net/irda/ircomm/ircomm_tty.c

   1 /*********************************************************************
   2  *
   3  * Filename:      ircomm_tty.c
   4  * Version:       1.0
   5  * Description:   IrCOMM serial TTY driver
   6  * Status:        Experimental.
   7  * Author:        Dag Brattli <dagb@cs.uit.no>
   8  * Created at:    Sun Jun  6 21:00:56 1999
   9  * Modified at:   Wed Feb 23 00:09:02 2000
  10  * Modified by:   Dag Brattli <dagb@cs.uit.no>
  11  * Sources:       serial.c and previous IrCOMM work by Takahide Higuchi
  12  *
  13  *     Copyright (c) 1999-2000 Dag Brattli, All Rights Reserved.
  14  *     Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
  15  *
  16  *     This program is free software; you can redistribute it and/or
  17  *     modify it under the terms of the GNU General Public License as
  18  *     published by the Free Software Foundation; either version 2 of
  19  *     the License, or (at your option) any later version.
  20  *
  21  *     This program is distributed in the hope that it will be useful,
  22  *     but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  24  *     GNU General Public License for more details.
  25  *
  26  *     You should have received a copy of the GNU General Public License
  27  *     along with this program; if not, write to the Free Software
  28  *     Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  29  *     MA 02111-1307 USA
  30  *
  31  ********************************************************************/
  32
  33 #include <linux/config.h>
  34 #include <linux/init.h>
  35 #include <linux/module.h>
  36 #include <linux/fs.h>
  37 #include <linux/sched.h>
  38 #include <linux/termios.h>
  39 #include <linux/tty.h>
  40 #include <linux/interrupt.h>
  41 #include <linux/device.h>               /* for MODULE_ALIAS_CHARDEV_MAJOR */
  42
  43 #include <asm/uaccess.h>
  44
  45 #include <net/irda/irda.h>
  46 #include <net/irda/irmod.h>
  47
  48 #include <net/irda/ircomm_core.h>
  49 #include <net/irda/ircomm_param.h>
  50 #include <net/irda/ircomm_tty_attach.h>
  51 #include <net/irda/ircomm_tty.h>
  52
  53 static int  ircomm_tty_open(struct tty_struct *tty, struct file *filp);
  54 static void ircomm_tty_close(struct tty_struct * tty, struct file *filp);
  55 static int  ircomm_tty_write(struct tty_struct * tty, int from_user,
  56                              const unsigned char *buf, int count);
  57 static int  ircomm_tty_write_room(struct tty_struct *tty);
  58 static void ircomm_tty_throttle(struct tty_struct *tty);
  59 static void ircomm_tty_unthrottle(struct tty_struct *tty);
  60 static int  ircomm_tty_chars_in_buffer(struct tty_struct *tty);
  61 static void ircomm_tty_flush_buffer(struct tty_struct *tty);
  62 static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch);
  63 static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout);
  64 static void ircomm_tty_hangup(struct tty_struct *tty);
  65 static void ircomm_tty_do_softint(void *private_);
  66 static void ircomm_tty_shutdown(struct ircomm_tty_cb *self);
  67
  68 static int ircomm_tty_data_indication(void *instance, void *sap,
  69                                       struct sk_buff *skb);
  70 static int ircomm_tty_control_indication(void *instance, void *sap,
  71                                          struct sk_buff *skb);
  72 static void ircomm_tty_flow_indication(void *instance, void *sap,
  73                                        LOCAL_FLOW cmd);
  74 #ifdef CONFIG_PROC_FS
  75 static int ircomm_tty_read_proc(char *buf, char **start, off_t offset, int len,
  76                                 int *eof, void *unused);
  77 #endif /* CONFIG_PROC_FS */
  78 static struct tty_driver *driver;
  79
  80 hashbin_t *ircomm_tty = NULL;
  81
  82 static struct tty_operations ops = {
  83         .open            = ircomm_tty_open,
  84         .close           = ircomm_tty_close,
  85         .write           = ircomm_tty_write,
  86         .write_room      = ircomm_tty_write_room,
  87         .chars_in_buffer = ircomm_tty_chars_in_buffer,
  88         .flush_buffer    = ircomm_tty_flush_buffer,
  89         .ioctl           = ircomm_tty_ioctl,    /* ircomm_tty_ioctl.c */
  90         .tiocmget        = ircomm_tty_tiocmget, /* ircomm_tty_ioctl.c */
  91         .tiocmset        = ircomm_tty_tiocmset, /* ircomm_tty_ioctl.c */
  92         .throttle        = ircomm_tty_throttle,
  93         .unthrottle      = ircomm_tty_unthrottle,
  94         .send_xchar      = ircomm_tty_send_xchar,
  95         .set_termios     = ircomm_tty_set_termios,
  96         .stop            = ircomm_tty_stop,
  97         .start           = ircomm_tty_start,
  98         .hangup          = ircomm_tty_hangup,
  99         .wait_until_sent = ircomm_tty_wait_until_sent,
 100 #ifdef CONFIG_PROC_FS
 101         .read_proc       = ircomm_tty_read_proc,
 102 #endif /* CONFIG_PROC_FS */
 103 };
 104
 105 /*
 106  * Function ircomm_tty_init()
 107  *
 108  *    Init IrCOMM TTY layer/driver
 109  *
 110  */
 111 int __init ircomm_tty_init(void)
 112 {
 113         driver = alloc_tty_driver(IRCOMM_TTY_PORTS);
 114         if (!driver)
 115                 return -ENOMEM;
 116         ircomm_tty = hashbin_new(HB_LOCK);
 117         if (ircomm_tty == NULL) {
 118                 ERROR("%s(), can't allocate hashbin!\n", __FUNCTION__);
 119                 put_tty_driver(driver);
 120                 return -ENOMEM;
 121         }
 122
 123         driver->owner           = THIS_MODULE;
 124         driver->driver_name     = "ircomm";
 125         driver->name            = "ircomm";
 126         driver->devfs_name      = "ircomm";
 127         driver->major           = IRCOMM_TTY_MAJOR;
 128         driver->minor_start     = IRCOMM_TTY_MINOR;
 129         driver->type            = TTY_DRIVER_TYPE_SERIAL;
 130         driver->subtype         = SERIAL_TYPE_NORMAL;
 131         driver->init_termios    = tty_std_termios;
 132         driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
 133         driver->flags           = TTY_DRIVER_REAL_RAW;
 134         tty_set_operations(driver, &ops);
 135         if (tty_register_driver(driver)) {
 136                 ERROR("%s(): Couldn't register serial driver\n", __FUNCTION__);
 137                 put_tty_driver(driver);
 138                 return -1;
 139         }
 140         return 0;
 141 }
 142
 143 static void __exit __ircomm_tty_cleanup(struct ircomm_tty_cb *self)
 144 {
 145         IRDA_DEBUG(0, "%s()\n", __FUNCTION__ );
 146
 147         ASSERT(self != NULL, return;);
 148         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
 149
 150         ircomm_tty_shutdown(self);
 151
 152         self->magic = 0;
 153         kfree(self);
 154 }
 155
 156 /*
 157  * Function ircomm_tty_cleanup ()
 158  *
 159  *    Remove IrCOMM TTY layer/driver
 160  *
 161  */
 162 void __exit ircomm_tty_cleanup(void)
 163 {
 164         int ret;
 165
 166         IRDA_DEBUG(4, "%s()\n", __FUNCTION__ );
 167
 168         ret = tty_unregister_driver(driver);
 169         if (ret) {
 170                 ERROR("%s(), failed to unregister driver\n", __FUNCTION__);
 171                 return;
 172         }
 173
 174         hashbin_delete(ircomm_tty, (FREE_FUNC) __ircomm_tty_cleanup);
 175         put_tty_driver(driver);
 176 }
 177
 178 /*
 179  * Function ircomm_startup (self)
 180  *
 181  *
 182  *
 183  */
 184 static int ircomm_tty_startup(struct ircomm_tty_cb *self)
 185 {
 186         notify_t notify;
 187         int ret = -ENODEV;
 188
 189         IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
 190
 191         ASSERT(self != NULL, return -1;);
 192         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
 193
 194         /* Check if already open */
 195         if (test_and_set_bit(ASYNC_B_INITIALIZED, &self->flags)) {
 196                 IRDA_DEBUG(2, "%s(), already open so break out!\n", __FUNCTION__ );
 197                 return 0;
 198         }
 199
 200         /* Register with IrCOMM */
 201         irda_notify_init(&notify);
 202         /* These callbacks we must handle ourselves */
 203         notify.data_indication       = ircomm_tty_data_indication;
 204         notify.udata_indication      = ircomm_tty_control_indication;
 205         notify.flow_indication       = ircomm_tty_flow_indication;
 206
 207         /* Use the ircomm_tty interface for these ones */
 208         notify.disconnect_indication = ircomm_tty_disconnect_indication;
 209         notify.connect_confirm       = ircomm_tty_connect_confirm;
 210         notify.connect_indication    = ircomm_tty_connect_indication;
 211         strlcpy(notify.name, "ircomm_tty", sizeof(notify.name));
 212         notify.instance = self;
 213
 214         if (!self->ircomm) {
 215                 self->ircomm = ircomm_open(&notify, self->service_type,
 216                                            self->line);
 217         }
 218         if (!self->ircomm)
 219                 goto err;
 220
 221         self->slsap_sel = self->ircomm->slsap_sel;
 222
 223         /* Connect IrCOMM link with remote device */
 224         ret = ircomm_tty_attach_cable(self);
 225         if (ret < 0) {
 226                 ERROR("%s(), error attaching cable!\n", __FUNCTION__);
 227                 goto err;
 228         }
 229
 230         return 0;
 231 err:
 232         clear_bit(ASYNC_B_INITIALIZED, &self->flags);
 233         return ret;
 234 }
 235
 236 /*
 237  * Function ircomm_block_til_ready (self, filp)
 238  *
 239  *
 240  *
 241  */
 242 static int ircomm_tty_block_til_ready(struct ircomm_tty_cb *self,
 243                                       struct file *filp)
 244 {
 245         DECLARE_WAITQUEUE(wait, current);
 246         int             retval;
 247         int             do_clocal = 0, extra_count = 0;
 248         unsigned long   flags;
 249         struct tty_struct *tty;
 250
 251         IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
 252
 253         tty = self->tty;
 254
 255         /*
 256          * If non-blocking mode is set, or the port is not enabled,
 257          * then make the check up front and then exit.
 258          */
 259         if (filp->f_flags & O_NONBLOCK || tty->flags & (1 << TTY_IO_ERROR)){
 260                 /* nonblock mode is set or port is not enabled */
 261                 self->flags |= ASYNC_NORMAL_ACTIVE;
 262                 IRDA_DEBUG(1, "%s(), O_NONBLOCK requested!\n", __FUNCTION__ );
 263                 return 0;
 264         }
 265
 266         if (tty->termios->c_cflag & CLOCAL) {
 267                 IRDA_DEBUG(1, "%s(), doing CLOCAL!\n", __FUNCTION__ );
 268                 do_clocal = 1;
 269         }
 270
 271         /* Wait for carrier detect and the line to become
 272          * free (i.e., not in use by the callout).  While we are in
 273          * this loop, self->open_count is dropped by one, so that
 274          * mgsl_close() knows when to free things.  We restore it upon
 275          * exit, either normal or abnormal.
 276          */
 277
 278         retval = 0;
 279         add_wait_queue(&self->open_wait, &wait);
 280
 281         IRDA_DEBUG(2, "%s(%d):block_til_ready before block on %s open_count=%d\n",
 282               __FILE__,__LINE__, tty->driver->name, self->open_count );
 283
 284         /* As far as I can see, we protect open_count - Jean II */
 285         spin_lock_irqsave(&self->spinlock, flags);
 286         if (!tty_hung_up_p(filp)) {
 287                 extra_count = 1;
 288                 self->open_count--;
 289         }
 290         spin_unlock_irqrestore(&self->spinlock, flags);
 291         self->blocked_open++;
 292
 293         while (1) {
 294                 if (tty->termios->c_cflag & CBAUD) {
 295                         /* Here, we use to lock those two guys, but
 296                          * as ircomm_param_request() does it itself,
 297                          * I don't see the point (and I see the deadlock).
 298                          * Jean II */
 299                         self->settings.dte |= IRCOMM_RTS + IRCOMM_DTR;
 300
 301                         ircomm_param_request(self, IRCOMM_DTE, TRUE);
 302                 }
 303
 304                 current->state = TASK_INTERRUPTIBLE;
 305
 306                 if (tty_hung_up_p(filp) ||
 307                     !test_bit(ASYNC_B_INITIALIZED, &self->flags)) {
 308                         retval = (self->flags & ASYNC_HUP_NOTIFY) ?
 309                                         -EAGAIN : -ERESTARTSYS;
 310                         break;
 311                 }
 312
 313                 /*
 314                  * Check if link is ready now. Even if CLOCAL is
 315                  * specified, we cannot return before the IrCOMM link is
 316                  * ready
 317                  */
 318                 if (!test_bit(ASYNC_B_CLOSING, &self->flags) &&
 319                     (do_clocal || (self->settings.dce & IRCOMM_CD)) &&
 320                     self->state == IRCOMM_TTY_READY)
 321                 {
 322                         break;
 323                 }
 324
 325                 if (signal_pending(current)) {
 326                         retval = -ERESTARTSYS;
 327                         break;
 328                 }
 329
 330                 IRDA_DEBUG(1, "%s(%d):block_til_ready blocking on %s open_count=%d\n",
 331                       __FILE__,__LINE__, tty->driver->name, self->open_count );
 332
 333                 schedule();
 334         }
 335
 336         __set_current_state(TASK_RUNNING);
 337         remove_wait_queue(&self->open_wait, &wait);
 338
 339         if (extra_count) {
 340                 /* ++ is not atomic, so this should be protected - Jean II */
 341                 spin_lock_irqsave(&self->spinlock, flags);
 342                 self->open_count++;
 343                 spin_unlock_irqrestore(&self->spinlock, flags);
 344         }
 345         self->blocked_open--;
 346
 347         IRDA_DEBUG(1, "%s(%d):block_til_ready after blocking on %s open_count=%d\n",
 348               __FILE__,__LINE__, tty->driver->name, self->open_count);
 349
 350         if (!retval)
 351                 self->flags |= ASYNC_NORMAL_ACTIVE;
 352
 353         return retval;
 354 }
 355
 356 /*
 357  * Function ircomm_tty_open (tty, filp)
 358  *
 359  *    This routine is called when a particular tty device is opened. This
 360  *    routine is mandatory; if this routine is not filled in, the attempted
 361  *    open will fail with ENODEV.
 362  */
 363 static int ircomm_tty_open(struct tty_struct *tty, struct file *filp)
 364 {
 365         struct ircomm_tty_cb *self;
 366         unsigned int line;
 367         unsigned long   flags;
 368         int ret;
 369
 370         IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
 371
 372         line = tty->index;
 373         if ((line < 0) || (line >= IRCOMM_TTY_PORTS)) {
 374                 return -ENODEV;
 375         }
 376
 377         /* Check if instance already exists */
 378         self = hashbin_lock_find(ircomm_tty, line, NULL);
 379         if (!self) {
 380                 /* No, so make new instance */
 381                 self = kmalloc(sizeof(struct ircomm_tty_cb), GFP_KERNEL);
 382                 if (self == NULL) {
 383                         ERROR("%s(), kmalloc failed!\n", __FUNCTION__);
 384                         return -ENOMEM;
 385                 }
 386                 memset(self, 0, sizeof(struct ircomm_tty_cb));
 387
 388                 self->magic = IRCOMM_TTY_MAGIC;
 389                 self->flow = FLOW_STOP;
 390
 391                 self->line = line;
 392                 INIT_WORK(&self->tqueue, ircomm_tty_do_softint, self);
 393                 self->max_header_size = IRCOMM_TTY_HDR_UNINITIALISED;
 394                 self->max_data_size = IRCOMM_TTY_DATA_UNINITIALISED;
 395                 self->close_delay = 5*HZ/10;
 396                 self->closing_wait = 30*HZ;
 397
 398                 /* Init some important stuff */
 399                 init_timer(&self->watchdog_timer);
 400                 init_waitqueue_head(&self->open_wait);
 401                 init_waitqueue_head(&self->close_wait);
 402                 spin_lock_init(&self->spinlock);
 403
 404                 /*
 405                  * Force TTY into raw mode by default which is usually what
 406                  * we want for IrCOMM and IrLPT. This way applications will
 407                  * not have to twiddle with printcap etc.
 408                  */
 409                 tty->termios->c_iflag = 0;
 410                 tty->termios->c_oflag = 0;
 411
 412                 /* Insert into hash */
 413                 hashbin_insert(ircomm_tty, (irda_queue_t *) self, line, NULL);
 414         }
 415         /* ++ is not atomic, so this should be protected - Jean II */
 416         spin_lock_irqsave(&self->spinlock, flags);
 417         self->open_count++;
 418
 419         tty->driver_data = self;
 420         self->tty = tty;
 421         spin_unlock_irqrestore(&self->spinlock, flags);
 422
 423         IRDA_DEBUG(1, "%s(), %s%d, count = %d\n", __FUNCTION__ , tty->driver->name,
 424                    self->line, self->open_count);
 425
 426         /* Not really used by us, but lets do it anyway */
 427         self->tty->low_latency = (self->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
 428
 429         /*
 430          * If the port is the middle of closing, bail out now
 431          */
 432         if (tty_hung_up_p(filp) ||
 433             test_bit(ASYNC_B_CLOSING, &self->flags)) {
 434
 435                 /* Hm, why are we blocking on ASYNC_CLOSING if we
 436                  * do return -EAGAIN/-ERESTARTSYS below anyway?
 437                  * IMHO it's either not needed in the first place
 438                  * or for some reason we need to make sure the async
 439                  * closing has been finished - if so, wouldn't we
 440                  * probably better sleep uninterruptible?
 441                  */
 442
 443                 if (wait_event_interruptible(self->close_wait, !test_bit(ASYNC_B_CLOSING, &self->flags))) {
 444                         WARNING("%s - got signal while blocking on ASYNC_CLOSING!\n",
 445                                 __FUNCTION__);
 446                         return -ERESTARTSYS;
 447                 }
 448
 449 #ifdef SERIAL_DO_RESTART
 450                 return ((self->flags & ASYNC_HUP_NOTIFY) ?
 451                         -EAGAIN : -ERESTARTSYS);
 452 #else
 453                 return -EAGAIN;
 454 #endif
 455         }
 456
 457         /* Check if this is a "normal" ircomm device, or an irlpt device */
 458         if (line < 0x10) {
 459                 self->service_type = IRCOMM_3_WIRE | IRCOMM_9_WIRE;
 460                 self->settings.service_type = IRCOMM_9_WIRE; /* 9 wire as default */
 461                 /* Jan Kiszka -> add DSR/RI -> Conform to IrCOMM spec */
 462                 self->settings.dce = IRCOMM_CTS | IRCOMM_CD | IRCOMM_DSR | IRCOMM_RI; /* Default line settings */
 463                 IRDA_DEBUG(2, "%s(), IrCOMM device\n", __FUNCTION__ );
 464         } else {
 465                 IRDA_DEBUG(2, "%s(), IrLPT device\n", __FUNCTION__ );
 466                 self->service_type = IRCOMM_3_WIRE_RAW;
 467                 self->settings.service_type = IRCOMM_3_WIRE_RAW; /* Default */
 468         }
 469
 470         ret = ircomm_tty_startup(self);
 471         if (ret)
 472                 return ret;
 473
 474         ret = ircomm_tty_block_til_ready(self, filp);
 475         if (ret) {
 476                 IRDA_DEBUG(2,
 477                       "%s(), returning after block_til_ready with %d\n", __FUNCTION__ ,
 478                       ret);
 479
 480                 return ret;
 481         }
 482         return 0;
 483 }
 484
 485 /*
 486  * Function ircomm_tty_close (tty, filp)
 487  *
 488  *    This routine is called when a particular tty device is closed.
 489  *
 490  */
 491 static void ircomm_tty_close(struct tty_struct *tty, struct file *filp)
 492 {
 493         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
 494         unsigned long flags;
 495
 496         IRDA_DEBUG(0, "%s()\n", __FUNCTION__ );
 497
 498         if (!tty)
 499                 return;
 500
 501         ASSERT(self != NULL, return;);
 502         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
 503
 504         spin_lock_irqsave(&self->spinlock, flags);
 505
 506         if (tty_hung_up_p(filp)) {
 507                 spin_unlock_irqrestore(&self->spinlock, flags);
 508
 509                 IRDA_DEBUG(0, "%s(), returning 1\n", __FUNCTION__ );
 510                 return;
 511         }
 512
 513         if ((tty->count == 1) && (self->open_count != 1)) {
 514                 /*
 515                  * Uh, oh.  tty->count is 1, which means that the tty
 516                  * structure will be freed.  state->count should always
 517                  * be one in these conditions.  If it's greater than
 518                  * one, we've got real problems, since it means the
 519                  * serial port won't be shutdown.
 520                  */
 521                 IRDA_DEBUG(0, "%s(), bad serial port count; "
 522                            "tty->count is 1, state->count is %d\n", __FUNCTION__ ,
 523                            self->open_count);
 524                 self->open_count = 1;
 525         }
 526
 527         if (--self->open_count < 0) {
 528                 ERROR("%s(), bad serial port count for ttys%d: %d\n",
 529                       __FUNCTION__, self->line, self->open_count);
 530                 self->open_count = 0;
 531         }
 532         if (self->open_count) {
 533                 spin_unlock_irqrestore(&self->spinlock, flags);
 534
 535                 IRDA_DEBUG(0, "%s(), open count > 0\n", __FUNCTION__ );
 536                 return;
 537         }
 538
 539         /* Hum... Should be test_and_set_bit ??? - Jean II */
 540         set_bit(ASYNC_B_CLOSING, &self->flags);
 541
 542         /* We need to unlock here (we were unlocking at the end of this
 543          * function), because tty_wait_until_sent() may schedule.
 544          * I don't know if the rest should be protected somehow,
 545          * so someone should check. - Jean II */
 546         spin_unlock_irqrestore(&self->spinlock, flags);
 547
 548         /*
 549          * Now we wait for the transmit buffer to clear; and we notify
 550          * the line discipline to only process XON/XOFF characters.
 551          */
 552         tty->closing = 1;
 553         if (self->closing_wait != ASYNC_CLOSING_WAIT_NONE)
 554                 tty_wait_until_sent(tty, self->closing_wait);
 555
 556         ircomm_tty_shutdown(self);
 557
 558         if (tty->driver->flush_buffer)
 559                 tty->driver->flush_buffer(tty);
 560         if (tty->ldisc.flush_buffer)
 561                 tty->ldisc.flush_buffer(tty);
 562
 563         tty->closing = 0;
 564         self->tty = 0;
 565
 566         if (self->blocked_open) {
 567                 if (self->close_delay) {
 568                         current->state = TASK_INTERRUPTIBLE;
 569                         schedule_timeout(self->close_delay);
 570                 }
 571                 wake_up_interruptible(&self->open_wait);
 572         }
 573
 574         self->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
 575         wake_up_interruptible(&self->close_wait);
 576 }
 577
 578 /*
 579  * Function ircomm_tty_flush_buffer (tty)
 580  *
 581  *
 582  *
 583  */
 584 static void ircomm_tty_flush_buffer(struct tty_struct *tty)
 585 {
 586         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
 587
 588         ASSERT(self != NULL, return;);
 589         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
 590
 591         /*
 592          * Let do_softint() do this to avoid race condition with
 593          * do_softint() ;-)
 594          */
 595         schedule_work(&self->tqueue);
 596 }
 597
 598 /*
 599  * Function ircomm_tty_do_softint (private_)
 600  *
 601  *    We use this routine to give the write wakeup to the user at at a
 602  *    safe time (as fast as possible after write have completed). This
 603  *    can be compared to the Tx interrupt.
 604  */
 605 static void ircomm_tty_do_softint(void *private_)
 606 {
 607         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) private_;
 608         struct tty_struct *tty;
 609         unsigned long flags;
 610         struct sk_buff *skb, *ctrl_skb;
 611
 612         IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
 613
 614         if (!self || self->magic != IRCOMM_TTY_MAGIC)
 615                 return;
 616
 617         tty = self->tty;
 618         if (!tty)
 619                 return;
 620
 621         /* Unlink control buffer */
 622         spin_lock_irqsave(&self->spinlock, flags);
 623
 624         ctrl_skb = self->ctrl_skb;
 625         self->ctrl_skb = NULL;
 626
 627         spin_unlock_irqrestore(&self->spinlock, flags);
 628
 629         /* Flush control buffer if any */
 630         if(ctrl_skb) {
 631                 if(self->flow == FLOW_START)
 632                         ircomm_control_request(self->ircomm, ctrl_skb);
 633                 /* Drop reference count - see ircomm_ttp_data_request(). */
 634                 dev_kfree_skb(ctrl_skb);
 635         }
 636
 637         if (tty->hw_stopped)
 638                 return;
 639
 640         /* Unlink transmit buffer */
 641         spin_lock_irqsave(&self->spinlock, flags);
 642
 643         skb = self->tx_skb;
 644         self->tx_skb = NULL;
 645
 646         spin_unlock_irqrestore(&self->spinlock, flags);
 647
 648         /* Flush transmit buffer if any */
 649         if (skb) {
 650                 ircomm_tty_do_event(self, IRCOMM_TTY_DATA_REQUEST, skb, NULL);
 651                 /* Drop reference count - see ircomm_ttp_data_request(). */
 652                 dev_kfree_skb(skb);
 653         }
 654
 655         /* Check if user (still) wants to be waken up */
 656         if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
 657             tty->ldisc.write_wakeup)
 658         {
 659                 (tty->ldisc.write_wakeup)(tty);
 660         }
 661         wake_up_interruptible(&tty->write_wait);
 662 }
 663
 664 /*
 665  * Function ircomm_tty_write (tty, from_user, buf, count)
 666  *
 667  *    This routine is called by the kernel to write a series of characters
 668  *    to the tty device. The characters may come from user space or kernel
 669  *    space. This routine will return the number of characters actually
 670  *    accepted for writing. This routine is mandatory.
 671  */
 672 static int ircomm_tty_write(struct tty_struct *tty, int from_user,
 673                             const unsigned char *ubuf, int count)
 674 {
 675         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
 676         unsigned char *kbuf;            /* Buffer in kernel space */
 677         unsigned long flags;
 678         struct sk_buff *skb;
 679         int tailroom = 0;
 680         int len = 0;
 681         int size;
 682
 683         IRDA_DEBUG(2, "%s(), count=%d, hw_stopped=%d\n", __FUNCTION__ , count,
 684                    tty->hw_stopped);
 685
 686         ASSERT(self != NULL, return -1;);
 687         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
 688
 689         /* We may receive packets from the TTY even before we have finished
 690          * our setup. Not cool.
 691          * The problem is that we don't know the final header and data size
 692          * to create the proper skb, so any skb we would create would have
 693          * bogus header and data size, so need care.
 694          * We use a bogus header size to safely detect this condition.
 695          * Another problem is that hw_stopped was set to 0 way before it
 696          * should be, so we would drop this skb. It should now be fixed.
 697          * One option is to not accept data until we are properly setup.
 698          * But, I suspect that when it happens, the ppp line discipline
 699          * just "drops" the data, which might screw up connect scripts.
 700          * The second option is to create a "safe skb", with large header
 701          * and small size (see ircomm_tty_open() for values).
 702          * We just need to make sure that when the real values get filled,
 703          * we don't mess up the original "safe skb" (see tx_data_size).
 704          * Jean II */
 705         if (self->max_header_size == IRCOMM_TTY_HDR_UNINITIALISED) {
 706                 IRDA_DEBUG(1, "%s() : not initialised\n", __FUNCTION__);
 707 #ifdef IRCOMM_NO_TX_BEFORE_INIT
 708                 /* We didn't consume anything, TTY will retry */
 709                 return 0;
 710 #endif
 711         }
 712
 713         if (count < 1)
 714                 return 0;
 715
 716         /* Additional copy to avoid copy_from_user() under spinlock.
 717          * We tradeoff this extra copy to allow to pack more the
 718          * IrCOMM frames. This is advantageous because the IrDA link
 719          * is the bottleneck. */
 720         if (from_user) {
 721                 kbuf = kmalloc(count, GFP_KERNEL);
 722                 if (kbuf == NULL)
 723                         return -ENOMEM;
 724                 if (copy_from_user(kbuf, ubuf, count)) {
 725                         kfree(kbuf);
 726                         return -EFAULT;
 727                 }
 728         } else
 729                 /* The buffer is already in kernel space */
 730                 kbuf = (unsigned char *) ubuf;
 731
 732         /* Protect our manipulation of self->tx_skb and related */
 733         spin_lock_irqsave(&self->spinlock, flags);
 734
 735         /* Fetch current transmit buffer */
 736         skb = self->tx_skb;
 737
 738         /*
 739          * Send out all the data we get, possibly as multiple fragmented
 740          * frames, but this will only happen if the data is larger than the
 741          * max data size. The normal case however is just the opposite, and
 742          * this function may be called multiple times, and will then actually
 743          * defragment the data and send it out as one packet as soon as
 744          * possible, but at a safer point in time
 745          */
 746         while (count) {
 747                 size = count;
 748
 749                 /* Adjust data size to the max data size */
 750                 if (size > self->max_data_size)
 751                         size = self->max_data_size;
 752
 753                 /*
 754                  * Do we already have a buffer ready for transmit, or do
 755                  * we need to allocate a new frame
 756                  */
 757                 if (skb) {
 758                         /*
 759                          * Any room for more data at the end of the current
 760                          * transmit buffer? Cannot use skb_tailroom, since
 761                          * dev_alloc_skb gives us a larger skb than we
 762                          * requested
 763                          * Note : use tx_data_size, because max_data_size
 764                          * may have changed and we don't want to overwrite
 765                          * the skb. - Jean II
 766                          */
 767                         if ((tailroom = (self->tx_data_size - skb->len)) > 0) {
 768                                 /* Adjust data to tailroom */
 769                                 if (size > tailroom)
 770                                         size = tailroom;
 771                         } else {
 772                                 /*
 773                                  * Current transmit frame is full, so break
 774                                  * out, so we can send it as soon as possible
 775                                  */
 776                                 break;
 777                         }
 778                 } else {
 779                         /* Prepare a full sized frame */
 780                         skb = dev_alloc_skb(self->max_data_size+
 781                                             self->max_header_size);
 782                         if (!skb) {
 783                                 spin_unlock_irqrestore(&self->spinlock, flags);
 784                                 if (from_user)
 785                                         kfree(kbuf);
 786                                 return -ENOBUFS;
 787                         }
 788                         skb_reserve(skb, self->max_header_size);
 789                         self->tx_skb = skb;
 790                         /* Remember skb size because max_data_size may
 791                          * change later on - Jean II */
 792                         self->tx_data_size = self->max_data_size;
 793                 }
 794
 795                 /* Copy data */
 796                 memcpy(skb_put(skb,size), kbuf + len, size);
 797
 798                 count -= size;
 799                 len += size;
 800         }
 801
 802         spin_unlock_irqrestore(&self->spinlock, flags);
 803
 804         if (from_user)
 805                 kfree(kbuf);
 806
 807         /*
 808          * Schedule a new thread which will transmit the frame as soon
 809          * as possible, but at a safe point in time. We do this so the
 810          * "user" can give us data multiple times, as PPP does (because of
 811          * its 256 byte tx buffer). We will then defragment and send out
 812          * all this data as one single packet.
 813          */
 814         schedule_work(&self->tqueue);
 815
 816         return len;
 817 }
 818
 819 /*
 820  * Function ircomm_tty_write_room (tty)
 821  *
 822  *    This routine returns the numbers of characters the tty driver will
 823  *    accept for queuing to be written. This number is subject to change as
 824  *    output buffers get emptied, or if the output flow control is acted.
 825  */
 826 static int ircomm_tty_write_room(struct tty_struct *tty)
 827 {
 828         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
 829         unsigned long flags;
 830         int ret;
 831
 832         ASSERT(self != NULL, return -1;);
 833         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
 834
 835 #ifdef IRCOMM_NO_TX_BEFORE_INIT
 836         /* max_header_size tells us if the channel is initialised or not. */
 837         if (self->max_header_size == IRCOMM_TTY_HDR_UNINITIALISED)
 838                 /* Don't bother us yet */
 839                 return 0;
 840 #endif
 841
 842         /* Check if we are allowed to transmit any data.
 843          * hw_stopped is the regular flow control.
 844          * Jean II */
 845         if (tty->hw_stopped)
 846                 ret = 0;
 847         else {
 848                 spin_lock_irqsave(&self->spinlock, flags);
 849                 if (self->tx_skb)
 850                         ret = self->tx_data_size - self->tx_skb->len;
 851                 else
 852                         ret = self->max_data_size;
 853                 spin_unlock_irqrestore(&self->spinlock, flags);
 854         }
 855         IRDA_DEBUG(2, "%s(), ret=%d\n", __FUNCTION__ , ret);
 856
 857         return ret;
 858 }
 859
 860 /*
 861  * Function ircomm_tty_wait_until_sent (tty, timeout)
 862  *
 863  *    This routine waits until the device has written out all of the
 864  *    characters in its transmitter FIFO.
 865  */
 866 static void ircomm_tty_wait_until_sent(struct tty_struct *tty, int timeout)
 867 {
 868         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
 869         unsigned long orig_jiffies, poll_time;
 870         unsigned long flags;
 871
 872         IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
 873
 874         ASSERT(self != NULL, return;);
 875         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
 876
 877         orig_jiffies = jiffies;
 878
 879         /* Set poll time to 200 ms */
 880         poll_time = IRDA_MIN(timeout, msecs_to_jiffies(200));
 881
 882         spin_lock_irqsave(&self->spinlock, flags);
 883         while (self->tx_skb && self->tx_skb->len) {
 884                 spin_unlock_irqrestore(&self->spinlock, flags);
 885                 current->state = TASK_INTERRUPTIBLE;
 886                 schedule_timeout(poll_time);
 887                 spin_lock_irqsave(&self->spinlock, flags);
 888                 if (signal_pending(current))
 889                         break;
 890                 if (timeout && time_after(jiffies, orig_jiffies + timeout))
 891                         break;
 892         }
 893         spin_unlock_irqrestore(&self->spinlock, flags);
 894         current->state = TASK_RUNNING;
 895 }
 896
 897 /*
 898  * Function ircomm_tty_throttle (tty)
 899  *
 900  *    This routine notifies the tty driver that input buffers for the line
 901  *    discipline are close to full, and it should somehow signal that no
 902  *    more characters should be sent to the tty.
 903  */
 904 static void ircomm_tty_throttle(struct tty_struct *tty)
 905 {
 906         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
 907
 908         IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
 909
 910         ASSERT(self != NULL, return;);
 911         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
 912
 913         /* Software flow control? */
 914         if (I_IXOFF(tty))
 915                 ircomm_tty_send_xchar(tty, STOP_CHAR(tty));
 916
 917         /* Hardware flow control? */
 918         if (tty->termios->c_cflag & CRTSCTS) {
 919                 self->settings.dte &= ~IRCOMM_RTS;
 920                 self->settings.dte |= IRCOMM_DELTA_RTS;
 921
 922                 ircomm_param_request(self, IRCOMM_DTE, TRUE);
 923         }
 924
 925         ircomm_flow_request(self->ircomm, FLOW_STOP);
 926 }
 927
 928 /*
 929  * Function ircomm_tty_unthrottle (tty)
 930  *
 931  *    This routine notifies the tty drivers that it should signals that
 932  *    characters can now be sent to the tty without fear of overrunning the
 933  *    input buffers of the line disciplines.
 934  */
 935 static void ircomm_tty_unthrottle(struct tty_struct *tty)
 936 {
 937         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
 938
 939         IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
 940
 941         ASSERT(self != NULL, return;);
 942         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
 943
 944         /* Using software flow control? */
 945         if (I_IXOFF(tty)) {
 946                 ircomm_tty_send_xchar(tty, START_CHAR(tty));
 947         }
 948
 949         /* Using hardware flow control? */
 950         if (tty->termios->c_cflag & CRTSCTS) {
 951                 self->settings.dte |= (IRCOMM_RTS|IRCOMM_DELTA_RTS);
 952
 953                 ircomm_param_request(self, IRCOMM_DTE, TRUE);
 954                 IRDA_DEBUG(1, "%s(), FLOW_START\n", __FUNCTION__ );
 955         }
 956         ircomm_flow_request(self->ircomm, FLOW_START);
 957 }
 958
 959 /*
 960  * Function ircomm_tty_chars_in_buffer (tty)
 961  *
 962  *    Indicates if there are any data in the buffer
 963  *
 964  */
 965 static int ircomm_tty_chars_in_buffer(struct tty_struct *tty)
 966 {
 967         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
 968         unsigned long flags;
 969         int len = 0;
 970
 971         ASSERT(self != NULL, return -1;);
 972         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
 973
 974         spin_lock_irqsave(&self->spinlock, flags);
 975
 976         if (self->tx_skb)
 977                 len = self->tx_skb->len;
 978
 979         spin_unlock_irqrestore(&self->spinlock, flags);
 980
 981         return len;
 982 }
 983
 984 static void ircomm_tty_shutdown(struct ircomm_tty_cb *self)
 985 {
 986         unsigned long flags;
 987
 988         ASSERT(self != NULL, return;);
 989         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
 990
 991         IRDA_DEBUG(0, "%s()\n", __FUNCTION__ );
 992
 993         if (!test_and_clear_bit(ASYNC_B_INITIALIZED, &self->flags))
 994                 return;
 995
 996         ircomm_tty_detach_cable(self);
 997
 998         spin_lock_irqsave(&self->spinlock, flags);
 999
1000         del_timer(&self->watchdog_timer);
1001
1002         /* Free parameter buffer */
1003         if (self->ctrl_skb) {
1004                 dev_kfree_skb(self->ctrl_skb);
1005                 self->ctrl_skb = NULL;
1006         }
1007
1008         /* Free transmit buffer */
1009         if (self->tx_skb) {
1010                 dev_kfree_skb(self->tx_skb);
1011                 self->tx_skb = NULL;
1012         }
1013
1014         if (self->ircomm) {
1015                 ircomm_close(self->ircomm);
1016                 self->ircomm = NULL;
1017         }
1018
1019         spin_unlock_irqrestore(&self->spinlock, flags);
1020 }
1021
1022 /*
1023  * Function ircomm_tty_hangup (tty)
1024  *
1025  *    This routine notifies the tty driver that it should hangup the tty
1026  *    device.
1027  *
1028  */
1029 static void ircomm_tty_hangup(struct tty_struct *tty)
1030 {
1031         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
1032         unsigned long   flags;
1033
1034         IRDA_DEBUG(0, "%s()\n", __FUNCTION__ );
1035
1036         ASSERT(self != NULL, return;);
1037         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1038
1039         if (!tty)
1040                 return;
1041
1042         /* ircomm_tty_flush_buffer(tty); */
1043         ircomm_tty_shutdown(self);
1044
1045         /* I guess we need to lock here - Jean II */
1046         spin_lock_irqsave(&self->spinlock, flags);
1047         self->flags &= ~ASYNC_NORMAL_ACTIVE;
1048         self->tty = 0;
1049         self->open_count = 0;
1050         spin_unlock_irqrestore(&self->spinlock, flags);
1051
1052         wake_up_interruptible(&self->open_wait);
1053 }
1054
1055 /*
1056  * Function ircomm_tty_send_xchar (tty, ch)
1057  *
1058  *    This routine is used to send a high-priority XON/XOFF character to
1059  *    the device.
1060  */
1061 static void ircomm_tty_send_xchar(struct tty_struct *tty, char ch)
1062 {
1063         IRDA_DEBUG(0, "%s(), not impl\n", __FUNCTION__ );
1064 }
1065
1066 /*
1067  * Function ircomm_tty_start (tty)
1068  *
1069  *    This routine notifies the tty driver that it resume sending
1070  *    characters to the tty device.
1071  */
1072 void ircomm_tty_start(struct tty_struct *tty)
1073 {
1074         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
1075
1076         ircomm_flow_request(self->ircomm, FLOW_START);
1077 }
1078
1079 /*
1080  * Function ircomm_tty_stop (tty)
1081  *
1082  *     This routine notifies the tty driver that it should stop outputting
1083  *     characters to the tty device.
1084  */
1085 void ircomm_tty_stop(struct tty_struct *tty)
1086 {
1087         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) tty->driver_data;
1088
1089         ASSERT(self != NULL, return;);
1090         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1091
1092         ircomm_flow_request(self->ircomm, FLOW_STOP);
1093 }
1094
1095 /*
1096  * Function ircomm_check_modem_status (self)
1097  *
1098  *    Check for any changes in the DCE's line settings. This function should
1099  *    be called whenever the dce parameter settings changes, to update the
1100  *    flow control settings and other things
1101  */
1102 void ircomm_tty_check_modem_status(struct ircomm_tty_cb *self)
1103 {
1104         struct tty_struct *tty;
1105         int status;
1106
1107         IRDA_DEBUG(0, "%s()\n", __FUNCTION__ );
1108
1109         ASSERT(self != NULL, return;);
1110         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1111
1112         tty = self->tty;
1113
1114         status = self->settings.dce;
1115
1116         if (status & IRCOMM_DCE_DELTA_ANY) {
1117                 /*wake_up_interruptible(&self->delta_msr_wait);*/
1118         }
1119         if ((self->flags & ASYNC_CHECK_CD) && (status & IRCOMM_DELTA_CD)) {
1120                 IRDA_DEBUG(2,
1121                            "%s(), ircomm%d CD now %s...\n", __FUNCTION__ , self->line,
1122                            (status & IRCOMM_CD) ? "on" : "off");
1123
1124                 if (status & IRCOMM_CD) {
1125                         wake_up_interruptible(&self->open_wait);
1126                 } else {
1127                         IRDA_DEBUG(2,
1128                                    "%s(), Doing serial hangup..\n", __FUNCTION__ );
1129                         if (tty)
1130                                 tty_hangup(tty);
1131
1132                         /* Hangup will remote the tty, so better break out */
1133                         return;
1134                 }
1135         }
1136         if (self->flags & ASYNC_CTS_FLOW) {
1137                 if (tty->hw_stopped) {
1138                         if (status & IRCOMM_CTS) {
1139                                 IRDA_DEBUG(2,
1140                                            "%s(), CTS tx start...\n", __FUNCTION__ );
1141                                 tty->hw_stopped = 0;
1142
1143                                 /* Wake up processes blocked on open */
1144                                 wake_up_interruptible(&self->open_wait);
1145
1146                                 schedule_work(&self->tqueue);
1147                                 return;
1148                         }
1149                 } else {
1150                         if (!(status & IRCOMM_CTS)) {
1151                                 IRDA_DEBUG(2,
1152                                            "%s(), CTS tx stop...\n", __FUNCTION__ );
1153                                 tty->hw_stopped = 1;
1154                         }
1155                 }
1156         }
1157 }
1158
1159 /*
1160  * Function ircomm_tty_data_indication (instance, sap, skb)
1161  *
1162  *    Handle incoming data, and deliver it to the line discipline
1163  *
1164  */
1165 static int ircomm_tty_data_indication(void *instance, void *sap,
1166                                       struct sk_buff *skb)
1167 {
1168         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1169
1170         IRDA_DEBUG(2, "%s()\n", __FUNCTION__ );
1171
1172         ASSERT(self != NULL, return -1;);
1173         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
1174         ASSERT(skb != NULL, return -1;);
1175
1176         if (!self->tty) {
1177                 IRDA_DEBUG(0, "%s(), no tty!\n", __FUNCTION__ );
1178                 return 0;
1179         }
1180
1181         /*
1182          * If we receive data when hardware is stopped then something is wrong.
1183          * We try to poll the peers line settings to check if we are up todate.
1184          * Devices like WinCE can do this, and since they don't send any
1185          * params, we can just as well declare the hardware for running.
1186          */
1187         if (self->tty->hw_stopped && (self->flow == FLOW_START)) {
1188                 IRDA_DEBUG(0, "%s(), polling for line settings!\n", __FUNCTION__ );
1189                 ircomm_param_request(self, IRCOMM_POLL, TRUE);
1190
1191                 /* We can just as well declare the hardware for running */
1192                 ircomm_tty_send_initial_parameters(self);
1193                 ircomm_tty_link_established(self);
1194         }
1195
1196         /*
1197          * Just give it over to the line discipline. There is no need to
1198          * involve the flip buffers, since we are not running in an interrupt
1199          * handler
1200          */
1201         self->tty->ldisc.receive_buf(self->tty, skb->data, NULL, skb->len);
1202
1203         /* No need to kfree_skb - see ircomm_ttp_data_indication() */
1204
1205         return 0;
1206 }
1207
1208 /*
1209  * Function ircomm_tty_control_indication (instance, sap, skb)
1210  *
1211  *    Parse all incoming parameters (easy!)
1212  *
1213  */
1214 static int ircomm_tty_control_indication(void *instance, void *sap,
1215                                          struct sk_buff *skb)
1216 {
1217         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1218         int clen;
1219
1220         IRDA_DEBUG(4, "%s()\n", __FUNCTION__ );
1221
1222         ASSERT(self != NULL, return -1;);
1223         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return -1;);
1224         ASSERT(skb != NULL, return -1;);
1225
1226         clen = skb->data[0];
1227
1228         irda_param_extract_all(self, skb->data+1, IRDA_MIN(skb->len-1, clen),
1229                                &ircomm_param_info);
1230
1231         /* No need to kfree_skb - see ircomm_control_indication() */
1232
1233         return 0;
1234 }
1235
1236 /*
1237  * Function ircomm_tty_flow_indication (instance, sap, cmd)
1238  *
1239  *    This function is called by IrTTP when it wants us to slow down the
1240  *    transmission of data. We just mark the hardware as stopped, and wait
1241  *    for IrTTP to notify us that things are OK again.
1242  */
1243 static void ircomm_tty_flow_indication(void *instance, void *sap,
1244                                        LOCAL_FLOW cmd)
1245 {
1246         struct ircomm_tty_cb *self = (struct ircomm_tty_cb *) instance;
1247         struct tty_struct *tty;
1248
1249         ASSERT(self != NULL, return;);
1250         ASSERT(self->magic == IRCOMM_TTY_MAGIC, return;);
1251
1252         tty = self->tty;
1253
1254         switch (cmd) {
1255         case FLOW_START:
1256                 IRDA_DEBUG(2, "%s(), hw start!\n", __FUNCTION__ );
1257                 tty->hw_stopped = 0;
1258
1259                 /* ircomm_tty_do_softint will take care of the rest */
1260                 schedule_work(&self->tqueue);
1261                 break;
1262         default:  /* If we get here, something is very wrong, better stop */
1263         case FLOW_STOP:
1264                 IRDA_DEBUG(2, "%s(), hw stopped!\n", __FUNCTION__ );
1265                 tty->hw_stopped = 1;
1266                 break;
1267         }
1268         self->flow = cmd;
1269 }
1270
1271 static int ircomm_tty_line_info(struct ircomm_tty_cb *self, char *buf)
1272 {
1273         int  ret=0;
1274
1275         ret += sprintf(buf+ret, "State: %s\n", ircomm_tty_state[self->state]);
1276
1277         ret += sprintf(buf+ret, "Service type: ");
1278         if (self->service_type & IRCOMM_9_WIRE)
1279                 ret += sprintf(buf+ret, "9_WIRE");
1280         else if (self->service_type & IRCOMM_3_WIRE)
1281                 ret += sprintf(buf+ret, "3_WIRE");
1282         else if (self->service_type & IRCOMM_3_WIRE_RAW)
1283                 ret += sprintf(buf+ret, "3_WIRE_RAW");
1284         else
1285                 ret += sprintf(buf+ret, "No common service type!\n");
1286         ret += sprintf(buf+ret, "\n");
1287
1288         ret += sprintf(buf+ret, "Port name: %s\n", self->settings.port_name);
1289
1290         ret += sprintf(buf+ret, "DTE status: ");
1291         if (self->settings.dte & IRCOMM_RTS)
1292                 ret += sprintf(buf+ret, "RTS|");
1293         if (self->settings.dte & IRCOMM_DTR)
1294                 ret += sprintf(buf+ret, "DTR|");
1295         if (self->settings.dte)
1296                 ret--; /* remove the last | */
1297         ret += sprintf(buf+ret, "\n");
1298
1299         ret += sprintf(buf+ret, "DCE status: ");
1300         if (self->settings.dce & IRCOMM_CTS)
1301                 ret += sprintf(buf+ret, "CTS|");
1302         if (self->settings.dce & IRCOMM_DSR)
1303                 ret += sprintf(buf+ret, "DSR|");
1304         if (self->settings.dce & IRCOMM_CD)
1305                 ret += sprintf(buf+ret, "CD|");
1306         if (self->settings.dce & IRCOMM_RI)
1307                 ret += sprintf(buf+ret, "RI|");
1308         if (self->settings.dce)
1309                 ret--; /* remove the last | */
1310         ret += sprintf(buf+ret, "\n");
1311
1312         ret += sprintf(buf+ret, "Configuration: ");
1313         if (!self->settings.null_modem)
1314                 ret += sprintf(buf+ret, "DTE <-> DCE\n");
1315         else
1316                 ret += sprintf(buf+ret,
1317                                "DTE <-> DTE (null modem emulation)\n");
1318
1319         ret += sprintf(buf+ret, "Data rate: %d\n", self->settings.data_rate);
1320
1321         ret += sprintf(buf+ret, "Flow control: ");
1322         if (self->settings.flow_control & IRCOMM_XON_XOFF_IN)
1323                 ret += sprintf(buf+ret, "XON_XOFF_IN|");
1324         if (self->settings.flow_control & IRCOMM_XON_XOFF_OUT)
1325                 ret += sprintf(buf+ret, "XON_XOFF_OUT|");
1326         if (self->settings.flow_control & IRCOMM_RTS_CTS_IN)
1327                 ret += sprintf(buf+ret, "RTS_CTS_IN|");
1328         if (self->settings.flow_control & IRCOMM_RTS_CTS_OUT)
1329                 ret += sprintf(buf+ret, "RTS_CTS_OUT|");
1330         if (self->settings.flow_control & IRCOMM_DSR_DTR_IN)
1331                 ret += sprintf(buf+ret, "DSR_DTR_IN|");
1332         if (self->settings.flow_control & IRCOMM_DSR_DTR_OUT)
1333                 ret += sprintf(buf+ret, "DSR_DTR_OUT|");
1334         if (self->settings.flow_control & IRCOMM_ENQ_ACK_IN)
1335                 ret += sprintf(buf+ret, "ENQ_ACK_IN|");
1336         if (self->settings.flow_control & IRCOMM_ENQ_ACK_OUT)
1337                 ret += sprintf(buf+ret, "ENQ_ACK_OUT|");
1338         if (self->settings.flow_control)
1339                 ret--; /* remove the last | */
1340         ret += sprintf(buf+ret, "\n");
1341
1342         ret += sprintf(buf+ret, "Flags: ");
1343         if (self->flags & ASYNC_CTS_FLOW)
1344                 ret += sprintf(buf+ret, "ASYNC_CTS_FLOW|");
1345         if (self->flags & ASYNC_CHECK_CD)
1346                 ret += sprintf(buf+ret, "ASYNC_CHECK_CD|");
1347         if (self->flags & ASYNC_INITIALIZED)
1348                 ret += sprintf(buf+ret, "ASYNC_INITIALIZED|");
1349         if (self->flags & ASYNC_LOW_LATENCY)
1350                 ret += sprintf(buf+ret, "ASYNC_LOW_LATENCY|");
1351         if (self->flags & ASYNC_CLOSING)
1352                 ret += sprintf(buf+ret, "ASYNC_CLOSING|");
1353         if (self->flags & ASYNC_NORMAL_ACTIVE)
1354                 ret += sprintf(buf+ret, "ASYNC_NORMAL_ACTIVE|");
1355         if (self->flags)
1356                 ret--; /* remove the last | */
1357         ret += sprintf(buf+ret, "\n");
1358
1359         ret += sprintf(buf+ret, "Role: %s\n", self->client ?
1360                        "client" : "server");
1361         ret += sprintf(buf+ret, "Open count: %d\n", self->open_count);
1362         ret += sprintf(buf+ret, "Max data size: %d\n", self->max_data_size);
1363         ret += sprintf(buf+ret, "Max header size: %d\n", self->max_header_size);
1364
1365         if (self->tty)
1366                 ret += sprintf(buf+ret, "Hardware: %s\n",
1367                                self->tty->hw_stopped ? "Stopped" : "Running");
1368
1369         ret += sprintf(buf+ret, "\n");
1370         return ret;
1371 }
1372
1373
1374 /*
1375  * Function ircomm_tty_read_proc (buf, start, offset, len, eof, unused)
1376  *
1377  *
1378  *
1379  */
1380 #ifdef CONFIG_PROC_FS
1381 static int ircomm_tty_read_proc(char *buf, char **start, off_t offset, int len,
1382                                 int *eof, void *unused)
1383 {
1384         struct ircomm_tty_cb *self;
1385         int count = 0, l;
1386         off_t begin = 0;
1387         unsigned long flags;
1388
1389         spin_lock_irqsave(&ircomm_tty->hb_spinlock, flags);
1390
1391         self = (struct ircomm_tty_cb *) hashbin_get_first(ircomm_tty);
1392         while ((self != NULL) && (count < 4000)) {
1393                 if (self->magic != IRCOMM_TTY_MAGIC)
1394                         break;
1395
1396                 l = ircomm_tty_line_info(self, buf + count);
1397                 count += l;
1398                 if (count+begin > offset+len)
1399                         goto done;
1400                 if (count+begin < offset) {
1401                         begin += count;
1402                         count = 0;
1403                 }
1404
1405                 self = (struct ircomm_tty_cb *) hashbin_get_next(ircomm_tty);
1406         }
1407         *eof = 1;
1408 done:
1409         spin_unlock_irqrestore(&ircomm_tty->hb_spinlock, flags);
1410
1411         if (offset >= count+begin)
1412                 return 0;
1413         *start = buf + (offset-begin);
1414         return ((len < begin+count-offset) ? len : begin+count-offset);
1415 }
1416 #endif /* CONFIG_PROC_FS */
1417
1418 MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
1419 MODULE_DESCRIPTION("IrCOMM serial TTY driver");
1420 MODULE_LICENSE("GPL");
1421 MODULE_ALIAS_CHARDEV_MAJOR(IRCOMM_TTY_MAJOR);
1422
1423 module_init(ircomm_tty_init);
1424 module_exit(ircomm_tty_cleanup);