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