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