arm64: mm: replace 'block_mappings_allowed' with 'page_mappings_only'
[linux/fpc-iii.git] / sound / core / timer.c
blobfc144f43faa67c177dba17a40c246a2af3edef7c
1 /*
2 * Timers abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <linux/delay.h>
23 #include <linux/init.h>
24 #include <linux/slab.h>
25 #include <linux/time.h>
26 #include <linux/mutex.h>
27 #include <linux/device.h>
28 #include <linux/module.h>
29 #include <linux/string.h>
30 #include <sound/core.h>
31 #include <sound/timer.h>
32 #include <sound/control.h>
33 #include <sound/info.h>
34 #include <sound/minors.h>
35 #include <sound/initval.h>
36 #include <linux/kmod.h>
38 /* internal flags */
39 #define SNDRV_TIMER_IFLG_PAUSED 0x00010000
41 #if IS_ENABLED(CONFIG_SND_HRTIMER)
42 #define DEFAULT_TIMER_LIMIT 4
43 #else
44 #define DEFAULT_TIMER_LIMIT 1
45 #endif
47 static int timer_limit = DEFAULT_TIMER_LIMIT;
48 static int timer_tstamp_monotonic = 1;
49 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>");
50 MODULE_DESCRIPTION("ALSA timer interface");
51 MODULE_LICENSE("GPL");
52 module_param(timer_limit, int, 0444);
53 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
54 module_param(timer_tstamp_monotonic, int, 0444);
55 MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
57 MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
58 MODULE_ALIAS("devname:snd/timer");
60 struct snd_timer_user {
61 struct snd_timer_instance *timeri;
62 int tread; /* enhanced read with timestamps and events */
63 unsigned long ticks;
64 unsigned long overrun;
65 int qhead;
66 int qtail;
67 int qused;
68 int queue_size;
69 bool disconnected;
70 struct snd_timer_read *queue;
71 struct snd_timer_tread *tqueue;
72 spinlock_t qlock;
73 unsigned long last_resolution;
74 unsigned int filter;
75 struct timespec tstamp; /* trigger tstamp */
76 wait_queue_head_t qchange_sleep;
77 struct fasync_struct *fasync;
78 struct mutex ioctl_lock;
81 /* list of timers */
82 static LIST_HEAD(snd_timer_list);
84 /* list of slave instances */
85 static LIST_HEAD(snd_timer_slave_list);
87 /* lock for slave active lists */
88 static DEFINE_SPINLOCK(slave_active_lock);
90 static DEFINE_MUTEX(register_mutex);
92 static int snd_timer_free(struct snd_timer *timer);
93 static int snd_timer_dev_free(struct snd_device *device);
94 static int snd_timer_dev_register(struct snd_device *device);
95 static int snd_timer_dev_disconnect(struct snd_device *device);
97 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
100 * create a timer instance with the given owner string.
101 * when timer is not NULL, increments the module counter
103 static struct snd_timer_instance *snd_timer_instance_new(char *owner,
104 struct snd_timer *timer)
106 struct snd_timer_instance *timeri;
107 timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
108 if (timeri == NULL)
109 return NULL;
110 timeri->owner = kstrdup(owner, GFP_KERNEL);
111 if (! timeri->owner) {
112 kfree(timeri);
113 return NULL;
115 INIT_LIST_HEAD(&timeri->open_list);
116 INIT_LIST_HEAD(&timeri->active_list);
117 INIT_LIST_HEAD(&timeri->ack_list);
118 INIT_LIST_HEAD(&timeri->slave_list_head);
119 INIT_LIST_HEAD(&timeri->slave_active_head);
121 timeri->timer = timer;
122 if (timer && !try_module_get(timer->module)) {
123 kfree(timeri->owner);
124 kfree(timeri);
125 return NULL;
128 return timeri;
132 * find a timer instance from the given timer id
134 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
136 struct snd_timer *timer = NULL;
138 list_for_each_entry(timer, &snd_timer_list, device_list) {
139 if (timer->tmr_class != tid->dev_class)
140 continue;
141 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
142 timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
143 (timer->card == NULL ||
144 timer->card->number != tid->card))
145 continue;
146 if (timer->tmr_device != tid->device)
147 continue;
148 if (timer->tmr_subdevice != tid->subdevice)
149 continue;
150 return timer;
152 return NULL;
155 #ifdef CONFIG_MODULES
157 static void snd_timer_request(struct snd_timer_id *tid)
159 switch (tid->dev_class) {
160 case SNDRV_TIMER_CLASS_GLOBAL:
161 if (tid->device < timer_limit)
162 request_module("snd-timer-%i", tid->device);
163 break;
164 case SNDRV_TIMER_CLASS_CARD:
165 case SNDRV_TIMER_CLASS_PCM:
166 if (tid->card < snd_ecards_limit)
167 request_module("snd-card-%i", tid->card);
168 break;
169 default:
170 break;
174 #endif
177 * look for a master instance matching with the slave id of the given slave.
178 * when found, relink the open_link of the slave.
180 * call this with register_mutex down.
182 static void snd_timer_check_slave(struct snd_timer_instance *slave)
184 struct snd_timer *timer;
185 struct snd_timer_instance *master;
187 /* FIXME: it's really dumb to look up all entries.. */
188 list_for_each_entry(timer, &snd_timer_list, device_list) {
189 list_for_each_entry(master, &timer->open_list_head, open_list) {
190 if (slave->slave_class == master->slave_class &&
191 slave->slave_id == master->slave_id) {
192 list_move_tail(&slave->open_list,
193 &master->slave_list_head);
194 spin_lock_irq(&slave_active_lock);
195 slave->master = master;
196 slave->timer = master->timer;
197 spin_unlock_irq(&slave_active_lock);
198 return;
205 * look for slave instances matching with the slave id of the given master.
206 * when found, relink the open_link of slaves.
208 * call this with register_mutex down.
210 static void snd_timer_check_master(struct snd_timer_instance *master)
212 struct snd_timer_instance *slave, *tmp;
214 /* check all pending slaves */
215 list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
216 if (slave->slave_class == master->slave_class &&
217 slave->slave_id == master->slave_id) {
218 list_move_tail(&slave->open_list, &master->slave_list_head);
219 spin_lock_irq(&slave_active_lock);
220 spin_lock(&master->timer->lock);
221 slave->master = master;
222 slave->timer = master->timer;
223 if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
224 list_add_tail(&slave->active_list,
225 &master->slave_active_head);
226 spin_unlock(&master->timer->lock);
227 spin_unlock_irq(&slave_active_lock);
233 * open a timer instance
234 * when opening a master, the slave id must be here given.
236 int snd_timer_open(struct snd_timer_instance **ti,
237 char *owner, struct snd_timer_id *tid,
238 unsigned int slave_id)
240 struct snd_timer *timer;
241 struct snd_timer_instance *timeri = NULL;
243 if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
244 /* open a slave instance */
245 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
246 tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
247 pr_debug("ALSA: timer: invalid slave class %i\n",
248 tid->dev_sclass);
249 return -EINVAL;
251 mutex_lock(&register_mutex);
252 timeri = snd_timer_instance_new(owner, NULL);
253 if (!timeri) {
254 mutex_unlock(&register_mutex);
255 return -ENOMEM;
257 timeri->slave_class = tid->dev_sclass;
258 timeri->slave_id = tid->device;
259 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
260 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
261 snd_timer_check_slave(timeri);
262 mutex_unlock(&register_mutex);
263 *ti = timeri;
264 return 0;
267 /* open a master instance */
268 mutex_lock(&register_mutex);
269 timer = snd_timer_find(tid);
270 #ifdef CONFIG_MODULES
271 if (!timer) {
272 mutex_unlock(&register_mutex);
273 snd_timer_request(tid);
274 mutex_lock(&register_mutex);
275 timer = snd_timer_find(tid);
277 #endif
278 if (!timer) {
279 mutex_unlock(&register_mutex);
280 return -ENODEV;
282 if (!list_empty(&timer->open_list_head)) {
283 timeri = list_entry(timer->open_list_head.next,
284 struct snd_timer_instance, open_list);
285 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
286 mutex_unlock(&register_mutex);
287 return -EBUSY;
290 timeri = snd_timer_instance_new(owner, timer);
291 if (!timeri) {
292 mutex_unlock(&register_mutex);
293 return -ENOMEM;
295 /* take a card refcount for safe disconnection */
296 if (timer->card)
297 get_device(&timer->card->card_dev);
298 timeri->slave_class = tid->dev_sclass;
299 timeri->slave_id = slave_id;
301 if (list_empty(&timer->open_list_head) && timer->hw.open) {
302 int err = timer->hw.open(timer);
303 if (err) {
304 kfree(timeri->owner);
305 kfree(timeri);
307 if (timer->card)
308 put_device(&timer->card->card_dev);
309 module_put(timer->module);
310 mutex_unlock(&register_mutex);
311 return err;
315 list_add_tail(&timeri->open_list, &timer->open_list_head);
316 snd_timer_check_master(timeri);
317 mutex_unlock(&register_mutex);
318 *ti = timeri;
319 return 0;
323 * close a timer instance
325 int snd_timer_close(struct snd_timer_instance *timeri)
327 struct snd_timer *timer = NULL;
328 struct snd_timer_instance *slave, *tmp;
330 if (snd_BUG_ON(!timeri))
331 return -ENXIO;
333 mutex_lock(&register_mutex);
334 list_del(&timeri->open_list);
336 /* force to stop the timer */
337 snd_timer_stop(timeri);
339 timer = timeri->timer;
340 if (timer) {
341 /* wait, until the active callback is finished */
342 spin_lock_irq(&timer->lock);
343 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
344 spin_unlock_irq(&timer->lock);
345 udelay(10);
346 spin_lock_irq(&timer->lock);
348 spin_unlock_irq(&timer->lock);
350 /* remove slave links */
351 spin_lock_irq(&slave_active_lock);
352 spin_lock(&timer->lock);
353 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
354 open_list) {
355 list_move_tail(&slave->open_list, &snd_timer_slave_list);
356 slave->master = NULL;
357 slave->timer = NULL;
358 list_del_init(&slave->ack_list);
359 list_del_init(&slave->active_list);
361 spin_unlock(&timer->lock);
362 spin_unlock_irq(&slave_active_lock);
364 /* slave doesn't need to release timer resources below */
365 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
366 timer = NULL;
369 if (timeri->private_free)
370 timeri->private_free(timeri);
371 kfree(timeri->owner);
372 kfree(timeri);
374 if (timer) {
375 if (list_empty(&timer->open_list_head) && timer->hw.close)
376 timer->hw.close(timer);
377 /* release a card refcount for safe disconnection */
378 if (timer->card)
379 put_device(&timer->card->card_dev);
380 module_put(timer->module);
383 mutex_unlock(&register_mutex);
384 return 0;
387 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
389 struct snd_timer * timer;
391 if (timeri == NULL)
392 return 0;
393 if ((timer = timeri->timer) != NULL) {
394 if (timer->hw.c_resolution)
395 return timer->hw.c_resolution(timer);
396 return timer->hw.resolution;
398 return 0;
401 static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
403 struct snd_timer *timer;
404 unsigned long resolution = 0;
405 struct snd_timer_instance *ts;
406 struct timespec tstamp;
408 if (timer_tstamp_monotonic)
409 ktime_get_ts(&tstamp);
410 else
411 getnstimeofday(&tstamp);
412 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
413 event > SNDRV_TIMER_EVENT_PAUSE))
414 return;
415 if (event == SNDRV_TIMER_EVENT_START ||
416 event == SNDRV_TIMER_EVENT_CONTINUE)
417 resolution = snd_timer_resolution(ti);
418 if (ti->ccallback)
419 ti->ccallback(ti, event, &tstamp, resolution);
420 if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
421 return;
422 timer = ti->timer;
423 if (timer == NULL)
424 return;
425 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
426 return;
427 list_for_each_entry(ts, &ti->slave_active_head, active_list)
428 if (ts->ccallback)
429 ts->ccallback(ts, event + 100, &tstamp, resolution);
432 /* start/continue a master timer */
433 static int snd_timer_start1(struct snd_timer_instance *timeri,
434 bool start, unsigned long ticks)
436 struct snd_timer *timer;
437 int result;
438 unsigned long flags;
440 timer = timeri->timer;
441 if (!timer)
442 return -EINVAL;
444 spin_lock_irqsave(&timer->lock, flags);
445 if (timer->card && timer->card->shutdown) {
446 result = -ENODEV;
447 goto unlock;
449 if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
450 SNDRV_TIMER_IFLG_START)) {
451 result = -EBUSY;
452 goto unlock;
455 if (start)
456 timeri->ticks = timeri->cticks = ticks;
457 else if (!timeri->cticks)
458 timeri->cticks = 1;
459 timeri->pticks = 0;
461 list_move_tail(&timeri->active_list, &timer->active_list_head);
462 if (timer->running) {
463 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
464 goto __start_now;
465 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
466 timeri->flags |= SNDRV_TIMER_IFLG_START;
467 result = 1; /* delayed start */
468 } else {
469 if (start)
470 timer->sticks = ticks;
471 timer->hw.start(timer);
472 __start_now:
473 timer->running++;
474 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
475 result = 0;
477 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
478 SNDRV_TIMER_EVENT_CONTINUE);
479 unlock:
480 spin_unlock_irqrestore(&timer->lock, flags);
481 return result;
484 /* start/continue a slave timer */
485 static int snd_timer_start_slave(struct snd_timer_instance *timeri,
486 bool start)
488 unsigned long flags;
490 spin_lock_irqsave(&slave_active_lock, flags);
491 if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) {
492 spin_unlock_irqrestore(&slave_active_lock, flags);
493 return -EBUSY;
495 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
496 if (timeri->master && timeri->timer) {
497 spin_lock(&timeri->timer->lock);
498 list_add_tail(&timeri->active_list,
499 &timeri->master->slave_active_head);
500 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
501 SNDRV_TIMER_EVENT_CONTINUE);
502 spin_unlock(&timeri->timer->lock);
504 spin_unlock_irqrestore(&slave_active_lock, flags);
505 return 1; /* delayed start */
508 /* stop/pause a master timer */
509 static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
511 struct snd_timer *timer;
512 int result = 0;
513 unsigned long flags;
515 timer = timeri->timer;
516 if (!timer)
517 return -EINVAL;
518 spin_lock_irqsave(&timer->lock, flags);
519 if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
520 SNDRV_TIMER_IFLG_START))) {
521 result = -EBUSY;
522 goto unlock;
524 list_del_init(&timeri->ack_list);
525 list_del_init(&timeri->active_list);
526 if (timer->card && timer->card->shutdown)
527 goto unlock;
528 if (stop) {
529 timeri->cticks = timeri->ticks;
530 timeri->pticks = 0;
532 if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
533 !(--timer->running)) {
534 timer->hw.stop(timer);
535 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
536 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
537 snd_timer_reschedule(timer, 0);
538 if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
539 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
540 timer->hw.start(timer);
544 timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
545 if (stop)
546 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
547 else
548 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
549 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
550 SNDRV_TIMER_EVENT_CONTINUE);
551 unlock:
552 spin_unlock_irqrestore(&timer->lock, flags);
553 return result;
556 /* stop/pause a slave timer */
557 static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
559 unsigned long flags;
561 spin_lock_irqsave(&slave_active_lock, flags);
562 if (!(timeri->flags & SNDRV_TIMER_IFLG_RUNNING)) {
563 spin_unlock_irqrestore(&slave_active_lock, flags);
564 return -EBUSY;
566 timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
567 if (timeri->timer) {
568 spin_lock(&timeri->timer->lock);
569 list_del_init(&timeri->ack_list);
570 list_del_init(&timeri->active_list);
571 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
572 SNDRV_TIMER_EVENT_CONTINUE);
573 spin_unlock(&timeri->timer->lock);
575 spin_unlock_irqrestore(&slave_active_lock, flags);
576 return 0;
580 * start the timer instance
582 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
584 if (timeri == NULL || ticks < 1)
585 return -EINVAL;
586 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
587 return snd_timer_start_slave(timeri, true);
588 else
589 return snd_timer_start1(timeri, true, ticks);
593 * stop the timer instance.
595 * do not call this from the timer callback!
597 int snd_timer_stop(struct snd_timer_instance *timeri)
599 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
600 return snd_timer_stop_slave(timeri, true);
601 else
602 return snd_timer_stop1(timeri, true);
606 * start again.. the tick is kept.
608 int snd_timer_continue(struct snd_timer_instance *timeri)
610 /* timer can continue only after pause */
611 if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
612 return -EINVAL;
614 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
615 return snd_timer_start_slave(timeri, false);
616 else
617 return snd_timer_start1(timeri, false, 0);
621 * pause.. remember the ticks left
623 int snd_timer_pause(struct snd_timer_instance * timeri)
625 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
626 return snd_timer_stop_slave(timeri, false);
627 else
628 return snd_timer_stop1(timeri, false);
632 * reschedule the timer
634 * start pending instances and check the scheduling ticks.
635 * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
637 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
639 struct snd_timer_instance *ti;
640 unsigned long ticks = ~0UL;
642 list_for_each_entry(ti, &timer->active_list_head, active_list) {
643 if (ti->flags & SNDRV_TIMER_IFLG_START) {
644 ti->flags &= ~SNDRV_TIMER_IFLG_START;
645 ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
646 timer->running++;
648 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
649 if (ticks > ti->cticks)
650 ticks = ti->cticks;
653 if (ticks == ~0UL) {
654 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
655 return;
657 if (ticks > timer->hw.ticks)
658 ticks = timer->hw.ticks;
659 if (ticks_left != ticks)
660 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
661 timer->sticks = ticks;
665 * timer tasklet
668 static void snd_timer_tasklet(unsigned long arg)
670 struct snd_timer *timer = (struct snd_timer *) arg;
671 struct snd_timer_instance *ti;
672 struct list_head *p;
673 unsigned long resolution, ticks;
674 unsigned long flags;
676 if (timer->card && timer->card->shutdown)
677 return;
679 spin_lock_irqsave(&timer->lock, flags);
680 /* now process all callbacks */
681 while (!list_empty(&timer->sack_list_head)) {
682 p = timer->sack_list_head.next; /* get first item */
683 ti = list_entry(p, struct snd_timer_instance, ack_list);
685 /* remove from ack_list and make empty */
686 list_del_init(p);
688 ticks = ti->pticks;
689 ti->pticks = 0;
690 resolution = ti->resolution;
692 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
693 spin_unlock(&timer->lock);
694 if (ti->callback)
695 ti->callback(ti, resolution, ticks);
696 spin_lock(&timer->lock);
697 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
699 spin_unlock_irqrestore(&timer->lock, flags);
703 * timer interrupt
705 * ticks_left is usually equal to timer->sticks.
708 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
710 struct snd_timer_instance *ti, *ts, *tmp;
711 unsigned long resolution, ticks;
712 struct list_head *p, *ack_list_head;
713 unsigned long flags;
714 int use_tasklet = 0;
716 if (timer == NULL)
717 return;
719 if (timer->card && timer->card->shutdown)
720 return;
722 spin_lock_irqsave(&timer->lock, flags);
724 /* remember the current resolution */
725 if (timer->hw.c_resolution)
726 resolution = timer->hw.c_resolution(timer);
727 else
728 resolution = timer->hw.resolution;
730 /* loop for all active instances
731 * Here we cannot use list_for_each_entry because the active_list of a
732 * processed instance is relinked to done_list_head before the callback
733 * is called.
735 list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
736 active_list) {
737 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
738 continue;
739 ti->pticks += ticks_left;
740 ti->resolution = resolution;
741 if (ti->cticks < ticks_left)
742 ti->cticks = 0;
743 else
744 ti->cticks -= ticks_left;
745 if (ti->cticks) /* not expired */
746 continue;
747 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
748 ti->cticks = ti->ticks;
749 } else {
750 ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
751 --timer->running;
752 list_del_init(&ti->active_list);
754 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
755 (ti->flags & SNDRV_TIMER_IFLG_FAST))
756 ack_list_head = &timer->ack_list_head;
757 else
758 ack_list_head = &timer->sack_list_head;
759 if (list_empty(&ti->ack_list))
760 list_add_tail(&ti->ack_list, ack_list_head);
761 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
762 ts->pticks = ti->pticks;
763 ts->resolution = resolution;
764 if (list_empty(&ts->ack_list))
765 list_add_tail(&ts->ack_list, ack_list_head);
768 if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
769 snd_timer_reschedule(timer, timer->sticks);
770 if (timer->running) {
771 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
772 timer->hw.stop(timer);
773 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
775 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
776 (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
777 /* restart timer */
778 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
779 timer->hw.start(timer);
781 } else {
782 timer->hw.stop(timer);
785 /* now process all fast callbacks */
786 while (!list_empty(&timer->ack_list_head)) {
787 p = timer->ack_list_head.next; /* get first item */
788 ti = list_entry(p, struct snd_timer_instance, ack_list);
790 /* remove from ack_list and make empty */
791 list_del_init(p);
793 ticks = ti->pticks;
794 ti->pticks = 0;
796 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
797 spin_unlock(&timer->lock);
798 if (ti->callback)
799 ti->callback(ti, resolution, ticks);
800 spin_lock(&timer->lock);
801 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
804 /* do we have any slow callbacks? */
805 use_tasklet = !list_empty(&timer->sack_list_head);
806 spin_unlock_irqrestore(&timer->lock, flags);
808 if (use_tasklet)
809 tasklet_schedule(&timer->task_queue);
816 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
817 struct snd_timer **rtimer)
819 struct snd_timer *timer;
820 int err;
821 static struct snd_device_ops ops = {
822 .dev_free = snd_timer_dev_free,
823 .dev_register = snd_timer_dev_register,
824 .dev_disconnect = snd_timer_dev_disconnect,
827 if (snd_BUG_ON(!tid))
828 return -EINVAL;
829 if (rtimer)
830 *rtimer = NULL;
831 timer = kzalloc(sizeof(*timer), GFP_KERNEL);
832 if (!timer)
833 return -ENOMEM;
834 timer->tmr_class = tid->dev_class;
835 timer->card = card;
836 timer->tmr_device = tid->device;
837 timer->tmr_subdevice = tid->subdevice;
838 if (id)
839 strlcpy(timer->id, id, sizeof(timer->id));
840 timer->sticks = 1;
841 INIT_LIST_HEAD(&timer->device_list);
842 INIT_LIST_HEAD(&timer->open_list_head);
843 INIT_LIST_HEAD(&timer->active_list_head);
844 INIT_LIST_HEAD(&timer->ack_list_head);
845 INIT_LIST_HEAD(&timer->sack_list_head);
846 spin_lock_init(&timer->lock);
847 tasklet_init(&timer->task_queue, snd_timer_tasklet,
848 (unsigned long)timer);
849 if (card != NULL) {
850 timer->module = card->module;
851 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
852 if (err < 0) {
853 snd_timer_free(timer);
854 return err;
857 if (rtimer)
858 *rtimer = timer;
859 return 0;
862 static int snd_timer_free(struct snd_timer *timer)
864 if (!timer)
865 return 0;
867 mutex_lock(&register_mutex);
868 if (! list_empty(&timer->open_list_head)) {
869 struct list_head *p, *n;
870 struct snd_timer_instance *ti;
871 pr_warn("ALSA: timer %p is busy?\n", timer);
872 list_for_each_safe(p, n, &timer->open_list_head) {
873 list_del_init(p);
874 ti = list_entry(p, struct snd_timer_instance, open_list);
875 ti->timer = NULL;
878 list_del(&timer->device_list);
879 mutex_unlock(&register_mutex);
881 if (timer->private_free)
882 timer->private_free(timer);
883 kfree(timer);
884 return 0;
887 static int snd_timer_dev_free(struct snd_device *device)
889 struct snd_timer *timer = device->device_data;
890 return snd_timer_free(timer);
893 static int snd_timer_dev_register(struct snd_device *dev)
895 struct snd_timer *timer = dev->device_data;
896 struct snd_timer *timer1;
898 if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
899 return -ENXIO;
900 if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
901 !timer->hw.resolution && timer->hw.c_resolution == NULL)
902 return -EINVAL;
904 mutex_lock(&register_mutex);
905 list_for_each_entry(timer1, &snd_timer_list, device_list) {
906 if (timer1->tmr_class > timer->tmr_class)
907 break;
908 if (timer1->tmr_class < timer->tmr_class)
909 continue;
910 if (timer1->card && timer->card) {
911 if (timer1->card->number > timer->card->number)
912 break;
913 if (timer1->card->number < timer->card->number)
914 continue;
916 if (timer1->tmr_device > timer->tmr_device)
917 break;
918 if (timer1->tmr_device < timer->tmr_device)
919 continue;
920 if (timer1->tmr_subdevice > timer->tmr_subdevice)
921 break;
922 if (timer1->tmr_subdevice < timer->tmr_subdevice)
923 continue;
924 /* conflicts.. */
925 mutex_unlock(&register_mutex);
926 return -EBUSY;
928 list_add_tail(&timer->device_list, &timer1->device_list);
929 mutex_unlock(&register_mutex);
930 return 0;
933 static int snd_timer_dev_disconnect(struct snd_device *device)
935 struct snd_timer *timer = device->device_data;
936 struct snd_timer_instance *ti;
938 mutex_lock(&register_mutex);
939 list_del_init(&timer->device_list);
940 /* wake up pending sleepers */
941 list_for_each_entry(ti, &timer->open_list_head, open_list) {
942 if (ti->disconnect)
943 ti->disconnect(ti);
945 mutex_unlock(&register_mutex);
946 return 0;
949 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
951 unsigned long flags;
952 unsigned long resolution = 0;
953 struct snd_timer_instance *ti, *ts;
955 if (timer->card && timer->card->shutdown)
956 return;
957 if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
958 return;
959 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
960 event > SNDRV_TIMER_EVENT_MRESUME))
961 return;
962 spin_lock_irqsave(&timer->lock, flags);
963 if (event == SNDRV_TIMER_EVENT_MSTART ||
964 event == SNDRV_TIMER_EVENT_MCONTINUE ||
965 event == SNDRV_TIMER_EVENT_MRESUME) {
966 if (timer->hw.c_resolution)
967 resolution = timer->hw.c_resolution(timer);
968 else
969 resolution = timer->hw.resolution;
971 list_for_each_entry(ti, &timer->active_list_head, active_list) {
972 if (ti->ccallback)
973 ti->ccallback(ti, event, tstamp, resolution);
974 list_for_each_entry(ts, &ti->slave_active_head, active_list)
975 if (ts->ccallback)
976 ts->ccallback(ts, event, tstamp, resolution);
978 spin_unlock_irqrestore(&timer->lock, flags);
982 * exported functions for global timers
984 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
986 struct snd_timer_id tid;
988 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
989 tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
990 tid.card = -1;
991 tid.device = device;
992 tid.subdevice = 0;
993 return snd_timer_new(NULL, id, &tid, rtimer);
996 int snd_timer_global_free(struct snd_timer *timer)
998 return snd_timer_free(timer);
1001 int snd_timer_global_register(struct snd_timer *timer)
1003 struct snd_device dev;
1005 memset(&dev, 0, sizeof(dev));
1006 dev.device_data = timer;
1007 return snd_timer_dev_register(&dev);
1011 * System timer
1014 struct snd_timer_system_private {
1015 struct timer_list tlist;
1016 unsigned long last_expires;
1017 unsigned long last_jiffies;
1018 unsigned long correction;
1021 static void snd_timer_s_function(unsigned long data)
1023 struct snd_timer *timer = (struct snd_timer *)data;
1024 struct snd_timer_system_private *priv = timer->private_data;
1025 unsigned long jiff = jiffies;
1026 if (time_after(jiff, priv->last_expires))
1027 priv->correction += (long)jiff - (long)priv->last_expires;
1028 snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1031 static int snd_timer_s_start(struct snd_timer * timer)
1033 struct snd_timer_system_private *priv;
1034 unsigned long njiff;
1036 priv = (struct snd_timer_system_private *) timer->private_data;
1037 njiff = (priv->last_jiffies = jiffies);
1038 if (priv->correction > timer->sticks - 1) {
1039 priv->correction -= timer->sticks - 1;
1040 njiff++;
1041 } else {
1042 njiff += timer->sticks - priv->correction;
1043 priv->correction = 0;
1045 priv->last_expires = njiff;
1046 mod_timer(&priv->tlist, njiff);
1047 return 0;
1050 static int snd_timer_s_stop(struct snd_timer * timer)
1052 struct snd_timer_system_private *priv;
1053 unsigned long jiff;
1055 priv = (struct snd_timer_system_private *) timer->private_data;
1056 del_timer(&priv->tlist);
1057 jiff = jiffies;
1058 if (time_before(jiff, priv->last_expires))
1059 timer->sticks = priv->last_expires - jiff;
1060 else
1061 timer->sticks = 1;
1062 priv->correction = 0;
1063 return 0;
1066 static int snd_timer_s_close(struct snd_timer *timer)
1068 struct snd_timer_system_private *priv;
1070 priv = (struct snd_timer_system_private *)timer->private_data;
1071 del_timer_sync(&priv->tlist);
1072 return 0;
1075 static struct snd_timer_hardware snd_timer_system =
1077 .flags = SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
1078 .resolution = 1000000000L / HZ,
1079 .ticks = 10000000L,
1080 .close = snd_timer_s_close,
1081 .start = snd_timer_s_start,
1082 .stop = snd_timer_s_stop
1085 static void snd_timer_free_system(struct snd_timer *timer)
1087 kfree(timer->private_data);
1090 static int snd_timer_register_system(void)
1092 struct snd_timer *timer;
1093 struct snd_timer_system_private *priv;
1094 int err;
1096 err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1097 if (err < 0)
1098 return err;
1099 strcpy(timer->name, "system timer");
1100 timer->hw = snd_timer_system;
1101 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1102 if (priv == NULL) {
1103 snd_timer_free(timer);
1104 return -ENOMEM;
1106 setup_timer(&priv->tlist, snd_timer_s_function, (unsigned long) timer);
1107 timer->private_data = priv;
1108 timer->private_free = snd_timer_free_system;
1109 return snd_timer_global_register(timer);
1112 #ifdef CONFIG_SND_PROC_FS
1114 * Info interface
1117 static void snd_timer_proc_read(struct snd_info_entry *entry,
1118 struct snd_info_buffer *buffer)
1120 struct snd_timer *timer;
1121 struct snd_timer_instance *ti;
1123 mutex_lock(&register_mutex);
1124 list_for_each_entry(timer, &snd_timer_list, device_list) {
1125 if (timer->card && timer->card->shutdown)
1126 continue;
1127 switch (timer->tmr_class) {
1128 case SNDRV_TIMER_CLASS_GLOBAL:
1129 snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1130 break;
1131 case SNDRV_TIMER_CLASS_CARD:
1132 snd_iprintf(buffer, "C%i-%i: ",
1133 timer->card->number, timer->tmr_device);
1134 break;
1135 case SNDRV_TIMER_CLASS_PCM:
1136 snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1137 timer->tmr_device, timer->tmr_subdevice);
1138 break;
1139 default:
1140 snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1141 timer->card ? timer->card->number : -1,
1142 timer->tmr_device, timer->tmr_subdevice);
1144 snd_iprintf(buffer, "%s :", timer->name);
1145 if (timer->hw.resolution)
1146 snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1147 timer->hw.resolution / 1000,
1148 timer->hw.resolution % 1000,
1149 timer->hw.ticks);
1150 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1151 snd_iprintf(buffer, " SLAVE");
1152 snd_iprintf(buffer, "\n");
1153 list_for_each_entry(ti, &timer->open_list_head, open_list)
1154 snd_iprintf(buffer, " Client %s : %s\n",
1155 ti->owner ? ti->owner : "unknown",
1156 ti->flags & (SNDRV_TIMER_IFLG_START |
1157 SNDRV_TIMER_IFLG_RUNNING)
1158 ? "running" : "stopped");
1160 mutex_unlock(&register_mutex);
1163 static struct snd_info_entry *snd_timer_proc_entry;
1165 static void __init snd_timer_proc_init(void)
1167 struct snd_info_entry *entry;
1169 entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1170 if (entry != NULL) {
1171 entry->c.text.read = snd_timer_proc_read;
1172 if (snd_info_register(entry) < 0) {
1173 snd_info_free_entry(entry);
1174 entry = NULL;
1177 snd_timer_proc_entry = entry;
1180 static void __exit snd_timer_proc_done(void)
1182 snd_info_free_entry(snd_timer_proc_entry);
1184 #else /* !CONFIG_SND_PROC_FS */
1185 #define snd_timer_proc_init()
1186 #define snd_timer_proc_done()
1187 #endif
1190 * USER SPACE interface
1193 static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1194 unsigned long resolution,
1195 unsigned long ticks)
1197 struct snd_timer_user *tu = timeri->callback_data;
1198 struct snd_timer_read *r;
1199 int prev;
1201 spin_lock(&tu->qlock);
1202 if (tu->qused > 0) {
1203 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1204 r = &tu->queue[prev];
1205 if (r->resolution == resolution) {
1206 r->ticks += ticks;
1207 goto __wake;
1210 if (tu->qused >= tu->queue_size) {
1211 tu->overrun++;
1212 } else {
1213 r = &tu->queue[tu->qtail++];
1214 tu->qtail %= tu->queue_size;
1215 r->resolution = resolution;
1216 r->ticks = ticks;
1217 tu->qused++;
1219 __wake:
1220 spin_unlock(&tu->qlock);
1221 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1222 wake_up(&tu->qchange_sleep);
1225 static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1226 struct snd_timer_tread *tread)
1228 if (tu->qused >= tu->queue_size) {
1229 tu->overrun++;
1230 } else {
1231 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1232 tu->qtail %= tu->queue_size;
1233 tu->qused++;
1237 static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1238 int event,
1239 struct timespec *tstamp,
1240 unsigned long resolution)
1242 struct snd_timer_user *tu = timeri->callback_data;
1243 struct snd_timer_tread r1;
1244 unsigned long flags;
1246 if (event >= SNDRV_TIMER_EVENT_START &&
1247 event <= SNDRV_TIMER_EVENT_PAUSE)
1248 tu->tstamp = *tstamp;
1249 if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1250 return;
1251 memset(&r1, 0, sizeof(r1));
1252 r1.event = event;
1253 r1.tstamp = *tstamp;
1254 r1.val = resolution;
1255 spin_lock_irqsave(&tu->qlock, flags);
1256 snd_timer_user_append_to_tqueue(tu, &r1);
1257 spin_unlock_irqrestore(&tu->qlock, flags);
1258 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1259 wake_up(&tu->qchange_sleep);
1262 static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1264 struct snd_timer_user *tu = timeri->callback_data;
1266 tu->disconnected = true;
1267 wake_up(&tu->qchange_sleep);
1270 static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1271 unsigned long resolution,
1272 unsigned long ticks)
1274 struct snd_timer_user *tu = timeri->callback_data;
1275 struct snd_timer_tread *r, r1;
1276 struct timespec tstamp;
1277 int prev, append = 0;
1279 memset(&tstamp, 0, sizeof(tstamp));
1280 spin_lock(&tu->qlock);
1281 if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1282 (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1283 spin_unlock(&tu->qlock);
1284 return;
1286 if (tu->last_resolution != resolution || ticks > 0) {
1287 if (timer_tstamp_monotonic)
1288 ktime_get_ts(&tstamp);
1289 else
1290 getnstimeofday(&tstamp);
1292 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1293 tu->last_resolution != resolution) {
1294 memset(&r1, 0, sizeof(r1));
1295 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1296 r1.tstamp = tstamp;
1297 r1.val = resolution;
1298 snd_timer_user_append_to_tqueue(tu, &r1);
1299 tu->last_resolution = resolution;
1300 append++;
1302 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1303 goto __wake;
1304 if (ticks == 0)
1305 goto __wake;
1306 if (tu->qused > 0) {
1307 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1308 r = &tu->tqueue[prev];
1309 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1310 r->tstamp = tstamp;
1311 r->val += ticks;
1312 append++;
1313 goto __wake;
1316 r1.event = SNDRV_TIMER_EVENT_TICK;
1317 r1.tstamp = tstamp;
1318 r1.val = ticks;
1319 snd_timer_user_append_to_tqueue(tu, &r1);
1320 append++;
1321 __wake:
1322 spin_unlock(&tu->qlock);
1323 if (append == 0)
1324 return;
1325 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1326 wake_up(&tu->qchange_sleep);
1329 static int snd_timer_user_open(struct inode *inode, struct file *file)
1331 struct snd_timer_user *tu;
1332 int err;
1334 err = nonseekable_open(inode, file);
1335 if (err < 0)
1336 return err;
1338 tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1339 if (tu == NULL)
1340 return -ENOMEM;
1341 spin_lock_init(&tu->qlock);
1342 init_waitqueue_head(&tu->qchange_sleep);
1343 mutex_init(&tu->ioctl_lock);
1344 tu->ticks = 1;
1345 tu->queue_size = 128;
1346 tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1347 GFP_KERNEL);
1348 if (tu->queue == NULL) {
1349 kfree(tu);
1350 return -ENOMEM;
1352 file->private_data = tu;
1353 return 0;
1356 static int snd_timer_user_release(struct inode *inode, struct file *file)
1358 struct snd_timer_user *tu;
1360 if (file->private_data) {
1361 tu = file->private_data;
1362 file->private_data = NULL;
1363 mutex_lock(&tu->ioctl_lock);
1364 if (tu->timeri)
1365 snd_timer_close(tu->timeri);
1366 mutex_unlock(&tu->ioctl_lock);
1367 kfree(tu->queue);
1368 kfree(tu->tqueue);
1369 kfree(tu);
1371 return 0;
1374 static void snd_timer_user_zero_id(struct snd_timer_id *id)
1376 id->dev_class = SNDRV_TIMER_CLASS_NONE;
1377 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1378 id->card = -1;
1379 id->device = -1;
1380 id->subdevice = -1;
1383 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1385 id->dev_class = timer->tmr_class;
1386 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1387 id->card = timer->card ? timer->card->number : -1;
1388 id->device = timer->tmr_device;
1389 id->subdevice = timer->tmr_subdevice;
1392 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1394 struct snd_timer_id id;
1395 struct snd_timer *timer;
1396 struct list_head *p;
1398 if (copy_from_user(&id, _tid, sizeof(id)))
1399 return -EFAULT;
1400 mutex_lock(&register_mutex);
1401 if (id.dev_class < 0) { /* first item */
1402 if (list_empty(&snd_timer_list))
1403 snd_timer_user_zero_id(&id);
1404 else {
1405 timer = list_entry(snd_timer_list.next,
1406 struct snd_timer, device_list);
1407 snd_timer_user_copy_id(&id, timer);
1409 } else {
1410 switch (id.dev_class) {
1411 case SNDRV_TIMER_CLASS_GLOBAL:
1412 id.device = id.device < 0 ? 0 : id.device + 1;
1413 list_for_each(p, &snd_timer_list) {
1414 timer = list_entry(p, struct snd_timer, device_list);
1415 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1416 snd_timer_user_copy_id(&id, timer);
1417 break;
1419 if (timer->tmr_device >= id.device) {
1420 snd_timer_user_copy_id(&id, timer);
1421 break;
1424 if (p == &snd_timer_list)
1425 snd_timer_user_zero_id(&id);
1426 break;
1427 case SNDRV_TIMER_CLASS_CARD:
1428 case SNDRV_TIMER_CLASS_PCM:
1429 if (id.card < 0) {
1430 id.card = 0;
1431 } else {
1432 if (id.card < 0) {
1433 id.card = 0;
1434 } else {
1435 if (id.device < 0) {
1436 id.device = 0;
1437 } else {
1438 if (id.subdevice < 0) {
1439 id.subdevice = 0;
1440 } else {
1441 id.subdevice++;
1446 list_for_each(p, &snd_timer_list) {
1447 timer = list_entry(p, struct snd_timer, device_list);
1448 if (timer->tmr_class > id.dev_class) {
1449 snd_timer_user_copy_id(&id, timer);
1450 break;
1452 if (timer->tmr_class < id.dev_class)
1453 continue;
1454 if (timer->card->number > id.card) {
1455 snd_timer_user_copy_id(&id, timer);
1456 break;
1458 if (timer->card->number < id.card)
1459 continue;
1460 if (timer->tmr_device > id.device) {
1461 snd_timer_user_copy_id(&id, timer);
1462 break;
1464 if (timer->tmr_device < id.device)
1465 continue;
1466 if (timer->tmr_subdevice > id.subdevice) {
1467 snd_timer_user_copy_id(&id, timer);
1468 break;
1470 if (timer->tmr_subdevice < id.subdevice)
1471 continue;
1472 snd_timer_user_copy_id(&id, timer);
1473 break;
1475 if (p == &snd_timer_list)
1476 snd_timer_user_zero_id(&id);
1477 break;
1478 default:
1479 snd_timer_user_zero_id(&id);
1482 mutex_unlock(&register_mutex);
1483 if (copy_to_user(_tid, &id, sizeof(*_tid)))
1484 return -EFAULT;
1485 return 0;
1488 static int snd_timer_user_ginfo(struct file *file,
1489 struct snd_timer_ginfo __user *_ginfo)
1491 struct snd_timer_ginfo *ginfo;
1492 struct snd_timer_id tid;
1493 struct snd_timer *t;
1494 struct list_head *p;
1495 int err = 0;
1497 ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1498 if (IS_ERR(ginfo))
1499 return PTR_ERR(ginfo);
1501 tid = ginfo->tid;
1502 memset(ginfo, 0, sizeof(*ginfo));
1503 ginfo->tid = tid;
1504 mutex_lock(&register_mutex);
1505 t = snd_timer_find(&tid);
1506 if (t != NULL) {
1507 ginfo->card = t->card ? t->card->number : -1;
1508 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1509 ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1510 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1511 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1512 ginfo->resolution = t->hw.resolution;
1513 if (t->hw.resolution_min > 0) {
1514 ginfo->resolution_min = t->hw.resolution_min;
1515 ginfo->resolution_max = t->hw.resolution_max;
1517 list_for_each(p, &t->open_list_head) {
1518 ginfo->clients++;
1520 } else {
1521 err = -ENODEV;
1523 mutex_unlock(&register_mutex);
1524 if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1525 err = -EFAULT;
1526 kfree(ginfo);
1527 return err;
1530 static int timer_set_gparams(struct snd_timer_gparams *gparams)
1532 struct snd_timer *t;
1533 int err;
1535 mutex_lock(&register_mutex);
1536 t = snd_timer_find(&gparams->tid);
1537 if (!t) {
1538 err = -ENODEV;
1539 goto _error;
1541 if (!list_empty(&t->open_list_head)) {
1542 err = -EBUSY;
1543 goto _error;
1545 if (!t->hw.set_period) {
1546 err = -ENOSYS;
1547 goto _error;
1549 err = t->hw.set_period(t, gparams->period_num, gparams->period_den);
1550 _error:
1551 mutex_unlock(&register_mutex);
1552 return err;
1555 static int snd_timer_user_gparams(struct file *file,
1556 struct snd_timer_gparams __user *_gparams)
1558 struct snd_timer_gparams gparams;
1560 if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1561 return -EFAULT;
1562 return timer_set_gparams(&gparams);
1565 static int snd_timer_user_gstatus(struct file *file,
1566 struct snd_timer_gstatus __user *_gstatus)
1568 struct snd_timer_gstatus gstatus;
1569 struct snd_timer_id tid;
1570 struct snd_timer *t;
1571 int err = 0;
1573 if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1574 return -EFAULT;
1575 tid = gstatus.tid;
1576 memset(&gstatus, 0, sizeof(gstatus));
1577 gstatus.tid = tid;
1578 mutex_lock(&register_mutex);
1579 t = snd_timer_find(&tid);
1580 if (t != NULL) {
1581 if (t->hw.c_resolution)
1582 gstatus.resolution = t->hw.c_resolution(t);
1583 else
1584 gstatus.resolution = t->hw.resolution;
1585 if (t->hw.precise_resolution) {
1586 t->hw.precise_resolution(t, &gstatus.resolution_num,
1587 &gstatus.resolution_den);
1588 } else {
1589 gstatus.resolution_num = gstatus.resolution;
1590 gstatus.resolution_den = 1000000000uL;
1592 } else {
1593 err = -ENODEV;
1595 mutex_unlock(&register_mutex);
1596 if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1597 err = -EFAULT;
1598 return err;
1601 static int snd_timer_user_tselect(struct file *file,
1602 struct snd_timer_select __user *_tselect)
1604 struct snd_timer_user *tu;
1605 struct snd_timer_select tselect;
1606 char str[32];
1607 int err = 0;
1609 tu = file->private_data;
1610 if (tu->timeri) {
1611 snd_timer_close(tu->timeri);
1612 tu->timeri = NULL;
1614 if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1615 err = -EFAULT;
1616 goto __err;
1618 sprintf(str, "application %i", current->pid);
1619 if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1620 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1621 err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1622 if (err < 0)
1623 goto __err;
1625 kfree(tu->queue);
1626 tu->queue = NULL;
1627 kfree(tu->tqueue);
1628 tu->tqueue = NULL;
1629 if (tu->tread) {
1630 tu->tqueue = kmalloc(tu->queue_size * sizeof(struct snd_timer_tread),
1631 GFP_KERNEL);
1632 if (tu->tqueue == NULL)
1633 err = -ENOMEM;
1634 } else {
1635 tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1636 GFP_KERNEL);
1637 if (tu->queue == NULL)
1638 err = -ENOMEM;
1641 if (err < 0) {
1642 snd_timer_close(tu->timeri);
1643 tu->timeri = NULL;
1644 } else {
1645 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1646 tu->timeri->callback = tu->tread
1647 ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1648 tu->timeri->ccallback = snd_timer_user_ccallback;
1649 tu->timeri->callback_data = (void *)tu;
1650 tu->timeri->disconnect = snd_timer_user_disconnect;
1653 __err:
1654 return err;
1657 static int snd_timer_user_info(struct file *file,
1658 struct snd_timer_info __user *_info)
1660 struct snd_timer_user *tu;
1661 struct snd_timer_info *info;
1662 struct snd_timer *t;
1663 int err = 0;
1665 tu = file->private_data;
1666 if (!tu->timeri)
1667 return -EBADFD;
1668 t = tu->timeri->timer;
1669 if (!t)
1670 return -EBADFD;
1672 info = kzalloc(sizeof(*info), GFP_KERNEL);
1673 if (! info)
1674 return -ENOMEM;
1675 info->card = t->card ? t->card->number : -1;
1676 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1677 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1678 strlcpy(info->id, t->id, sizeof(info->id));
1679 strlcpy(info->name, t->name, sizeof(info->name));
1680 info->resolution = t->hw.resolution;
1681 if (copy_to_user(_info, info, sizeof(*_info)))
1682 err = -EFAULT;
1683 kfree(info);
1684 return err;
1687 static int snd_timer_user_params(struct file *file,
1688 struct snd_timer_params __user *_params)
1690 struct snd_timer_user *tu;
1691 struct snd_timer_params params;
1692 struct snd_timer *t;
1693 struct snd_timer_read *tr;
1694 struct snd_timer_tread *ttr;
1695 int err;
1697 tu = file->private_data;
1698 if (!tu->timeri)
1699 return -EBADFD;
1700 t = tu->timeri->timer;
1701 if (!t)
1702 return -EBADFD;
1703 if (copy_from_user(&params, _params, sizeof(params)))
1704 return -EFAULT;
1705 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE) && params.ticks < 1) {
1706 err = -EINVAL;
1707 goto _end;
1709 if (params.queue_size > 0 &&
1710 (params.queue_size < 32 || params.queue_size > 1024)) {
1711 err = -EINVAL;
1712 goto _end;
1714 if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1715 (1<<SNDRV_TIMER_EVENT_TICK)|
1716 (1<<SNDRV_TIMER_EVENT_START)|
1717 (1<<SNDRV_TIMER_EVENT_STOP)|
1718 (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1719 (1<<SNDRV_TIMER_EVENT_PAUSE)|
1720 (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1721 (1<<SNDRV_TIMER_EVENT_RESUME)|
1722 (1<<SNDRV_TIMER_EVENT_MSTART)|
1723 (1<<SNDRV_TIMER_EVENT_MSTOP)|
1724 (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1725 (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1726 (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1727 (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1728 err = -EINVAL;
1729 goto _end;
1731 snd_timer_stop(tu->timeri);
1732 spin_lock_irq(&t->lock);
1733 tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1734 SNDRV_TIMER_IFLG_EXCLUSIVE|
1735 SNDRV_TIMER_IFLG_EARLY_EVENT);
1736 if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1737 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1738 if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1739 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1740 if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1741 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1742 spin_unlock_irq(&t->lock);
1743 if (params.queue_size > 0 &&
1744 (unsigned int)tu->queue_size != params.queue_size) {
1745 if (tu->tread) {
1746 ttr = kmalloc(params.queue_size * sizeof(*ttr),
1747 GFP_KERNEL);
1748 if (ttr) {
1749 kfree(tu->tqueue);
1750 tu->queue_size = params.queue_size;
1751 tu->tqueue = ttr;
1753 } else {
1754 tr = kmalloc(params.queue_size * sizeof(*tr),
1755 GFP_KERNEL);
1756 if (tr) {
1757 kfree(tu->queue);
1758 tu->queue_size = params.queue_size;
1759 tu->queue = tr;
1763 tu->qhead = tu->qtail = tu->qused = 0;
1764 if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1765 if (tu->tread) {
1766 struct snd_timer_tread tread;
1767 memset(&tread, 0, sizeof(tread));
1768 tread.event = SNDRV_TIMER_EVENT_EARLY;
1769 tread.tstamp.tv_sec = 0;
1770 tread.tstamp.tv_nsec = 0;
1771 tread.val = 0;
1772 snd_timer_user_append_to_tqueue(tu, &tread);
1773 } else {
1774 struct snd_timer_read *r = &tu->queue[0];
1775 r->resolution = 0;
1776 r->ticks = 0;
1777 tu->qused++;
1778 tu->qtail++;
1781 tu->filter = params.filter;
1782 tu->ticks = params.ticks;
1783 err = 0;
1784 _end:
1785 if (copy_to_user(_params, &params, sizeof(params)))
1786 return -EFAULT;
1787 return err;
1790 static int snd_timer_user_status(struct file *file,
1791 struct snd_timer_status __user *_status)
1793 struct snd_timer_user *tu;
1794 struct snd_timer_status status;
1796 tu = file->private_data;
1797 if (!tu->timeri)
1798 return -EBADFD;
1799 memset(&status, 0, sizeof(status));
1800 status.tstamp = tu->tstamp;
1801 status.resolution = snd_timer_resolution(tu->timeri);
1802 status.lost = tu->timeri->lost;
1803 status.overrun = tu->overrun;
1804 spin_lock_irq(&tu->qlock);
1805 status.queue = tu->qused;
1806 spin_unlock_irq(&tu->qlock);
1807 if (copy_to_user(_status, &status, sizeof(status)))
1808 return -EFAULT;
1809 return 0;
1812 static int snd_timer_user_start(struct file *file)
1814 int err;
1815 struct snd_timer_user *tu;
1817 tu = file->private_data;
1818 if (!tu->timeri)
1819 return -EBADFD;
1820 snd_timer_stop(tu->timeri);
1821 tu->timeri->lost = 0;
1822 tu->last_resolution = 0;
1823 return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1826 static int snd_timer_user_stop(struct file *file)
1828 int err;
1829 struct snd_timer_user *tu;
1831 tu = file->private_data;
1832 if (!tu->timeri)
1833 return -EBADFD;
1834 return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1837 static int snd_timer_user_continue(struct file *file)
1839 int err;
1840 struct snd_timer_user *tu;
1842 tu = file->private_data;
1843 if (!tu->timeri)
1844 return -EBADFD;
1845 /* start timer instead of continue if it's not used before */
1846 if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
1847 return snd_timer_user_start(file);
1848 tu->timeri->lost = 0;
1849 return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1852 static int snd_timer_user_pause(struct file *file)
1854 int err;
1855 struct snd_timer_user *tu;
1857 tu = file->private_data;
1858 if (!tu->timeri)
1859 return -EBADFD;
1860 return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1863 enum {
1864 SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1865 SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1866 SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1867 SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1870 static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1871 unsigned long arg)
1873 struct snd_timer_user *tu;
1874 void __user *argp = (void __user *)arg;
1875 int __user *p = argp;
1877 tu = file->private_data;
1878 switch (cmd) {
1879 case SNDRV_TIMER_IOCTL_PVERSION:
1880 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1881 case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1882 return snd_timer_user_next_device(argp);
1883 case SNDRV_TIMER_IOCTL_TREAD:
1885 int xarg;
1887 if (tu->timeri) /* too late */
1888 return -EBUSY;
1889 if (get_user(xarg, p))
1890 return -EFAULT;
1891 tu->tread = xarg ? 1 : 0;
1892 return 0;
1894 case SNDRV_TIMER_IOCTL_GINFO:
1895 return snd_timer_user_ginfo(file, argp);
1896 case SNDRV_TIMER_IOCTL_GPARAMS:
1897 return snd_timer_user_gparams(file, argp);
1898 case SNDRV_TIMER_IOCTL_GSTATUS:
1899 return snd_timer_user_gstatus(file, argp);
1900 case SNDRV_TIMER_IOCTL_SELECT:
1901 return snd_timer_user_tselect(file, argp);
1902 case SNDRV_TIMER_IOCTL_INFO:
1903 return snd_timer_user_info(file, argp);
1904 case SNDRV_TIMER_IOCTL_PARAMS:
1905 return snd_timer_user_params(file, argp);
1906 case SNDRV_TIMER_IOCTL_STATUS:
1907 return snd_timer_user_status(file, argp);
1908 case SNDRV_TIMER_IOCTL_START:
1909 case SNDRV_TIMER_IOCTL_START_OLD:
1910 return snd_timer_user_start(file);
1911 case SNDRV_TIMER_IOCTL_STOP:
1912 case SNDRV_TIMER_IOCTL_STOP_OLD:
1913 return snd_timer_user_stop(file);
1914 case SNDRV_TIMER_IOCTL_CONTINUE:
1915 case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1916 return snd_timer_user_continue(file);
1917 case SNDRV_TIMER_IOCTL_PAUSE:
1918 case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1919 return snd_timer_user_pause(file);
1921 return -ENOTTY;
1924 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1925 unsigned long arg)
1927 struct snd_timer_user *tu = file->private_data;
1928 long ret;
1930 mutex_lock(&tu->ioctl_lock);
1931 ret = __snd_timer_user_ioctl(file, cmd, arg);
1932 mutex_unlock(&tu->ioctl_lock);
1933 return ret;
1936 static int snd_timer_user_fasync(int fd, struct file * file, int on)
1938 struct snd_timer_user *tu;
1940 tu = file->private_data;
1941 return fasync_helper(fd, file, on, &tu->fasync);
1944 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
1945 size_t count, loff_t *offset)
1947 struct snd_timer_user *tu;
1948 long result = 0, unit;
1949 int qhead;
1950 int err = 0;
1952 tu = file->private_data;
1953 unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
1954 spin_lock_irq(&tu->qlock);
1955 while ((long)count - result >= unit) {
1956 while (!tu->qused) {
1957 wait_queue_t wait;
1959 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1960 err = -EAGAIN;
1961 goto _error;
1964 set_current_state(TASK_INTERRUPTIBLE);
1965 init_waitqueue_entry(&wait, current);
1966 add_wait_queue(&tu->qchange_sleep, &wait);
1968 spin_unlock_irq(&tu->qlock);
1969 schedule();
1970 spin_lock_irq(&tu->qlock);
1972 remove_wait_queue(&tu->qchange_sleep, &wait);
1974 if (tu->disconnected) {
1975 err = -ENODEV;
1976 goto _error;
1978 if (signal_pending(current)) {
1979 err = -ERESTARTSYS;
1980 goto _error;
1984 qhead = tu->qhead++;
1985 tu->qhead %= tu->queue_size;
1986 tu->qused--;
1987 spin_unlock_irq(&tu->qlock);
1989 mutex_lock(&tu->ioctl_lock);
1990 if (tu->tread) {
1991 if (copy_to_user(buffer, &tu->tqueue[qhead],
1992 sizeof(struct snd_timer_tread)))
1993 err = -EFAULT;
1994 } else {
1995 if (copy_to_user(buffer, &tu->queue[qhead],
1996 sizeof(struct snd_timer_read)))
1997 err = -EFAULT;
1999 mutex_unlock(&tu->ioctl_lock);
2001 spin_lock_irq(&tu->qlock);
2002 if (err < 0)
2003 goto _error;
2004 result += unit;
2005 buffer += unit;
2007 _error:
2008 spin_unlock_irq(&tu->qlock);
2009 return result > 0 ? result : err;
2012 static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
2014 unsigned int mask;
2015 struct snd_timer_user *tu;
2017 tu = file->private_data;
2019 poll_wait(file, &tu->qchange_sleep, wait);
2021 mask = 0;
2022 if (tu->qused)
2023 mask |= POLLIN | POLLRDNORM;
2024 if (tu->disconnected)
2025 mask |= POLLERR;
2027 return mask;
2030 #ifdef CONFIG_COMPAT
2031 #include "timer_compat.c"
2032 #else
2033 #define snd_timer_user_ioctl_compat NULL
2034 #endif
2036 static const struct file_operations snd_timer_f_ops =
2038 .owner = THIS_MODULE,
2039 .read = snd_timer_user_read,
2040 .open = snd_timer_user_open,
2041 .release = snd_timer_user_release,
2042 .llseek = no_llseek,
2043 .poll = snd_timer_user_poll,
2044 .unlocked_ioctl = snd_timer_user_ioctl,
2045 .compat_ioctl = snd_timer_user_ioctl_compat,
2046 .fasync = snd_timer_user_fasync,
2049 /* unregister the system timer */
2050 static void snd_timer_free_all(void)
2052 struct snd_timer *timer, *n;
2054 list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2055 snd_timer_free(timer);
2058 static struct device timer_dev;
2061 * ENTRY functions
2064 static int __init alsa_timer_init(void)
2066 int err;
2068 snd_device_initialize(&timer_dev, NULL);
2069 dev_set_name(&timer_dev, "timer");
2071 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2072 snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2073 "system timer");
2074 #endif
2076 err = snd_timer_register_system();
2077 if (err < 0) {
2078 pr_err("ALSA: unable to register system timer (%i)\n", err);
2079 put_device(&timer_dev);
2080 return err;
2083 err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2084 &snd_timer_f_ops, NULL, &timer_dev);
2085 if (err < 0) {
2086 pr_err("ALSA: unable to register timer device (%i)\n", err);
2087 snd_timer_free_all();
2088 put_device(&timer_dev);
2089 return err;
2092 snd_timer_proc_init();
2093 return 0;
2096 static void __exit alsa_timer_exit(void)
2098 snd_unregister_device(&timer_dev);
2099 snd_timer_free_all();
2100 put_device(&timer_dev);
2101 snd_timer_proc_done();
2102 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2103 snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2104 #endif
2107 module_init(alsa_timer_init)
2108 module_exit(alsa_timer_exit)
2110 EXPORT_SYMBOL(snd_timer_open);
2111 EXPORT_SYMBOL(snd_timer_close);
2112 EXPORT_SYMBOL(snd_timer_resolution);
2113 EXPORT_SYMBOL(snd_timer_start);
2114 EXPORT_SYMBOL(snd_timer_stop);
2115 EXPORT_SYMBOL(snd_timer_continue);
2116 EXPORT_SYMBOL(snd_timer_pause);
2117 EXPORT_SYMBOL(snd_timer_new);
2118 EXPORT_SYMBOL(snd_timer_notify);
2119 EXPORT_SYMBOL(snd_timer_global_new);
2120 EXPORT_SYMBOL(snd_timer_global_free);
2121 EXPORT_SYMBOL(snd_timer_global_register);
2122 EXPORT_SYMBOL(snd_timer_interrupt);