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authorHansjoerg Lipp <hjlipp@web.de>2006-03-26 04:38:32 -0500
committerLinus Torvalds <torvalds@g5.osdl.org>2006-03-26 11:57:05 -0500
commitee8a4b7f857fe7ba243e65c8925798cf8eda5ab0 (patch)
tree8803a10dd343d13940ebfc34ce633dbacbefcd4e /drivers/isdn
parent3c66a22545dd88356bbf4efa45a7b178df8154e9 (diff)
[PATCH] isdn4linux: Siemens Gigaset drivers - tty interface
And: Tilman Schmidt <tilman@imap.cc> This patch adds the tty interface to the gigaset module. The tty interface provides direct access to the AT command set of the Gigaset devices. Signed-off-by: Hansjoerg Lipp <hjlipp@web.de> Signed-off-by: Tilman Schmidt <tilman@imap.cc> Cc: Karsten Keil <kkeil@suse.de> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/isdn')
-rw-r--r--drivers/isdn/gigaset/interface.c718
1 files changed, 718 insertions, 0 deletions
diff --git a/drivers/isdn/gigaset/interface.c b/drivers/isdn/gigaset/interface.c
new file mode 100644
index 00000000000..3a81d9c6514
--- /dev/null
+++ b/drivers/isdn/gigaset/interface.c
@@ -0,0 +1,718 @@
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 * Version: $Id: interface.c,v 1.14.4.15 2006/02/04 18:28:16 hjlipp Exp $
13 * =====================================================================
14 */
15
16#include "gigaset.h"
17#include <linux/gigaset_dev.h>
18#include <linux/tty.h>
19#include <linux/tty_flip.h>
20
21/*** our ioctls ***/
22
23static int if_lock(struct cardstate *cs, int *arg)
24{
25 int cmd = *arg;
26
27 dbg(DEBUG_IF, "%u: if_lock (%d)", cs->minor_index, cmd);
28
29 if (cmd > 1)
30 return -EINVAL;
31
32 if (cmd < 0) {
33 *arg = atomic_read(&cs->mstate) == MS_LOCKED; //FIXME remove?
34 return 0;
35 }
36
37 if (!cmd && atomic_read(&cs->mstate) == MS_LOCKED
38 && atomic_read(&cs->connected)) {
39 cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
40 cs->ops->baud_rate(cs, B115200);
41 cs->ops->set_line_ctrl(cs, CS8);
42 cs->control_state = TIOCM_DTR|TIOCM_RTS;
43 }
44
45 cs->waiting = 1;
46 if (!gigaset_add_event(cs, &cs->at_state, EV_IF_LOCK,
47 NULL, cmd, NULL)) {
48 cs->waiting = 0;
49 return -ENOMEM;
50 }
51
52 dbg(DEBUG_CMD, "scheduling IF_LOCK");
53 gigaset_schedule_event(cs);
54
55 wait_event(cs->waitqueue, !cs->waiting);
56
57 if (cs->cmd_result >= 0) {
58 *arg = cs->cmd_result;
59 return 0;
60 }
61
62 return cs->cmd_result;
63}
64
65static int if_version(struct cardstate *cs, unsigned arg[4])
66{
67 static const unsigned version[4] = GIG_VERSION;
68 static const unsigned compat[4] = GIG_COMPAT;
69 unsigned cmd = arg[0];
70
71 dbg(DEBUG_IF, "%u: if_version (%d)", cs->minor_index, cmd);
72
73 switch (cmd) {
74 case GIGVER_DRIVER:
75 memcpy(arg, version, sizeof version);
76 return 0;
77 case GIGVER_COMPAT:
78 memcpy(arg, compat, sizeof compat);
79 return 0;
80 case GIGVER_FWBASE:
81 cs->waiting = 1;
82 if (!gigaset_add_event(cs, &cs->at_state, EV_IF_VER,
83 NULL, 0, arg)) {
84 cs->waiting = 0;
85 return -ENOMEM;
86 }
87
88 dbg(DEBUG_CMD, "scheduling IF_VER");
89 gigaset_schedule_event(cs);
90
91 wait_event(cs->waitqueue, !cs->waiting);
92
93 if (cs->cmd_result >= 0)
94 return 0;
95
96 return cs->cmd_result;
97 default:
98 return -EINVAL;
99 }
100}
101
102static int if_config(struct cardstate *cs, int *arg)
103{
104 dbg(DEBUG_IF, "%u: if_config (%d)", cs->minor_index, *arg);
105
106 if (*arg != 1)
107 return -EINVAL;
108
109 if (atomic_read(&cs->mstate) != MS_LOCKED)
110 return -EBUSY;
111
112 *arg = 0;
113 return gigaset_enterconfigmode(cs);
114}
115
116/*** the terminal driver ***/
117/* stolen from usbserial and some other tty drivers */
118
119static int if_open(struct tty_struct *tty, struct file *filp);
120static void if_close(struct tty_struct *tty, struct file *filp);
121static int if_ioctl(struct tty_struct *tty, struct file *file,
122 unsigned int cmd, unsigned long arg);
123static int if_write_room(struct tty_struct *tty);
124static int if_chars_in_buffer(struct tty_struct *tty);
125static void if_throttle(struct tty_struct *tty);
126static void if_unthrottle(struct tty_struct *tty);
127static void if_set_termios(struct tty_struct *tty, struct termios *old);
128static int if_tiocmget(struct tty_struct *tty, struct file *file);
129static int if_tiocmset(struct tty_struct *tty, struct file *file,
130 unsigned int set, unsigned int clear);
131static int if_write(struct tty_struct *tty,
132 const unsigned char *buf, int count);
133
134static struct tty_operations if_ops = {
135 .open = if_open,
136 .close = if_close,
137 .ioctl = if_ioctl,
138 .write = if_write,
139 .write_room = if_write_room,
140 .chars_in_buffer = if_chars_in_buffer,
141 .set_termios = if_set_termios,
142 .throttle = if_throttle,
143 .unthrottle = if_unthrottle,
144#if 0
145 .break_ctl = serial_break,
146#endif
147 .tiocmget = if_tiocmget,
148 .tiocmset = if_tiocmset,
149};
150
151static int if_open(struct tty_struct *tty, struct file *filp)
152{
153 struct cardstate *cs;
154 unsigned long flags;
155
156 dbg(DEBUG_IF, "%d+%d: %s()", tty->driver->minor_start, tty->index,
157 __FUNCTION__);
158
159 tty->driver_data = NULL;
160
161 cs = gigaset_get_cs_by_tty(tty);
162 if (!cs)
163 return -ENODEV;
164
165 if (down_interruptible(&cs->sem))
166 return -ERESTARTSYS; // FIXME -EINTR?
167 tty->driver_data = cs;
168
169 ++cs->open_count;
170
171 if (cs->open_count == 1) {
172 spin_lock_irqsave(&cs->lock, flags);
173 cs->tty = tty;
174 spin_unlock_irqrestore(&cs->lock, flags);
175 tty->low_latency = 1; //FIXME test
176 //FIXME
177 }
178
179 up(&cs->sem);
180 return 0;
181}
182
183static void if_close(struct tty_struct *tty, struct file *filp)
184{
185 struct cardstate *cs;
186 unsigned long flags;
187
188 cs = (struct cardstate *) tty->driver_data;
189 if (!cs) {
190 err("cs==NULL in %s", __FUNCTION__);
191 return;
192 }
193
194 dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __FUNCTION__);
195
196 down(&cs->sem);
197
198 if (!cs->open_count)
199 warn("%s: device not opened", __FUNCTION__);
200 else {
201 if (!--cs->open_count) {
202 spin_lock_irqsave(&cs->lock, flags);
203 cs->tty = NULL;
204 spin_unlock_irqrestore(&cs->lock, flags);
205 //FIXME
206 }
207 }
208
209 up(&cs->sem);
210}
211
212static int if_ioctl(struct tty_struct *tty, struct file *file,
213 unsigned int cmd, unsigned long arg)
214{
215 struct cardstate *cs;
216 int retval = -ENODEV;
217 int int_arg;
218 unsigned char buf[6];
219 unsigned version[4];
220
221 cs = (struct cardstate *) tty->driver_data;
222 if (!cs) {
223 err("cs==NULL in %s", __FUNCTION__);
224 return -ENODEV;
225 }
226
227 dbg(DEBUG_IF, "%u: %s(0x%x)", cs->minor_index, __FUNCTION__, cmd);
228
229 if (down_interruptible(&cs->sem))
230 return -ERESTARTSYS; // FIXME -EINTR?
231
232 if (!cs->open_count)
233 warn("%s: device not opened", __FUNCTION__);
234 else {
235 retval = 0;
236 switch (cmd) {
237 case GIGASET_REDIR:
238 retval = get_user(int_arg, (int __user *) arg);
239 if (retval >= 0)
240 retval = if_lock(cs, &int_arg);
241 if (retval >= 0)
242 retval = put_user(int_arg, (int __user *) arg);
243 break;
244 case GIGASET_CONFIG:
245 retval = get_user(int_arg, (int __user *) arg);
246 if (retval >= 0)
247 retval = if_config(cs, &int_arg);
248 if (retval >= 0)
249 retval = put_user(int_arg, (int __user *) arg);
250 break;
251 case GIGASET_BRKCHARS:
252 //FIXME test if MS_LOCKED
253 gigaset_dbg_buffer(DEBUG_IF, "GIGASET_BRKCHARS",
254 6, (const unsigned char *) arg, 1);
255 if (!atomic_read(&cs->connected)) {
256 dbg(DEBUG_ANY, "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 retval = cs->ops->brkchars(cs, buf);
265 break;
266 case GIGASET_VERSION:
267 retval = copy_from_user(version, (unsigned __user *) arg,
268 sizeof version) ? -EFAULT : 0;
269 if (retval >= 0)
270 retval = if_version(cs, version);
271 if (retval >= 0)
272 retval = copy_to_user((unsigned __user *) arg, version,
273 sizeof version)
274 ? -EFAULT : 0;
275 break;
276 default:
277 dbg(DEBUG_ANY, "%s: arg not supported - 0x%04x",
278 __FUNCTION__, cmd);
279 retval = -ENOIOCTLCMD;
280 }
281 }
282
283 up(&cs->sem);
284
285 return retval;
286}
287
288static int if_tiocmget(struct tty_struct *tty, struct file *file)
289{
290 struct cardstate *cs;
291 int retval;
292
293 cs = (struct cardstate *) tty->driver_data;
294 if (!cs) {
295 err("cs==NULL in %s", __FUNCTION__);
296 return -ENODEV;
297 }
298
299 dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __FUNCTION__);
300
301 if (down_interruptible(&cs->sem))
302 return -ERESTARTSYS; // FIXME -EINTR?
303
304 // FIXME read from device?
305 retval = cs->control_state & (TIOCM_RTS|TIOCM_DTR);
306
307 up(&cs->sem);
308
309 return retval;
310}
311
312static int if_tiocmset(struct tty_struct *tty, struct file *file,
313 unsigned int set, unsigned int clear)
314{
315 struct cardstate *cs;
316 int retval;
317 unsigned mc;
318
319 cs = (struct cardstate *) tty->driver_data;
320 if (!cs) {
321 err("cs==NULL in %s", __FUNCTION__);
322 return -ENODEV;
323 }
324
325 dbg(DEBUG_IF,
326 "%u: %s(0x%x, 0x%x)", cs->minor_index, __FUNCTION__, set, clear);
327
328 if (down_interruptible(&cs->sem))
329 return -ERESTARTSYS; // FIXME -EINTR?
330
331 if (!atomic_read(&cs->connected)) {
332 dbg(DEBUG_ANY, "can't communicate with unplugged device");
333 retval = -ENODEV;
334 } else {
335 mc = (cs->control_state | set) & ~clear & (TIOCM_RTS|TIOCM_DTR);
336 retval = cs->ops->set_modem_ctrl(cs, cs->control_state, mc);
337 cs->control_state = mc;
338 }
339
340 up(&cs->sem);
341
342 return retval;
343}
344
345static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
346{
347 struct cardstate *cs;
348 int retval = -ENODEV;
349
350 cs = (struct cardstate *) tty->driver_data;
351 if (!cs) {
352 err("cs==NULL in %s", __FUNCTION__);
353 return -ENODEV;
354 }
355
356 dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __FUNCTION__);
357
358 if (down_interruptible(&cs->sem))
359 return -ERESTARTSYS; // FIXME -EINTR?
360
361 if (!cs->open_count)
362 warn("%s: device not opened", __FUNCTION__);
363 else if (atomic_read(&cs->mstate) != MS_LOCKED) {
364 warn("can't write to unlocked device");
365 retval = -EBUSY;
366 } else if (!atomic_read(&cs->connected)) {
367 dbg(DEBUG_ANY, "can't write to unplugged device");
368 retval = -EBUSY; //FIXME
369 } else {
370 retval = cs->ops->write_cmd(cs, buf, count,
371 &cs->if_wake_tasklet);
372 }
373
374 up(&cs->sem);
375
376 return retval;
377}
378
379static int if_write_room(struct tty_struct *tty)
380{
381 struct cardstate *cs;
382 int retval = -ENODEV;
383
384 cs = (struct cardstate *) tty->driver_data;
385 if (!cs) {
386 err("cs==NULL in %s", __FUNCTION__);
387 return -ENODEV;
388 }
389
390 dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __FUNCTION__);
391
392 if (down_interruptible(&cs->sem))
393 return -ERESTARTSYS; // FIXME -EINTR?
394
395 if (!cs->open_count)
396 warn("%s: device not opened", __FUNCTION__);
397 else if (atomic_read(&cs->mstate) != MS_LOCKED) {
398 warn("can't write to unlocked device");
399 retval = -EBUSY; //FIXME
400 } else if (!atomic_read(&cs->connected)) {
401 dbg(DEBUG_ANY, "can't write to unplugged device");
402 retval = -EBUSY; //FIXME
403 } else
404 retval = cs->ops->write_room(cs);
405
406 up(&cs->sem);
407
408 return retval;
409}
410
411static int if_chars_in_buffer(struct tty_struct *tty)
412{
413 struct cardstate *cs;
414 int retval = -ENODEV;
415
416 cs = (struct cardstate *) tty->driver_data;
417 if (!cs) {
418 err("cs==NULL in %s", __FUNCTION__);
419 return -ENODEV;
420 }
421
422 dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __FUNCTION__);
423
424 if (down_interruptible(&cs->sem))
425 return -ERESTARTSYS; // FIXME -EINTR?
426
427 if (!cs->open_count)
428 warn("%s: device not opened", __FUNCTION__);
429 else if (atomic_read(&cs->mstate) != MS_LOCKED) {
430 warn("can't write to unlocked device");
431 retval = -EBUSY;
432 } else if (!atomic_read(&cs->connected)) {
433 dbg(DEBUG_ANY, "can't write to unplugged device");
434 retval = -EBUSY; //FIXME
435 } else
436 retval = cs->ops->chars_in_buffer(cs);
437
438 up(&cs->sem);
439
440 return retval;
441}
442
443static void if_throttle(struct tty_struct *tty)
444{
445 struct cardstate *cs;
446
447 cs = (struct cardstate *) tty->driver_data;
448 if (!cs) {
449 err("cs==NULL in %s", __FUNCTION__);
450 return;
451 }
452
453 dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __FUNCTION__);
454
455 down(&cs->sem);
456
457 if (!cs->open_count)
458 warn("%s: device not opened", __FUNCTION__);
459 else {
460 //FIXME
461 }
462
463 up(&cs->sem);
464}
465
466static void if_unthrottle(struct tty_struct *tty)
467{
468 struct cardstate *cs;
469
470 cs = (struct cardstate *) tty->driver_data;
471 if (!cs) {
472 err("cs==NULL in %s", __FUNCTION__);
473 return;
474 }
475
476 dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __FUNCTION__);
477
478 down(&cs->sem);
479
480 if (!cs->open_count)
481 warn("%s: device not opened", __FUNCTION__);
482 else {
483 //FIXME
484 }
485
486 up(&cs->sem);
487}
488
489static void if_set_termios(struct tty_struct *tty, struct termios *old)
490{
491 struct cardstate *cs;
492 unsigned int iflag;
493 unsigned int cflag;
494 unsigned int old_cflag;
495 unsigned int control_state, new_state;
496
497 cs = (struct cardstate *) tty->driver_data;
498 if (!cs) {
499 err("cs==NULL in %s", __FUNCTION__);
500 return;
501 }
502
503 dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __FUNCTION__);
504
505 down(&cs->sem);
506
507 if (!cs->open_count) {
508 warn("%s: device not opened", __FUNCTION__);
509 goto out;
510 }
511
512 if (!atomic_read(&cs->connected)) {
513 dbg(DEBUG_ANY, "can't communicate with unplugged device");
514 goto out;
515 }
516
517 // stolen from mct_u232.c
518 iflag = tty->termios->c_iflag;
519 cflag = tty->termios->c_cflag;
520 old_cflag = old ? old->c_cflag : cflag; //FIXME?
521 dbg(DEBUG_IF, "%u: iflag %x cflag %x old %x", cs->minor_index,
522 iflag, cflag, old_cflag);
523
524 /* get a local copy of the current port settings */
525 control_state = cs->control_state;
526
527 /*
528 * Update baud rate.
529 * Do not attempt to cache old rates and skip settings,
530 * disconnects screw such tricks up completely.
531 * Premature optimization is the root of all evil.
532 */
533
534 /* reassert DTR and (maybe) RTS on transition from B0 */
535 if ((old_cflag & CBAUD) == B0) {
536 new_state = control_state | TIOCM_DTR;
537 /* don't set RTS if using hardware flow control */
538 if (!(old_cflag & CRTSCTS))
539 new_state |= TIOCM_RTS;
540 dbg(DEBUG_IF, "%u: from B0 - set DTR%s", cs->minor_index,
541 (new_state & TIOCM_RTS) ? " only" : "/RTS");
542 cs->ops->set_modem_ctrl(cs, control_state, new_state);
543 control_state = new_state;
544 }
545
546 cs->ops->baud_rate(cs, cflag & CBAUD);
547
548 if ((cflag & CBAUD) == B0) {
549 /* Drop RTS and DTR */
550 dbg(DEBUG_IF, "%u: to B0 - drop DTR/RTS", cs->minor_index);
551 new_state = control_state & ~(TIOCM_DTR | TIOCM_RTS);
552 cs->ops->set_modem_ctrl(cs, control_state, new_state);
553 control_state = new_state;
554 }
555
556 /*
557 * Update line control register (LCR)
558 */
559
560 cs->ops->set_line_ctrl(cs, cflag);
561
562#if 0
563 //FIXME this hangs M101 [ts 2005-03-09]
564 //FIXME do we need this?
565 /*
566 * Set flow control: well, I do not really now how to handle DTR/RTS.
567 * Just do what we have seen with SniffUSB on Win98.
568 */
569 /* Drop DTR/RTS if no flow control otherwise assert */
570 dbg(DEBUG_IF, "%u: control_state %x", cs->minor_index, control_state);
571 new_state = control_state;
572 if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS))
573 new_state |= TIOCM_DTR | TIOCM_RTS;
574 else
575 new_state &= ~(TIOCM_DTR | TIOCM_RTS);
576 if (new_state != control_state) {
577 dbg(DEBUG_IF, "%u: new_state %x", cs->minor_index, new_state);
578 gigaset_set_modem_ctrl(cs, control_state, new_state); // FIXME: mct_u232.c sets the old state here. is this a bug?
579 control_state = new_state;
580 }
581#endif
582
583 /* save off the modified port settings */
584 cs->control_state = control_state;
585
586out:
587 up(&cs->sem);
588}
589
590
591/* wakeup tasklet for the write operation */
592static void if_wake(unsigned long data)
593{
594 struct cardstate *cs = (struct cardstate *) data;
595 struct tty_struct *tty;
596
597 tty = cs->tty;
598 if (!tty)
599 return;
600
601 if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) &&
602 tty->ldisc.write_wakeup) {
603 dbg(DEBUG_IF, "write wakeup call");
604 tty->ldisc.write_wakeup(tty);
605 }
606
607 wake_up_interruptible(&tty->write_wait);
608}
609
610/*** interface to common ***/
611
612void gigaset_if_init(struct cardstate *cs)
613{
614 struct gigaset_driver *drv;
615
616 drv = cs->driver;
617 if (!drv->have_tty)
618 return;
619
620 tasklet_init(&cs->if_wake_tasklet, &if_wake, (unsigned long) cs);
621 tty_register_device(drv->tty, cs->minor_index, NULL);
622}
623
624void gigaset_if_free(struct cardstate *cs)
625{
626 struct gigaset_driver *drv;
627
628 drv = cs->driver;
629 if (!drv->have_tty)
630 return;
631
632 tasklet_disable(&cs->if_wake_tasklet);
633 tasklet_kill(&cs->if_wake_tasklet);
634 tty_unregister_device(drv->tty, cs->minor_index);
635}
636
637void gigaset_if_receive(struct cardstate *cs,
638 unsigned char *buffer, size_t len)
639{
640 unsigned long flags;
641 struct tty_struct *tty;
642
643 spin_lock_irqsave(&cs->lock, flags);
644 if ((tty = cs->tty) == NULL)
645 dbg(DEBUG_ANY, "receive on closed device");
646 else {
647 tty_buffer_request_room(tty, len);
648 tty_insert_flip_string(tty, buffer, len);
649 tty_flip_buffer_push(tty);
650 }
651 spin_unlock_irqrestore(&cs->lock, flags);
652}
653EXPORT_SYMBOL_GPL(gigaset_if_receive);
654
655/* gigaset_if_initdriver
656 * Initialize tty interface.
657 * parameters:
658 * drv Driver
659 * procname Name of the driver (e.g. for /proc/tty/drivers)
660 * devname Name of the device files (prefix without minor number)
661 * devfsname Devfs name of the device files without %d
662 */
663void gigaset_if_initdriver(struct gigaset_driver *drv, const char *procname,
664 const char *devname, const char *devfsname)
665{
666 unsigned minors = drv->minors;
667 int ret;
668 struct tty_driver *tty;
669
670 drv->have_tty = 0;
671
672 if ((drv->tty = alloc_tty_driver(minors)) == NULL)
673 goto enomem;
674 tty = drv->tty;
675
676 tty->magic = TTY_DRIVER_MAGIC,
677 tty->major = GIG_MAJOR,
678 tty->type = TTY_DRIVER_TYPE_SERIAL,
679 tty->subtype = SERIAL_TYPE_NORMAL,
680 tty->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS,
681
682 tty->driver_name = procname;
683 tty->name = devname;
684 tty->minor_start = drv->minor;
685 tty->num = drv->minors;
686
687 tty->owner = THIS_MODULE;
688 tty->devfs_name = devfsname;
689
690 tty->init_termios = tty_std_termios; //FIXME
691 tty->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL; //FIXME
692 tty_set_operations(tty, &if_ops);
693
694 ret = tty_register_driver(tty);
695 if (ret < 0) {
696 warn("failed to register tty driver (error %d)", ret);
697 goto error;
698 }
699 dbg(DEBUG_IF, "tty driver initialized");
700 drv->have_tty = 1;
701 return;
702
703enomem:
704 warn("could not allocate tty structures");
705error:
706 if (drv->tty)
707 put_tty_driver(drv->tty);
708}
709
710void gigaset_if_freedriver(struct gigaset_driver *drv)
711{
712 if (!drv->have_tty)
713 return;
714
715 drv->have_tty = 0;
716 tty_unregister_driver(drv->tty);
717 put_tty_driver(drv->tty);
718}