git.oblomov.eu Git - linux-2.6/blob - drivers/isdn/gigaset/interface.c

   1 /*
   2  * interface to user space for the gigaset driver
   3  *
   4  * Copyright (c) 2004 by Hansjoerg Lipp <hjlipp@web.de>
   5  *
   6  * =====================================================================
   7  *    This program is free software; you can redistribute it and/or
   8  *    modify it under the terms of the GNU General Public License as
   9  *    published by the Free Software Foundation; either version 2 of
  10  *    the License, or (at your option) any later version.
  11  * =====================================================================
  12  */
  13
  14 #include "gigaset.h"
  15 #include <linux/gigaset_dev.h>
  16 #include <linux/tty.h>
  17 #include <linux/tty_flip.h>
  18
  19 /*** our ioctls ***/
  20
  21 static int if_lock(struct cardstate *cs, int *arg)
  22 {
  23         int cmd = *arg;
  24
  25         gig_dbg(DEBUG_IF, "%u: if_lock (%d)", cs->minor_index, cmd);
  26
  27         if (cmd > 1)
  28                 return -EINVAL;
  29
  30         if (cmd < 0) {
  31                 *arg = atomic_read(&cs->mstate) == MS_LOCKED; //FIXME remove?
  32                 return 0;
  33         }
  34
  35         if (!cmd && atomic_read(&cs->mstate) == MS_LOCKED
  36             && cs->connected) {
  37                 cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
  38                 cs->ops->baud_rate(cs, B115200);
  39                 cs->ops->set_line_ctrl(cs, CS8);
  40                 cs->control_state = TIOCM_DTR|TIOCM_RTS;
  41         }
  42
  43         cs->waiting = 1;
  44         if (!gigaset_add_event(cs, &cs->at_state, EV_IF_LOCK,
  45                                NULL, cmd, NULL)) {
  46                 cs->waiting = 0;
  47                 return -ENOMEM;
  48         }
  49
  50         gig_dbg(DEBUG_CMD, "scheduling IF_LOCK");
  51         gigaset_schedule_event(cs);
  52
  53         wait_event(cs->waitqueue, !cs->waiting);
  54
  55         if (cs->cmd_result >= 0) {
  56                 *arg = cs->cmd_result;
  57                 return 0;
  58         }
  59
  60         return cs->cmd_result;
  61 }
  62
  63 static int if_version(struct cardstate *cs, unsigned arg[4])
  64 {
  65         static const unsigned version[4] = GIG_VERSION;
  66         static const unsigned compat[4] = GIG_COMPAT;
  67         unsigned cmd = arg[0];
  68
  69         gig_dbg(DEBUG_IF, "%u: if_version (%d)", cs->minor_index, cmd);
  70
  71         switch (cmd) {
  72         case GIGVER_DRIVER:
  73                 memcpy(arg, version, sizeof version);
  74                 return 0;
  75         case GIGVER_COMPAT:
  76                 memcpy(arg, compat, sizeof compat);
  77                 return 0;
  78         case GIGVER_FWBASE:
  79                 cs->waiting = 1;
  80                 if (!gigaset_add_event(cs, &cs->at_state, EV_IF_VER,
  81                                        NULL, 0, arg)) {
  82                         cs->waiting = 0;
  83                         return -ENOMEM;
  84                 }
  85
  86                 gig_dbg(DEBUG_CMD, "scheduling IF_VER");
  87                 gigaset_schedule_event(cs);
  88
  89                 wait_event(cs->waitqueue, !cs->waiting);
  90
  91                 if (cs->cmd_result >= 0)
  92                         return 0;
  93
  94                 return cs->cmd_result;
  95         default:
  96                 return -EINVAL;
  97         }
  98 }
  99
 100 static int if_config(struct cardstate *cs, int *arg)
 101 {
 102         gig_dbg(DEBUG_IF, "%u: if_config (%d)", cs->minor_index, *arg);
 103
 104         if (*arg != 1)
 105                 return -EINVAL;
 106
 107         if (atomic_read(&cs->mstate) != MS_LOCKED)
 108                 return -EBUSY;
 109
 110         if (!cs->connected) {
 111                 err("not connected!");
 112                 return -ENODEV;
 113         }
 114
 115         *arg = 0;
 116         return gigaset_enterconfigmode(cs);
 117 }
 118
 119 /*** the terminal driver ***/
 120 /* stolen from usbserial and some other tty drivers */
 121
 122 static int  if_open(struct tty_struct *tty, struct file *filp);
 123 static void if_close(struct tty_struct *tty, struct file *filp);
 124 static int  if_ioctl(struct tty_struct *tty, struct file *file,
 125                      unsigned int cmd, unsigned long arg);
 126 static int  if_write_room(struct tty_struct *tty);
 127 static int  if_chars_in_buffer(struct tty_struct *tty);
 128 static void if_throttle(struct tty_struct *tty);
 129 static void if_unthrottle(struct tty_struct *tty);
 130 static void if_set_termios(struct tty_struct *tty, struct termios *old);
 131 static int  if_tiocmget(struct tty_struct *tty, struct file *file);
 132 static int  if_tiocmset(struct tty_struct *tty, struct file *file,
 133                         unsigned int set, unsigned int clear);
 134 static int  if_write(struct tty_struct *tty,
 135                      const unsigned char *buf, int count);
 136
 137 static struct tty_operations if_ops = {
 138         .open =                 if_open,
 139         .close =                if_close,
 140         .ioctl =                if_ioctl,
 141         .write =                if_write,
 142         .write_room =           if_write_room,
 143         .chars_in_buffer =      if_chars_in_buffer,
 144         .set_termios =          if_set_termios,
 145         .throttle =             if_throttle,
 146         .unthrottle =           if_unthrottle,
 147 #if 0
 148         .break_ctl =            serial_break,
 149 #endif
 150         .tiocmget =             if_tiocmget,
 151         .tiocmset =             if_tiocmset,
 152 };
 153
 154 static int if_open(struct tty_struct *tty, struct file *filp)
 155 {
 156         struct cardstate *cs;
 157         unsigned long flags;
 158
 159         gig_dbg(DEBUG_IF, "%d+%d: %s()",
 160                 tty->driver->minor_start, tty->index, __func__);
 161
 162         tty->driver_data = NULL;
 163
 164         cs = gigaset_get_cs_by_tty(tty);
 165         if (!cs)
 166                 return -ENODEV;
 167
 168         if (mutex_lock_interruptible(&cs->mutex))
 169                 return -ERESTARTSYS; // FIXME -EINTR?
 170         tty->driver_data = cs;
 171
 172         ++cs->open_count;
 173
 174         if (cs->open_count == 1) {
 175                 spin_lock_irqsave(&cs->lock, flags);
 176                 cs->tty = tty;
 177                 spin_unlock_irqrestore(&cs->lock, flags);
 178                 tty->low_latency = 1; //FIXME test
 179         }
 180
 181         mutex_unlock(&cs->mutex);
 182         return 0;
 183 }
 184
 185 static void if_close(struct tty_struct *tty, struct file *filp)
 186 {
 187         struct cardstate *cs;
 188         unsigned long flags;
 189
 190         cs = (struct cardstate *) tty->driver_data;
 191         if (!cs) {
 192                 err("cs==NULL in %s", __func__);
 193                 return;
 194         }
 195
 196         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
 197
 198         mutex_lock(&cs->mutex);
 199
 200         if (!cs->open_count)
 201                 warn("%s: device not opened", __func__);
 202         else {
 203                 if (!--cs->open_count) {
 204                         spin_lock_irqsave(&cs->lock, flags);
 205                         cs->tty = NULL;
 206                         spin_unlock_irqrestore(&cs->lock, flags);
 207                 }
 208         }
 209
 210         mutex_unlock(&cs->mutex);
 211 }
 212
 213 static int if_ioctl(struct tty_struct *tty, struct file *file,
 214                     unsigned int cmd, unsigned long arg)
 215 {
 216         struct cardstate *cs;
 217         int retval = -ENODEV;
 218         int int_arg;
 219         unsigned char buf[6];
 220         unsigned version[4];
 221
 222         cs = (struct cardstate *) tty->driver_data;
 223         if (!cs) {
 224                 err("cs==NULL in %s", __func__);
 225                 return -ENODEV;
 226         }
 227
 228         gig_dbg(DEBUG_IF, "%u: %s(0x%x)", cs->minor_index, __func__, cmd);
 229
 230         if (mutex_lock_interruptible(&cs->mutex))
 231                 return -ERESTARTSYS; // FIXME -EINTR?
 232
 233         if (!cs->open_count)
 234                 warn("%s: device not opened", __func__);
 235         else {
 236                 retval = 0;
 237                 switch (cmd) {
 238                 case GIGASET_REDIR:
 239                         retval = get_user(int_arg, (int __user *) arg);
 240                         if (retval >= 0)
 241                                 retval = if_lock(cs, &int_arg);
 242                         if (retval >= 0)
 243                                 retval = put_user(int_arg, (int __user *) arg);
 244                         break;
 245                 case GIGASET_CONFIG:
 246                         retval = get_user(int_arg, (int __user *) arg);
 247                         if (retval >= 0)
 248                                 retval = if_config(cs, &int_arg);
 249                         if (retval >= 0)
 250                                 retval = put_user(int_arg, (int __user *) arg);
 251                         break;
 252                 case GIGASET_BRKCHARS:
 253                         //FIXME test if MS_LOCKED
 254                         if (!cs->connected) {
 255                                 gig_dbg(DEBUG_ANY,
 256                                     "can't communicate with unplugged device");
 257                                 retval = -ENODEV;
 258                                 break;
 259                         }
 260                         retval = copy_from_user(&buf,
 261                                         (const unsigned char __user *) arg, 6)
 262                                 ? -EFAULT : 0;
 263                         if (retval >= 0) {
 264                                 gigaset_dbg_buffer(DEBUG_IF, "GIGASET_BRKCHARS",
 265                                                 6, (const unsigned char *) arg);
 266                                 retval = cs->ops->brkchars(cs, buf);
 267                         }
 268                         break;
 269                 case GIGASET_VERSION:
 270                         retval = copy_from_user(version,
 271                                         (unsigned __user *) arg, sizeof version)
 272                                 ? -EFAULT : 0;
 273                         if (retval >= 0)
 274                                 retval = if_version(cs, version);
 275                         if (retval >= 0)
 276                                 retval = copy_to_user((unsigned __user *) arg,
 277                                                       version, sizeof version)
 278                                         ? -EFAULT : 0;
 279                         break;
 280                 default:
 281                         gig_dbg(DEBUG_ANY, "%s: arg not supported - 0x%04x",
 282                                 __func__, cmd);
 283                         retval = -ENOIOCTLCMD;
 284                 }
 285         }
 286
 287         mutex_unlock(&cs->mutex);
 288
 289         return retval;
 290 }
 291
 292 static int if_tiocmget(struct tty_struct *tty, struct file *file)
 293 {
 294         struct cardstate *cs;
 295         int retval;
 296
 297         cs = (struct cardstate *) tty->driver_data;
 298         if (!cs) {
 299                 err("cs==NULL in %s", __func__);
 300                 return -ENODEV;
 301         }
 302
 303         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
 304
 305         if (mutex_lock_interruptible(&cs->mutex))
 306                 return -ERESTARTSYS; // FIXME -EINTR?
 307
 308         // FIXME read from device?
 309         retval = cs->control_state & (TIOCM_RTS|TIOCM_DTR);
 310
 311         mutex_unlock(&cs->mutex);
 312
 313         return retval;
 314 }
 315
 316 static int if_tiocmset(struct tty_struct *tty, struct file *file,
 317                        unsigned int set, unsigned int clear)
 318 {
 319         struct cardstate *cs;
 320         int retval;
 321         unsigned mc;
 322
 323         cs = (struct cardstate *) tty->driver_data;
 324         if (!cs) {
 325                 err("cs==NULL in %s", __func__);
 326                 return -ENODEV;
 327         }
 328
 329         gig_dbg(DEBUG_IF, "%u: %s(0x%x, 0x%x)",
 330                 cs->minor_index, __func__, set, clear);
 331
 332         if (mutex_lock_interruptible(&cs->mutex))
 333                 return -ERESTARTSYS; // FIXME -EINTR?
 334
 335         if (!cs->connected) {
 336                 gig_dbg(DEBUG_ANY, "can't communicate with unplugged device");
 337                 retval = -ENODEV;
 338         } else {
 339                 mc = (cs->control_state | set) & ~clear & (TIOCM_RTS|TIOCM_DTR);
 340                 retval = cs->ops->set_modem_ctrl(cs, cs->control_state, mc);
 341                 cs->control_state = mc;
 342         }
 343
 344         mutex_unlock(&cs->mutex);
 345
 346         return retval;
 347 }
 348
 349 static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
 350 {
 351         struct cardstate *cs;
 352         int retval = -ENODEV;
 353
 354         cs = (struct cardstate *) tty->driver_data;
 355         if (!cs) {
 356                 err("cs==NULL in %s", __func__);
 357                 return -ENODEV;
 358         }
 359
 360         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
 361
 362         if (mutex_lock_interruptible(&cs->mutex))
 363                 return -ERESTARTSYS; // FIXME -EINTR?
 364
 365         if (!cs->open_count)
 366                 warn("%s: device not opened", __func__);
 367         else if (atomic_read(&cs->mstate) != MS_LOCKED) {
 368                 warn("can't write to unlocked device");
 369                 retval = -EBUSY;
 370         } else if (!cs->connected) {
 371                 gig_dbg(DEBUG_ANY, "can't write to unplugged device");
 372                 retval = -EBUSY; //FIXME
 373         } else {
 374                 retval = cs->ops->write_cmd(cs, buf, count,
 375                                             &cs->if_wake_tasklet);
 376         }
 377
 378         mutex_unlock(&cs->mutex);
 379
 380         return retval;
 381 }
 382
 383 static int if_write_room(struct tty_struct *tty)
 384 {
 385         struct cardstate *cs;
 386         int retval = -ENODEV;
 387
 388         cs = (struct cardstate *) tty->driver_data;
 389         if (!cs) {
 390                 err("cs==NULL in %s", __func__);
 391                 return -ENODEV;
 392         }
 393
 394         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
 395
 396         if (mutex_lock_interruptible(&cs->mutex))
 397                 return -ERESTARTSYS; // FIXME -EINTR?
 398
 399         if (!cs->open_count)
 400                 warn("%s: device not opened", __func__);
 401         else if (atomic_read(&cs->mstate) != MS_LOCKED) {
 402                 warn("can't write to unlocked device");
 403                 retval = -EBUSY; //FIXME
 404         } else if (!cs->connected) {
 405                 gig_dbg(DEBUG_ANY, "can't write to unplugged device");
 406                 retval = -EBUSY; //FIXME
 407         } else
 408                 retval = cs->ops->write_room(cs);
 409
 410         mutex_unlock(&cs->mutex);
 411
 412         return retval;
 413 }
 414
 415 static int if_chars_in_buffer(struct tty_struct *tty)
 416 {
 417         struct cardstate *cs;
 418         int retval = -ENODEV;
 419
 420         cs = (struct cardstate *) tty->driver_data;
 421         if (!cs) {
 422                 err("cs==NULL in %s", __func__);
 423                 return -ENODEV;
 424         }
 425
 426         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
 427
 428         if (mutex_lock_interruptible(&cs->mutex))
 429                 return -ERESTARTSYS; // FIXME -EINTR?
 430
 431         if (!cs->open_count)
 432                 warn("%s: device not opened", __func__);
 433         else if (atomic_read(&cs->mstate) != MS_LOCKED) {
 434                 warn("can't write to unlocked device");
 435                 retval = -EBUSY;
 436         } else if (!cs->connected) {
 437                 gig_dbg(DEBUG_ANY, "can't write to unplugged device");
 438                 retval = -EBUSY; //FIXME
 439         } else
 440                 retval = cs->ops->chars_in_buffer(cs);
 441
 442         mutex_unlock(&cs->mutex);
 443
 444         return retval;
 445 }
 446
 447 static void if_throttle(struct tty_struct *tty)
 448 {
 449         struct cardstate *cs;
 450
 451         cs = (struct cardstate *) tty->driver_data;
 452         if (!cs) {
 453                 err("cs==NULL in %s", __func__);
 454                 return;
 455         }
 456
 457         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
 458
 459         mutex_lock(&cs->mutex);
 460
 461         if (!cs->open_count)
 462                 warn("%s: device not opened", __func__);
 463         else {
 464                 //FIXME
 465         }
 466
 467         mutex_unlock(&cs->mutex);
 468 }
 469
 470 static void if_unthrottle(struct tty_struct *tty)
 471 {
 472         struct cardstate *cs;
 473
 474         cs = (struct cardstate *) tty->driver_data;
 475         if (!cs) {
 476                 err("cs==NULL in %s", __func__);
 477                 return;
 478         }
 479
 480         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
 481
 482         mutex_lock(&cs->mutex);
 483
 484         if (!cs->open_count)
 485                 warn("%s: device not opened", __func__);
 486         else {
 487                 //FIXME
 488         }
 489
 490         mutex_unlock(&cs->mutex);
 491 }
 492
 493 static void if_set_termios(struct tty_struct *tty, struct termios *old)
 494 {
 495         struct cardstate *cs;
 496         unsigned int iflag;
 497         unsigned int cflag;
 498         unsigned int old_cflag;
 499         unsigned int control_state, new_state;
 500
 501         cs = (struct cardstate *) tty->driver_data;
 502         if (!cs) {
 503                 err("cs==NULL in %s", __func__);
 504                 return;
 505         }
 506
 507         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
 508
 509         mutex_lock(&cs->mutex);
 510
 511         if (!cs->open_count) {
 512                 warn("%s: device not opened", __func__);
 513                 goto out;
 514         }
 515
 516         if (!cs->connected) {
 517                 gig_dbg(DEBUG_ANY, "can't communicate with unplugged device");
 518                 goto out;
 519         }
 520
 521         // stolen from mct_u232.c
 522         iflag = tty->termios->c_iflag;
 523         cflag = tty->termios->c_cflag;
 524         old_cflag = old ? old->c_cflag : cflag; //FIXME?
 525         gig_dbg(DEBUG_IF, "%u: iflag %x cflag %x old %x",
 526                 cs->minor_index, iflag, cflag, old_cflag);
 527
 528         /* get a local copy of the current port settings */
 529         control_state = cs->control_state;
 530
 531         /*
 532          * Update baud rate.
 533          * Do not attempt to cache old rates and skip settings,
 534          * disconnects screw such tricks up completely.
 535          * Premature optimization is the root of all evil.
 536          */
 537
 538         /* reassert DTR and (maybe) RTS on transition from B0 */
 539         if ((old_cflag & CBAUD) == B0) {
 540                 new_state = control_state | TIOCM_DTR;
 541                 /* don't set RTS if using hardware flow control */
 542                 if (!(old_cflag & CRTSCTS))
 543                         new_state |= TIOCM_RTS;
 544                 gig_dbg(DEBUG_IF, "%u: from B0 - set DTR%s",
 545                         cs->minor_index,
 546                         (new_state & TIOCM_RTS) ? " only" : "/RTS");
 547                 cs->ops->set_modem_ctrl(cs, control_state, new_state);
 548                 control_state = new_state;
 549         }
 550
 551         cs->ops->baud_rate(cs, cflag & CBAUD);
 552
 553         if ((cflag & CBAUD) == B0) {
 554                 /* Drop RTS and DTR */
 555                 gig_dbg(DEBUG_IF, "%u: to B0 - drop DTR/RTS", cs->minor_index);
 556                 new_state = control_state & ~(TIOCM_DTR | TIOCM_RTS);
 557                 cs->ops->set_modem_ctrl(cs, control_state, new_state);
 558                 control_state = new_state;
 559         }
 560
 561         /*
 562          * Update line control register (LCR)
 563          */
 564
 565         cs->ops->set_line_ctrl(cs, cflag);
 566
 567 #if 0
 568         //FIXME this hangs M101 [ts 2005-03-09]
 569         //FIXME do we need this?
 570         /*
 571          * Set flow control: well, I do not really now how to handle DTR/RTS.
 572          * Just do what we have seen with SniffUSB on Win98.
 573          */
 574         /* Drop DTR/RTS if no flow control otherwise assert */
 575         gig_dbg(DEBUG_IF, "%u: control_state %x",
 576                 cs->minor_index, control_state);
 577         new_state = control_state;
 578         if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS))
 579                 new_state |= TIOCM_DTR | TIOCM_RTS;
 580         else
 581                 new_state &= ~(TIOCM_DTR | TIOCM_RTS);
 582         if (new_state != control_state) {
 583                 gig_dbg(DEBUG_IF, "%u: new_state %x",
 584                         cs->minor_index, new_state);
 585                 gigaset_set_modem_ctrl(cs, control_state, new_state);
 586                 control_state = new_state;
 587         }
 588 #endif
 589
 590         /* save off the modified port settings */
 591         cs->control_state = control_state;
 592
 593 out:
 594         mutex_unlock(&cs->mutex);
 595 }
 596
 597
 598 /* wakeup tasklet for the write operation */
 599 static void if_wake(unsigned long data)
 600 {
 601         struct cardstate *cs = (struct cardstate *) data;
 602         struct tty_struct *tty;
 603
 604         tty = cs->tty;
 605         if (!tty)
 606                 return;
 607
 608         if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
 609             tty->ldisc.write_wakeup) {
 610                 gig_dbg(DEBUG_IF, "write wakeup call");
 611                 tty->ldisc.write_wakeup(tty);
 612         }
 613
 614         wake_up_interruptible(&tty->write_wait);
 615 }
 616
 617 /*** interface to common ***/
 618
 619 void gigaset_if_init(struct cardstate *cs)
 620 {
 621         struct gigaset_driver *drv;
 622
 623         drv = cs->driver;
 624         if (!drv->have_tty)
 625                 return;
 626
 627         tasklet_init(&cs->if_wake_tasklet, &if_wake, (unsigned long) cs);
 628         cs->class = tty_register_device(drv->tty, cs->minor_index, NULL);
 629
 630         if (!IS_ERR(cs->class))
 631                 class_set_devdata(cs->class, cs);
 632         else {
 633                 warn("could not register device to the tty subsystem");
 634                 cs->class = NULL;
 635         }
 636 }
 637
 638 void gigaset_if_free(struct cardstate *cs)
 639 {
 640         struct gigaset_driver *drv;
 641
 642         drv = cs->driver;
 643         if (!drv->have_tty)
 644                 return;
 645
 646         tasklet_disable(&cs->if_wake_tasklet);
 647         tasklet_kill(&cs->if_wake_tasklet);
 648         cs->class = NULL;
 649         tty_unregister_device(drv->tty, cs->minor_index);
 650 }
 651
 652 void gigaset_if_receive(struct cardstate *cs,
 653                         unsigned char *buffer, size_t len)
 654 {
 655         unsigned long flags;
 656         struct tty_struct *tty;
 657
 658         spin_lock_irqsave(&cs->lock, flags);
 659         if ((tty = cs->tty) == NULL)
 660                 gig_dbg(DEBUG_ANY, "receive on closed device");
 661         else {
 662                 tty_buffer_request_room(tty, len);
 663                 tty_insert_flip_string(tty, buffer, len);
 664                 tty_flip_buffer_push(tty);
 665         }
 666         spin_unlock_irqrestore(&cs->lock, flags);
 667 }
 668 EXPORT_SYMBOL_GPL(gigaset_if_receive);
 669
 670 /* gigaset_if_initdriver
 671  * Initialize tty interface.
 672  * parameters:
 673  *      drv             Driver
 674  *      procname        Name of the driver (e.g. for /proc/tty/drivers)
 675  *      devname         Name of the device files (prefix without minor number)
 676  *      devfsname       Devfs name of the device files without %d
 677  */
 678 void gigaset_if_initdriver(struct gigaset_driver *drv, const char *procname,
 679                            const char *devname, const char *devfsname)
 680 {
 681         unsigned minors = drv->minors;
 682         int ret;
 683         struct tty_driver *tty;
 684
 685         drv->have_tty = 0;
 686
 687         if ((drv->tty = alloc_tty_driver(minors)) == NULL)
 688                 goto enomem;
 689         tty = drv->tty;
 690
 691         tty->magic =            TTY_DRIVER_MAGIC,
 692         tty->major =            GIG_MAJOR,
 693         tty->type =             TTY_DRIVER_TYPE_SERIAL,
 694         tty->subtype =          SERIAL_TYPE_NORMAL,
 695         tty->flags =            TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS,
 696
 697         tty->driver_name =      procname;
 698         tty->name =             devname;
 699         tty->minor_start =      drv->minor;
 700         tty->num =              drv->minors;
 701
 702         tty->owner =            THIS_MODULE;
 703         tty->devfs_name =       devfsname;
 704
 705         tty->init_termios          = tty_std_termios; //FIXME
 706         tty->init_termios.c_cflag  = B9600 | CS8 | CREAD | HUPCL | CLOCAL; //FIXME
 707         tty_set_operations(tty, &if_ops);
 708
 709         ret = tty_register_driver(tty);
 710         if (ret < 0) {
 711                 warn("failed to register tty driver (error %d)", ret);
 712                 goto error;
 713         }
 714         gig_dbg(DEBUG_IF, "tty driver initialized");
 715         drv->have_tty = 1;
 716         return;
 717
 718 enomem:
 719         warn("could not allocate tty structures");
 720 error:
 721         if (drv->tty)
 722                 put_tty_driver(drv->tty);
 723 }
 724
 725 void gigaset_if_freedriver(struct gigaset_driver *drv)
 726 {
 727         if (!drv->have_tty)
 728                 return;
 729
 730         drv->have_tty = 0;
 731         tty_unregister_driver(drv->tty);
 732         put_tty_driver(drv->tty);
 733 }