they don't send any
* params, we can just as well declare the hardware for running.
*/
if (self->tty->hw_stopped && (self->flow == FLOW_START)) {
IRDA_DEBUG(0, __FUNCTION__ "(), polling for line settings!\n");
ircomm_param_request(self, IRCOMM_POLL, TRUE);
/* We can just as well declare the hardware for running */
ircomm_tty_send_initial_parameters(self);
ircomm_tty_link_established(self);
}
/*
* Just give it over to the line discipline. There is no need to
* involve the flip buffers, since we are not running in an interrupt
* handler
*/
self->tty->ldisc.receive_buf(self->tty, skb->data, NULL, skb->len);
dev_kfree_skb(skb);
return 0;
}
/*
* Function ircomm_tty_control_indication (instance, sap, skb)
*
* Parse all incoming parameters (easy!)
*
*/
static int ircomm_tty_control_indication(void *instance, void *sap,
struct sk_buff *skb)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
int clen;
IRDA_DEBUG(4, __FUNCTION__"()\n");
ASSERT(self != NULL, return -1;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
ASSERT(skb != NULL, return -1;);
clen = skb->data[0];
irda_param_extract_all(self, skb->data+1, IRDA_MIN(skb->len-1, clen),
&ircomm_param_info);
dev_kfree_skb(skb);
return 0;
}
/*
* Function ircomm_tty_flow_indication (instance, sap, cmd)
*
* This function is called by IrTTP when it wants us to slow down the
* transmission of data. We just mark the hardware as stopped, and wait
* for IrTTP to notify us that things are OK again.
*/
static void ircomm_tty_flow_indication(void *instance, void *sap,
LOCAL_FLOW cmd)
{
struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
struct tty_struct *tty;
ASSERT(self != NULL, return;);
ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
tty = self->tty;
switch (cmd) {
case FLOW_START:
IRDA_DEBUG(2, __FUNCTION__ "(), hw start!\n");
tty->hw_stopped = 0;
/* ircomm_tty_do_softint will take care of the rest */
queue_task(&self->tqueue, &tq_immediate);
mark_bh(IMMEDIATE_BH);
break;
default: /* If we get here, something is very wrong, better stop */
case FLOW_STOP:
IRDA_DEBUG(2, __FUNCTION__ "(), hw stopped!\n");
tty->hw_stopped = 1;
break;
}
self->flow = cmd;
}
static int ircomm_tty_line_info(struct ircomm_tty_cb *self, char *buf)
{
int ret=0;
ret += sprintf(buf+ret, "State: %s\n", ircomm_tty_state[self->state]);
ret += sprintf(buf+ret, "Service type: ");
if (self->service_type & IRCOMM_9_WIRE)
ret += sprintf(buf+ret, "9_WIRE");
else if (self->service_type & IRCOMM_3_WIRE)
ret += sprintf(buf+ret, "3_WIRE");
else if (self->service_type & IRCOMM_3_WIRE_RAW)
ret += sprintf(buf+ret, "3_WIRE_RAW");
else
ret += sprintf(buf+ret, "No common service type!\n");
ret += sprintf(buf+ret, "\n");
ret += sprintf(buf+ret, "Port name: %s\n", self->settings.port_name);
ret += sprintf(buf+ret, "DTE status: ");
if (self->settings.dte & IRCOMM_RTS)
ret += sprintf(buf+ret, "RTS|");
if (self->settings.dte & IRCOMM_DTR)
ret += sprintf(buf+ret, "DTR|");
if (self->settings.dte)
ret--; /* remove the last | */
ret += sprintf(buf+ret, "\n");
ret += sprintf(buf+ret, "DCE status: ");
if (self->settings.dce & IRCOMM_CTS)
ret += sprintf(buf+ret, "CTS|");
if (self->settings.dce & IRCOMM_DSR)
ret += sprintf(buf+ret, "DSR|");
if (self->settings.dce & IRCOMM_CD)
ret += sprintf(buf+ret, "CD|");
if (self->settings.dce & IRCOMM_RI)
ret += sprintf(buf+ret, "RI|");
if (self->settings.dce)
ret--; /* remove the last | */
ret += sprintf(buf+ret, "\n");
ret += sprintf(buf+ret, "Configuration: ");
if (!self->settings.null_modem)
ret += sprintf(buf+ret, "DTE <-> DCE\n");
else
ret += sprintf(buf+ret,
"DTE <-> DTE (null modem emulation)\n");
ret += sprintf(buf+ret, "Data rate: %d\n", self->settings.data_rate);
ret += sprintf(buf+ret, "Flow control: ");
if (self->settings.flow_control & IRCOMM_XON_XOFF_IN)
ret += sprintf(buf+ret, "XON_XOFF_IN|");
if (self->settings.flow_control & IRCOMM_XON_XOFF_OUT)
ret += sprintf(buf+ret, "XON_XOFF_OUT|");
if (self->settings.flow_control & IRCOMM_RTS_CTS_IN)
ret += sprintf(buf+ret, "RTS_CTS_IN|");
if (self->settings.flow_control & IRCOMM_RTS_CTS_OUT)
ret += sprintf(buf+ret, "RTS_CTS_OUT|");
if (self->settings.flow_control & IRCOMM_DSR_DTR_IN)
ret += sprintf(buf+ret, "DSR_DTR_IN|");
if (self->settings.flow_control & IRCOMM_DSR_DTR_OUT)
ret += sprintf(buf+ret, "DSR_DTR_OUT|");
if (self->settings.flow_control & IRCOMM_ENQ_ACK_IN)
ret += sprintf(buf+ret, "ENQ_ACK_IN|");
if (self->settings.flow_control & IRCOMM_ENQ_ACK_OUT)
ret += sprintf(buf+ret, "ENQ_ACK_OUT|");
if (self->settings.flow_control)
ret--; /* remove the last | */
ret += sprintf(buf+ret, "\n");
ret += sprintf(buf+ret, "Flags: ");
if (self->flags & ASYNC_CTS_FLOW)
ret += sprintf(buf+ret, "ASYNC_CTS_FLOW|");
if (self->flags & ASYNC_CHECK_CD)
ret += sprintf(buf+ret, "ASYNC_CHECK_CD|");
if (self->flags & ASYNC_INITIALIZED)
ret += sprintf(buf+ret, "ASYNC_INITIALIZED|");
if (self->flags & ASYNC_LOW_LATENCY)
ret += sprintf(buf+ret, "ASYNC_LOW_LATENCY|");
if (self->flags & ASYNC_CLOSING)
ret += sprintf(buf+ret, "ASYNC_CLOSING|");
if (self->flags & ASYNC_NORMAL_ACTIVE)
ret += sprintf(buf+ret, "ASYNC_NORMAL_ACTIVE|");
if (self->flags & ASYNC_CALLOUT_ACTIVE)
ret += sprintf(buf+ret, "ASYNC_CALLOUT_ACTIVE|");
if (self->flags)
ret--; /* remove the last | */
ret += sprintf(buf+ret, "\n");
ret += sprintf(buf+ret, "Role: %s\n", self->client ?
"client" : "server");
ret += sprintf(buf+ret, "Open count: %d\n", self->open_count);
ret += sprintf(buf+ret, "Max data size: %d\n", self->max_data_size);
ret += sprintf(buf+ret, "Max header size: %d\n", self->max_header_size);
if (self->tty)
ret += sprintf(buf+ret, "Hardware: %s\n",
self->tty->hw_stopped ? "Stopped" : "Running");
ret += sprintf(buf+ret, "\n");
return ret;
}
/*
* Function ircomm_tty_read_proc (buf, start, offset, len, eof, unused)
*
*
*
*/
#ifdef CONFIG_PROC_FS
static int ircomm_tty_read_proc(char *buf, char **start, off_t offset, int len,
int *eof, void *unused)
{
struct ircomm_tty_cb *self;
int count = 0, l;
off_t begin = 0;
self = (struct ircomm_tty_cb *) hashbin_get_first(ircomm_tty);
while ((self != NULL) && (count < 4000)) {
if (self->magic != IRCOMM_TTY_MAGIC)
return 0;
l = ircomm_tty_line_info(self, buf + count);
count += l;
if (count+begin > offset+len)
goto done;
if (count+begin < offset) {
begin += count;
count = 0;
}
self = (struct ircomm_tty_cb *) hashbin_get_next(ircomm_tty);
}
*eof = 1;
done:
if (offset >= count+begin)
return 0;
*start = buf + (offset-begin);
return ((len < begin+count-offset) ? len : begin+count-offset);
}
#endif /* CONFIG_PROC_FS */
#ifdef MODULE
MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
MODULE_DESCRIPTION("IrCOMM serial TTY driver");
MODULE_LICENSE("GPL");
int init_module(void)
{
return ircomm_tty_init();
}
void cleanup_module(void)
{
ircomm_tty_cleanup();
}
#endif /* MODULE */
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