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1/*
2 * Timers abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
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.
10 *
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.
15 *
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
19 *
20 */
21
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>
37
38#if IS_ENABLED(CONFIG_SND_HRTIMER)
39#define DEFAULT_TIMER_LIMIT 4
40#elif IS_ENABLED(CONFIG_SND_RTCTIMER)
41#define DEFAULT_TIMER_LIMIT 2
42#else
43#define DEFAULT_TIMER_LIMIT 1
44#endif
45
46static int timer_limit = DEFAULT_TIMER_LIMIT;
47static int timer_tstamp_monotonic = 1;
48MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>");
49MODULE_DESCRIPTION("ALSA timer interface");
50MODULE_LICENSE("GPL");
51module_param(timer_limit, int, 0444);
52MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
53module_param(timer_tstamp_monotonic, int, 0444);
54MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
55
56MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
57MODULE_ALIAS("devname:snd/timer");
58
59struct snd_timer_user {
60 struct snd_timer_instance *timeri;
61 int tread; /* enhanced read with timestamps and events */
62 unsigned long ticks;
63 unsigned long overrun;
64 int qhead;
65 int qtail;
66 int qused;
67 int queue_size;
68 struct snd_timer_read *queue;
69 struct snd_timer_tread *tqueue;
70 spinlock_t qlock;
71 unsigned long last_resolution;
72 unsigned int filter;
73 struct timespec tstamp; /* trigger tstamp */
74 wait_queue_head_t qchange_sleep;
75 struct fasync_struct *fasync;
76 struct mutex tread_sem;
77};
78
79/* list of timers */
80static LIST_HEAD(snd_timer_list);
81
82/* list of slave instances */
83static LIST_HEAD(snd_timer_slave_list);
84
85/* lock for slave active lists */
86static DEFINE_SPINLOCK(slave_active_lock);
87
88static DEFINE_MUTEX(register_mutex);
89
90static int snd_timer_free(struct snd_timer *timer);
91static int snd_timer_dev_free(struct snd_device *device);
92static int snd_timer_dev_register(struct snd_device *device);
93static int snd_timer_dev_disconnect(struct snd_device *device);
94
95static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
96
97/*
98 * create a timer instance with the given owner string.
99 * when timer is not NULL, increments the module counter
100 */
101static struct snd_timer_instance *snd_timer_instance_new(char *owner,
102 struct snd_timer *timer)
103{
104 struct snd_timer_instance *timeri;
105 timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
106 if (timeri == NULL)
107 return NULL;
108 timeri->owner = kstrdup(owner, GFP_KERNEL);
109 if (! timeri->owner) {
110 kfree(timeri);
111 return NULL;
112 }
113 INIT_LIST_HEAD(&timeri->open_list);
114 INIT_LIST_HEAD(&timeri->active_list);
115 INIT_LIST_HEAD(&timeri->ack_list);
116 INIT_LIST_HEAD(&timeri->slave_list_head);
117 INIT_LIST_HEAD(&timeri->slave_active_head);
118
119 timeri->timer = timer;
120 if (timer && !try_module_get(timer->module)) {
121 kfree(timeri->owner);
122 kfree(timeri);
123 return NULL;
124 }
125
126 return timeri;
127}
128
129/*
130 * find a timer instance from the given timer id
131 */
132static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
133{
134 struct snd_timer *timer = NULL;
135
136 list_for_each_entry(timer, &snd_timer_list, device_list) {
137 if (timer->tmr_class != tid->dev_class)
138 continue;
139 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
140 timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
141 (timer->card == NULL ||
142 timer->card->number != tid->card))
143 continue;
144 if (timer->tmr_device != tid->device)
145 continue;
146 if (timer->tmr_subdevice != tid->subdevice)
147 continue;
148 return timer;
149 }
150 return NULL;
151}
152
153#ifdef CONFIG_MODULES
154
155static void snd_timer_request(struct snd_timer_id *tid)
156{
157 switch (tid->dev_class) {
158 case SNDRV_TIMER_CLASS_GLOBAL:
159 if (tid->device < timer_limit)
160 request_module("snd-timer-%i", tid->device);
161 break;
162 case SNDRV_TIMER_CLASS_CARD:
163 case SNDRV_TIMER_CLASS_PCM:
164 if (tid->card < snd_ecards_limit)
165 request_module("snd-card-%i", tid->card);
166 break;
167 default:
168 break;
169 }
170}
171
172#endif
173
174/*
175 * look for a master instance matching with the slave id of the given slave.
176 * when found, relink the open_link of the slave.
177 *
178 * call this with register_mutex down.
179 */
180static void snd_timer_check_slave(struct snd_timer_instance *slave)
181{
182 struct snd_timer *timer;
183 struct snd_timer_instance *master;
184
185 /* FIXME: it's really dumb to look up all entries.. */
186 list_for_each_entry(timer, &snd_timer_list, device_list) {
187 list_for_each_entry(master, &timer->open_list_head, open_list) {
188 if (slave->slave_class == master->slave_class &&
189 slave->slave_id == master->slave_id) {
190 list_move_tail(&slave->open_list,
191 &master->slave_list_head);
192 spin_lock_irq(&slave_active_lock);
193 slave->master = master;
194 slave->timer = master->timer;
195 spin_unlock_irq(&slave_active_lock);
196 return;
197 }
198 }
199 }
200}
201
202/*
203 * look for slave instances matching with the slave id of the given master.
204 * when found, relink the open_link of slaves.
205 *
206 * call this with register_mutex down.
207 */
208static void snd_timer_check_master(struct snd_timer_instance *master)
209{
210 struct snd_timer_instance *slave, *tmp;
211
212 /* check all pending slaves */
213 list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
214 if (slave->slave_class == master->slave_class &&
215 slave->slave_id == master->slave_id) {
216 list_move_tail(&slave->open_list, &master->slave_list_head);
217 spin_lock_irq(&slave_active_lock);
218 slave->master = master;
219 slave->timer = master->timer;
220 if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
221 list_add_tail(&slave->active_list,
222 &master->slave_active_head);
223 spin_unlock_irq(&slave_active_lock);
224 }
225 }
226}
227
228/*
229 * open a timer instance
230 * when opening a master, the slave id must be here given.
231 */
232int snd_timer_open(struct snd_timer_instance **ti,
233 char *owner, struct snd_timer_id *tid,
234 unsigned int slave_id)
235{
236 struct snd_timer *timer;
237 struct snd_timer_instance *timeri = NULL;
238
239 if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
240 /* open a slave instance */
241 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
242 tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
243 pr_debug("ALSA: timer: invalid slave class %i\n",
244 tid->dev_sclass);
245 return -EINVAL;
246 }
247 mutex_lock(®ister_mutex);
248 timeri = snd_timer_instance_new(owner, NULL);
249 if (!timeri) {
250 mutex_unlock(®ister_mutex);
251 return -ENOMEM;
252 }
253 timeri->slave_class = tid->dev_sclass;
254 timeri->slave_id = tid->device;
255 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
256 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
257 snd_timer_check_slave(timeri);
258 mutex_unlock(®ister_mutex);
259 *ti = timeri;
260 return 0;
261 }
262
263 /* open a master instance */
264 mutex_lock(®ister_mutex);
265 timer = snd_timer_find(tid);
266#ifdef CONFIG_MODULES
267 if (!timer) {
268 mutex_unlock(®ister_mutex);
269 snd_timer_request(tid);
270 mutex_lock(®ister_mutex);
271 timer = snd_timer_find(tid);
272 }
273#endif
274 if (!timer) {
275 mutex_unlock(®ister_mutex);
276 return -ENODEV;
277 }
278 if (!list_empty(&timer->open_list_head)) {
279 timeri = list_entry(timer->open_list_head.next,
280 struct snd_timer_instance, open_list);
281 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
282 mutex_unlock(®ister_mutex);
283 return -EBUSY;
284 }
285 }
286 timeri = snd_timer_instance_new(owner, timer);
287 if (!timeri) {
288 mutex_unlock(®ister_mutex);
289 return -ENOMEM;
290 }
291 timeri->slave_class = tid->dev_sclass;
292 timeri->slave_id = slave_id;
293 if (list_empty(&timer->open_list_head) && timer->hw.open)
294 timer->hw.open(timer);
295 list_add_tail(&timeri->open_list, &timer->open_list_head);
296 snd_timer_check_master(timeri);
297 mutex_unlock(®ister_mutex);
298 *ti = timeri;
299 return 0;
300}
301
302static int _snd_timer_stop(struct snd_timer_instance *timeri,
303 int keep_flag, int event);
304
305/*
306 * close a timer instance
307 */
308int snd_timer_close(struct snd_timer_instance *timeri)
309{
310 struct snd_timer *timer = NULL;
311 struct snd_timer_instance *slave, *tmp;
312
313 if (snd_BUG_ON(!timeri))
314 return -ENXIO;
315
316 /* force to stop the timer */
317 snd_timer_stop(timeri);
318
319 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
320 /* wait, until the active callback is finished */
321 spin_lock_irq(&slave_active_lock);
322 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
323 spin_unlock_irq(&slave_active_lock);
324 udelay(10);
325 spin_lock_irq(&slave_active_lock);
326 }
327 spin_unlock_irq(&slave_active_lock);
328 mutex_lock(®ister_mutex);
329 list_del(&timeri->open_list);
330 mutex_unlock(®ister_mutex);
331 } else {
332 timer = timeri->timer;
333 if (snd_BUG_ON(!timer))
334 goto out;
335 /* wait, until the active callback is finished */
336 spin_lock_irq(&timer->lock);
337 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
338 spin_unlock_irq(&timer->lock);
339 udelay(10);
340 spin_lock_irq(&timer->lock);
341 }
342 spin_unlock_irq(&timer->lock);
343 mutex_lock(®ister_mutex);
344 list_del(&timeri->open_list);
345 if (timer && list_empty(&timer->open_list_head) &&
346 timer->hw.close)
347 timer->hw.close(timer);
348 /* remove slave links */
349 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
350 open_list) {
351 spin_lock_irq(&slave_active_lock);
352 _snd_timer_stop(slave, 1, SNDRV_TIMER_EVENT_RESOLUTION);
353 list_move_tail(&slave->open_list, &snd_timer_slave_list);
354 slave->master = NULL;
355 slave->timer = NULL;
356 spin_unlock_irq(&slave_active_lock);
357 }
358 mutex_unlock(®ister_mutex);
359 }
360 out:
361 if (timeri->private_free)
362 timeri->private_free(timeri);
363 kfree(timeri->owner);
364 kfree(timeri);
365 if (timer)
366 module_put(timer->module);
367 return 0;
368}
369
370unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
371{
372 struct snd_timer * timer;
373
374 if (timeri == NULL)
375 return 0;
376 if ((timer = timeri->timer) != NULL) {
377 if (timer->hw.c_resolution)
378 return timer->hw.c_resolution(timer);
379 return timer->hw.resolution;
380 }
381 return 0;
382}
383
384static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
385{
386 struct snd_timer *timer;
387 unsigned long flags;
388 unsigned long resolution = 0;
389 struct snd_timer_instance *ts;
390 struct timespec tstamp;
391
392 if (timer_tstamp_monotonic)
393 do_posix_clock_monotonic_gettime(&tstamp);
394 else
395 getnstimeofday(&tstamp);
396 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
397 event > SNDRV_TIMER_EVENT_PAUSE))
398 return;
399 if (event == SNDRV_TIMER_EVENT_START ||
400 event == SNDRV_TIMER_EVENT_CONTINUE)
401 resolution = snd_timer_resolution(ti);
402 if (ti->ccallback)
403 ti->ccallback(ti, event, &tstamp, resolution);
404 if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
405 return;
406 timer = ti->timer;
407 if (timer == NULL)
408 return;
409 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
410 return;
411 spin_lock_irqsave(&timer->lock, flags);
412 list_for_each_entry(ts, &ti->slave_active_head, active_list)
413 if (ts->ccallback)
414 ts->ccallback(ti, event + 100, &tstamp, resolution);
415 spin_unlock_irqrestore(&timer->lock, flags);
416}
417
418static int snd_timer_start1(struct snd_timer *timer, struct snd_timer_instance *timeri,
419 unsigned long sticks)
420{
421 list_move_tail(&timeri->active_list, &timer->active_list_head);
422 if (timer->running) {
423 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
424 goto __start_now;
425 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
426 timeri->flags |= SNDRV_TIMER_IFLG_START;
427 return 1; /* delayed start */
428 } else {
429 timer->sticks = sticks;
430 timer->hw.start(timer);
431 __start_now:
432 timer->running++;
433 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
434 return 0;
435 }
436}
437
438static int snd_timer_start_slave(struct snd_timer_instance *timeri)
439{
440 unsigned long flags;
441
442 spin_lock_irqsave(&slave_active_lock, flags);
443 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
444 if (timeri->master)
445 list_add_tail(&timeri->active_list,
446 &timeri->master->slave_active_head);
447 spin_unlock_irqrestore(&slave_active_lock, flags);
448 return 1; /* delayed start */
449}
450
451/*
452 * start the timer instance
453 */
454int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
455{
456 struct snd_timer *timer;
457 int result = -EINVAL;
458 unsigned long flags;
459
460 if (timeri == NULL || ticks < 1)
461 return -EINVAL;
462 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
463 result = snd_timer_start_slave(timeri);
464 snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
465 return result;
466 }
467 timer = timeri->timer;
468 if (timer == NULL)
469 return -EINVAL;
470 spin_lock_irqsave(&timer->lock, flags);
471 timeri->ticks = timeri->cticks = ticks;
472 timeri->pticks = 0;
473 result = snd_timer_start1(timer, timeri, ticks);
474 spin_unlock_irqrestore(&timer->lock, flags);
475 snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
476 return result;
477}
478
479static int _snd_timer_stop(struct snd_timer_instance * timeri,
480 int keep_flag, int event)
481{
482 struct snd_timer *timer;
483 unsigned long flags;
484
485 if (snd_BUG_ON(!timeri))
486 return -ENXIO;
487
488 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
489 if (!keep_flag) {
490 spin_lock_irqsave(&slave_active_lock, flags);
491 timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
492 spin_unlock_irqrestore(&slave_active_lock, flags);
493 }
494 goto __end;
495 }
496 timer = timeri->timer;
497 if (!timer)
498 return -EINVAL;
499 spin_lock_irqsave(&timer->lock, flags);
500 list_del_init(&timeri->ack_list);
501 list_del_init(&timeri->active_list);
502 if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
503 !(--timer->running)) {
504 timer->hw.stop(timer);
505 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
506 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
507 snd_timer_reschedule(timer, 0);
508 if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
509 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
510 timer->hw.start(timer);
511 }
512 }
513 }
514 if (!keep_flag)
515 timeri->flags &=
516 ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
517 spin_unlock_irqrestore(&timer->lock, flags);
518 __end:
519 if (event != SNDRV_TIMER_EVENT_RESOLUTION)
520 snd_timer_notify1(timeri, event);
521 return 0;
522}
523
524/*
525 * stop the timer instance.
526 *
527 * do not call this from the timer callback!
528 */
529int snd_timer_stop(struct snd_timer_instance *timeri)
530{
531 struct snd_timer *timer;
532 unsigned long flags;
533 int err;
534
535 err = _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_STOP);
536 if (err < 0)
537 return err;
538 timer = timeri->timer;
539 if (!timer)
540 return -EINVAL;
541 spin_lock_irqsave(&timer->lock, flags);
542 timeri->cticks = timeri->ticks;
543 timeri->pticks = 0;
544 spin_unlock_irqrestore(&timer->lock, flags);
545 return 0;
546}
547
548/*
549 * start again.. the tick is kept.
550 */
551int snd_timer_continue(struct snd_timer_instance *timeri)
552{
553 struct snd_timer *timer;
554 int result = -EINVAL;
555 unsigned long flags;
556
557 if (timeri == NULL)
558 return result;
559 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
560 return snd_timer_start_slave(timeri);
561 timer = timeri->timer;
562 if (! timer)
563 return -EINVAL;
564 spin_lock_irqsave(&timer->lock, flags);
565 if (!timeri->cticks)
566 timeri->cticks = 1;
567 timeri->pticks = 0;
568 result = snd_timer_start1(timer, timeri, timer->sticks);
569 spin_unlock_irqrestore(&timer->lock, flags);
570 snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_CONTINUE);
571 return result;
572}
573
574/*
575 * pause.. remember the ticks left
576 */
577int snd_timer_pause(struct snd_timer_instance * timeri)
578{
579 return _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_PAUSE);
580}
581
582/*
583 * reschedule the timer
584 *
585 * start pending instances and check the scheduling ticks.
586 * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
587 */
588static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
589{
590 struct snd_timer_instance *ti;
591 unsigned long ticks = ~0UL;
592
593 list_for_each_entry(ti, &timer->active_list_head, active_list) {
594 if (ti->flags & SNDRV_TIMER_IFLG_START) {
595 ti->flags &= ~SNDRV_TIMER_IFLG_START;
596 ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
597 timer->running++;
598 }
599 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
600 if (ticks > ti->cticks)
601 ticks = ti->cticks;
602 }
603 }
604 if (ticks == ~0UL) {
605 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
606 return;
607 }
608 if (ticks > timer->hw.ticks)
609 ticks = timer->hw.ticks;
610 if (ticks_left != ticks)
611 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
612 timer->sticks = ticks;
613}
614
615/*
616 * timer tasklet
617 *
618 */
619static void snd_timer_tasklet(unsigned long arg)
620{
621 struct snd_timer *timer = (struct snd_timer *) arg;
622 struct snd_timer_instance *ti;
623 struct list_head *p;
624 unsigned long resolution, ticks;
625 unsigned long flags;
626
627 spin_lock_irqsave(&timer->lock, flags);
628 /* now process all callbacks */
629 while (!list_empty(&timer->sack_list_head)) {
630 p = timer->sack_list_head.next; /* get first item */
631 ti = list_entry(p, struct snd_timer_instance, ack_list);
632
633 /* remove from ack_list and make empty */
634 list_del_init(p);
635
636 ticks = ti->pticks;
637 ti->pticks = 0;
638 resolution = ti->resolution;
639
640 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
641 spin_unlock(&timer->lock);
642 if (ti->callback)
643 ti->callback(ti, resolution, ticks);
644 spin_lock(&timer->lock);
645 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
646 }
647 spin_unlock_irqrestore(&timer->lock, flags);
648}
649
650/*
651 * timer interrupt
652 *
653 * ticks_left is usually equal to timer->sticks.
654 *
655 */
656void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
657{
658 struct snd_timer_instance *ti, *ts, *tmp;
659 unsigned long resolution, ticks;
660 struct list_head *p, *ack_list_head;
661 unsigned long flags;
662 int use_tasklet = 0;
663
664 if (timer == NULL)
665 return;
666
667 spin_lock_irqsave(&timer->lock, flags);
668
669 /* remember the current resolution */
670 if (timer->hw.c_resolution)
671 resolution = timer->hw.c_resolution(timer);
672 else
673 resolution = timer->hw.resolution;
674
675 /* loop for all active instances
676 * Here we cannot use list_for_each_entry because the active_list of a
677 * processed instance is relinked to done_list_head before the callback
678 * is called.
679 */
680 list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
681 active_list) {
682 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
683 continue;
684 ti->pticks += ticks_left;
685 ti->resolution = resolution;
686 if (ti->cticks < ticks_left)
687 ti->cticks = 0;
688 else
689 ti->cticks -= ticks_left;
690 if (ti->cticks) /* not expired */
691 continue;
692 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
693 ti->cticks = ti->ticks;
694 } else {
695 ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
696 if (--timer->running)
697 list_del(&ti->active_list);
698 }
699 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
700 (ti->flags & SNDRV_TIMER_IFLG_FAST))
701 ack_list_head = &timer->ack_list_head;
702 else
703 ack_list_head = &timer->sack_list_head;
704 if (list_empty(&ti->ack_list))
705 list_add_tail(&ti->ack_list, ack_list_head);
706 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
707 ts->pticks = ti->pticks;
708 ts->resolution = resolution;
709 if (list_empty(&ts->ack_list))
710 list_add_tail(&ts->ack_list, ack_list_head);
711 }
712 }
713 if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
714 snd_timer_reschedule(timer, timer->sticks);
715 if (timer->running) {
716 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
717 timer->hw.stop(timer);
718 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
719 }
720 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
721 (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
722 /* restart timer */
723 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
724 timer->hw.start(timer);
725 }
726 } else {
727 timer->hw.stop(timer);
728 }
729
730 /* now process all fast callbacks */
731 while (!list_empty(&timer->ack_list_head)) {
732 p = timer->ack_list_head.next; /* get first item */
733 ti = list_entry(p, struct snd_timer_instance, ack_list);
734
735 /* remove from ack_list and make empty */
736 list_del_init(p);
737
738 ticks = ti->pticks;
739 ti->pticks = 0;
740
741 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
742 spin_unlock(&timer->lock);
743 if (ti->callback)
744 ti->callback(ti, resolution, ticks);
745 spin_lock(&timer->lock);
746 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
747 }
748
749 /* do we have any slow callbacks? */
750 use_tasklet = !list_empty(&timer->sack_list_head);
751 spin_unlock_irqrestore(&timer->lock, flags);
752
753 if (use_tasklet)
754 tasklet_schedule(&timer->task_queue);
755}
756
757/*
758
759 */
760
761int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
762 struct snd_timer **rtimer)
763{
764 struct snd_timer *timer;
765 int err;
766 static struct snd_device_ops ops = {
767 .dev_free = snd_timer_dev_free,
768 .dev_register = snd_timer_dev_register,
769 .dev_disconnect = snd_timer_dev_disconnect,
770 };
771
772 if (snd_BUG_ON(!tid))
773 return -EINVAL;
774 if (rtimer)
775 *rtimer = NULL;
776 timer = kzalloc(sizeof(*timer), GFP_KERNEL);
777 if (timer == NULL) {
778 pr_err("ALSA: timer: cannot allocate\n");
779 return -ENOMEM;
780 }
781 timer->tmr_class = tid->dev_class;
782 timer->card = card;
783 timer->tmr_device = tid->device;
784 timer->tmr_subdevice = tid->subdevice;
785 if (id)
786 strlcpy(timer->id, id, sizeof(timer->id));
787 INIT_LIST_HEAD(&timer->device_list);
788 INIT_LIST_HEAD(&timer->open_list_head);
789 INIT_LIST_HEAD(&timer->active_list_head);
790 INIT_LIST_HEAD(&timer->ack_list_head);
791 INIT_LIST_HEAD(&timer->sack_list_head);
792 spin_lock_init(&timer->lock);
793 tasklet_init(&timer->task_queue, snd_timer_tasklet,
794 (unsigned long)timer);
795 if (card != NULL) {
796 timer->module = card->module;
797 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
798 if (err < 0) {
799 snd_timer_free(timer);
800 return err;
801 }
802 }
803 if (rtimer)
804 *rtimer = timer;
805 return 0;
806}
807
808static int snd_timer_free(struct snd_timer *timer)
809{
810 if (!timer)
811 return 0;
812
813 mutex_lock(®ister_mutex);
814 if (! list_empty(&timer->open_list_head)) {
815 struct list_head *p, *n;
816 struct snd_timer_instance *ti;
817 pr_warn("ALSA: timer %p is busy?\n", timer);
818 list_for_each_safe(p, n, &timer->open_list_head) {
819 list_del_init(p);
820 ti = list_entry(p, struct snd_timer_instance, open_list);
821 ti->timer = NULL;
822 }
823 }
824 list_del(&timer->device_list);
825 mutex_unlock(®ister_mutex);
826
827 if (timer->private_free)
828 timer->private_free(timer);
829 kfree(timer);
830 return 0;
831}
832
833static int snd_timer_dev_free(struct snd_device *device)
834{
835 struct snd_timer *timer = device->device_data;
836 return snd_timer_free(timer);
837}
838
839static int snd_timer_dev_register(struct snd_device *dev)
840{
841 struct snd_timer *timer = dev->device_data;
842 struct snd_timer *timer1;
843
844 if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
845 return -ENXIO;
846 if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
847 !timer->hw.resolution && timer->hw.c_resolution == NULL)
848 return -EINVAL;
849
850 mutex_lock(®ister_mutex);
851 list_for_each_entry(timer1, &snd_timer_list, device_list) {
852 if (timer1->tmr_class > timer->tmr_class)
853 break;
854 if (timer1->tmr_class < timer->tmr_class)
855 continue;
856 if (timer1->card && timer->card) {
857 if (timer1->card->number > timer->card->number)
858 break;
859 if (timer1->card->number < timer->card->number)
860 continue;
861 }
862 if (timer1->tmr_device > timer->tmr_device)
863 break;
864 if (timer1->tmr_device < timer->tmr_device)
865 continue;
866 if (timer1->tmr_subdevice > timer->tmr_subdevice)
867 break;
868 if (timer1->tmr_subdevice < timer->tmr_subdevice)
869 continue;
870 /* conflicts.. */
871 mutex_unlock(®ister_mutex);
872 return -EBUSY;
873 }
874 list_add_tail(&timer->device_list, &timer1->device_list);
875 mutex_unlock(®ister_mutex);
876 return 0;
877}
878
879static int snd_timer_dev_disconnect(struct snd_device *device)
880{
881 struct snd_timer *timer = device->device_data;
882 mutex_lock(®ister_mutex);
883 list_del_init(&timer->device_list);
884 mutex_unlock(®ister_mutex);
885 return 0;
886}
887
888void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
889{
890 unsigned long flags;
891 unsigned long resolution = 0;
892 struct snd_timer_instance *ti, *ts;
893
894 if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
895 return;
896 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
897 event > SNDRV_TIMER_EVENT_MRESUME))
898 return;
899 spin_lock_irqsave(&timer->lock, flags);
900 if (event == SNDRV_TIMER_EVENT_MSTART ||
901 event == SNDRV_TIMER_EVENT_MCONTINUE ||
902 event == SNDRV_TIMER_EVENT_MRESUME) {
903 if (timer->hw.c_resolution)
904 resolution = timer->hw.c_resolution(timer);
905 else
906 resolution = timer->hw.resolution;
907 }
908 list_for_each_entry(ti, &timer->active_list_head, active_list) {
909 if (ti->ccallback)
910 ti->ccallback(ti, event, tstamp, resolution);
911 list_for_each_entry(ts, &ti->slave_active_head, active_list)
912 if (ts->ccallback)
913 ts->ccallback(ts, event, tstamp, resolution);
914 }
915 spin_unlock_irqrestore(&timer->lock, flags);
916}
917
918/*
919 * exported functions for global timers
920 */
921int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
922{
923 struct snd_timer_id tid;
924
925 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
926 tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
927 tid.card = -1;
928 tid.device = device;
929 tid.subdevice = 0;
930 return snd_timer_new(NULL, id, &tid, rtimer);
931}
932
933int snd_timer_global_free(struct snd_timer *timer)
934{
935 return snd_timer_free(timer);
936}
937
938int snd_timer_global_register(struct snd_timer *timer)
939{
940 struct snd_device dev;
941
942 memset(&dev, 0, sizeof(dev));
943 dev.device_data = timer;
944 return snd_timer_dev_register(&dev);
945}
946
947/*
948 * System timer
949 */
950
951struct snd_timer_system_private {
952 struct timer_list tlist;
953 unsigned long last_expires;
954 unsigned long last_jiffies;
955 unsigned long correction;
956};
957
958static void snd_timer_s_function(unsigned long data)
959{
960 struct snd_timer *timer = (struct snd_timer *)data;
961 struct snd_timer_system_private *priv = timer->private_data;
962 unsigned long jiff = jiffies;
963 if (time_after(jiff, priv->last_expires))
964 priv->correction += (long)jiff - (long)priv->last_expires;
965 snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
966}
967
968static int snd_timer_s_start(struct snd_timer * timer)
969{
970 struct snd_timer_system_private *priv;
971 unsigned long njiff;
972
973 priv = (struct snd_timer_system_private *) timer->private_data;
974 njiff = (priv->last_jiffies = jiffies);
975 if (priv->correction > timer->sticks - 1) {
976 priv->correction -= timer->sticks - 1;
977 njiff++;
978 } else {
979 njiff += timer->sticks - priv->correction;
980 priv->correction = 0;
981 }
982 priv->last_expires = priv->tlist.expires = njiff;
983 add_timer(&priv->tlist);
984 return 0;
985}
986
987static int snd_timer_s_stop(struct snd_timer * timer)
988{
989 struct snd_timer_system_private *priv;
990 unsigned long jiff;
991
992 priv = (struct snd_timer_system_private *) timer->private_data;
993 del_timer(&priv->tlist);
994 jiff = jiffies;
995 if (time_before(jiff, priv->last_expires))
996 timer->sticks = priv->last_expires - jiff;
997 else
998 timer->sticks = 1;
999 priv->correction = 0;
1000 return 0;
1001}
1002
1003static struct snd_timer_hardware snd_timer_system =
1004{
1005 .flags = SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
1006 .resolution = 1000000000L / HZ,
1007 .ticks = 10000000L,
1008 .start = snd_timer_s_start,
1009 .stop = snd_timer_s_stop
1010};
1011
1012static void snd_timer_free_system(struct snd_timer *timer)
1013{
1014 kfree(timer->private_data);
1015}
1016
1017static int snd_timer_register_system(void)
1018{
1019 struct snd_timer *timer;
1020 struct snd_timer_system_private *priv;
1021 int err;
1022
1023 err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1024 if (err < 0)
1025 return err;
1026 strcpy(timer->name, "system timer");
1027 timer->hw = snd_timer_system;
1028 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1029 if (priv == NULL) {
1030 snd_timer_free(timer);
1031 return -ENOMEM;
1032 }
1033 init_timer(&priv->tlist);
1034 priv->tlist.function = snd_timer_s_function;
1035 priv->tlist.data = (unsigned long) timer;
1036 timer->private_data = priv;
1037 timer->private_free = snd_timer_free_system;
1038 return snd_timer_global_register(timer);
1039}
1040
1041#ifdef CONFIG_PROC_FS
1042/*
1043 * Info interface
1044 */
1045
1046static void snd_timer_proc_read(struct snd_info_entry *entry,
1047 struct snd_info_buffer *buffer)
1048{
1049 struct snd_timer *timer;
1050 struct snd_timer_instance *ti;
1051
1052 mutex_lock(®ister_mutex);
1053 list_for_each_entry(timer, &snd_timer_list, device_list) {
1054 switch (timer->tmr_class) {
1055 case SNDRV_TIMER_CLASS_GLOBAL:
1056 snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1057 break;
1058 case SNDRV_TIMER_CLASS_CARD:
1059 snd_iprintf(buffer, "C%i-%i: ",
1060 timer->card->number, timer->tmr_device);
1061 break;
1062 case SNDRV_TIMER_CLASS_PCM:
1063 snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1064 timer->tmr_device, timer->tmr_subdevice);
1065 break;
1066 default:
1067 snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1068 timer->card ? timer->card->number : -1,
1069 timer->tmr_device, timer->tmr_subdevice);
1070 }
1071 snd_iprintf(buffer, "%s :", timer->name);
1072 if (timer->hw.resolution)
1073 snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1074 timer->hw.resolution / 1000,
1075 timer->hw.resolution % 1000,
1076 timer->hw.ticks);
1077 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1078 snd_iprintf(buffer, " SLAVE");
1079 snd_iprintf(buffer, "\n");
1080 list_for_each_entry(ti, &timer->open_list_head, open_list)
1081 snd_iprintf(buffer, " Client %s : %s\n",
1082 ti->owner ? ti->owner : "unknown",
1083 ti->flags & (SNDRV_TIMER_IFLG_START |
1084 SNDRV_TIMER_IFLG_RUNNING)
1085 ? "running" : "stopped");
1086 }
1087 mutex_unlock(®ister_mutex);
1088}
1089
1090static struct snd_info_entry *snd_timer_proc_entry;
1091
1092static void __init snd_timer_proc_init(void)
1093{
1094 struct snd_info_entry *entry;
1095
1096 entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1097 if (entry != NULL) {
1098 entry->c.text.read = snd_timer_proc_read;
1099 if (snd_info_register(entry) < 0) {
1100 snd_info_free_entry(entry);
1101 entry = NULL;
1102 }
1103 }
1104 snd_timer_proc_entry = entry;
1105}
1106
1107static void __exit snd_timer_proc_done(void)
1108{
1109 snd_info_free_entry(snd_timer_proc_entry);
1110}
1111#else /* !CONFIG_PROC_FS */
1112#define snd_timer_proc_init()
1113#define snd_timer_proc_done()
1114#endif
1115
1116/*
1117 * USER SPACE interface
1118 */
1119
1120static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1121 unsigned long resolution,
1122 unsigned long ticks)
1123{
1124 struct snd_timer_user *tu = timeri->callback_data;
1125 struct snd_timer_read *r;
1126 int prev;
1127
1128 spin_lock(&tu->qlock);
1129 if (tu->qused > 0) {
1130 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1131 r = &tu->queue[prev];
1132 if (r->resolution == resolution) {
1133 r->ticks += ticks;
1134 goto __wake;
1135 }
1136 }
1137 if (tu->qused >= tu->queue_size) {
1138 tu->overrun++;
1139 } else {
1140 r = &tu->queue[tu->qtail++];
1141 tu->qtail %= tu->queue_size;
1142 r->resolution = resolution;
1143 r->ticks = ticks;
1144 tu->qused++;
1145 }
1146 __wake:
1147 spin_unlock(&tu->qlock);
1148 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1149 wake_up(&tu->qchange_sleep);
1150}
1151
1152static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1153 struct snd_timer_tread *tread)
1154{
1155 if (tu->qused >= tu->queue_size) {
1156 tu->overrun++;
1157 } else {
1158 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1159 tu->qtail %= tu->queue_size;
1160 tu->qused++;
1161 }
1162}
1163
1164static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1165 int event,
1166 struct timespec *tstamp,
1167 unsigned long resolution)
1168{
1169 struct snd_timer_user *tu = timeri->callback_data;
1170 struct snd_timer_tread r1;
1171 unsigned long flags;
1172
1173 if (event >= SNDRV_TIMER_EVENT_START &&
1174 event <= SNDRV_TIMER_EVENT_PAUSE)
1175 tu->tstamp = *tstamp;
1176 if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1177 return;
1178 r1.event = event;
1179 r1.tstamp = *tstamp;
1180 r1.val = resolution;
1181 spin_lock_irqsave(&tu->qlock, flags);
1182 snd_timer_user_append_to_tqueue(tu, &r1);
1183 spin_unlock_irqrestore(&tu->qlock, flags);
1184 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1185 wake_up(&tu->qchange_sleep);
1186}
1187
1188static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1189 unsigned long resolution,
1190 unsigned long ticks)
1191{
1192 struct snd_timer_user *tu = timeri->callback_data;
1193 struct snd_timer_tread *r, r1;
1194 struct timespec tstamp;
1195 int prev, append = 0;
1196
1197 memset(&tstamp, 0, sizeof(tstamp));
1198 spin_lock(&tu->qlock);
1199 if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1200 (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1201 spin_unlock(&tu->qlock);
1202 return;
1203 }
1204 if (tu->last_resolution != resolution || ticks > 0) {
1205 if (timer_tstamp_monotonic)
1206 do_posix_clock_monotonic_gettime(&tstamp);
1207 else
1208 getnstimeofday(&tstamp);
1209 }
1210 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1211 tu->last_resolution != resolution) {
1212 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1213 r1.tstamp = tstamp;
1214 r1.val = resolution;
1215 snd_timer_user_append_to_tqueue(tu, &r1);
1216 tu->last_resolution = resolution;
1217 append++;
1218 }
1219 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1220 goto __wake;
1221 if (ticks == 0)
1222 goto __wake;
1223 if (tu->qused > 0) {
1224 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1225 r = &tu->tqueue[prev];
1226 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1227 r->tstamp = tstamp;
1228 r->val += ticks;
1229 append++;
1230 goto __wake;
1231 }
1232 }
1233 r1.event = SNDRV_TIMER_EVENT_TICK;
1234 r1.tstamp = tstamp;
1235 r1.val = ticks;
1236 snd_timer_user_append_to_tqueue(tu, &r1);
1237 append++;
1238 __wake:
1239 spin_unlock(&tu->qlock);
1240 if (append == 0)
1241 return;
1242 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1243 wake_up(&tu->qchange_sleep);
1244}
1245
1246static int snd_timer_user_open(struct inode *inode, struct file *file)
1247{
1248 struct snd_timer_user *tu;
1249 int err;
1250
1251 err = nonseekable_open(inode, file);
1252 if (err < 0)
1253 return err;
1254
1255 tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1256 if (tu == NULL)
1257 return -ENOMEM;
1258 spin_lock_init(&tu->qlock);
1259 init_waitqueue_head(&tu->qchange_sleep);
1260 mutex_init(&tu->tread_sem);
1261 tu->ticks = 1;
1262 tu->queue_size = 128;
1263 tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1264 GFP_KERNEL);
1265 if (tu->queue == NULL) {
1266 kfree(tu);
1267 return -ENOMEM;
1268 }
1269 file->private_data = tu;
1270 return 0;
1271}
1272
1273static int snd_timer_user_release(struct inode *inode, struct file *file)
1274{
1275 struct snd_timer_user *tu;
1276
1277 if (file->private_data) {
1278 tu = file->private_data;
1279 file->private_data = NULL;
1280 if (tu->timeri)
1281 snd_timer_close(tu->timeri);
1282 kfree(tu->queue);
1283 kfree(tu->tqueue);
1284 kfree(tu);
1285 }
1286 return 0;
1287}
1288
1289static void snd_timer_user_zero_id(struct snd_timer_id *id)
1290{
1291 id->dev_class = SNDRV_TIMER_CLASS_NONE;
1292 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1293 id->card = -1;
1294 id->device = -1;
1295 id->subdevice = -1;
1296}
1297
1298static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1299{
1300 id->dev_class = timer->tmr_class;
1301 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1302 id->card = timer->card ? timer->card->number : -1;
1303 id->device = timer->tmr_device;
1304 id->subdevice = timer->tmr_subdevice;
1305}
1306
1307static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1308{
1309 struct snd_timer_id id;
1310 struct snd_timer *timer;
1311 struct list_head *p;
1312
1313 if (copy_from_user(&id, _tid, sizeof(id)))
1314 return -EFAULT;
1315 mutex_lock(®ister_mutex);
1316 if (id.dev_class < 0) { /* first item */
1317 if (list_empty(&snd_timer_list))
1318 snd_timer_user_zero_id(&id);
1319 else {
1320 timer = list_entry(snd_timer_list.next,
1321 struct snd_timer, device_list);
1322 snd_timer_user_copy_id(&id, timer);
1323 }
1324 } else {
1325 switch (id.dev_class) {
1326 case SNDRV_TIMER_CLASS_GLOBAL:
1327 id.device = id.device < 0 ? 0 : id.device + 1;
1328 list_for_each(p, &snd_timer_list) {
1329 timer = list_entry(p, struct snd_timer, device_list);
1330 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1331 snd_timer_user_copy_id(&id, timer);
1332 break;
1333 }
1334 if (timer->tmr_device >= id.device) {
1335 snd_timer_user_copy_id(&id, timer);
1336 break;
1337 }
1338 }
1339 if (p == &snd_timer_list)
1340 snd_timer_user_zero_id(&id);
1341 break;
1342 case SNDRV_TIMER_CLASS_CARD:
1343 case SNDRV_TIMER_CLASS_PCM:
1344 if (id.card < 0) {
1345 id.card = 0;
1346 } else {
1347 if (id.card < 0) {
1348 id.card = 0;
1349 } else {
1350 if (id.device < 0) {
1351 id.device = 0;
1352 } else {
1353 if (id.subdevice < 0) {
1354 id.subdevice = 0;
1355 } else {
1356 id.subdevice++;
1357 }
1358 }
1359 }
1360 }
1361 list_for_each(p, &snd_timer_list) {
1362 timer = list_entry(p, struct snd_timer, device_list);
1363 if (timer->tmr_class > id.dev_class) {
1364 snd_timer_user_copy_id(&id, timer);
1365 break;
1366 }
1367 if (timer->tmr_class < id.dev_class)
1368 continue;
1369 if (timer->card->number > id.card) {
1370 snd_timer_user_copy_id(&id, timer);
1371 break;
1372 }
1373 if (timer->card->number < id.card)
1374 continue;
1375 if (timer->tmr_device > id.device) {
1376 snd_timer_user_copy_id(&id, timer);
1377 break;
1378 }
1379 if (timer->tmr_device < id.device)
1380 continue;
1381 if (timer->tmr_subdevice > id.subdevice) {
1382 snd_timer_user_copy_id(&id, timer);
1383 break;
1384 }
1385 if (timer->tmr_subdevice < id.subdevice)
1386 continue;
1387 snd_timer_user_copy_id(&id, timer);
1388 break;
1389 }
1390 if (p == &snd_timer_list)
1391 snd_timer_user_zero_id(&id);
1392 break;
1393 default:
1394 snd_timer_user_zero_id(&id);
1395 }
1396 }
1397 mutex_unlock(®ister_mutex);
1398 if (copy_to_user(_tid, &id, sizeof(*_tid)))
1399 return -EFAULT;
1400 return 0;
1401}
1402
1403static int snd_timer_user_ginfo(struct file *file,
1404 struct snd_timer_ginfo __user *_ginfo)
1405{
1406 struct snd_timer_ginfo *ginfo;
1407 struct snd_timer_id tid;
1408 struct snd_timer *t;
1409 struct list_head *p;
1410 int err = 0;
1411
1412 ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1413 if (IS_ERR(ginfo))
1414 return PTR_ERR(ginfo);
1415
1416 tid = ginfo->tid;
1417 memset(ginfo, 0, sizeof(*ginfo));
1418 ginfo->tid = tid;
1419 mutex_lock(®ister_mutex);
1420 t = snd_timer_find(&tid);
1421 if (t != NULL) {
1422 ginfo->card = t->card ? t->card->number : -1;
1423 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1424 ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1425 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1426 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1427 ginfo->resolution = t->hw.resolution;
1428 if (t->hw.resolution_min > 0) {
1429 ginfo->resolution_min = t->hw.resolution_min;
1430 ginfo->resolution_max = t->hw.resolution_max;
1431 }
1432 list_for_each(p, &t->open_list_head) {
1433 ginfo->clients++;
1434 }
1435 } else {
1436 err = -ENODEV;
1437 }
1438 mutex_unlock(®ister_mutex);
1439 if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1440 err = -EFAULT;
1441 kfree(ginfo);
1442 return err;
1443}
1444
1445static int snd_timer_user_gparams(struct file *file,
1446 struct snd_timer_gparams __user *_gparams)
1447{
1448 struct snd_timer_gparams gparams;
1449 struct snd_timer *t;
1450 int err;
1451
1452 if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1453 return -EFAULT;
1454 mutex_lock(®ister_mutex);
1455 t = snd_timer_find(&gparams.tid);
1456 if (!t) {
1457 err = -ENODEV;
1458 goto _error;
1459 }
1460 if (!list_empty(&t->open_list_head)) {
1461 err = -EBUSY;
1462 goto _error;
1463 }
1464 if (!t->hw.set_period) {
1465 err = -ENOSYS;
1466 goto _error;
1467 }
1468 err = t->hw.set_period(t, gparams.period_num, gparams.period_den);
1469_error:
1470 mutex_unlock(®ister_mutex);
1471 return err;
1472}
1473
1474static int snd_timer_user_gstatus(struct file *file,
1475 struct snd_timer_gstatus __user *_gstatus)
1476{
1477 struct snd_timer_gstatus gstatus;
1478 struct snd_timer_id tid;
1479 struct snd_timer *t;
1480 int err = 0;
1481
1482 if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1483 return -EFAULT;
1484 tid = gstatus.tid;
1485 memset(&gstatus, 0, sizeof(gstatus));
1486 gstatus.tid = tid;
1487 mutex_lock(®ister_mutex);
1488 t = snd_timer_find(&tid);
1489 if (t != NULL) {
1490 if (t->hw.c_resolution)
1491 gstatus.resolution = t->hw.c_resolution(t);
1492 else
1493 gstatus.resolution = t->hw.resolution;
1494 if (t->hw.precise_resolution) {
1495 t->hw.precise_resolution(t, &gstatus.resolution_num,
1496 &gstatus.resolution_den);
1497 } else {
1498 gstatus.resolution_num = gstatus.resolution;
1499 gstatus.resolution_den = 1000000000uL;
1500 }
1501 } else {
1502 err = -ENODEV;
1503 }
1504 mutex_unlock(®ister_mutex);
1505 if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1506 err = -EFAULT;
1507 return err;
1508}
1509
1510static int snd_timer_user_tselect(struct file *file,
1511 struct snd_timer_select __user *_tselect)
1512{
1513 struct snd_timer_user *tu;
1514 struct snd_timer_select tselect;
1515 char str[32];
1516 int err = 0;
1517
1518 tu = file->private_data;
1519 mutex_lock(&tu->tread_sem);
1520 if (tu->timeri) {
1521 snd_timer_close(tu->timeri);
1522 tu->timeri = NULL;
1523 }
1524 if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1525 err = -EFAULT;
1526 goto __err;
1527 }
1528 sprintf(str, "application %i", current->pid);
1529 if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1530 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1531 err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1532 if (err < 0)
1533 goto __err;
1534
1535 kfree(tu->queue);
1536 tu->queue = NULL;
1537 kfree(tu->tqueue);
1538 tu->tqueue = NULL;
1539 if (tu->tread) {
1540 tu->tqueue = kmalloc(tu->queue_size * sizeof(struct snd_timer_tread),
1541 GFP_KERNEL);
1542 if (tu->tqueue == NULL)
1543 err = -ENOMEM;
1544 } else {
1545 tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1546 GFP_KERNEL);
1547 if (tu->queue == NULL)
1548 err = -ENOMEM;
1549 }
1550
1551 if (err < 0) {
1552 snd_timer_close(tu->timeri);
1553 tu->timeri = NULL;
1554 } else {
1555 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1556 tu->timeri->callback = tu->tread
1557 ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1558 tu->timeri->ccallback = snd_timer_user_ccallback;
1559 tu->timeri->callback_data = (void *)tu;
1560 }
1561
1562 __err:
1563 mutex_unlock(&tu->tread_sem);
1564 return err;
1565}
1566
1567static int snd_timer_user_info(struct file *file,
1568 struct snd_timer_info __user *_info)
1569{
1570 struct snd_timer_user *tu;
1571 struct snd_timer_info *info;
1572 struct snd_timer *t;
1573 int err = 0;
1574
1575 tu = file->private_data;
1576 if (!tu->timeri)
1577 return -EBADFD;
1578 t = tu->timeri->timer;
1579 if (!t)
1580 return -EBADFD;
1581
1582 info = kzalloc(sizeof(*info), GFP_KERNEL);
1583 if (! info)
1584 return -ENOMEM;
1585 info->card = t->card ? t->card->number : -1;
1586 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1587 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1588 strlcpy(info->id, t->id, sizeof(info->id));
1589 strlcpy(info->name, t->name, sizeof(info->name));
1590 info->resolution = t->hw.resolution;
1591 if (copy_to_user(_info, info, sizeof(*_info)))
1592 err = -EFAULT;
1593 kfree(info);
1594 return err;
1595}
1596
1597static int snd_timer_user_params(struct file *file,
1598 struct snd_timer_params __user *_params)
1599{
1600 struct snd_timer_user *tu;
1601 struct snd_timer_params params;
1602 struct snd_timer *t;
1603 struct snd_timer_read *tr;
1604 struct snd_timer_tread *ttr;
1605 int err;
1606
1607 tu = file->private_data;
1608 if (!tu->timeri)
1609 return -EBADFD;
1610 t = tu->timeri->timer;
1611 if (!t)
1612 return -EBADFD;
1613 if (copy_from_user(¶ms, _params, sizeof(params)))
1614 return -EFAULT;
1615 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE) && params.ticks < 1) {
1616 err = -EINVAL;
1617 goto _end;
1618 }
1619 if (params.queue_size > 0 &&
1620 (params.queue_size < 32 || params.queue_size > 1024)) {
1621 err = -EINVAL;
1622 goto _end;
1623 }
1624 if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1625 (1<<SNDRV_TIMER_EVENT_TICK)|
1626 (1<<SNDRV_TIMER_EVENT_START)|
1627 (1<<SNDRV_TIMER_EVENT_STOP)|
1628 (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1629 (1<<SNDRV_TIMER_EVENT_PAUSE)|
1630 (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1631 (1<<SNDRV_TIMER_EVENT_RESUME)|
1632 (1<<SNDRV_TIMER_EVENT_MSTART)|
1633 (1<<SNDRV_TIMER_EVENT_MSTOP)|
1634 (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1635 (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1636 (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1637 (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1638 err = -EINVAL;
1639 goto _end;
1640 }
1641 snd_timer_stop(tu->timeri);
1642 spin_lock_irq(&t->lock);
1643 tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1644 SNDRV_TIMER_IFLG_EXCLUSIVE|
1645 SNDRV_TIMER_IFLG_EARLY_EVENT);
1646 if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1647 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1648 if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1649 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1650 if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1651 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1652 spin_unlock_irq(&t->lock);
1653 if (params.queue_size > 0 &&
1654 (unsigned int)tu->queue_size != params.queue_size) {
1655 if (tu->tread) {
1656 ttr = kmalloc(params.queue_size * sizeof(*ttr),
1657 GFP_KERNEL);
1658 if (ttr) {
1659 kfree(tu->tqueue);
1660 tu->queue_size = params.queue_size;
1661 tu->tqueue = ttr;
1662 }
1663 } else {
1664 tr = kmalloc(params.queue_size * sizeof(*tr),
1665 GFP_KERNEL);
1666 if (tr) {
1667 kfree(tu->queue);
1668 tu->queue_size = params.queue_size;
1669 tu->queue = tr;
1670 }
1671 }
1672 }
1673 tu->qhead = tu->qtail = tu->qused = 0;
1674 if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1675 if (tu->tread) {
1676 struct snd_timer_tread tread;
1677 tread.event = SNDRV_TIMER_EVENT_EARLY;
1678 tread.tstamp.tv_sec = 0;
1679 tread.tstamp.tv_nsec = 0;
1680 tread.val = 0;
1681 snd_timer_user_append_to_tqueue(tu, &tread);
1682 } else {
1683 struct snd_timer_read *r = &tu->queue[0];
1684 r->resolution = 0;
1685 r->ticks = 0;
1686 tu->qused++;
1687 tu->qtail++;
1688 }
1689 }
1690 tu->filter = params.filter;
1691 tu->ticks = params.ticks;
1692 err = 0;
1693 _end:
1694 if (copy_to_user(_params, ¶ms, sizeof(params)))
1695 return -EFAULT;
1696 return err;
1697}
1698
1699static int snd_timer_user_status(struct file *file,
1700 struct snd_timer_status __user *_status)
1701{
1702 struct snd_timer_user *tu;
1703 struct snd_timer_status status;
1704
1705 tu = file->private_data;
1706 if (!tu->timeri)
1707 return -EBADFD;
1708 memset(&status, 0, sizeof(status));
1709 status.tstamp = tu->tstamp;
1710 status.resolution = snd_timer_resolution(tu->timeri);
1711 status.lost = tu->timeri->lost;
1712 status.overrun = tu->overrun;
1713 spin_lock_irq(&tu->qlock);
1714 status.queue = tu->qused;
1715 spin_unlock_irq(&tu->qlock);
1716 if (copy_to_user(_status, &status, sizeof(status)))
1717 return -EFAULT;
1718 return 0;
1719}
1720
1721static int snd_timer_user_start(struct file *file)
1722{
1723 int err;
1724 struct snd_timer_user *tu;
1725
1726 tu = file->private_data;
1727 if (!tu->timeri)
1728 return -EBADFD;
1729 snd_timer_stop(tu->timeri);
1730 tu->timeri->lost = 0;
1731 tu->last_resolution = 0;
1732 return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1733}
1734
1735static int snd_timer_user_stop(struct file *file)
1736{
1737 int err;
1738 struct snd_timer_user *tu;
1739
1740 tu = file->private_data;
1741 if (!tu->timeri)
1742 return -EBADFD;
1743 return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1744}
1745
1746static int snd_timer_user_continue(struct file *file)
1747{
1748 int err;
1749 struct snd_timer_user *tu;
1750
1751 tu = file->private_data;
1752 if (!tu->timeri)
1753 return -EBADFD;
1754 tu->timeri->lost = 0;
1755 return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1756}
1757
1758static int snd_timer_user_pause(struct file *file)
1759{
1760 int err;
1761 struct snd_timer_user *tu;
1762
1763 tu = file->private_data;
1764 if (!tu->timeri)
1765 return -EBADFD;
1766 return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1767}
1768
1769enum {
1770 SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1771 SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1772 SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1773 SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1774};
1775
1776static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1777 unsigned long arg)
1778{
1779 struct snd_timer_user *tu;
1780 void __user *argp = (void __user *)arg;
1781 int __user *p = argp;
1782
1783 tu = file->private_data;
1784 switch (cmd) {
1785 case SNDRV_TIMER_IOCTL_PVERSION:
1786 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1787 case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1788 return snd_timer_user_next_device(argp);
1789 case SNDRV_TIMER_IOCTL_TREAD:
1790 {
1791 int xarg;
1792
1793 mutex_lock(&tu->tread_sem);
1794 if (tu->timeri) { /* too late */
1795 mutex_unlock(&tu->tread_sem);
1796 return -EBUSY;
1797 }
1798 if (get_user(xarg, p)) {
1799 mutex_unlock(&tu->tread_sem);
1800 return -EFAULT;
1801 }
1802 tu->tread = xarg ? 1 : 0;
1803 mutex_unlock(&tu->tread_sem);
1804 return 0;
1805 }
1806 case SNDRV_TIMER_IOCTL_GINFO:
1807 return snd_timer_user_ginfo(file, argp);
1808 case SNDRV_TIMER_IOCTL_GPARAMS:
1809 return snd_timer_user_gparams(file, argp);
1810 case SNDRV_TIMER_IOCTL_GSTATUS:
1811 return snd_timer_user_gstatus(file, argp);
1812 case SNDRV_TIMER_IOCTL_SELECT:
1813 return snd_timer_user_tselect(file, argp);
1814 case SNDRV_TIMER_IOCTL_INFO:
1815 return snd_timer_user_info(file, argp);
1816 case SNDRV_TIMER_IOCTL_PARAMS:
1817 return snd_timer_user_params(file, argp);
1818 case SNDRV_TIMER_IOCTL_STATUS:
1819 return snd_timer_user_status(file, argp);
1820 case SNDRV_TIMER_IOCTL_START:
1821 case SNDRV_TIMER_IOCTL_START_OLD:
1822 return snd_timer_user_start(file);
1823 case SNDRV_TIMER_IOCTL_STOP:
1824 case SNDRV_TIMER_IOCTL_STOP_OLD:
1825 return snd_timer_user_stop(file);
1826 case SNDRV_TIMER_IOCTL_CONTINUE:
1827 case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1828 return snd_timer_user_continue(file);
1829 case SNDRV_TIMER_IOCTL_PAUSE:
1830 case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1831 return snd_timer_user_pause(file);
1832 }
1833 return -ENOTTY;
1834}
1835
1836static int snd_timer_user_fasync(int fd, struct file * file, int on)
1837{
1838 struct snd_timer_user *tu;
1839
1840 tu = file->private_data;
1841 return fasync_helper(fd, file, on, &tu->fasync);
1842}
1843
1844static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
1845 size_t count, loff_t *offset)
1846{
1847 struct snd_timer_user *tu;
1848 long result = 0, unit;
1849 int err = 0;
1850
1851 tu = file->private_data;
1852 unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
1853 spin_lock_irq(&tu->qlock);
1854 while ((long)count - result >= unit) {
1855 while (!tu->qused) {
1856 wait_queue_t wait;
1857
1858 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1859 err = -EAGAIN;
1860 break;
1861 }
1862
1863 set_current_state(TASK_INTERRUPTIBLE);
1864 init_waitqueue_entry(&wait, current);
1865 add_wait_queue(&tu->qchange_sleep, &wait);
1866
1867 spin_unlock_irq(&tu->qlock);
1868 schedule();
1869 spin_lock_irq(&tu->qlock);
1870
1871 remove_wait_queue(&tu->qchange_sleep, &wait);
1872
1873 if (signal_pending(current)) {
1874 err = -ERESTARTSYS;
1875 break;
1876 }
1877 }
1878
1879 spin_unlock_irq(&tu->qlock);
1880 if (err < 0)
1881 goto _error;
1882
1883 if (tu->tread) {
1884 if (copy_to_user(buffer, &tu->tqueue[tu->qhead++],
1885 sizeof(struct snd_timer_tread))) {
1886 err = -EFAULT;
1887 goto _error;
1888 }
1889 } else {
1890 if (copy_to_user(buffer, &tu->queue[tu->qhead++],
1891 sizeof(struct snd_timer_read))) {
1892 err = -EFAULT;
1893 goto _error;
1894 }
1895 }
1896
1897 tu->qhead %= tu->queue_size;
1898
1899 result += unit;
1900 buffer += unit;
1901
1902 spin_lock_irq(&tu->qlock);
1903 tu->qused--;
1904 }
1905 spin_unlock_irq(&tu->qlock);
1906 _error:
1907 return result > 0 ? result : err;
1908}
1909
1910static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
1911{
1912 unsigned int mask;
1913 struct snd_timer_user *tu;
1914
1915 tu = file->private_data;
1916
1917 poll_wait(file, &tu->qchange_sleep, wait);
1918
1919 mask = 0;
1920 if (tu->qused)
1921 mask |= POLLIN | POLLRDNORM;
1922
1923 return mask;
1924}
1925
1926#ifdef CONFIG_COMPAT
1927#include "timer_compat.c"
1928#else
1929#define snd_timer_user_ioctl_compat NULL
1930#endif
1931
1932static const struct file_operations snd_timer_f_ops =
1933{
1934 .owner = THIS_MODULE,
1935 .read = snd_timer_user_read,
1936 .open = snd_timer_user_open,
1937 .release = snd_timer_user_release,
1938 .llseek = no_llseek,
1939 .poll = snd_timer_user_poll,
1940 .unlocked_ioctl = snd_timer_user_ioctl,
1941 .compat_ioctl = snd_timer_user_ioctl_compat,
1942 .fasync = snd_timer_user_fasync,
1943};
1944
1945/*
1946 * ENTRY functions
1947 */
1948
1949static int __init alsa_timer_init(void)
1950{
1951 int err;
1952
1953#ifdef SNDRV_OSS_INFO_DEV_TIMERS
1954 snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
1955 "system timer");
1956#endif
1957
1958 if ((err = snd_timer_register_system()) < 0)
1959 pr_err("ALSA: unable to register system timer (%i)\n", err);
1960 if ((err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
1961 &snd_timer_f_ops, NULL, "timer")) < 0)
1962 pr_err("ALSA: unable to register timer device (%i)\n", err);
1963 snd_timer_proc_init();
1964 return 0;
1965}
1966
1967static void __exit alsa_timer_exit(void)
1968{
1969 struct list_head *p, *n;
1970
1971 snd_unregister_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0);
1972 /* unregister the system timer */
1973 list_for_each_safe(p, n, &snd_timer_list) {
1974 struct snd_timer *timer = list_entry(p, struct snd_timer, device_list);
1975 snd_timer_free(timer);
1976 }
1977 snd_timer_proc_done();
1978#ifdef SNDRV_OSS_INFO_DEV_TIMERS
1979 snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
1980#endif
1981}
1982
1983module_init(alsa_timer_init)
1984module_exit(alsa_timer_exit)
1985
1986EXPORT_SYMBOL(snd_timer_open);
1987EXPORT_SYMBOL(snd_timer_close);
1988EXPORT_SYMBOL(snd_timer_resolution);
1989EXPORT_SYMBOL(snd_timer_start);
1990EXPORT_SYMBOL(snd_timer_stop);
1991EXPORT_SYMBOL(snd_timer_continue);
1992EXPORT_SYMBOL(snd_timer_pause);
1993EXPORT_SYMBOL(snd_timer_new);
1994EXPORT_SYMBOL(snd_timer_notify);
1995EXPORT_SYMBOL(snd_timer_global_new);
1996EXPORT_SYMBOL(snd_timer_global_free);
1997EXPORT_SYMBOL(snd_timer_global_register);
1998EXPORT_SYMBOL(snd_timer_interrupt);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Timers abstract layer
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/delay.h>
8#include <linux/init.h>
9#include <linux/slab.h>
10#include <linux/time.h>
11#include <linux/mutex.h>
12#include <linux/device.h>
13#include <linux/module.h>
14#include <linux/string.h>
15#include <linux/sched/signal.h>
16#include <linux/anon_inodes.h>
17#include <linux/idr.h>
18#include <sound/core.h>
19#include <sound/timer.h>
20#include <sound/control.h>
21#include <sound/info.h>
22#include <sound/minors.h>
23#include <sound/initval.h>
24#include <linux/kmod.h>
25
26/* internal flags */
27#define SNDRV_TIMER_IFLG_PAUSED 0x00010000
28#define SNDRV_TIMER_IFLG_DEAD 0x00020000
29
30#if IS_ENABLED(CONFIG_SND_HRTIMER)
31#define DEFAULT_TIMER_LIMIT 4
32#else
33#define DEFAULT_TIMER_LIMIT 1
34#endif
35
36static int timer_limit = DEFAULT_TIMER_LIMIT;
37static int timer_tstamp_monotonic = 1;
38MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>");
39MODULE_DESCRIPTION("ALSA timer interface");
40MODULE_LICENSE("GPL");
41module_param(timer_limit, int, 0444);
42MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
43module_param(timer_tstamp_monotonic, int, 0444);
44MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
45
46MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
47MODULE_ALIAS("devname:snd/timer");
48
49enum timer_tread_format {
50 TREAD_FORMAT_NONE = 0,
51 TREAD_FORMAT_TIME64,
52 TREAD_FORMAT_TIME32,
53};
54
55struct snd_timer_tread32 {
56 int event;
57 s32 tstamp_sec;
58 s32 tstamp_nsec;
59 unsigned int val;
60};
61
62struct snd_timer_tread64 {
63 int event;
64 u8 pad1[4];
65 s64 tstamp_sec;
66 s64 tstamp_nsec;
67 unsigned int val;
68 u8 pad2[4];
69};
70
71struct snd_timer_user {
72 struct snd_timer_instance *timeri;
73 int tread; /* enhanced read with timestamps and events */
74 unsigned long ticks;
75 unsigned long overrun;
76 int qhead;
77 int qtail;
78 int qused;
79 int queue_size;
80 bool disconnected;
81 struct snd_timer_read *queue;
82 struct snd_timer_tread64 *tqueue;
83 spinlock_t qlock;
84 unsigned long last_resolution;
85 unsigned int filter;
86 struct timespec64 tstamp; /* trigger tstamp */
87 wait_queue_head_t qchange_sleep;
88 struct snd_fasync *fasync;
89 struct mutex ioctl_lock;
90};
91
92struct snd_timer_status32 {
93 s32 tstamp_sec; /* Timestamp - last update */
94 s32 tstamp_nsec;
95 unsigned int resolution; /* current period resolution in ns */
96 unsigned int lost; /* counter of master tick lost */
97 unsigned int overrun; /* count of read queue overruns */
98 unsigned int queue; /* used queue size */
99 unsigned char reserved[64]; /* reserved */
100};
101
102#define SNDRV_TIMER_IOCTL_STATUS32 _IOR('T', 0x14, struct snd_timer_status32)
103
104struct snd_timer_status64 {
105 s64 tstamp_sec; /* Timestamp - last update */
106 s64 tstamp_nsec;
107 unsigned int resolution; /* current period resolution in ns */
108 unsigned int lost; /* counter of master tick lost */
109 unsigned int overrun; /* count of read queue overruns */
110 unsigned int queue; /* used queue size */
111 unsigned char reserved[64]; /* reserved */
112};
113
114#ifdef CONFIG_SND_UTIMER
115#define SNDRV_UTIMERS_MAX_COUNT 128
116/* Internal data structure for keeping the state of the userspace-driven timer */
117struct snd_utimer {
118 char *name;
119 struct snd_timer *timer;
120 unsigned int id;
121};
122#endif
123
124#define SNDRV_TIMER_IOCTL_STATUS64 _IOR('T', 0x14, struct snd_timer_status64)
125
126/* list of timers */
127static LIST_HEAD(snd_timer_list);
128
129/* list of slave instances */
130static LIST_HEAD(snd_timer_slave_list);
131
132/* lock for slave active lists */
133static DEFINE_SPINLOCK(slave_active_lock);
134
135#define MAX_SLAVE_INSTANCES 1000
136static int num_slaves;
137
138static DEFINE_MUTEX(register_mutex);
139
140static int snd_timer_free(struct snd_timer *timer);
141static int snd_timer_dev_free(struct snd_device *device);
142static int snd_timer_dev_register(struct snd_device *device);
143static int snd_timer_dev_disconnect(struct snd_device *device);
144
145static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
146
147/*
148 * create a timer instance with the given owner string.
149 */
150struct snd_timer_instance *snd_timer_instance_new(const char *owner)
151{
152 struct snd_timer_instance *timeri;
153
154 timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
155 if (timeri == NULL)
156 return NULL;
157 timeri->owner = kstrdup(owner, GFP_KERNEL);
158 if (! timeri->owner) {
159 kfree(timeri);
160 return NULL;
161 }
162 INIT_LIST_HEAD(&timeri->open_list);
163 INIT_LIST_HEAD(&timeri->active_list);
164 INIT_LIST_HEAD(&timeri->ack_list);
165 INIT_LIST_HEAD(&timeri->slave_list_head);
166 INIT_LIST_HEAD(&timeri->slave_active_head);
167
168 return timeri;
169}
170EXPORT_SYMBOL(snd_timer_instance_new);
171
172void snd_timer_instance_free(struct snd_timer_instance *timeri)
173{
174 if (timeri) {
175 if (timeri->private_free)
176 timeri->private_free(timeri);
177 kfree(timeri->owner);
178 kfree(timeri);
179 }
180}
181EXPORT_SYMBOL(snd_timer_instance_free);
182
183/*
184 * find a timer instance from the given timer id
185 */
186static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
187{
188 struct snd_timer *timer;
189
190 list_for_each_entry(timer, &snd_timer_list, device_list) {
191 if (timer->tmr_class != tid->dev_class)
192 continue;
193 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
194 timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
195 (timer->card == NULL ||
196 timer->card->number != tid->card))
197 continue;
198 if (timer->tmr_device != tid->device)
199 continue;
200 if (timer->tmr_subdevice != tid->subdevice)
201 continue;
202 return timer;
203 }
204 return NULL;
205}
206
207#ifdef CONFIG_MODULES
208
209static void snd_timer_request(struct snd_timer_id *tid)
210{
211 switch (tid->dev_class) {
212 case SNDRV_TIMER_CLASS_GLOBAL:
213 if (tid->device < timer_limit)
214 request_module("snd-timer-%i", tid->device);
215 break;
216 case SNDRV_TIMER_CLASS_CARD:
217 case SNDRV_TIMER_CLASS_PCM:
218 if (tid->card < snd_ecards_limit)
219 request_module("snd-card-%i", tid->card);
220 break;
221 default:
222 break;
223 }
224}
225
226#endif
227
228/* move the slave if it belongs to the master; return 1 if match */
229static int check_matching_master_slave(struct snd_timer_instance *master,
230 struct snd_timer_instance *slave)
231{
232 if (slave->slave_class != master->slave_class ||
233 slave->slave_id != master->slave_id)
234 return 0;
235 if (master->timer->num_instances >= master->timer->max_instances)
236 return -EBUSY;
237 list_move_tail(&slave->open_list, &master->slave_list_head);
238 master->timer->num_instances++;
239 guard(spinlock_irq)(&slave_active_lock);
240 guard(spinlock)(&master->timer->lock);
241 slave->master = master;
242 slave->timer = master->timer;
243 if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
244 list_add_tail(&slave->active_list, &master->slave_active_head);
245 return 1;
246}
247
248/*
249 * look for a master instance matching with the slave id of the given slave.
250 * when found, relink the open_link of the slave.
251 *
252 * call this with register_mutex down.
253 */
254static int snd_timer_check_slave(struct snd_timer_instance *slave)
255{
256 struct snd_timer *timer;
257 struct snd_timer_instance *master;
258 int err = 0;
259
260 /* FIXME: it's really dumb to look up all entries.. */
261 list_for_each_entry(timer, &snd_timer_list, device_list) {
262 list_for_each_entry(master, &timer->open_list_head, open_list) {
263 err = check_matching_master_slave(master, slave);
264 if (err != 0) /* match found or error */
265 goto out;
266 }
267 }
268 out:
269 return err < 0 ? err : 0;
270}
271
272/*
273 * look for slave instances matching with the slave id of the given master.
274 * when found, relink the open_link of slaves.
275 *
276 * call this with register_mutex down.
277 */
278static int snd_timer_check_master(struct snd_timer_instance *master)
279{
280 struct snd_timer_instance *slave, *tmp;
281 int err = 0;
282
283 /* check all pending slaves */
284 list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
285 err = check_matching_master_slave(master, slave);
286 if (err < 0)
287 break;
288 }
289 return err < 0 ? err : 0;
290}
291
292static void snd_timer_close_locked(struct snd_timer_instance *timeri,
293 struct device **card_devp_to_put);
294
295/*
296 * open a timer instance
297 * when opening a master, the slave id must be here given.
298 */
299int snd_timer_open(struct snd_timer_instance *timeri,
300 struct snd_timer_id *tid,
301 unsigned int slave_id)
302{
303 struct snd_timer *timer;
304 struct device *card_dev_to_put = NULL;
305 int err;
306
307 mutex_lock(®ister_mutex);
308 if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
309 /* open a slave instance */
310 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
311 tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
312 pr_debug("ALSA: timer: invalid slave class %i\n",
313 tid->dev_sclass);
314 err = -EINVAL;
315 goto unlock;
316 }
317 if (num_slaves >= MAX_SLAVE_INSTANCES) {
318 err = -EBUSY;
319 goto unlock;
320 }
321 timeri->slave_class = tid->dev_sclass;
322 timeri->slave_id = tid->device;
323 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
324 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
325 num_slaves++;
326 err = snd_timer_check_slave(timeri);
327 goto list_added;
328 }
329
330 /* open a master instance */
331 timer = snd_timer_find(tid);
332#ifdef CONFIG_MODULES
333 if (!timer) {
334 mutex_unlock(®ister_mutex);
335 snd_timer_request(tid);
336 mutex_lock(®ister_mutex);
337 timer = snd_timer_find(tid);
338 }
339#endif
340 if (!timer) {
341 err = -ENODEV;
342 goto unlock;
343 }
344 if (!list_empty(&timer->open_list_head)) {
345 struct snd_timer_instance *t =
346 list_entry(timer->open_list_head.next,
347 struct snd_timer_instance, open_list);
348 if (t->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
349 err = -EBUSY;
350 goto unlock;
351 }
352 }
353 if (timer->num_instances >= timer->max_instances) {
354 err = -EBUSY;
355 goto unlock;
356 }
357 if (!try_module_get(timer->module)) {
358 err = -EBUSY;
359 goto unlock;
360 }
361 /* take a card refcount for safe disconnection */
362 if (timer->card) {
363 get_device(&timer->card->card_dev);
364 card_dev_to_put = &timer->card->card_dev;
365 }
366
367 if (list_empty(&timer->open_list_head) && timer->hw.open) {
368 err = timer->hw.open(timer);
369 if (err) {
370 module_put(timer->module);
371 goto unlock;
372 }
373 }
374
375 timeri->timer = timer;
376 timeri->slave_class = tid->dev_sclass;
377 timeri->slave_id = slave_id;
378
379 list_add_tail(&timeri->open_list, &timer->open_list_head);
380 timer->num_instances++;
381 err = snd_timer_check_master(timeri);
382list_added:
383 if (err < 0)
384 snd_timer_close_locked(timeri, &card_dev_to_put);
385
386 unlock:
387 mutex_unlock(®ister_mutex);
388 /* put_device() is called after unlock for avoiding deadlock */
389 if (err < 0 && card_dev_to_put)
390 put_device(card_dev_to_put);
391 return err;
392}
393EXPORT_SYMBOL(snd_timer_open);
394
395/* remove slave links, called from snd_timer_close_locked() below */
396static void remove_slave_links(struct snd_timer_instance *timeri,
397 struct snd_timer *timer)
398{
399 struct snd_timer_instance *slave, *tmp;
400
401 guard(spinlock_irq)(&slave_active_lock);
402 guard(spinlock)(&timer->lock);
403 timeri->timer = NULL;
404 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head, open_list) {
405 list_move_tail(&slave->open_list, &snd_timer_slave_list);
406 timer->num_instances--;
407 slave->master = NULL;
408 slave->timer = NULL;
409 list_del_init(&slave->ack_list);
410 list_del_init(&slave->active_list);
411 }
412}
413
414/*
415 * close a timer instance
416 * call this with register_mutex down.
417 */
418static void snd_timer_close_locked(struct snd_timer_instance *timeri,
419 struct device **card_devp_to_put)
420{
421 struct snd_timer *timer = timeri->timer;
422
423 if (timer) {
424 guard(spinlock_irq)(&timer->lock);
425 timeri->flags |= SNDRV_TIMER_IFLG_DEAD;
426 }
427
428 if (!list_empty(&timeri->open_list)) {
429 list_del_init(&timeri->open_list);
430 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
431 num_slaves--;
432 }
433
434 /* force to stop the timer */
435 snd_timer_stop(timeri);
436
437 if (timer) {
438 timer->num_instances--;
439 /* wait, until the active callback is finished */
440 spin_lock_irq(&timer->lock);
441 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
442 spin_unlock_irq(&timer->lock);
443 udelay(10);
444 spin_lock_irq(&timer->lock);
445 }
446 spin_unlock_irq(&timer->lock);
447
448 remove_slave_links(timeri, timer);
449
450 /* slave doesn't need to release timer resources below */
451 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
452 timer = NULL;
453 }
454
455 if (timer) {
456 if (list_empty(&timer->open_list_head) && timer->hw.close)
457 timer->hw.close(timer);
458 /* release a card refcount for safe disconnection */
459 if (timer->card)
460 *card_devp_to_put = &timer->card->card_dev;
461 module_put(timer->module);
462 }
463}
464
465/*
466 * close a timer instance
467 */
468void snd_timer_close(struct snd_timer_instance *timeri)
469{
470 struct device *card_dev_to_put = NULL;
471
472 if (snd_BUG_ON(!timeri))
473 return;
474
475 scoped_guard(mutex, ®ister_mutex)
476 snd_timer_close_locked(timeri, &card_dev_to_put);
477 /* put_device() is called after unlock for avoiding deadlock */
478 if (card_dev_to_put)
479 put_device(card_dev_to_put);
480}
481EXPORT_SYMBOL(snd_timer_close);
482
483static unsigned long snd_timer_hw_resolution(struct snd_timer *timer)
484{
485 if (timer->hw.c_resolution)
486 return timer->hw.c_resolution(timer);
487 else
488 return timer->hw.resolution;
489}
490
491unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
492{
493 struct snd_timer * timer;
494 unsigned long ret = 0;
495
496 if (timeri == NULL)
497 return 0;
498 timer = timeri->timer;
499 if (timer) {
500 guard(spinlock_irqsave)(&timer->lock);
501 ret = snd_timer_hw_resolution(timer);
502 }
503 return ret;
504}
505EXPORT_SYMBOL(snd_timer_resolution);
506
507static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
508{
509 struct snd_timer *timer = ti->timer;
510 unsigned long resolution = 0;
511 struct snd_timer_instance *ts;
512 struct timespec64 tstamp;
513
514 if (timer_tstamp_monotonic)
515 ktime_get_ts64(&tstamp);
516 else
517 ktime_get_real_ts64(&tstamp);
518 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
519 event > SNDRV_TIMER_EVENT_PAUSE))
520 return;
521 if (timer &&
522 (event == SNDRV_TIMER_EVENT_START ||
523 event == SNDRV_TIMER_EVENT_CONTINUE))
524 resolution = snd_timer_hw_resolution(timer);
525 if (ti->ccallback)
526 ti->ccallback(ti, event, &tstamp, resolution);
527 if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
528 return;
529 if (timer == NULL)
530 return;
531 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
532 return;
533 event += 10; /* convert to SNDRV_TIMER_EVENT_MXXX */
534 list_for_each_entry(ts, &ti->slave_active_head, active_list)
535 if (ts->ccallback)
536 ts->ccallback(ts, event, &tstamp, resolution);
537}
538
539/* start/continue a master timer */
540static int snd_timer_start1(struct snd_timer_instance *timeri,
541 bool start, unsigned long ticks)
542{
543 struct snd_timer *timer;
544 int result;
545
546 timer = timeri->timer;
547 if (!timer)
548 return -EINVAL;
549
550 guard(spinlock_irqsave)(&timer->lock);
551 if (timeri->flags & SNDRV_TIMER_IFLG_DEAD)
552 return -EINVAL;
553 if (timer->card && timer->card->shutdown)
554 return -ENODEV;
555 if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
556 SNDRV_TIMER_IFLG_START))
557 return -EBUSY;
558
559 /* check the actual time for the start tick;
560 * bail out as error if it's way too low (< 100us)
561 */
562 if (start && !(timer->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
563 if ((u64)snd_timer_hw_resolution(timer) * ticks < 100000)
564 return -EINVAL;
565 }
566
567 if (start)
568 timeri->ticks = timeri->cticks = ticks;
569 else if (!timeri->cticks)
570 timeri->cticks = 1;
571 timeri->pticks = 0;
572
573 list_move_tail(&timeri->active_list, &timer->active_list_head);
574 if (timer->running) {
575 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
576 goto __start_now;
577 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
578 timeri->flags |= SNDRV_TIMER_IFLG_START;
579 result = 1; /* delayed start */
580 } else {
581 if (start)
582 timer->sticks = ticks;
583 timer->hw.start(timer);
584 __start_now:
585 timer->running++;
586 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
587 result = 0;
588 }
589 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
590 SNDRV_TIMER_EVENT_CONTINUE);
591 return result;
592}
593
594/* start/continue a slave timer */
595static int snd_timer_start_slave(struct snd_timer_instance *timeri,
596 bool start)
597{
598 guard(spinlock_irqsave)(&slave_active_lock);
599 if (timeri->flags & SNDRV_TIMER_IFLG_DEAD)
600 return -EINVAL;
601 if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING)
602 return -EBUSY;
603 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
604 if (timeri->master && timeri->timer) {
605 guard(spinlock)(&timeri->timer->lock);
606 list_add_tail(&timeri->active_list,
607 &timeri->master->slave_active_head);
608 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
609 SNDRV_TIMER_EVENT_CONTINUE);
610 }
611 return 1; /* delayed start */
612}
613
614/* stop/pause a master timer */
615static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
616{
617 struct snd_timer *timer;
618
619 timer = timeri->timer;
620 if (!timer)
621 return -EINVAL;
622 guard(spinlock_irqsave)(&timer->lock);
623 list_del_init(&timeri->ack_list);
624 list_del_init(&timeri->active_list);
625 if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
626 SNDRV_TIMER_IFLG_START)))
627 return -EBUSY;
628 if (timer->card && timer->card->shutdown)
629 return 0;
630 if (stop) {
631 timeri->cticks = timeri->ticks;
632 timeri->pticks = 0;
633 }
634 if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
635 !(--timer->running)) {
636 timer->hw.stop(timer);
637 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
638 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
639 snd_timer_reschedule(timer, 0);
640 if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
641 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
642 timer->hw.start(timer);
643 }
644 }
645 }
646 timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
647 if (stop)
648 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
649 else
650 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
651 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
652 SNDRV_TIMER_EVENT_PAUSE);
653 return 0;
654}
655
656/* stop/pause a slave timer */
657static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
658{
659 bool running;
660
661 guard(spinlock_irqsave)(&slave_active_lock);
662 running = timeri->flags & SNDRV_TIMER_IFLG_RUNNING;
663 timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
664 if (timeri->timer) {
665 guard(spinlock)(&timeri->timer->lock);
666 list_del_init(&timeri->ack_list);
667 list_del_init(&timeri->active_list);
668 if (running)
669 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
670 SNDRV_TIMER_EVENT_PAUSE);
671 }
672 return running ? 0 : -EBUSY;
673}
674
675/*
676 * start the timer instance
677 */
678int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
679{
680 if (timeri == NULL || ticks < 1)
681 return -EINVAL;
682 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
683 return snd_timer_start_slave(timeri, true);
684 else
685 return snd_timer_start1(timeri, true, ticks);
686}
687EXPORT_SYMBOL(snd_timer_start);
688
689/*
690 * stop the timer instance.
691 *
692 * do not call this from the timer callback!
693 */
694int snd_timer_stop(struct snd_timer_instance *timeri)
695{
696 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
697 return snd_timer_stop_slave(timeri, true);
698 else
699 return snd_timer_stop1(timeri, true);
700}
701EXPORT_SYMBOL(snd_timer_stop);
702
703/*
704 * start again.. the tick is kept.
705 */
706int snd_timer_continue(struct snd_timer_instance *timeri)
707{
708 /* timer can continue only after pause */
709 if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
710 return -EINVAL;
711
712 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
713 return snd_timer_start_slave(timeri, false);
714 else
715 return snd_timer_start1(timeri, false, 0);
716}
717EXPORT_SYMBOL(snd_timer_continue);
718
719/*
720 * pause.. remember the ticks left
721 */
722int snd_timer_pause(struct snd_timer_instance * timeri)
723{
724 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
725 return snd_timer_stop_slave(timeri, false);
726 else
727 return snd_timer_stop1(timeri, false);
728}
729EXPORT_SYMBOL(snd_timer_pause);
730
731/*
732 * reschedule the timer
733 *
734 * start pending instances and check the scheduling ticks.
735 * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
736 */
737static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
738{
739 struct snd_timer_instance *ti;
740 unsigned long ticks = ~0UL;
741
742 list_for_each_entry(ti, &timer->active_list_head, active_list) {
743 if (ti->flags & SNDRV_TIMER_IFLG_START) {
744 ti->flags &= ~SNDRV_TIMER_IFLG_START;
745 ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
746 timer->running++;
747 }
748 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
749 if (ticks > ti->cticks)
750 ticks = ti->cticks;
751 }
752 }
753 if (ticks == ~0UL) {
754 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
755 return;
756 }
757 if (ticks > timer->hw.ticks)
758 ticks = timer->hw.ticks;
759 if (ticks_left != ticks)
760 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
761 timer->sticks = ticks;
762}
763
764/* call callbacks in timer ack list */
765static void snd_timer_process_callbacks(struct snd_timer *timer,
766 struct list_head *head)
767{
768 struct snd_timer_instance *ti;
769 unsigned long resolution, ticks;
770
771 while (!list_empty(head)) {
772 ti = list_first_entry(head, struct snd_timer_instance,
773 ack_list);
774
775 /* remove from ack_list and make empty */
776 list_del_init(&ti->ack_list);
777
778 if (!(ti->flags & SNDRV_TIMER_IFLG_DEAD)) {
779 ticks = ti->pticks;
780 ti->pticks = 0;
781 resolution = ti->resolution;
782 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
783 spin_unlock(&timer->lock);
784 if (ti->callback)
785 ti->callback(ti, resolution, ticks);
786 spin_lock(&timer->lock);
787 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
788 }
789 }
790}
791
792/* clear pending instances from ack list */
793static void snd_timer_clear_callbacks(struct snd_timer *timer,
794 struct list_head *head)
795{
796 guard(spinlock_irqsave)(&timer->lock);
797 while (!list_empty(head))
798 list_del_init(head->next);
799}
800
801/*
802 * timer work
803 *
804 */
805static void snd_timer_work(struct work_struct *work)
806{
807 struct snd_timer *timer = container_of(work, struct snd_timer, task_work);
808
809 if (timer->card && timer->card->shutdown) {
810 snd_timer_clear_callbacks(timer, &timer->sack_list_head);
811 return;
812 }
813
814 guard(spinlock_irqsave)(&timer->lock);
815 snd_timer_process_callbacks(timer, &timer->sack_list_head);
816}
817
818/*
819 * timer interrupt
820 *
821 * ticks_left is usually equal to timer->sticks.
822 *
823 */
824void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
825{
826 struct snd_timer_instance *ti, *ts, *tmp;
827 unsigned long resolution;
828 struct list_head *ack_list_head;
829
830 if (timer == NULL)
831 return;
832
833 if (timer->card && timer->card->shutdown) {
834 snd_timer_clear_callbacks(timer, &timer->ack_list_head);
835 return;
836 }
837
838 guard(spinlock_irqsave)(&timer->lock);
839
840 /* remember the current resolution */
841 resolution = snd_timer_hw_resolution(timer);
842
843 /* loop for all active instances
844 * Here we cannot use list_for_each_entry because the active_list of a
845 * processed instance is relinked to done_list_head before the callback
846 * is called.
847 */
848 list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
849 active_list) {
850 if (ti->flags & SNDRV_TIMER_IFLG_DEAD)
851 continue;
852 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
853 continue;
854 ti->pticks += ticks_left;
855 ti->resolution = resolution;
856 if (ti->cticks < ticks_left)
857 ti->cticks = 0;
858 else
859 ti->cticks -= ticks_left;
860 if (ti->cticks) /* not expired */
861 continue;
862 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
863 ti->cticks = ti->ticks;
864 } else {
865 ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
866 --timer->running;
867 list_del_init(&ti->active_list);
868 }
869 if ((timer->hw.flags & SNDRV_TIMER_HW_WORK) ||
870 (ti->flags & SNDRV_TIMER_IFLG_FAST))
871 ack_list_head = &timer->ack_list_head;
872 else
873 ack_list_head = &timer->sack_list_head;
874 if (list_empty(&ti->ack_list))
875 list_add_tail(&ti->ack_list, ack_list_head);
876 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
877 ts->pticks = ti->pticks;
878 ts->resolution = resolution;
879 if (list_empty(&ts->ack_list))
880 list_add_tail(&ts->ack_list, ack_list_head);
881 }
882 }
883 if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
884 snd_timer_reschedule(timer, timer->sticks);
885 if (timer->running) {
886 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
887 timer->hw.stop(timer);
888 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
889 }
890 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
891 (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
892 /* restart timer */
893 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
894 timer->hw.start(timer);
895 }
896 } else {
897 timer->hw.stop(timer);
898 }
899
900 /* now process all fast callbacks */
901 snd_timer_process_callbacks(timer, &timer->ack_list_head);
902
903 /* do we have any slow callbacks? */
904 if (!list_empty(&timer->sack_list_head))
905 queue_work(system_highpri_wq, &timer->task_work);
906}
907EXPORT_SYMBOL(snd_timer_interrupt);
908
909/*
910
911 */
912
913int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
914 struct snd_timer **rtimer)
915{
916 struct snd_timer *timer;
917 int err;
918 static const struct snd_device_ops ops = {
919 .dev_free = snd_timer_dev_free,
920 .dev_register = snd_timer_dev_register,
921 .dev_disconnect = snd_timer_dev_disconnect,
922 };
923
924 if (snd_BUG_ON(!tid))
925 return -EINVAL;
926 if (tid->dev_class == SNDRV_TIMER_CLASS_CARD ||
927 tid->dev_class == SNDRV_TIMER_CLASS_PCM) {
928 if (WARN_ON(!card))
929 return -EINVAL;
930 }
931 if (rtimer)
932 *rtimer = NULL;
933 timer = kzalloc(sizeof(*timer), GFP_KERNEL);
934 if (!timer)
935 return -ENOMEM;
936 timer->tmr_class = tid->dev_class;
937 timer->card = card;
938 timer->tmr_device = tid->device;
939 timer->tmr_subdevice = tid->subdevice;
940 if (id)
941 strscpy(timer->id, id, sizeof(timer->id));
942 timer->sticks = 1;
943 INIT_LIST_HEAD(&timer->device_list);
944 INIT_LIST_HEAD(&timer->open_list_head);
945 INIT_LIST_HEAD(&timer->active_list_head);
946 INIT_LIST_HEAD(&timer->ack_list_head);
947 INIT_LIST_HEAD(&timer->sack_list_head);
948 spin_lock_init(&timer->lock);
949 INIT_WORK(&timer->task_work, snd_timer_work);
950 timer->max_instances = 1000; /* default limit per timer */
951 if (card != NULL) {
952 timer->module = card->module;
953 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
954 if (err < 0) {
955 snd_timer_free(timer);
956 return err;
957 }
958 }
959 if (rtimer)
960 *rtimer = timer;
961 return 0;
962}
963EXPORT_SYMBOL(snd_timer_new);
964
965static int snd_timer_free(struct snd_timer *timer)
966{
967 if (!timer)
968 return 0;
969
970 guard(mutex)(®ister_mutex);
971 if (! list_empty(&timer->open_list_head)) {
972 struct list_head *p, *n;
973 struct snd_timer_instance *ti;
974 pr_warn("ALSA: timer %p is busy?\n", timer);
975 list_for_each_safe(p, n, &timer->open_list_head) {
976 list_del_init(p);
977 ti = list_entry(p, struct snd_timer_instance, open_list);
978 ti->timer = NULL;
979 }
980 }
981 list_del(&timer->device_list);
982
983 if (timer->private_free)
984 timer->private_free(timer);
985 kfree(timer);
986 return 0;
987}
988
989static int snd_timer_dev_free(struct snd_device *device)
990{
991 struct snd_timer *timer = device->device_data;
992 return snd_timer_free(timer);
993}
994
995static int snd_timer_dev_register(struct snd_device *dev)
996{
997 struct snd_timer *timer = dev->device_data;
998 struct snd_timer *timer1;
999
1000 if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
1001 return -ENXIO;
1002 if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
1003 !timer->hw.resolution && timer->hw.c_resolution == NULL)
1004 return -EINVAL;
1005
1006 guard(mutex)(®ister_mutex);
1007 list_for_each_entry(timer1, &snd_timer_list, device_list) {
1008 if (timer1->tmr_class > timer->tmr_class)
1009 break;
1010 if (timer1->tmr_class < timer->tmr_class)
1011 continue;
1012 if (timer1->card && timer->card) {
1013 if (timer1->card->number > timer->card->number)
1014 break;
1015 if (timer1->card->number < timer->card->number)
1016 continue;
1017 }
1018 if (timer1->tmr_device > timer->tmr_device)
1019 break;
1020 if (timer1->tmr_device < timer->tmr_device)
1021 continue;
1022 if (timer1->tmr_subdevice > timer->tmr_subdevice)
1023 break;
1024 if (timer1->tmr_subdevice < timer->tmr_subdevice)
1025 continue;
1026 /* conflicts.. */
1027 return -EBUSY;
1028 }
1029 list_add_tail(&timer->device_list, &timer1->device_list);
1030 return 0;
1031}
1032
1033static int snd_timer_dev_disconnect(struct snd_device *device)
1034{
1035 struct snd_timer *timer = device->device_data;
1036 struct snd_timer_instance *ti;
1037
1038 guard(mutex)(®ister_mutex);
1039 list_del_init(&timer->device_list);
1040 /* wake up pending sleepers */
1041 list_for_each_entry(ti, &timer->open_list_head, open_list) {
1042 if (ti->disconnect)
1043 ti->disconnect(ti);
1044 }
1045 return 0;
1046}
1047
1048void snd_timer_notify(struct snd_timer *timer, int event, struct timespec64 *tstamp)
1049{
1050 unsigned long resolution = 0;
1051 struct snd_timer_instance *ti, *ts;
1052
1053 if (timer->card && timer->card->shutdown)
1054 return;
1055 if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
1056 return;
1057 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
1058 event > SNDRV_TIMER_EVENT_MRESUME))
1059 return;
1060 guard(spinlock_irqsave)(&timer->lock);
1061 if (event == SNDRV_TIMER_EVENT_MSTART ||
1062 event == SNDRV_TIMER_EVENT_MCONTINUE ||
1063 event == SNDRV_TIMER_EVENT_MRESUME)
1064 resolution = snd_timer_hw_resolution(timer);
1065 list_for_each_entry(ti, &timer->active_list_head, active_list) {
1066 if (ti->ccallback)
1067 ti->ccallback(ti, event, tstamp, resolution);
1068 list_for_each_entry(ts, &ti->slave_active_head, active_list)
1069 if (ts->ccallback)
1070 ts->ccallback(ts, event, tstamp, resolution);
1071 }
1072}
1073EXPORT_SYMBOL(snd_timer_notify);
1074
1075/*
1076 * exported functions for global timers
1077 */
1078int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
1079{
1080 struct snd_timer_id tid;
1081
1082 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
1083 tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1084 tid.card = -1;
1085 tid.device = device;
1086 tid.subdevice = 0;
1087 return snd_timer_new(NULL, id, &tid, rtimer);
1088}
1089EXPORT_SYMBOL(snd_timer_global_new);
1090
1091int snd_timer_global_free(struct snd_timer *timer)
1092{
1093 return snd_timer_free(timer);
1094}
1095EXPORT_SYMBOL(snd_timer_global_free);
1096
1097int snd_timer_global_register(struct snd_timer *timer)
1098{
1099 struct snd_device dev;
1100
1101 memset(&dev, 0, sizeof(dev));
1102 dev.device_data = timer;
1103 return snd_timer_dev_register(&dev);
1104}
1105EXPORT_SYMBOL(snd_timer_global_register);
1106
1107/*
1108 * System timer
1109 */
1110
1111struct snd_timer_system_private {
1112 struct timer_list tlist;
1113 struct snd_timer *snd_timer;
1114 unsigned long last_expires;
1115 unsigned long last_jiffies;
1116 unsigned long correction;
1117};
1118
1119static void snd_timer_s_function(struct timer_list *t)
1120{
1121 struct snd_timer_system_private *priv = from_timer(priv, t,
1122 tlist);
1123 struct snd_timer *timer = priv->snd_timer;
1124 unsigned long jiff = jiffies;
1125 if (time_after(jiff, priv->last_expires))
1126 priv->correction += (long)jiff - (long)priv->last_expires;
1127 snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1128}
1129
1130static int snd_timer_s_start(struct snd_timer * timer)
1131{
1132 struct snd_timer_system_private *priv;
1133 unsigned long njiff;
1134
1135 priv = (struct snd_timer_system_private *) timer->private_data;
1136 njiff = (priv->last_jiffies = jiffies);
1137 if (priv->correction > timer->sticks - 1) {
1138 priv->correction -= timer->sticks - 1;
1139 njiff++;
1140 } else {
1141 njiff += timer->sticks - priv->correction;
1142 priv->correction = 0;
1143 }
1144 priv->last_expires = njiff;
1145 mod_timer(&priv->tlist, njiff);
1146 return 0;
1147}
1148
1149static int snd_timer_s_stop(struct snd_timer * timer)
1150{
1151 struct snd_timer_system_private *priv;
1152 unsigned long jiff;
1153
1154 priv = (struct snd_timer_system_private *) timer->private_data;
1155 del_timer(&priv->tlist);
1156 jiff = jiffies;
1157 if (time_before(jiff, priv->last_expires))
1158 timer->sticks = priv->last_expires - jiff;
1159 else
1160 timer->sticks = 1;
1161 priv->correction = 0;
1162 return 0;
1163}
1164
1165static int snd_timer_s_close(struct snd_timer *timer)
1166{
1167 struct snd_timer_system_private *priv;
1168
1169 priv = (struct snd_timer_system_private *)timer->private_data;
1170 del_timer_sync(&priv->tlist);
1171 return 0;
1172}
1173
1174static const struct snd_timer_hardware snd_timer_system =
1175{
1176 .flags = SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_WORK,
1177 .resolution = NSEC_PER_SEC / HZ,
1178 .ticks = 10000000L,
1179 .close = snd_timer_s_close,
1180 .start = snd_timer_s_start,
1181 .stop = snd_timer_s_stop
1182};
1183
1184static void snd_timer_free_system(struct snd_timer *timer)
1185{
1186 kfree(timer->private_data);
1187}
1188
1189static int snd_timer_register_system(void)
1190{
1191 struct snd_timer *timer;
1192 struct snd_timer_system_private *priv;
1193 int err;
1194
1195 err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1196 if (err < 0)
1197 return err;
1198 strcpy(timer->name, "system timer");
1199 timer->hw = snd_timer_system;
1200 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1201 if (priv == NULL) {
1202 snd_timer_free(timer);
1203 return -ENOMEM;
1204 }
1205 priv->snd_timer = timer;
1206 timer_setup(&priv->tlist, snd_timer_s_function, 0);
1207 timer->private_data = priv;
1208 timer->private_free = snd_timer_free_system;
1209 return snd_timer_global_register(timer);
1210}
1211
1212#ifdef CONFIG_SND_PROC_FS
1213/*
1214 * Info interface
1215 */
1216
1217static void snd_timer_proc_read(struct snd_info_entry *entry,
1218 struct snd_info_buffer *buffer)
1219{
1220 struct snd_timer *timer;
1221 struct snd_timer_instance *ti;
1222 unsigned long resolution;
1223
1224 guard(mutex)(®ister_mutex);
1225 list_for_each_entry(timer, &snd_timer_list, device_list) {
1226 if (timer->card && timer->card->shutdown)
1227 continue;
1228 switch (timer->tmr_class) {
1229 case SNDRV_TIMER_CLASS_GLOBAL:
1230 snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1231 break;
1232 case SNDRV_TIMER_CLASS_CARD:
1233 snd_iprintf(buffer, "C%i-%i: ",
1234 timer->card->number, timer->tmr_device);
1235 break;
1236 case SNDRV_TIMER_CLASS_PCM:
1237 snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1238 timer->tmr_device, timer->tmr_subdevice);
1239 break;
1240 default:
1241 snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1242 timer->card ? timer->card->number : -1,
1243 timer->tmr_device, timer->tmr_subdevice);
1244 }
1245 snd_iprintf(buffer, "%s :", timer->name);
1246 scoped_guard(spinlock_irq, &timer->lock)
1247 resolution = snd_timer_hw_resolution(timer);
1248 if (resolution)
1249 snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1250 resolution / 1000,
1251 resolution % 1000,
1252 timer->hw.ticks);
1253 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1254 snd_iprintf(buffer, " SLAVE");
1255 snd_iprintf(buffer, "\n");
1256 list_for_each_entry(ti, &timer->open_list_head, open_list)
1257 snd_iprintf(buffer, " Client %s : %s\n",
1258 ti->owner ? ti->owner : "unknown",
1259 (ti->flags & (SNDRV_TIMER_IFLG_START |
1260 SNDRV_TIMER_IFLG_RUNNING))
1261 ? "running" : "stopped");
1262 }
1263}
1264
1265static struct snd_info_entry *snd_timer_proc_entry;
1266
1267static void __init snd_timer_proc_init(void)
1268{
1269 struct snd_info_entry *entry;
1270
1271 entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1272 if (entry != NULL) {
1273 entry->c.text.read = snd_timer_proc_read;
1274 if (snd_info_register(entry) < 0) {
1275 snd_info_free_entry(entry);
1276 entry = NULL;
1277 }
1278 }
1279 snd_timer_proc_entry = entry;
1280}
1281
1282static void __exit snd_timer_proc_done(void)
1283{
1284 snd_info_free_entry(snd_timer_proc_entry);
1285}
1286#else /* !CONFIG_SND_PROC_FS */
1287#define snd_timer_proc_init()
1288#define snd_timer_proc_done()
1289#endif
1290
1291/*
1292 * USER SPACE interface
1293 */
1294
1295static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1296 unsigned long resolution,
1297 unsigned long ticks)
1298{
1299 struct snd_timer_user *tu = timeri->callback_data;
1300 struct snd_timer_read *r;
1301 int prev;
1302
1303 guard(spinlock)(&tu->qlock);
1304 if (tu->qused > 0) {
1305 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1306 r = &tu->queue[prev];
1307 if (r->resolution == resolution) {
1308 r->ticks += ticks;
1309 goto __wake;
1310 }
1311 }
1312 if (tu->qused >= tu->queue_size) {
1313 tu->overrun++;
1314 } else {
1315 r = &tu->queue[tu->qtail++];
1316 tu->qtail %= tu->queue_size;
1317 r->resolution = resolution;
1318 r->ticks = ticks;
1319 tu->qused++;
1320 }
1321 __wake:
1322 snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1323 wake_up(&tu->qchange_sleep);
1324}
1325
1326static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1327 struct snd_timer_tread64 *tread)
1328{
1329 if (tu->qused >= tu->queue_size) {
1330 tu->overrun++;
1331 } else {
1332 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1333 tu->qtail %= tu->queue_size;
1334 tu->qused++;
1335 }
1336}
1337
1338static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1339 int event,
1340 struct timespec64 *tstamp,
1341 unsigned long resolution)
1342{
1343 struct snd_timer_user *tu = timeri->callback_data;
1344 struct snd_timer_tread64 r1;
1345
1346 if (event >= SNDRV_TIMER_EVENT_START &&
1347 event <= SNDRV_TIMER_EVENT_PAUSE)
1348 tu->tstamp = *tstamp;
1349 if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1350 return;
1351 memset(&r1, 0, sizeof(r1));
1352 r1.event = event;
1353 r1.tstamp_sec = tstamp->tv_sec;
1354 r1.tstamp_nsec = tstamp->tv_nsec;
1355 r1.val = resolution;
1356 scoped_guard(spinlock_irqsave, &tu->qlock)
1357 snd_timer_user_append_to_tqueue(tu, &r1);
1358 snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1359 wake_up(&tu->qchange_sleep);
1360}
1361
1362static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1363{
1364 struct snd_timer_user *tu = timeri->callback_data;
1365
1366 tu->disconnected = true;
1367 wake_up(&tu->qchange_sleep);
1368}
1369
1370static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1371 unsigned long resolution,
1372 unsigned long ticks)
1373{
1374 struct snd_timer_user *tu = timeri->callback_data;
1375 struct snd_timer_tread64 *r, r1;
1376 struct timespec64 tstamp;
1377 int prev, append = 0;
1378
1379 memset(&r1, 0, sizeof(r1));
1380 memset(&tstamp, 0, sizeof(tstamp));
1381 scoped_guard(spinlock, &tu->qlock) {
1382 if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1383 (1 << SNDRV_TIMER_EVENT_TICK))) == 0)
1384 return;
1385 if (tu->last_resolution != resolution || ticks > 0) {
1386 if (timer_tstamp_monotonic)
1387 ktime_get_ts64(&tstamp);
1388 else
1389 ktime_get_real_ts64(&tstamp);
1390 }
1391 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1392 tu->last_resolution != resolution) {
1393 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1394 r1.tstamp_sec = tstamp.tv_sec;
1395 r1.tstamp_nsec = tstamp.tv_nsec;
1396 r1.val = resolution;
1397 snd_timer_user_append_to_tqueue(tu, &r1);
1398 tu->last_resolution = resolution;
1399 append++;
1400 }
1401 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1402 break;
1403 if (ticks == 0)
1404 break;
1405 if (tu->qused > 0) {
1406 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1407 r = &tu->tqueue[prev];
1408 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1409 r->tstamp_sec = tstamp.tv_sec;
1410 r->tstamp_nsec = tstamp.tv_nsec;
1411 r->val += ticks;
1412 append++;
1413 break;
1414 }
1415 }
1416 r1.event = SNDRV_TIMER_EVENT_TICK;
1417 r1.tstamp_sec = tstamp.tv_sec;
1418 r1.tstamp_nsec = tstamp.tv_nsec;
1419 r1.val = ticks;
1420 snd_timer_user_append_to_tqueue(tu, &r1);
1421 append++;
1422 }
1423 if (append == 0)
1424 return;
1425 snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1426 wake_up(&tu->qchange_sleep);
1427}
1428
1429static int realloc_user_queue(struct snd_timer_user *tu, int size)
1430{
1431 struct snd_timer_read *queue = NULL;
1432 struct snd_timer_tread64 *tqueue = NULL;
1433
1434 if (tu->tread) {
1435 tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL);
1436 if (!tqueue)
1437 return -ENOMEM;
1438 } else {
1439 queue = kcalloc(size, sizeof(*queue), GFP_KERNEL);
1440 if (!queue)
1441 return -ENOMEM;
1442 }
1443
1444 guard(spinlock_irq)(&tu->qlock);
1445 kfree(tu->queue);
1446 kfree(tu->tqueue);
1447 tu->queue_size = size;
1448 tu->queue = queue;
1449 tu->tqueue = tqueue;
1450 tu->qhead = tu->qtail = tu->qused = 0;
1451
1452 return 0;
1453}
1454
1455static int snd_timer_user_open(struct inode *inode, struct file *file)
1456{
1457 struct snd_timer_user *tu;
1458 int err;
1459
1460 err = stream_open(inode, file);
1461 if (err < 0)
1462 return err;
1463
1464 tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1465 if (tu == NULL)
1466 return -ENOMEM;
1467 spin_lock_init(&tu->qlock);
1468 init_waitqueue_head(&tu->qchange_sleep);
1469 mutex_init(&tu->ioctl_lock);
1470 tu->ticks = 1;
1471 if (realloc_user_queue(tu, 128) < 0) {
1472 kfree(tu);
1473 return -ENOMEM;
1474 }
1475 file->private_data = tu;
1476 return 0;
1477}
1478
1479static int snd_timer_user_release(struct inode *inode, struct file *file)
1480{
1481 struct snd_timer_user *tu;
1482
1483 if (file->private_data) {
1484 tu = file->private_data;
1485 file->private_data = NULL;
1486 scoped_guard(mutex, &tu->ioctl_lock) {
1487 if (tu->timeri) {
1488 snd_timer_close(tu->timeri);
1489 snd_timer_instance_free(tu->timeri);
1490 }
1491 }
1492 snd_fasync_free(tu->fasync);
1493 kfree(tu->queue);
1494 kfree(tu->tqueue);
1495 kfree(tu);
1496 }
1497 return 0;
1498}
1499
1500static void snd_timer_user_zero_id(struct snd_timer_id *id)
1501{
1502 id->dev_class = SNDRV_TIMER_CLASS_NONE;
1503 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1504 id->card = -1;
1505 id->device = -1;
1506 id->subdevice = -1;
1507}
1508
1509static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1510{
1511 id->dev_class = timer->tmr_class;
1512 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1513 id->card = timer->card ? timer->card->number : -1;
1514 id->device = timer->tmr_device;
1515 id->subdevice = timer->tmr_subdevice;
1516}
1517
1518static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1519{
1520 struct snd_timer_id id;
1521 struct snd_timer *timer;
1522 struct list_head *p;
1523
1524 if (copy_from_user(&id, _tid, sizeof(id)))
1525 return -EFAULT;
1526 guard(mutex)(®ister_mutex);
1527 if (id.dev_class < 0) { /* first item */
1528 if (list_empty(&snd_timer_list))
1529 snd_timer_user_zero_id(&id);
1530 else {
1531 timer = list_entry(snd_timer_list.next,
1532 struct snd_timer, device_list);
1533 snd_timer_user_copy_id(&id, timer);
1534 }
1535 } else {
1536 switch (id.dev_class) {
1537 case SNDRV_TIMER_CLASS_GLOBAL:
1538 id.device = id.device < 0 ? 0 : id.device + 1;
1539 list_for_each(p, &snd_timer_list) {
1540 timer = list_entry(p, struct snd_timer, device_list);
1541 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1542 snd_timer_user_copy_id(&id, timer);
1543 break;
1544 }
1545 if (timer->tmr_device >= id.device) {
1546 snd_timer_user_copy_id(&id, timer);
1547 break;
1548 }
1549 }
1550 if (p == &snd_timer_list)
1551 snd_timer_user_zero_id(&id);
1552 break;
1553 case SNDRV_TIMER_CLASS_CARD:
1554 case SNDRV_TIMER_CLASS_PCM:
1555 if (id.card < 0) {
1556 id.card = 0;
1557 } else {
1558 if (id.device < 0) {
1559 id.device = 0;
1560 } else {
1561 if (id.subdevice < 0)
1562 id.subdevice = 0;
1563 else if (id.subdevice < INT_MAX)
1564 id.subdevice++;
1565 }
1566 }
1567 list_for_each(p, &snd_timer_list) {
1568 timer = list_entry(p, struct snd_timer, device_list);
1569 if (timer->tmr_class > id.dev_class) {
1570 snd_timer_user_copy_id(&id, timer);
1571 break;
1572 }
1573 if (timer->tmr_class < id.dev_class)
1574 continue;
1575 if (timer->card->number > id.card) {
1576 snd_timer_user_copy_id(&id, timer);
1577 break;
1578 }
1579 if (timer->card->number < id.card)
1580 continue;
1581 if (timer->tmr_device > id.device) {
1582 snd_timer_user_copy_id(&id, timer);
1583 break;
1584 }
1585 if (timer->tmr_device < id.device)
1586 continue;
1587 if (timer->tmr_subdevice > id.subdevice) {
1588 snd_timer_user_copy_id(&id, timer);
1589 break;
1590 }
1591 if (timer->tmr_subdevice < id.subdevice)
1592 continue;
1593 snd_timer_user_copy_id(&id, timer);
1594 break;
1595 }
1596 if (p == &snd_timer_list)
1597 snd_timer_user_zero_id(&id);
1598 break;
1599 default:
1600 snd_timer_user_zero_id(&id);
1601 }
1602 }
1603 if (copy_to_user(_tid, &id, sizeof(*_tid)))
1604 return -EFAULT;
1605 return 0;
1606}
1607
1608static int snd_timer_user_ginfo(struct file *file,
1609 struct snd_timer_ginfo __user *_ginfo)
1610{
1611 struct snd_timer_ginfo *ginfo __free(kfree) = NULL;
1612 struct snd_timer_id tid;
1613 struct snd_timer *t;
1614 struct list_head *p;
1615
1616 ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1617 if (IS_ERR(ginfo))
1618 return PTR_ERR(ginfo);
1619
1620 tid = ginfo->tid;
1621 memset(ginfo, 0, sizeof(*ginfo));
1622 ginfo->tid = tid;
1623 guard(mutex)(®ister_mutex);
1624 t = snd_timer_find(&tid);
1625 if (!t)
1626 return -ENODEV;
1627 ginfo->card = t->card ? t->card->number : -1;
1628 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1629 ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1630 strscpy(ginfo->id, t->id, sizeof(ginfo->id));
1631 strscpy(ginfo->name, t->name, sizeof(ginfo->name));
1632 scoped_guard(spinlock_irq, &t->lock)
1633 ginfo->resolution = snd_timer_hw_resolution(t);
1634 if (t->hw.resolution_min > 0) {
1635 ginfo->resolution_min = t->hw.resolution_min;
1636 ginfo->resolution_max = t->hw.resolution_max;
1637 }
1638 list_for_each(p, &t->open_list_head) {
1639 ginfo->clients++;
1640 }
1641 if (copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1642 return -EFAULT;
1643 return 0;
1644}
1645
1646static int timer_set_gparams(struct snd_timer_gparams *gparams)
1647{
1648 struct snd_timer *t;
1649
1650 guard(mutex)(®ister_mutex);
1651 t = snd_timer_find(&gparams->tid);
1652 if (!t)
1653 return -ENODEV;
1654 if (!list_empty(&t->open_list_head))
1655 return -EBUSY;
1656 if (!t->hw.set_period)
1657 return -ENOSYS;
1658 return t->hw.set_period(t, gparams->period_num, gparams->period_den);
1659}
1660
1661static int snd_timer_user_gparams(struct file *file,
1662 struct snd_timer_gparams __user *_gparams)
1663{
1664 struct snd_timer_gparams gparams;
1665
1666 if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1667 return -EFAULT;
1668 return timer_set_gparams(&gparams);
1669}
1670
1671static int snd_timer_user_gstatus(struct file *file,
1672 struct snd_timer_gstatus __user *_gstatus)
1673{
1674 struct snd_timer_gstatus gstatus;
1675 struct snd_timer_id tid;
1676 struct snd_timer *t;
1677 int err = 0;
1678
1679 if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1680 return -EFAULT;
1681 tid = gstatus.tid;
1682 memset(&gstatus, 0, sizeof(gstatus));
1683 gstatus.tid = tid;
1684 guard(mutex)(®ister_mutex);
1685 t = snd_timer_find(&tid);
1686 if (t != NULL) {
1687 guard(spinlock_irq)(&t->lock);
1688 gstatus.resolution = snd_timer_hw_resolution(t);
1689 if (t->hw.precise_resolution) {
1690 t->hw.precise_resolution(t, &gstatus.resolution_num,
1691 &gstatus.resolution_den);
1692 } else {
1693 gstatus.resolution_num = gstatus.resolution;
1694 gstatus.resolution_den = 1000000000uL;
1695 }
1696 } else {
1697 err = -ENODEV;
1698 }
1699 if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1700 err = -EFAULT;
1701 return err;
1702}
1703
1704static int snd_timer_user_tselect(struct file *file,
1705 struct snd_timer_select __user *_tselect)
1706{
1707 struct snd_timer_user *tu;
1708 struct snd_timer_select tselect;
1709 char str[32];
1710 int err = 0;
1711
1712 tu = file->private_data;
1713 if (tu->timeri) {
1714 snd_timer_close(tu->timeri);
1715 snd_timer_instance_free(tu->timeri);
1716 tu->timeri = NULL;
1717 }
1718 if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1719 err = -EFAULT;
1720 goto __err;
1721 }
1722 sprintf(str, "application %i", current->pid);
1723 if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1724 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1725 tu->timeri = snd_timer_instance_new(str);
1726 if (!tu->timeri) {
1727 err = -ENOMEM;
1728 goto __err;
1729 }
1730
1731 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1732 tu->timeri->callback = tu->tread
1733 ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1734 tu->timeri->ccallback = snd_timer_user_ccallback;
1735 tu->timeri->callback_data = (void *)tu;
1736 tu->timeri->disconnect = snd_timer_user_disconnect;
1737
1738 err = snd_timer_open(tu->timeri, &tselect.id, current->pid);
1739 if (err < 0) {
1740 snd_timer_instance_free(tu->timeri);
1741 tu->timeri = NULL;
1742 }
1743
1744 __err:
1745 return err;
1746}
1747
1748static int snd_timer_user_info(struct file *file,
1749 struct snd_timer_info __user *_info)
1750{
1751 struct snd_timer_user *tu;
1752 struct snd_timer_info *info __free(kfree) = NULL;
1753 struct snd_timer *t;
1754
1755 tu = file->private_data;
1756 if (!tu->timeri)
1757 return -EBADFD;
1758 t = tu->timeri->timer;
1759 if (!t)
1760 return -EBADFD;
1761
1762 info = kzalloc(sizeof(*info), GFP_KERNEL);
1763 if (! info)
1764 return -ENOMEM;
1765 info->card = t->card ? t->card->number : -1;
1766 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1767 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1768 strscpy(info->id, t->id, sizeof(info->id));
1769 strscpy(info->name, t->name, sizeof(info->name));
1770 scoped_guard(spinlock_irq, &t->lock)
1771 info->resolution = snd_timer_hw_resolution(t);
1772 if (copy_to_user(_info, info, sizeof(*_info)))
1773 return -EFAULT;
1774 return 0;
1775}
1776
1777static int snd_timer_user_params(struct file *file,
1778 struct snd_timer_params __user *_params)
1779{
1780 struct snd_timer_user *tu;
1781 struct snd_timer_params params;
1782 struct snd_timer *t;
1783 int err;
1784
1785 tu = file->private_data;
1786 if (!tu->timeri)
1787 return -EBADFD;
1788 t = tu->timeri->timer;
1789 if (!t)
1790 return -EBADFD;
1791 if (copy_from_user(¶ms, _params, sizeof(params)))
1792 return -EFAULT;
1793 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1794 u64 resolution;
1795
1796 if (params.ticks < 1) {
1797 err = -EINVAL;
1798 goto _end;
1799 }
1800
1801 /* Don't allow resolution less than 1ms */
1802 resolution = snd_timer_resolution(tu->timeri);
1803 resolution *= params.ticks;
1804 if (resolution < 1000000) {
1805 err = -EINVAL;
1806 goto _end;
1807 }
1808 }
1809 if (params.queue_size > 0 &&
1810 (params.queue_size < 32 || params.queue_size > 1024)) {
1811 err = -EINVAL;
1812 goto _end;
1813 }
1814 if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1815 (1<<SNDRV_TIMER_EVENT_TICK)|
1816 (1<<SNDRV_TIMER_EVENT_START)|
1817 (1<<SNDRV_TIMER_EVENT_STOP)|
1818 (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1819 (1<<SNDRV_TIMER_EVENT_PAUSE)|
1820 (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1821 (1<<SNDRV_TIMER_EVENT_RESUME)|
1822 (1<<SNDRV_TIMER_EVENT_MSTART)|
1823 (1<<SNDRV_TIMER_EVENT_MSTOP)|
1824 (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1825 (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1826 (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1827 (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1828 err = -EINVAL;
1829 goto _end;
1830 }
1831 snd_timer_stop(tu->timeri);
1832 scoped_guard(spinlock_irq, &t->lock) {
1833 tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1834 SNDRV_TIMER_IFLG_EXCLUSIVE|
1835 SNDRV_TIMER_IFLG_EARLY_EVENT);
1836 if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1837 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1838 if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1839 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1840 if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1841 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1842 }
1843 if (params.queue_size > 0 &&
1844 (unsigned int)tu->queue_size != params.queue_size) {
1845 err = realloc_user_queue(tu, params.queue_size);
1846 if (err < 0)
1847 goto _end;
1848 }
1849 scoped_guard(spinlock_irq, &tu->qlock) {
1850 tu->qhead = tu->qtail = tu->qused = 0;
1851 if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1852 if (tu->tread) {
1853 struct snd_timer_tread64 tread;
1854
1855 memset(&tread, 0, sizeof(tread));
1856 tread.event = SNDRV_TIMER_EVENT_EARLY;
1857 tread.tstamp_sec = 0;
1858 tread.tstamp_nsec = 0;
1859 tread.val = 0;
1860 snd_timer_user_append_to_tqueue(tu, &tread);
1861 } else {
1862 struct snd_timer_read *r = &tu->queue[0];
1863
1864 r->resolution = 0;
1865 r->ticks = 0;
1866 tu->qused++;
1867 tu->qtail++;
1868 }
1869 }
1870 tu->filter = params.filter;
1871 tu->ticks = params.ticks;
1872 }
1873 err = 0;
1874 _end:
1875 if (copy_to_user(_params, ¶ms, sizeof(params)))
1876 return -EFAULT;
1877 return err;
1878}
1879
1880static int snd_timer_user_status32(struct file *file,
1881 struct snd_timer_status32 __user *_status)
1882 {
1883 struct snd_timer_user *tu;
1884 struct snd_timer_status32 status;
1885
1886 tu = file->private_data;
1887 if (!tu->timeri)
1888 return -EBADFD;
1889 memset(&status, 0, sizeof(status));
1890 status.tstamp_sec = tu->tstamp.tv_sec;
1891 status.tstamp_nsec = tu->tstamp.tv_nsec;
1892 status.resolution = snd_timer_resolution(tu->timeri);
1893 status.lost = tu->timeri->lost;
1894 status.overrun = tu->overrun;
1895 scoped_guard(spinlock_irq, &tu->qlock)
1896 status.queue = tu->qused;
1897 if (copy_to_user(_status, &status, sizeof(status)))
1898 return -EFAULT;
1899 return 0;
1900}
1901
1902static int snd_timer_user_status64(struct file *file,
1903 struct snd_timer_status64 __user *_status)
1904{
1905 struct snd_timer_user *tu;
1906 struct snd_timer_status64 status;
1907
1908 tu = file->private_data;
1909 if (!tu->timeri)
1910 return -EBADFD;
1911 memset(&status, 0, sizeof(status));
1912 status.tstamp_sec = tu->tstamp.tv_sec;
1913 status.tstamp_nsec = tu->tstamp.tv_nsec;
1914 status.resolution = snd_timer_resolution(tu->timeri);
1915 status.lost = tu->timeri->lost;
1916 status.overrun = tu->overrun;
1917 scoped_guard(spinlock_irq, &tu->qlock)
1918 status.queue = tu->qused;
1919 if (copy_to_user(_status, &status, sizeof(status)))
1920 return -EFAULT;
1921 return 0;
1922}
1923
1924static int snd_timer_user_start(struct file *file)
1925{
1926 int err;
1927 struct snd_timer_user *tu;
1928
1929 tu = file->private_data;
1930 if (!tu->timeri)
1931 return -EBADFD;
1932 snd_timer_stop(tu->timeri);
1933 tu->timeri->lost = 0;
1934 tu->last_resolution = 0;
1935 err = snd_timer_start(tu->timeri, tu->ticks);
1936 if (err < 0)
1937 return err;
1938 return 0;
1939}
1940
1941static int snd_timer_user_stop(struct file *file)
1942{
1943 int err;
1944 struct snd_timer_user *tu;
1945
1946 tu = file->private_data;
1947 if (!tu->timeri)
1948 return -EBADFD;
1949 err = snd_timer_stop(tu->timeri);
1950 if (err < 0)
1951 return err;
1952 return 0;
1953}
1954
1955static int snd_timer_user_continue(struct file *file)
1956{
1957 int err;
1958 struct snd_timer_user *tu;
1959
1960 tu = file->private_data;
1961 if (!tu->timeri)
1962 return -EBADFD;
1963 /* start timer instead of continue if it's not used before */
1964 if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
1965 return snd_timer_user_start(file);
1966 tu->timeri->lost = 0;
1967 err = snd_timer_continue(tu->timeri);
1968 if (err < 0)
1969 return err;
1970 return 0;
1971}
1972
1973static int snd_timer_user_pause(struct file *file)
1974{
1975 int err;
1976 struct snd_timer_user *tu;
1977
1978 tu = file->private_data;
1979 if (!tu->timeri)
1980 return -EBADFD;
1981 err = snd_timer_pause(tu->timeri);
1982 if (err < 0)
1983 return err;
1984 return 0;
1985}
1986
1987static int snd_timer_user_tread(void __user *argp, struct snd_timer_user *tu,
1988 unsigned int cmd, bool compat)
1989{
1990 int __user *p = argp;
1991 int xarg, old_tread;
1992
1993 if (tu->timeri) /* too late */
1994 return -EBUSY;
1995 if (get_user(xarg, p))
1996 return -EFAULT;
1997
1998 old_tread = tu->tread;
1999
2000 if (!xarg)
2001 tu->tread = TREAD_FORMAT_NONE;
2002 else if (cmd == SNDRV_TIMER_IOCTL_TREAD64 ||
2003 (IS_ENABLED(CONFIG_64BIT) && !compat))
2004 tu->tread = TREAD_FORMAT_TIME64;
2005 else
2006 tu->tread = TREAD_FORMAT_TIME32;
2007
2008 if (tu->tread != old_tread &&
2009 realloc_user_queue(tu, tu->queue_size) < 0) {
2010 tu->tread = old_tread;
2011 return -ENOMEM;
2012 }
2013
2014 return 0;
2015}
2016
2017enum {
2018 SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
2019 SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
2020 SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
2021 SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
2022};
2023
2024#ifdef CONFIG_SND_UTIMER
2025/*
2026 * Since userspace-driven timers are passed to userspace, we need to have an identifier
2027 * which will allow us to use them (basically, the subdevice number of udriven timer).
2028 */
2029static DEFINE_IDA(snd_utimer_ids);
2030
2031static void snd_utimer_put_id(struct snd_utimer *utimer)
2032{
2033 int timer_id = utimer->id;
2034
2035 snd_BUG_ON(timer_id < 0 || timer_id >= SNDRV_UTIMERS_MAX_COUNT);
2036 ida_free(&snd_utimer_ids, timer_id);
2037}
2038
2039static int snd_utimer_take_id(void)
2040{
2041 return ida_alloc_max(&snd_utimer_ids, SNDRV_UTIMERS_MAX_COUNT - 1, GFP_KERNEL);
2042}
2043
2044static void snd_utimer_free(struct snd_utimer *utimer)
2045{
2046 snd_timer_free(utimer->timer);
2047 snd_utimer_put_id(utimer);
2048 kfree(utimer->name);
2049 kfree(utimer);
2050}
2051
2052static int snd_utimer_release(struct inode *inode, struct file *file)
2053{
2054 struct snd_utimer *utimer = (struct snd_utimer *)file->private_data;
2055
2056 snd_utimer_free(utimer);
2057 return 0;
2058}
2059
2060static int snd_utimer_trigger(struct file *file)
2061{
2062 struct snd_utimer *utimer = (struct snd_utimer *)file->private_data;
2063
2064 snd_timer_interrupt(utimer->timer, utimer->timer->sticks);
2065 return 0;
2066}
2067
2068static long snd_utimer_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
2069{
2070 switch (ioctl) {
2071 case SNDRV_TIMER_IOCTL_TRIGGER:
2072 return snd_utimer_trigger(file);
2073 }
2074
2075 return -ENOTTY;
2076}
2077
2078static const struct file_operations snd_utimer_fops = {
2079 .llseek = noop_llseek,
2080 .release = snd_utimer_release,
2081 .unlocked_ioctl = snd_utimer_ioctl,
2082};
2083
2084static int snd_utimer_start(struct snd_timer *t)
2085{
2086 return 0;
2087}
2088
2089static int snd_utimer_stop(struct snd_timer *t)
2090{
2091 return 0;
2092}
2093
2094static int snd_utimer_open(struct snd_timer *t)
2095{
2096 return 0;
2097}
2098
2099static int snd_utimer_close(struct snd_timer *t)
2100{
2101 return 0;
2102}
2103
2104static const struct snd_timer_hardware timer_hw = {
2105 .flags = SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_WORK,
2106 .open = snd_utimer_open,
2107 .close = snd_utimer_close,
2108 .start = snd_utimer_start,
2109 .stop = snd_utimer_stop,
2110};
2111
2112static int snd_utimer_create(struct snd_timer_uinfo *utimer_info,
2113 struct snd_utimer **r_utimer)
2114{
2115 struct snd_utimer *utimer;
2116 struct snd_timer *timer;
2117 struct snd_timer_id tid;
2118 int utimer_id;
2119 int err = 0;
2120
2121 if (!utimer_info || utimer_info->resolution == 0)
2122 return -EINVAL;
2123
2124 utimer = kzalloc(sizeof(*utimer), GFP_KERNEL);
2125 if (!utimer)
2126 return -ENOMEM;
2127
2128 /* We hold the ioctl lock here so we won't get a race condition when allocating id */
2129 utimer_id = snd_utimer_take_id();
2130 if (utimer_id < 0) {
2131 err = utimer_id;
2132 goto err_take_id;
2133 }
2134
2135 utimer->name = kasprintf(GFP_KERNEL, "snd-utimer%d", utimer_id);
2136 if (!utimer->name) {
2137 err = -ENOMEM;
2138 goto err_get_name;
2139 }
2140
2141 utimer->id = utimer_id;
2142
2143 tid.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
2144 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
2145 tid.card = -1;
2146 tid.device = SNDRV_TIMER_GLOBAL_UDRIVEN;
2147 tid.subdevice = utimer_id;
2148
2149 err = snd_timer_new(NULL, utimer->name, &tid, &timer);
2150 if (err < 0) {
2151 pr_err("Can't create userspace-driven timer\n");
2152 goto err_timer_new;
2153 }
2154
2155 timer->module = THIS_MODULE;
2156 timer->hw = timer_hw;
2157 timer->hw.resolution = utimer_info->resolution;
2158 timer->hw.ticks = 1;
2159 timer->max_instances = MAX_SLAVE_INSTANCES;
2160
2161 utimer->timer = timer;
2162
2163 err = snd_timer_global_register(timer);
2164 if (err < 0) {
2165 pr_err("Can't register a userspace-driven timer\n");
2166 goto err_timer_reg;
2167 }
2168
2169 *r_utimer = utimer;
2170 return 0;
2171
2172err_timer_reg:
2173 snd_timer_free(timer);
2174err_timer_new:
2175 kfree(utimer->name);
2176err_get_name:
2177 snd_utimer_put_id(utimer);
2178err_take_id:
2179 kfree(utimer);
2180
2181 return err;
2182}
2183
2184static int snd_utimer_ioctl_create(struct file *file,
2185 struct snd_timer_uinfo __user *_utimer_info)
2186{
2187 struct snd_utimer *utimer;
2188 struct snd_timer_uinfo *utimer_info __free(kfree) = NULL;
2189 int err, timer_fd;
2190
2191 utimer_info = memdup_user(_utimer_info, sizeof(*utimer_info));
2192 if (IS_ERR(utimer_info))
2193 return PTR_ERR(utimer_info);
2194
2195 err = snd_utimer_create(utimer_info, &utimer);
2196 if (err < 0)
2197 return err;
2198
2199 utimer_info->id = utimer->id;
2200
2201 timer_fd = anon_inode_getfd(utimer->name, &snd_utimer_fops, utimer, O_RDWR | O_CLOEXEC);
2202 if (timer_fd < 0) {
2203 snd_utimer_free(utimer);
2204 return timer_fd;
2205 }
2206
2207 utimer_info->fd = timer_fd;
2208
2209 err = copy_to_user(_utimer_info, utimer_info, sizeof(*utimer_info));
2210 if (err) {
2211 /*
2212 * "Leak" the fd, as there is nothing we can do about it.
2213 * It might have been closed already since anon_inode_getfd
2214 * makes it available for userspace.
2215 *
2216 * We have to rely on the process exit path to do any
2217 * necessary cleanup (e.g. releasing the file).
2218 */
2219 return -EFAULT;
2220 }
2221
2222 return 0;
2223}
2224
2225#else
2226
2227static int snd_utimer_ioctl_create(struct file *file,
2228 struct snd_timer_uinfo __user *_utimer_info)
2229{
2230 return -ENOTTY;
2231}
2232
2233#endif
2234
2235static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2236 unsigned long arg, bool compat)
2237{
2238 struct snd_timer_user *tu;
2239 void __user *argp = (void __user *)arg;
2240 int __user *p = argp;
2241
2242 tu = file->private_data;
2243 switch (cmd) {
2244 case SNDRV_TIMER_IOCTL_PVERSION:
2245 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
2246 case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
2247 return snd_timer_user_next_device(argp);
2248 case SNDRV_TIMER_IOCTL_TREAD_OLD:
2249 case SNDRV_TIMER_IOCTL_TREAD64:
2250 return snd_timer_user_tread(argp, tu, cmd, compat);
2251 case SNDRV_TIMER_IOCTL_GINFO:
2252 return snd_timer_user_ginfo(file, argp);
2253 case SNDRV_TIMER_IOCTL_GPARAMS:
2254 return snd_timer_user_gparams(file, argp);
2255 case SNDRV_TIMER_IOCTL_GSTATUS:
2256 return snd_timer_user_gstatus(file, argp);
2257 case SNDRV_TIMER_IOCTL_SELECT:
2258 return snd_timer_user_tselect(file, argp);
2259 case SNDRV_TIMER_IOCTL_INFO:
2260 return snd_timer_user_info(file, argp);
2261 case SNDRV_TIMER_IOCTL_PARAMS:
2262 return snd_timer_user_params(file, argp);
2263 case SNDRV_TIMER_IOCTL_STATUS32:
2264 return snd_timer_user_status32(file, argp);
2265 case SNDRV_TIMER_IOCTL_STATUS64:
2266 return snd_timer_user_status64(file, argp);
2267 case SNDRV_TIMER_IOCTL_START:
2268 case SNDRV_TIMER_IOCTL_START_OLD:
2269 return snd_timer_user_start(file);
2270 case SNDRV_TIMER_IOCTL_STOP:
2271 case SNDRV_TIMER_IOCTL_STOP_OLD:
2272 return snd_timer_user_stop(file);
2273 case SNDRV_TIMER_IOCTL_CONTINUE:
2274 case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
2275 return snd_timer_user_continue(file);
2276 case SNDRV_TIMER_IOCTL_PAUSE:
2277 case SNDRV_TIMER_IOCTL_PAUSE_OLD:
2278 return snd_timer_user_pause(file);
2279 case SNDRV_TIMER_IOCTL_CREATE:
2280 return snd_utimer_ioctl_create(file, argp);
2281 }
2282 return -ENOTTY;
2283}
2284
2285static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2286 unsigned long arg)
2287{
2288 struct snd_timer_user *tu = file->private_data;
2289
2290 guard(mutex)(&tu->ioctl_lock);
2291 return __snd_timer_user_ioctl(file, cmd, arg, false);
2292}
2293
2294static int snd_timer_user_fasync(int fd, struct file * file, int on)
2295{
2296 struct snd_timer_user *tu;
2297
2298 tu = file->private_data;
2299 return snd_fasync_helper(fd, file, on, &tu->fasync);
2300}
2301
2302static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2303 size_t count, loff_t *offset)
2304{
2305 struct snd_timer_tread64 *tread;
2306 struct snd_timer_tread32 tread32;
2307 struct snd_timer_user *tu;
2308 long result = 0, unit;
2309 int qhead;
2310 int err = 0;
2311
2312 tu = file->private_data;
2313 switch (tu->tread) {
2314 case TREAD_FORMAT_TIME64:
2315 unit = sizeof(struct snd_timer_tread64);
2316 break;
2317 case TREAD_FORMAT_TIME32:
2318 unit = sizeof(struct snd_timer_tread32);
2319 break;
2320 case TREAD_FORMAT_NONE:
2321 unit = sizeof(struct snd_timer_read);
2322 break;
2323 default:
2324 WARN_ONCE(1, "Corrupt snd_timer_user\n");
2325 return -ENOTSUPP;
2326 }
2327
2328 mutex_lock(&tu->ioctl_lock);
2329 spin_lock_irq(&tu->qlock);
2330 while ((long)count - result >= unit) {
2331 while (!tu->qused) {
2332 wait_queue_entry_t wait;
2333
2334 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2335 err = -EAGAIN;
2336 goto _error;
2337 }
2338
2339 set_current_state(TASK_INTERRUPTIBLE);
2340 init_waitqueue_entry(&wait, current);
2341 add_wait_queue(&tu->qchange_sleep, &wait);
2342
2343 spin_unlock_irq(&tu->qlock);
2344 mutex_unlock(&tu->ioctl_lock);
2345 schedule();
2346 mutex_lock(&tu->ioctl_lock);
2347 spin_lock_irq(&tu->qlock);
2348
2349 remove_wait_queue(&tu->qchange_sleep, &wait);
2350
2351 if (tu->disconnected) {
2352 err = -ENODEV;
2353 goto _error;
2354 }
2355 if (signal_pending(current)) {
2356 err = -ERESTARTSYS;
2357 goto _error;
2358 }
2359 }
2360
2361 qhead = tu->qhead++;
2362 tu->qhead %= tu->queue_size;
2363 tu->qused--;
2364 spin_unlock_irq(&tu->qlock);
2365
2366 tread = &tu->tqueue[qhead];
2367
2368 switch (tu->tread) {
2369 case TREAD_FORMAT_TIME64:
2370 if (copy_to_user(buffer, tread,
2371 sizeof(struct snd_timer_tread64)))
2372 err = -EFAULT;
2373 break;
2374 case TREAD_FORMAT_TIME32:
2375 memset(&tread32, 0, sizeof(tread32));
2376 tread32 = (struct snd_timer_tread32) {
2377 .event = tread->event,
2378 .tstamp_sec = tread->tstamp_sec,
2379 .tstamp_nsec = tread->tstamp_nsec,
2380 .val = tread->val,
2381 };
2382
2383 if (copy_to_user(buffer, &tread32, sizeof(tread32)))
2384 err = -EFAULT;
2385 break;
2386 case TREAD_FORMAT_NONE:
2387 if (copy_to_user(buffer, &tu->queue[qhead],
2388 sizeof(struct snd_timer_read)))
2389 err = -EFAULT;
2390 break;
2391 default:
2392 err = -ENOTSUPP;
2393 break;
2394 }
2395
2396 spin_lock_irq(&tu->qlock);
2397 if (err < 0)
2398 goto _error;
2399 result += unit;
2400 buffer += unit;
2401 }
2402 _error:
2403 spin_unlock_irq(&tu->qlock);
2404 mutex_unlock(&tu->ioctl_lock);
2405 return result > 0 ? result : err;
2406}
2407
2408static __poll_t snd_timer_user_poll(struct file *file, poll_table * wait)
2409{
2410 __poll_t mask;
2411 struct snd_timer_user *tu;
2412
2413 tu = file->private_data;
2414
2415 poll_wait(file, &tu->qchange_sleep, wait);
2416
2417 mask = 0;
2418 guard(spinlock_irq)(&tu->qlock);
2419 if (tu->qused)
2420 mask |= EPOLLIN | EPOLLRDNORM;
2421 if (tu->disconnected)
2422 mask |= EPOLLERR;
2423
2424 return mask;
2425}
2426
2427#ifdef CONFIG_COMPAT
2428#include "timer_compat.c"
2429#else
2430#define snd_timer_user_ioctl_compat NULL
2431#endif
2432
2433static const struct file_operations snd_timer_f_ops =
2434{
2435 .owner = THIS_MODULE,
2436 .read = snd_timer_user_read,
2437 .open = snd_timer_user_open,
2438 .release = snd_timer_user_release,
2439 .poll = snd_timer_user_poll,
2440 .unlocked_ioctl = snd_timer_user_ioctl,
2441 .compat_ioctl = snd_timer_user_ioctl_compat,
2442 .fasync = snd_timer_user_fasync,
2443};
2444
2445/* unregister the system timer */
2446static void snd_timer_free_all(void)
2447{
2448 struct snd_timer *timer, *n;
2449
2450 list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2451 snd_timer_free(timer);
2452}
2453
2454static struct device *timer_dev;
2455
2456/*
2457 * ENTRY functions
2458 */
2459
2460static int __init alsa_timer_init(void)
2461{
2462 int err;
2463
2464 err = snd_device_alloc(&timer_dev, NULL);
2465 if (err < 0)
2466 return err;
2467 dev_set_name(timer_dev, "timer");
2468
2469#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2470 snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2471 "system timer");
2472#endif
2473
2474 err = snd_timer_register_system();
2475 if (err < 0) {
2476 pr_err("ALSA: unable to register system timer (%i)\n", err);
2477 goto put_timer;
2478 }
2479
2480 err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2481 &snd_timer_f_ops, NULL, timer_dev);
2482 if (err < 0) {
2483 pr_err("ALSA: unable to register timer device (%i)\n", err);
2484 snd_timer_free_all();
2485 goto put_timer;
2486 }
2487
2488 snd_timer_proc_init();
2489 return 0;
2490
2491put_timer:
2492 put_device(timer_dev);
2493 return err;
2494}
2495
2496static void __exit alsa_timer_exit(void)
2497{
2498 snd_unregister_device(timer_dev);
2499 snd_timer_free_all();
2500 put_device(timer_dev);
2501 snd_timer_proc_done();
2502#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2503 snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2504#endif
2505}
2506
2507module_init(alsa_timer_init)
2508module_exit(alsa_timer_exit)