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