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