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