Merge branch 'for-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq
[linux-2.6.git] / 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_flip.h>
17 #include <linux/module.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         gigaset_schedule_event(cs);
49
50         wait_event(cs->waitqueue, !cs->waiting);
51
52         if (cs->cmd_result >= 0) {
53                 *arg = cs->cmd_result;
54                 return 0;
55         }
56
57         return cs->cmd_result;
58 }
59
60 static int if_version(struct cardstate *cs, unsigned arg[4])
61 {
62         static const unsigned version[4] = GIG_VERSION;
63         static const unsigned compat[4] = GIG_COMPAT;
64         unsigned cmd = arg[0];
65
66         gig_dbg(DEBUG_IF, "%u: if_version (%d)", cs->minor_index, cmd);
67
68         switch (cmd) {
69         case GIGVER_DRIVER:
70                 memcpy(arg, version, sizeof version);
71                 return 0;
72         case GIGVER_COMPAT:
73                 memcpy(arg, compat, sizeof compat);
74                 return 0;
75         case GIGVER_FWBASE:
76                 cs->waiting = 1;
77                 if (!gigaset_add_event(cs, &cs->at_state, EV_IF_VER,
78                                        NULL, 0, arg)) {
79                         cs->waiting = 0;
80                         return -ENOMEM;
81                 }
82                 gigaset_schedule_event(cs);
83
84                 wait_event(cs->waitqueue, !cs->waiting);
85
86                 if (cs->cmd_result >= 0)
87                         return 0;
88
89                 return cs->cmd_result;
90         default:
91                 return -EINVAL;
92         }
93 }
94
95 static int if_config(struct cardstate *cs, int *arg)
96 {
97         gig_dbg(DEBUG_IF, "%u: if_config (%d)", cs->minor_index, *arg);
98
99         if (*arg != 1)
100                 return -EINVAL;
101
102         if (cs->mstate != MS_LOCKED)
103                 return -EBUSY;
104
105         if (!cs->connected) {
106                 pr_err("%s: not connected\n", __func__);
107                 return -ENODEV;
108         }
109
110         *arg = 0;
111         return gigaset_enterconfigmode(cs);
112 }
113
114 /*** the terminal driver ***/
115 /* stolen from usbserial and some other tty drivers */
116
117 static int  if_open(struct tty_struct *tty, struct file *filp);
118 static void if_close(struct tty_struct *tty, struct file *filp);
119 static int  if_ioctl(struct tty_struct *tty,
120                      unsigned int cmd, unsigned long arg);
121 static int  if_write_room(struct tty_struct *tty);
122 static int  if_chars_in_buffer(struct tty_struct *tty);
123 static void if_throttle(struct tty_struct *tty);
124 static void if_unthrottle(struct tty_struct *tty);
125 static void if_set_termios(struct tty_struct *tty, struct ktermios *old);
126 static int  if_tiocmget(struct tty_struct *tty);
127 static int  if_tiocmset(struct tty_struct *tty,
128                         unsigned int set, unsigned int clear);
129 static int  if_write(struct tty_struct *tty,
130                      const unsigned char *buf, int count);
131
132 static const struct tty_operations if_ops = {
133         .open =                 if_open,
134         .close =                if_close,
135         .ioctl =                if_ioctl,
136         .write =                if_write,
137         .write_room =           if_write_room,
138         .chars_in_buffer =      if_chars_in_buffer,
139         .set_termios =          if_set_termios,
140         .throttle =             if_throttle,
141         .unthrottle =           if_unthrottle,
142         .tiocmget =             if_tiocmget,
143         .tiocmset =             if_tiocmset,
144 };
145
146 static int if_open(struct tty_struct *tty, struct file *filp)
147 {
148         struct cardstate *cs;
149
150         gig_dbg(DEBUG_IF, "%d+%d: %s()",
151                 tty->driver->minor_start, tty->index, __func__);
152
153         cs = gigaset_get_cs_by_tty(tty);
154         if (!cs || !try_module_get(cs->driver->owner))
155                 return -ENODEV;
156
157         if (mutex_lock_interruptible(&cs->mutex)) {
158                 module_put(cs->driver->owner);
159                 return -ERESTARTSYS;
160         }
161         tty->driver_data = cs;
162
163         ++cs->port.count;
164
165         if (cs->port.count == 1) {
166                 tty_port_tty_set(&cs->port, tty);
167                 tty->low_latency = 1;
168         }
169
170         mutex_unlock(&cs->mutex);
171         return 0;
172 }
173
174 static void if_close(struct tty_struct *tty, struct file *filp)
175 {
176         struct cardstate *cs = tty->driver_data;
177
178         if (!cs) { /* happens if we didn't find cs in open */
179                 printk(KERN_DEBUG "%s: no cardstate\n", __func__);
180                 return;
181         }
182
183         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
184
185         mutex_lock(&cs->mutex);
186
187         if (!cs->connected)
188                 gig_dbg(DEBUG_IF, "not connected");     /* nothing to do */
189         else if (!cs->port.count)
190                 dev_warn(cs->dev, "%s: device not opened\n", __func__);
191         else if (!--cs->port.count)
192                 tty_port_tty_set(&cs->port, NULL);
193
194         mutex_unlock(&cs->mutex);
195
196         module_put(cs->driver->owner);
197 }
198
199 static int if_ioctl(struct tty_struct *tty,
200                     unsigned int cmd, unsigned long arg)
201 {
202         struct cardstate *cs = tty->driver_data;
203         int retval = -ENODEV;
204         int int_arg;
205         unsigned char buf[6];
206         unsigned version[4];
207
208         gig_dbg(DEBUG_IF, "%u: %s(0x%x)", cs->minor_index, __func__, cmd);
209
210         if (mutex_lock_interruptible(&cs->mutex))
211                 return -ERESTARTSYS;
212
213         if (!cs->connected) {
214                 gig_dbg(DEBUG_IF, "not connected");
215                 retval = -ENODEV;
216         } else {
217                 retval = 0;
218                 switch (cmd) {
219                 case GIGASET_REDIR:
220                         retval = get_user(int_arg, (int __user *) arg);
221                         if (retval >= 0)
222                                 retval = if_lock(cs, &int_arg);
223                         if (retval >= 0)
224                                 retval = put_user(int_arg, (int __user *) arg);
225                         break;
226                 case GIGASET_CONFIG:
227                         retval = get_user(int_arg, (int __user *) arg);
228                         if (retval >= 0)
229                                 retval = if_config(cs, &int_arg);
230                         if (retval >= 0)
231                                 retval = put_user(int_arg, (int __user *) arg);
232                         break;
233                 case GIGASET_BRKCHARS:
234                         retval = copy_from_user(&buf,
235                                         (const unsigned char __user *) arg, 6)
236                                 ? -EFAULT : 0;
237                         if (retval >= 0) {
238                                 gigaset_dbg_buffer(DEBUG_IF, "GIGASET_BRKCHARS",
239                                                 6, (const unsigned char *) arg);
240                                 retval = cs->ops->brkchars(cs, buf);
241                         }
242                         break;
243                 case GIGASET_VERSION:
244                         retval = copy_from_user(version,
245                                         (unsigned __user *) arg, sizeof version)
246                                 ? -EFAULT : 0;
247                         if (retval >= 0)
248                                 retval = if_version(cs, version);
249                         if (retval >= 0)
250                                 retval = copy_to_user((unsigned __user *) arg,
251                                                       version, sizeof version)
252                                         ? -EFAULT : 0;
253                         break;
254                 default:
255                         gig_dbg(DEBUG_IF, "%s: arg not supported - 0x%04x",
256                                 __func__, cmd);
257                         retval = -ENOIOCTLCMD;
258                 }
259         }
260
261         mutex_unlock(&cs->mutex);
262
263         return retval;
264 }
265
266 static int if_tiocmget(struct tty_struct *tty)
267 {
268         struct cardstate *cs = tty->driver_data;
269         int retval;
270
271         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
272
273         if (mutex_lock_interruptible(&cs->mutex))
274                 return -ERESTARTSYS;
275
276         retval = cs->control_state & (TIOCM_RTS|TIOCM_DTR);
277
278         mutex_unlock(&cs->mutex);
279
280         return retval;
281 }
282
283 static int if_tiocmset(struct tty_struct *tty,
284                        unsigned int set, unsigned int clear)
285 {
286         struct cardstate *cs = tty->driver_data;
287         int retval;
288         unsigned mc;
289
290         gig_dbg(DEBUG_IF, "%u: %s(0x%x, 0x%x)",
291                 cs->minor_index, __func__, set, clear);
292
293         if (mutex_lock_interruptible(&cs->mutex))
294                 return -ERESTARTSYS;
295
296         if (!cs->connected) {
297                 gig_dbg(DEBUG_IF, "not connected");
298                 retval = -ENODEV;
299         } else {
300                 mc = (cs->control_state | set) & ~clear & (TIOCM_RTS|TIOCM_DTR);
301                 retval = cs->ops->set_modem_ctrl(cs, cs->control_state, mc);
302                 cs->control_state = mc;
303         }
304
305         mutex_unlock(&cs->mutex);
306
307         return retval;
308 }
309
310 static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
311 {
312         struct cardstate *cs = tty->driver_data;
313         struct cmdbuf_t *cb;
314         int retval;
315
316         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
317
318         if (mutex_lock_interruptible(&cs->mutex))
319                 return -ERESTARTSYS;
320
321         if (!cs->connected) {
322                 gig_dbg(DEBUG_IF, "not connected");
323                 retval = -ENODEV;
324                 goto done;
325         }
326         if (cs->mstate != MS_LOCKED) {
327                 dev_warn(cs->dev, "can't write to unlocked device\n");
328                 retval = -EBUSY;
329                 goto done;
330         }
331         if (count <= 0) {
332                 /* nothing to do */
333                 retval = 0;
334                 goto done;
335         }
336
337         cb = kmalloc(sizeof(struct cmdbuf_t) + count, GFP_KERNEL);
338         if (!cb) {
339                 dev_err(cs->dev, "%s: out of memory\n", __func__);
340                 retval = -ENOMEM;
341                 goto done;
342         }
343
344         memcpy(cb->buf, buf, count);
345         cb->len = count;
346         cb->offset = 0;
347         cb->next = NULL;
348         cb->wake_tasklet = &cs->if_wake_tasklet;
349         retval = cs->ops->write_cmd(cs, cb);
350 done:
351         mutex_unlock(&cs->mutex);
352         return retval;
353 }
354
355 static int if_write_room(struct tty_struct *tty)
356 {
357         struct cardstate *cs = tty->driver_data;
358         int retval = -ENODEV;
359
360         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
361
362         if (mutex_lock_interruptible(&cs->mutex))
363                 return -ERESTARTSYS;
364
365         if (!cs->connected) {
366                 gig_dbg(DEBUG_IF, "not connected");
367                 retval = -ENODEV;
368         } else if (cs->mstate != MS_LOCKED) {
369                 dev_warn(cs->dev, "can't write to unlocked device\n");
370                 retval = -EBUSY;
371         } else
372                 retval = cs->ops->write_room(cs);
373
374         mutex_unlock(&cs->mutex);
375
376         return retval;
377 }
378
379 static int if_chars_in_buffer(struct tty_struct *tty)
380 {
381         struct cardstate *cs = tty->driver_data;
382         int retval = 0;
383
384         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
385
386         mutex_lock(&cs->mutex);
387
388         if (!cs->connected)
389                 gig_dbg(DEBUG_IF, "not connected");
390         else if (cs->mstate != MS_LOCKED)
391                 dev_warn(cs->dev, "can't write to unlocked device\n");
392         else
393                 retval = cs->ops->chars_in_buffer(cs);
394
395         mutex_unlock(&cs->mutex);
396
397         return retval;
398 }
399
400 static void if_throttle(struct tty_struct *tty)
401 {
402         struct cardstate *cs = tty->driver_data;
403
404         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
405
406         mutex_lock(&cs->mutex);
407
408         if (!cs->connected)
409                 gig_dbg(DEBUG_IF, "not connected");     /* nothing to do */
410         else
411                 gig_dbg(DEBUG_IF, "%s: not implemented\n", __func__);
412
413         mutex_unlock(&cs->mutex);
414 }
415
416 static void if_unthrottle(struct tty_struct *tty)
417 {
418         struct cardstate *cs = tty->driver_data;
419
420         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
421
422         mutex_lock(&cs->mutex);
423
424         if (!cs->connected)
425                 gig_dbg(DEBUG_IF, "not connected");     /* nothing to do */
426         else
427                 gig_dbg(DEBUG_IF, "%s: not implemented\n", __func__);
428
429         mutex_unlock(&cs->mutex);
430 }
431
432 static void if_set_termios(struct tty_struct *tty, struct ktermios *old)
433 {
434         struct cardstate *cs = tty->driver_data;
435         unsigned int iflag;
436         unsigned int cflag;
437         unsigned int old_cflag;
438         unsigned int control_state, new_state;
439
440         gig_dbg(DEBUG_IF, "%u: %s()", cs->minor_index, __func__);
441
442         mutex_lock(&cs->mutex);
443
444         if (!cs->connected) {
445                 gig_dbg(DEBUG_IF, "not connected");
446                 goto out;
447         }
448
449         iflag = tty->termios->c_iflag;
450         cflag = tty->termios->c_cflag;
451         old_cflag = old ? old->c_cflag : cflag;
452         gig_dbg(DEBUG_IF, "%u: iflag %x cflag %x old %x",
453                 cs->minor_index, iflag, cflag, old_cflag);
454
455         /* get a local copy of the current port settings */
456         control_state = cs->control_state;
457
458         /*
459          * Update baud rate.
460          * Do not attempt to cache old rates and skip settings,
461          * disconnects screw such tricks up completely.
462          * Premature optimization is the root of all evil.
463          */
464
465         /* reassert DTR and (maybe) RTS on transition from B0 */
466         if ((old_cflag & CBAUD) == B0) {
467                 new_state = control_state | TIOCM_DTR;
468                 /* don't set RTS if using hardware flow control */
469                 if (!(old_cflag & CRTSCTS))
470                         new_state |= TIOCM_RTS;
471                 gig_dbg(DEBUG_IF, "%u: from B0 - set DTR%s",
472                         cs->minor_index,
473                         (new_state & TIOCM_RTS) ? " only" : "/RTS");
474                 cs->ops->set_modem_ctrl(cs, control_state, new_state);
475                 control_state = new_state;
476         }
477
478         cs->ops->baud_rate(cs, cflag & CBAUD);
479
480         if ((cflag & CBAUD) == B0) {
481                 /* Drop RTS and DTR */
482                 gig_dbg(DEBUG_IF, "%u: to B0 - drop DTR/RTS", cs->minor_index);
483                 new_state = control_state & ~(TIOCM_DTR | TIOCM_RTS);
484                 cs->ops->set_modem_ctrl(cs, control_state, new_state);
485                 control_state = new_state;
486         }
487
488         /*
489          * Update line control register (LCR)
490          */
491
492         cs->ops->set_line_ctrl(cs, cflag);
493
494         /* save off the modified port settings */
495         cs->control_state = control_state;
496
497 out:
498         mutex_unlock(&cs->mutex);
499 }
500
501
502 /* wakeup tasklet for the write operation */
503 static void if_wake(unsigned long data)
504 {
505         struct cardstate *cs = (struct cardstate *)data;
506         struct tty_struct *tty = tty_port_tty_get(&cs->port);
507
508         if (tty) {
509                 tty_wakeup(tty);
510                 tty_kref_put(tty);
511         }
512 }
513
514 /*** interface to common ***/
515
516 void gigaset_if_init(struct cardstate *cs)
517 {
518         struct gigaset_driver *drv;
519
520         drv = cs->driver;
521         if (!drv->have_tty)
522                 return;
523
524         tasklet_init(&cs->if_wake_tasklet, if_wake, (unsigned long) cs);
525
526         mutex_lock(&cs->mutex);
527         cs->tty_dev = tty_register_device(drv->tty, cs->minor_index, NULL);
528
529         if (!IS_ERR(cs->tty_dev))
530                 dev_set_drvdata(cs->tty_dev, cs);
531         else {
532                 pr_warning("could not register device to the tty subsystem\n");
533                 cs->tty_dev = NULL;
534         }
535         mutex_unlock(&cs->mutex);
536 }
537
538 void gigaset_if_free(struct cardstate *cs)
539 {
540         struct gigaset_driver *drv;
541
542         drv = cs->driver;
543         if (!drv->have_tty)
544                 return;
545
546         tasklet_disable(&cs->if_wake_tasklet);
547         tasklet_kill(&cs->if_wake_tasklet);
548         cs->tty_dev = NULL;
549         tty_unregister_device(drv->tty, cs->minor_index);
550 }
551
552 /**
553  * gigaset_if_receive() - pass a received block of data to the tty device
554  * @cs:         device descriptor structure.
555  * @buffer:     received data.
556  * @len:        number of bytes received.
557  *
558  * Called by asyncdata/isocdata if a block of data received from the
559  * device must be sent to userspace through the ttyG* device.
560  */
561 void gigaset_if_receive(struct cardstate *cs,
562                         unsigned char *buffer, size_t len)
563 {
564         struct tty_struct *tty = tty_port_tty_get(&cs->port);
565
566         if (tty == NULL) {
567                 gig_dbg(DEBUG_IF, "receive on closed device");
568                 return;
569         }
570
571         tty_insert_flip_string(tty, buffer, len);
572         tty_flip_buffer_push(tty);
573         tty_kref_put(tty);
574 }
575 EXPORT_SYMBOL_GPL(gigaset_if_receive);
576
577 /* gigaset_if_initdriver
578  * Initialize tty interface.
579  * parameters:
580  *      drv             Driver
581  *      procname        Name of the driver (e.g. for /proc/tty/drivers)
582  *      devname         Name of the device files (prefix without minor number)
583  */
584 void gigaset_if_initdriver(struct gigaset_driver *drv, const char *procname,
585                            const char *devname)
586 {
587         int ret;
588         struct tty_driver *tty;
589
590         drv->have_tty = 0;
591
592         drv->tty = tty = alloc_tty_driver(drv->minors);
593         if (tty == NULL)
594                 goto enomem;
595
596         tty->type =             TTY_DRIVER_TYPE_SERIAL,
597         tty->subtype =          SERIAL_TYPE_NORMAL,
598         tty->flags =            TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
599
600         tty->driver_name =      procname;
601         tty->name =             devname;
602         tty->minor_start =      drv->minor;
603
604         tty->init_termios          = tty_std_termios;
605         tty->init_termios.c_cflag  = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
606         tty_set_operations(tty, &if_ops);
607
608         ret = tty_register_driver(tty);
609         if (ret < 0) {
610                 pr_err("error %d registering tty driver\n", ret);
611                 goto error;
612         }
613         gig_dbg(DEBUG_IF, "tty driver initialized");
614         drv->have_tty = 1;
615         return;
616
617 enomem:
618         pr_err("out of memory\n");
619 error:
620         if (drv->tty)
621                 put_tty_driver(drv->tty);
622 }
623
624 void gigaset_if_freedriver(struct gigaset_driver *drv)
625 {
626         if (!drv->have_tty)
627                 return;
628
629         drv->have_tty = 0;
630         tty_unregister_driver(drv->tty);
631         put_tty_driver(drv->tty);
632 }