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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Timers abstract layer
4 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
5 */
6
7#include <linux/delay.h>
8#include <linux/init.h>
9#include <linux/slab.h>
10#include <linux/time.h>
11#include <linux/mutex.h>
12#include <linux/device.h>
13#include <linux/module.h>
14#include <linux/string.h>
15#include <linux/sched/signal.h>
16#include <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/*
2 * Timers abstract layer
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 *
20 */
21
22#include <linux/delay.h>
23#include <linux/init.h>
24#include <linux/slab.h>
25#include <linux/time.h>
26#include <linux/mutex.h>
27#include <linux/device.h>
28#include <linux/module.h>
29#include <linux/string.h>
30#include <linux/sched/signal.h>
31#include <sound/core.h>
32#include <sound/timer.h>
33#include <sound/control.h>
34#include <sound/info.h>
35#include <sound/minors.h>
36#include <sound/initval.h>
37#include <linux/kmod.h>
38
39/* internal flags */
40#define SNDRV_TIMER_IFLG_PAUSED 0x00010000
41
42#if IS_ENABLED(CONFIG_SND_HRTIMER)
43#define DEFAULT_TIMER_LIMIT 4
44#else
45#define DEFAULT_TIMER_LIMIT 1
46#endif
47
48static int timer_limit = DEFAULT_TIMER_LIMIT;
49static int timer_tstamp_monotonic = 1;
50MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>");
51MODULE_DESCRIPTION("ALSA timer interface");
52MODULE_LICENSE("GPL");
53module_param(timer_limit, int, 0444);
54MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
55module_param(timer_tstamp_monotonic, int, 0444);
56MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
57
58MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
59MODULE_ALIAS("devname:snd/timer");
60
61struct snd_timer_user {
62 struct snd_timer_instance *timeri;
63 int tread; /* enhanced read with timestamps and events */
64 unsigned long ticks;
65 unsigned long overrun;
66 int qhead;
67 int qtail;
68 int qused;
69 int queue_size;
70 bool disconnected;
71 struct snd_timer_read *queue;
72 struct snd_timer_tread *tqueue;
73 spinlock_t qlock;
74 unsigned long last_resolution;
75 unsigned int filter;
76 struct timespec tstamp; /* trigger tstamp */
77 wait_queue_head_t qchange_sleep;
78 struct fasync_struct *fasync;
79 struct mutex ioctl_lock;
80};
81
82/* list of timers */
83static LIST_HEAD(snd_timer_list);
84
85/* list of slave instances */
86static LIST_HEAD(snd_timer_slave_list);
87
88/* lock for slave active lists */
89static DEFINE_SPINLOCK(slave_active_lock);
90
91static DEFINE_MUTEX(register_mutex);
92
93static int snd_timer_free(struct snd_timer *timer);
94static int snd_timer_dev_free(struct snd_device *device);
95static int snd_timer_dev_register(struct snd_device *device);
96static int snd_timer_dev_disconnect(struct snd_device *device);
97
98static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
99
100/*
101 * create a timer instance with the given owner string.
102 * when timer is not NULL, increments the module counter
103 */
104static struct snd_timer_instance *snd_timer_instance_new(char *owner,
105 struct snd_timer *timer)
106{
107 struct snd_timer_instance *timeri;
108 timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
109 if (timeri == NULL)
110 return NULL;
111 timeri->owner = kstrdup(owner, GFP_KERNEL);
112 if (! timeri->owner) {
113 kfree(timeri);
114 return NULL;
115 }
116 INIT_LIST_HEAD(&timeri->open_list);
117 INIT_LIST_HEAD(&timeri->active_list);
118 INIT_LIST_HEAD(&timeri->ack_list);
119 INIT_LIST_HEAD(&timeri->slave_list_head);
120 INIT_LIST_HEAD(&timeri->slave_active_head);
121
122 timeri->timer = timer;
123 if (timer && !try_module_get(timer->module)) {
124 kfree(timeri->owner);
125 kfree(timeri);
126 return NULL;
127 }
128
129 return timeri;
130}
131
132/*
133 * find a timer instance from the given timer id
134 */
135static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
136{
137 struct snd_timer *timer = NULL;
138
139 list_for_each_entry(timer, &snd_timer_list, device_list) {
140 if (timer->tmr_class != tid->dev_class)
141 continue;
142 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
143 timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
144 (timer->card == NULL ||
145 timer->card->number != tid->card))
146 continue;
147 if (timer->tmr_device != tid->device)
148 continue;
149 if (timer->tmr_subdevice != tid->subdevice)
150 continue;
151 return timer;
152 }
153 return NULL;
154}
155
156#ifdef CONFIG_MODULES
157
158static void snd_timer_request(struct snd_timer_id *tid)
159{
160 switch (tid->dev_class) {
161 case SNDRV_TIMER_CLASS_GLOBAL:
162 if (tid->device < timer_limit)
163 request_module("snd-timer-%i", tid->device);
164 break;
165 case SNDRV_TIMER_CLASS_CARD:
166 case SNDRV_TIMER_CLASS_PCM:
167 if (tid->card < snd_ecards_limit)
168 request_module("snd-card-%i", tid->card);
169 break;
170 default:
171 break;
172 }
173}
174
175#endif
176
177/*
178 * look for a master instance matching with the slave id of the given slave.
179 * when found, relink the open_link of the slave.
180 *
181 * call this with register_mutex down.
182 */
183static int snd_timer_check_slave(struct snd_timer_instance *slave)
184{
185 struct snd_timer *timer;
186 struct snd_timer_instance *master;
187
188 /* FIXME: it's really dumb to look up all entries.. */
189 list_for_each_entry(timer, &snd_timer_list, device_list) {
190 list_for_each_entry(master, &timer->open_list_head, open_list) {
191 if (slave->slave_class == master->slave_class &&
192 slave->slave_id == master->slave_id) {
193 if (master->timer->num_instances >=
194 master->timer->max_instances)
195 return -EBUSY;
196 list_move_tail(&slave->open_list,
197 &master->slave_list_head);
198 master->timer->num_instances++;
199 spin_lock_irq(&slave_active_lock);
200 slave->master = master;
201 slave->timer = master->timer;
202 spin_unlock_irq(&slave_active_lock);
203 return 0;
204 }
205 }
206 }
207 return 0;
208}
209
210/*
211 * look for slave instances matching with the slave id of the given master.
212 * when found, relink the open_link of slaves.
213 *
214 * call this with register_mutex down.
215 */
216static int snd_timer_check_master(struct snd_timer_instance *master)
217{
218 struct snd_timer_instance *slave, *tmp;
219
220 /* check all pending slaves */
221 list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
222 if (slave->slave_class == master->slave_class &&
223 slave->slave_id == master->slave_id) {
224 if (master->timer->num_instances >=
225 master->timer->max_instances)
226 return -EBUSY;
227 list_move_tail(&slave->open_list, &master->slave_list_head);
228 master->timer->num_instances++;
229 spin_lock_irq(&slave_active_lock);
230 spin_lock(&master->timer->lock);
231 slave->master = master;
232 slave->timer = master->timer;
233 if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
234 list_add_tail(&slave->active_list,
235 &master->slave_active_head);
236 spin_unlock(&master->timer->lock);
237 spin_unlock_irq(&slave_active_lock);
238 }
239 }
240 return 0;
241}
242
243static int snd_timer_close_locked(struct snd_timer_instance *timeri);
244
245/*
246 * open a timer instance
247 * when opening a master, the slave id must be here given.
248 */
249int snd_timer_open(struct snd_timer_instance **ti,
250 char *owner, struct snd_timer_id *tid,
251 unsigned int slave_id)
252{
253 struct snd_timer *timer;
254 struct snd_timer_instance *timeri = NULL;
255 int err;
256
257 if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
258 /* open a slave instance */
259 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
260 tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
261 pr_debug("ALSA: timer: invalid slave class %i\n",
262 tid->dev_sclass);
263 return -EINVAL;
264 }
265 mutex_lock(®ister_mutex);
266 timeri = snd_timer_instance_new(owner, NULL);
267 if (!timeri) {
268 mutex_unlock(®ister_mutex);
269 return -ENOMEM;
270 }
271 timeri->slave_class = tid->dev_sclass;
272 timeri->slave_id = tid->device;
273 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
274 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
275 err = snd_timer_check_slave(timeri);
276 if (err < 0) {
277 snd_timer_close_locked(timeri);
278 timeri = NULL;
279 }
280 mutex_unlock(®ister_mutex);
281 *ti = timeri;
282 return err;
283 }
284
285 /* open a master instance */
286 mutex_lock(®ister_mutex);
287 timer = snd_timer_find(tid);
288#ifdef CONFIG_MODULES
289 if (!timer) {
290 mutex_unlock(®ister_mutex);
291 snd_timer_request(tid);
292 mutex_lock(®ister_mutex);
293 timer = snd_timer_find(tid);
294 }
295#endif
296 if (!timer) {
297 mutex_unlock(®ister_mutex);
298 return -ENODEV;
299 }
300 if (!list_empty(&timer->open_list_head)) {
301 timeri = list_entry(timer->open_list_head.next,
302 struct snd_timer_instance, open_list);
303 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
304 mutex_unlock(®ister_mutex);
305 return -EBUSY;
306 }
307 }
308 if (timer->num_instances >= timer->max_instances) {
309 mutex_unlock(®ister_mutex);
310 return -EBUSY;
311 }
312 timeri = snd_timer_instance_new(owner, timer);
313 if (!timeri) {
314 mutex_unlock(®ister_mutex);
315 return -ENOMEM;
316 }
317 /* take a card refcount for safe disconnection */
318 if (timer->card)
319 get_device(&timer->card->card_dev);
320 timeri->slave_class = tid->dev_sclass;
321 timeri->slave_id = slave_id;
322
323 if (list_empty(&timer->open_list_head) && timer->hw.open) {
324 int err = timer->hw.open(timer);
325 if (err) {
326 kfree(timeri->owner);
327 kfree(timeri);
328
329 if (timer->card)
330 put_device(&timer->card->card_dev);
331 module_put(timer->module);
332 mutex_unlock(®ister_mutex);
333 return err;
334 }
335 }
336
337 list_add_tail(&timeri->open_list, &timer->open_list_head);
338 timer->num_instances++;
339 err = snd_timer_check_master(timeri);
340 if (err < 0) {
341 snd_timer_close_locked(timeri);
342 timeri = NULL;
343 }
344 mutex_unlock(®ister_mutex);
345 *ti = timeri;
346 return err;
347}
348EXPORT_SYMBOL(snd_timer_open);
349
350/*
351 * close a timer instance
352 * call this with register_mutex down.
353 */
354static int snd_timer_close_locked(struct snd_timer_instance *timeri)
355{
356 struct snd_timer *timer = NULL;
357 struct snd_timer_instance *slave, *tmp;
358
359 list_del(&timeri->open_list);
360
361 /* force to stop the timer */
362 snd_timer_stop(timeri);
363
364 timer = timeri->timer;
365 if (timer) {
366 timer->num_instances--;
367 /* wait, until the active callback is finished */
368 spin_lock_irq(&timer->lock);
369 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
370 spin_unlock_irq(&timer->lock);
371 udelay(10);
372 spin_lock_irq(&timer->lock);
373 }
374 spin_unlock_irq(&timer->lock);
375
376 /* remove slave links */
377 spin_lock_irq(&slave_active_lock);
378 spin_lock(&timer->lock);
379 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
380 open_list) {
381 list_move_tail(&slave->open_list, &snd_timer_slave_list);
382 timer->num_instances--;
383 slave->master = NULL;
384 slave->timer = NULL;
385 list_del_init(&slave->ack_list);
386 list_del_init(&slave->active_list);
387 }
388 spin_unlock(&timer->lock);
389 spin_unlock_irq(&slave_active_lock);
390
391 /* slave doesn't need to release timer resources below */
392 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
393 timer = NULL;
394 }
395
396 if (timeri->private_free)
397 timeri->private_free(timeri);
398 kfree(timeri->owner);
399 kfree(timeri);
400
401 if (timer) {
402 if (list_empty(&timer->open_list_head) && timer->hw.close)
403 timer->hw.close(timer);
404 /* release a card refcount for safe disconnection */
405 if (timer->card)
406 put_device(&timer->card->card_dev);
407 module_put(timer->module);
408 }
409
410 return 0;
411}
412
413/*
414 * close a timer instance
415 */
416int snd_timer_close(struct snd_timer_instance *timeri)
417{
418 int err;
419
420 if (snd_BUG_ON(!timeri))
421 return -ENXIO;
422
423 mutex_lock(®ister_mutex);
424 err = snd_timer_close_locked(timeri);
425 mutex_unlock(®ister_mutex);
426 return err;
427}
428EXPORT_SYMBOL(snd_timer_close);
429
430unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
431{
432 struct snd_timer * timer;
433
434 if (timeri == NULL)
435 return 0;
436 timer = timeri->timer;
437 if (timer) {
438 if (timer->hw.c_resolution)
439 return timer->hw.c_resolution(timer);
440 return timer->hw.resolution;
441 }
442 return 0;
443}
444EXPORT_SYMBOL(snd_timer_resolution);
445
446static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
447{
448 struct snd_timer *timer;
449 unsigned long resolution = 0;
450 struct snd_timer_instance *ts;
451 struct timespec tstamp;
452
453 if (timer_tstamp_monotonic)
454 ktime_get_ts(&tstamp);
455 else
456 getnstimeofday(&tstamp);
457 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
458 event > SNDRV_TIMER_EVENT_PAUSE))
459 return;
460 if (event == SNDRV_TIMER_EVENT_START ||
461 event == SNDRV_TIMER_EVENT_CONTINUE)
462 resolution = snd_timer_resolution(ti);
463 if (ti->ccallback)
464 ti->ccallback(ti, event, &tstamp, resolution);
465 if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
466 return;
467 timer = ti->timer;
468 if (timer == NULL)
469 return;
470 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
471 return;
472 list_for_each_entry(ts, &ti->slave_active_head, active_list)
473 if (ts->ccallback)
474 ts->ccallback(ts, event + 100, &tstamp, resolution);
475}
476
477/* start/continue a master timer */
478static int snd_timer_start1(struct snd_timer_instance *timeri,
479 bool start, unsigned long ticks)
480{
481 struct snd_timer *timer;
482 int result;
483 unsigned long flags;
484
485 timer = timeri->timer;
486 if (!timer)
487 return -EINVAL;
488
489 spin_lock_irqsave(&timer->lock, flags);
490 if (timer->card && timer->card->shutdown) {
491 result = -ENODEV;
492 goto unlock;
493 }
494 if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
495 SNDRV_TIMER_IFLG_START)) {
496 result = -EBUSY;
497 goto unlock;
498 }
499
500 if (start)
501 timeri->ticks = timeri->cticks = ticks;
502 else if (!timeri->cticks)
503 timeri->cticks = 1;
504 timeri->pticks = 0;
505
506 list_move_tail(&timeri->active_list, &timer->active_list_head);
507 if (timer->running) {
508 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
509 goto __start_now;
510 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
511 timeri->flags |= SNDRV_TIMER_IFLG_START;
512 result = 1; /* delayed start */
513 } else {
514 if (start)
515 timer->sticks = ticks;
516 timer->hw.start(timer);
517 __start_now:
518 timer->running++;
519 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
520 result = 0;
521 }
522 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
523 SNDRV_TIMER_EVENT_CONTINUE);
524 unlock:
525 spin_unlock_irqrestore(&timer->lock, flags);
526 return result;
527}
528
529/* start/continue a slave timer */
530static int snd_timer_start_slave(struct snd_timer_instance *timeri,
531 bool start)
532{
533 unsigned long flags;
534
535 spin_lock_irqsave(&slave_active_lock, flags);
536 if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) {
537 spin_unlock_irqrestore(&slave_active_lock, flags);
538 return -EBUSY;
539 }
540 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
541 if (timeri->master && timeri->timer) {
542 spin_lock(&timeri->timer->lock);
543 list_add_tail(&timeri->active_list,
544 &timeri->master->slave_active_head);
545 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
546 SNDRV_TIMER_EVENT_CONTINUE);
547 spin_unlock(&timeri->timer->lock);
548 }
549 spin_unlock_irqrestore(&slave_active_lock, flags);
550 return 1; /* delayed start */
551}
552
553/* stop/pause a master timer */
554static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
555{
556 struct snd_timer *timer;
557 int result = 0;
558 unsigned long flags;
559
560 timer = timeri->timer;
561 if (!timer)
562 return -EINVAL;
563 spin_lock_irqsave(&timer->lock, flags);
564 if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
565 SNDRV_TIMER_IFLG_START))) {
566 result = -EBUSY;
567 goto unlock;
568 }
569 list_del_init(&timeri->ack_list);
570 list_del_init(&timeri->active_list);
571 if (timer->card && timer->card->shutdown)
572 goto unlock;
573 if (stop) {
574 timeri->cticks = timeri->ticks;
575 timeri->pticks = 0;
576 }
577 if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
578 !(--timer->running)) {
579 timer->hw.stop(timer);
580 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
581 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
582 snd_timer_reschedule(timer, 0);
583 if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
584 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
585 timer->hw.start(timer);
586 }
587 }
588 }
589 timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
590 if (stop)
591 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
592 else
593 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
594 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
595 SNDRV_TIMER_EVENT_PAUSE);
596 unlock:
597 spin_unlock_irqrestore(&timer->lock, flags);
598 return result;
599}
600
601/* stop/pause a slave timer */
602static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
603{
604 unsigned long flags;
605
606 spin_lock_irqsave(&slave_active_lock, flags);
607 if (!(timeri->flags & SNDRV_TIMER_IFLG_RUNNING)) {
608 spin_unlock_irqrestore(&slave_active_lock, flags);
609 return -EBUSY;
610 }
611 timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
612 if (timeri->timer) {
613 spin_lock(&timeri->timer->lock);
614 list_del_init(&timeri->ack_list);
615 list_del_init(&timeri->active_list);
616 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
617 SNDRV_TIMER_EVENT_PAUSE);
618 spin_unlock(&timeri->timer->lock);
619 }
620 spin_unlock_irqrestore(&slave_active_lock, flags);
621 return 0;
622}
623
624/*
625 * start the timer instance
626 */
627int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
628{
629 if (timeri == NULL || ticks < 1)
630 return -EINVAL;
631 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
632 return snd_timer_start_slave(timeri, true);
633 else
634 return snd_timer_start1(timeri, true, ticks);
635}
636EXPORT_SYMBOL(snd_timer_start);
637
638/*
639 * stop the timer instance.
640 *
641 * do not call this from the timer callback!
642 */
643int snd_timer_stop(struct snd_timer_instance *timeri)
644{
645 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
646 return snd_timer_stop_slave(timeri, true);
647 else
648 return snd_timer_stop1(timeri, true);
649}
650EXPORT_SYMBOL(snd_timer_stop);
651
652/*
653 * start again.. the tick is kept.
654 */
655int snd_timer_continue(struct snd_timer_instance *timeri)
656{
657 /* timer can continue only after pause */
658 if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
659 return -EINVAL;
660
661 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
662 return snd_timer_start_slave(timeri, false);
663 else
664 return snd_timer_start1(timeri, false, 0);
665}
666EXPORT_SYMBOL(snd_timer_continue);
667
668/*
669 * pause.. remember the ticks left
670 */
671int snd_timer_pause(struct snd_timer_instance * timeri)
672{
673 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
674 return snd_timer_stop_slave(timeri, false);
675 else
676 return snd_timer_stop1(timeri, false);
677}
678EXPORT_SYMBOL(snd_timer_pause);
679
680/*
681 * reschedule the timer
682 *
683 * start pending instances and check the scheduling ticks.
684 * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
685 */
686static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
687{
688 struct snd_timer_instance *ti;
689 unsigned long ticks = ~0UL;
690
691 list_for_each_entry(ti, &timer->active_list_head, active_list) {
692 if (ti->flags & SNDRV_TIMER_IFLG_START) {
693 ti->flags &= ~SNDRV_TIMER_IFLG_START;
694 ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
695 timer->running++;
696 }
697 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
698 if (ticks > ti->cticks)
699 ticks = ti->cticks;
700 }
701 }
702 if (ticks == ~0UL) {
703 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
704 return;
705 }
706 if (ticks > timer->hw.ticks)
707 ticks = timer->hw.ticks;
708 if (ticks_left != ticks)
709 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
710 timer->sticks = ticks;
711}
712
713/*
714 * timer tasklet
715 *
716 */
717static void snd_timer_tasklet(unsigned long arg)
718{
719 struct snd_timer *timer = (struct snd_timer *) arg;
720 struct snd_timer_instance *ti;
721 struct list_head *p;
722 unsigned long resolution, ticks;
723 unsigned long flags;
724
725 if (timer->card && timer->card->shutdown)
726 return;
727
728 spin_lock_irqsave(&timer->lock, flags);
729 /* now process all callbacks */
730 while (!list_empty(&timer->sack_list_head)) {
731 p = timer->sack_list_head.next; /* get first item */
732 ti = list_entry(p, struct snd_timer_instance, ack_list);
733
734 /* remove from ack_list and make empty */
735 list_del_init(p);
736
737 ticks = ti->pticks;
738 ti->pticks = 0;
739 resolution = ti->resolution;
740
741 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
742 spin_unlock(&timer->lock);
743 if (ti->callback)
744 ti->callback(ti, resolution, ticks);
745 spin_lock(&timer->lock);
746 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
747 }
748 spin_unlock_irqrestore(&timer->lock, flags);
749}
750
751/*
752 * timer interrupt
753 *
754 * ticks_left is usually equal to timer->sticks.
755 *
756 */
757void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
758{
759 struct snd_timer_instance *ti, *ts, *tmp;
760 unsigned long resolution, ticks;
761 struct list_head *p, *ack_list_head;
762 unsigned long flags;
763 int use_tasklet = 0;
764
765 if (timer == NULL)
766 return;
767
768 if (timer->card && timer->card->shutdown)
769 return;
770
771 spin_lock_irqsave(&timer->lock, flags);
772
773 /* remember the current resolution */
774 if (timer->hw.c_resolution)
775 resolution = timer->hw.c_resolution(timer);
776 else
777 resolution = timer->hw.resolution;
778
779 /* loop for all active instances
780 * Here we cannot use list_for_each_entry because the active_list of a
781 * processed instance is relinked to done_list_head before the callback
782 * is called.
783 */
784 list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
785 active_list) {
786 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
787 continue;
788 ti->pticks += ticks_left;
789 ti->resolution = resolution;
790 if (ti->cticks < ticks_left)
791 ti->cticks = 0;
792 else
793 ti->cticks -= ticks_left;
794 if (ti->cticks) /* not expired */
795 continue;
796 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
797 ti->cticks = ti->ticks;
798 } else {
799 ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
800 --timer->running;
801 list_del_init(&ti->active_list);
802 }
803 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
804 (ti->flags & SNDRV_TIMER_IFLG_FAST))
805 ack_list_head = &timer->ack_list_head;
806 else
807 ack_list_head = &timer->sack_list_head;
808 if (list_empty(&ti->ack_list))
809 list_add_tail(&ti->ack_list, ack_list_head);
810 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
811 ts->pticks = ti->pticks;
812 ts->resolution = resolution;
813 if (list_empty(&ts->ack_list))
814 list_add_tail(&ts->ack_list, ack_list_head);
815 }
816 }
817 if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
818 snd_timer_reschedule(timer, timer->sticks);
819 if (timer->running) {
820 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
821 timer->hw.stop(timer);
822 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
823 }
824 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
825 (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
826 /* restart timer */
827 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
828 timer->hw.start(timer);
829 }
830 } else {
831 timer->hw.stop(timer);
832 }
833
834 /* now process all fast callbacks */
835 while (!list_empty(&timer->ack_list_head)) {
836 p = timer->ack_list_head.next; /* get first item */
837 ti = list_entry(p, struct snd_timer_instance, ack_list);
838
839 /* remove from ack_list and make empty */
840 list_del_init(p);
841
842 ticks = ti->pticks;
843 ti->pticks = 0;
844
845 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
846 spin_unlock(&timer->lock);
847 if (ti->callback)
848 ti->callback(ti, resolution, ticks);
849 spin_lock(&timer->lock);
850 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
851 }
852
853 /* do we have any slow callbacks? */
854 use_tasklet = !list_empty(&timer->sack_list_head);
855 spin_unlock_irqrestore(&timer->lock, flags);
856
857 if (use_tasklet)
858 tasklet_schedule(&timer->task_queue);
859}
860EXPORT_SYMBOL(snd_timer_interrupt);
861
862/*
863
864 */
865
866int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
867 struct snd_timer **rtimer)
868{
869 struct snd_timer *timer;
870 int err;
871 static struct snd_device_ops ops = {
872 .dev_free = snd_timer_dev_free,
873 .dev_register = snd_timer_dev_register,
874 .dev_disconnect = snd_timer_dev_disconnect,
875 };
876
877 if (snd_BUG_ON(!tid))
878 return -EINVAL;
879 if (rtimer)
880 *rtimer = NULL;
881 timer = kzalloc(sizeof(*timer), GFP_KERNEL);
882 if (!timer)
883 return -ENOMEM;
884 timer->tmr_class = tid->dev_class;
885 timer->card = card;
886 timer->tmr_device = tid->device;
887 timer->tmr_subdevice = tid->subdevice;
888 if (id)
889 strlcpy(timer->id, id, sizeof(timer->id));
890 timer->sticks = 1;
891 INIT_LIST_HEAD(&timer->device_list);
892 INIT_LIST_HEAD(&timer->open_list_head);
893 INIT_LIST_HEAD(&timer->active_list_head);
894 INIT_LIST_HEAD(&timer->ack_list_head);
895 INIT_LIST_HEAD(&timer->sack_list_head);
896 spin_lock_init(&timer->lock);
897 tasklet_init(&timer->task_queue, snd_timer_tasklet,
898 (unsigned long)timer);
899 timer->max_instances = 1000; /* default limit per timer */
900 if (card != NULL) {
901 timer->module = card->module;
902 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
903 if (err < 0) {
904 snd_timer_free(timer);
905 return err;
906 }
907 }
908 if (rtimer)
909 *rtimer = timer;
910 return 0;
911}
912EXPORT_SYMBOL(snd_timer_new);
913
914static int snd_timer_free(struct snd_timer *timer)
915{
916 if (!timer)
917 return 0;
918
919 mutex_lock(®ister_mutex);
920 if (! list_empty(&timer->open_list_head)) {
921 struct list_head *p, *n;
922 struct snd_timer_instance *ti;
923 pr_warn("ALSA: timer %p is busy?\n", timer);
924 list_for_each_safe(p, n, &timer->open_list_head) {
925 list_del_init(p);
926 ti = list_entry(p, struct snd_timer_instance, open_list);
927 ti->timer = NULL;
928 }
929 }
930 list_del(&timer->device_list);
931 mutex_unlock(®ister_mutex);
932
933 if (timer->private_free)
934 timer->private_free(timer);
935 kfree(timer);
936 return 0;
937}
938
939static int snd_timer_dev_free(struct snd_device *device)
940{
941 struct snd_timer *timer = device->device_data;
942 return snd_timer_free(timer);
943}
944
945static int snd_timer_dev_register(struct snd_device *dev)
946{
947 struct snd_timer *timer = dev->device_data;
948 struct snd_timer *timer1;
949
950 if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
951 return -ENXIO;
952 if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
953 !timer->hw.resolution && timer->hw.c_resolution == NULL)
954 return -EINVAL;
955
956 mutex_lock(®ister_mutex);
957 list_for_each_entry(timer1, &snd_timer_list, device_list) {
958 if (timer1->tmr_class > timer->tmr_class)
959 break;
960 if (timer1->tmr_class < timer->tmr_class)
961 continue;
962 if (timer1->card && timer->card) {
963 if (timer1->card->number > timer->card->number)
964 break;
965 if (timer1->card->number < timer->card->number)
966 continue;
967 }
968 if (timer1->tmr_device > timer->tmr_device)
969 break;
970 if (timer1->tmr_device < timer->tmr_device)
971 continue;
972 if (timer1->tmr_subdevice > timer->tmr_subdevice)
973 break;
974 if (timer1->tmr_subdevice < timer->tmr_subdevice)
975 continue;
976 /* conflicts.. */
977 mutex_unlock(®ister_mutex);
978 return -EBUSY;
979 }
980 list_add_tail(&timer->device_list, &timer1->device_list);
981 mutex_unlock(®ister_mutex);
982 return 0;
983}
984
985static int snd_timer_dev_disconnect(struct snd_device *device)
986{
987 struct snd_timer *timer = device->device_data;
988 struct snd_timer_instance *ti;
989
990 mutex_lock(®ister_mutex);
991 list_del_init(&timer->device_list);
992 /* wake up pending sleepers */
993 list_for_each_entry(ti, &timer->open_list_head, open_list) {
994 if (ti->disconnect)
995 ti->disconnect(ti);
996 }
997 mutex_unlock(®ister_mutex);
998 return 0;
999}
1000
1001void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
1002{
1003 unsigned long flags;
1004 unsigned long resolution = 0;
1005 struct snd_timer_instance *ti, *ts;
1006
1007 if (timer->card && timer->card->shutdown)
1008 return;
1009 if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
1010 return;
1011 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
1012 event > SNDRV_TIMER_EVENT_MRESUME))
1013 return;
1014 spin_lock_irqsave(&timer->lock, flags);
1015 if (event == SNDRV_TIMER_EVENT_MSTART ||
1016 event == SNDRV_TIMER_EVENT_MCONTINUE ||
1017 event == SNDRV_TIMER_EVENT_MRESUME) {
1018 if (timer->hw.c_resolution)
1019 resolution = timer->hw.c_resolution(timer);
1020 else
1021 resolution = timer->hw.resolution;
1022 }
1023 list_for_each_entry(ti, &timer->active_list_head, active_list) {
1024 if (ti->ccallback)
1025 ti->ccallback(ti, event, tstamp, resolution);
1026 list_for_each_entry(ts, &ti->slave_active_head, active_list)
1027 if (ts->ccallback)
1028 ts->ccallback(ts, event, tstamp, resolution);
1029 }
1030 spin_unlock_irqrestore(&timer->lock, flags);
1031}
1032EXPORT_SYMBOL(snd_timer_notify);
1033
1034/*
1035 * exported functions for global timers
1036 */
1037int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
1038{
1039 struct snd_timer_id tid;
1040
1041 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
1042 tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1043 tid.card = -1;
1044 tid.device = device;
1045 tid.subdevice = 0;
1046 return snd_timer_new(NULL, id, &tid, rtimer);
1047}
1048EXPORT_SYMBOL(snd_timer_global_new);
1049
1050int snd_timer_global_free(struct snd_timer *timer)
1051{
1052 return snd_timer_free(timer);
1053}
1054EXPORT_SYMBOL(snd_timer_global_free);
1055
1056int snd_timer_global_register(struct snd_timer *timer)
1057{
1058 struct snd_device dev;
1059
1060 memset(&dev, 0, sizeof(dev));
1061 dev.device_data = timer;
1062 return snd_timer_dev_register(&dev);
1063}
1064EXPORT_SYMBOL(snd_timer_global_register);
1065
1066/*
1067 * System timer
1068 */
1069
1070struct snd_timer_system_private {
1071 struct timer_list tlist;
1072 struct snd_timer *snd_timer;
1073 unsigned long last_expires;
1074 unsigned long last_jiffies;
1075 unsigned long correction;
1076};
1077
1078static void snd_timer_s_function(struct timer_list *t)
1079{
1080 struct snd_timer_system_private *priv = from_timer(priv, t,
1081 tlist);
1082 struct snd_timer *timer = priv->snd_timer;
1083 unsigned long jiff = jiffies;
1084 if (time_after(jiff, priv->last_expires))
1085 priv->correction += (long)jiff - (long)priv->last_expires;
1086 snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1087}
1088
1089static int snd_timer_s_start(struct snd_timer * timer)
1090{
1091 struct snd_timer_system_private *priv;
1092 unsigned long njiff;
1093
1094 priv = (struct snd_timer_system_private *) timer->private_data;
1095 njiff = (priv->last_jiffies = jiffies);
1096 if (priv->correction > timer->sticks - 1) {
1097 priv->correction -= timer->sticks - 1;
1098 njiff++;
1099 } else {
1100 njiff += timer->sticks - priv->correction;
1101 priv->correction = 0;
1102 }
1103 priv->last_expires = njiff;
1104 mod_timer(&priv->tlist, njiff);
1105 return 0;
1106}
1107
1108static int snd_timer_s_stop(struct snd_timer * timer)
1109{
1110 struct snd_timer_system_private *priv;
1111 unsigned long jiff;
1112
1113 priv = (struct snd_timer_system_private *) timer->private_data;
1114 del_timer(&priv->tlist);
1115 jiff = jiffies;
1116 if (time_before(jiff, priv->last_expires))
1117 timer->sticks = priv->last_expires - jiff;
1118 else
1119 timer->sticks = 1;
1120 priv->correction = 0;
1121 return 0;
1122}
1123
1124static int snd_timer_s_close(struct snd_timer *timer)
1125{
1126 struct snd_timer_system_private *priv;
1127
1128 priv = (struct snd_timer_system_private *)timer->private_data;
1129 del_timer_sync(&priv->tlist);
1130 return 0;
1131}
1132
1133static struct snd_timer_hardware snd_timer_system =
1134{
1135 .flags = SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
1136 .resolution = 1000000000L / HZ,
1137 .ticks = 10000000L,
1138 .close = snd_timer_s_close,
1139 .start = snd_timer_s_start,
1140 .stop = snd_timer_s_stop
1141};
1142
1143static void snd_timer_free_system(struct snd_timer *timer)
1144{
1145 kfree(timer->private_data);
1146}
1147
1148static int snd_timer_register_system(void)
1149{
1150 struct snd_timer *timer;
1151 struct snd_timer_system_private *priv;
1152 int err;
1153
1154 err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1155 if (err < 0)
1156 return err;
1157 strcpy(timer->name, "system timer");
1158 timer->hw = snd_timer_system;
1159 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1160 if (priv == NULL) {
1161 snd_timer_free(timer);
1162 return -ENOMEM;
1163 }
1164 priv->snd_timer = timer;
1165 timer_setup(&priv->tlist, snd_timer_s_function, 0);
1166 timer->private_data = priv;
1167 timer->private_free = snd_timer_free_system;
1168 return snd_timer_global_register(timer);
1169}
1170
1171#ifdef CONFIG_SND_PROC_FS
1172/*
1173 * Info interface
1174 */
1175
1176static void snd_timer_proc_read(struct snd_info_entry *entry,
1177 struct snd_info_buffer *buffer)
1178{
1179 struct snd_timer *timer;
1180 struct snd_timer_instance *ti;
1181
1182 mutex_lock(®ister_mutex);
1183 list_for_each_entry(timer, &snd_timer_list, device_list) {
1184 if (timer->card && timer->card->shutdown)
1185 continue;
1186 switch (timer->tmr_class) {
1187 case SNDRV_TIMER_CLASS_GLOBAL:
1188 snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1189 break;
1190 case SNDRV_TIMER_CLASS_CARD:
1191 snd_iprintf(buffer, "C%i-%i: ",
1192 timer->card->number, timer->tmr_device);
1193 break;
1194 case SNDRV_TIMER_CLASS_PCM:
1195 snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1196 timer->tmr_device, timer->tmr_subdevice);
1197 break;
1198 default:
1199 snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1200 timer->card ? timer->card->number : -1,
1201 timer->tmr_device, timer->tmr_subdevice);
1202 }
1203 snd_iprintf(buffer, "%s :", timer->name);
1204 if (timer->hw.resolution)
1205 snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1206 timer->hw.resolution / 1000,
1207 timer->hw.resolution % 1000,
1208 timer->hw.ticks);
1209 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1210 snd_iprintf(buffer, " SLAVE");
1211 snd_iprintf(buffer, "\n");
1212 list_for_each_entry(ti, &timer->open_list_head, open_list)
1213 snd_iprintf(buffer, " Client %s : %s\n",
1214 ti->owner ? ti->owner : "unknown",
1215 ti->flags & (SNDRV_TIMER_IFLG_START |
1216 SNDRV_TIMER_IFLG_RUNNING)
1217 ? "running" : "stopped");
1218 }
1219 mutex_unlock(®ister_mutex);
1220}
1221
1222static struct snd_info_entry *snd_timer_proc_entry;
1223
1224static void __init snd_timer_proc_init(void)
1225{
1226 struct snd_info_entry *entry;
1227
1228 entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1229 if (entry != NULL) {
1230 entry->c.text.read = snd_timer_proc_read;
1231 if (snd_info_register(entry) < 0) {
1232 snd_info_free_entry(entry);
1233 entry = NULL;
1234 }
1235 }
1236 snd_timer_proc_entry = entry;
1237}
1238
1239static void __exit snd_timer_proc_done(void)
1240{
1241 snd_info_free_entry(snd_timer_proc_entry);
1242}
1243#else /* !CONFIG_SND_PROC_FS */
1244#define snd_timer_proc_init()
1245#define snd_timer_proc_done()
1246#endif
1247
1248/*
1249 * USER SPACE interface
1250 */
1251
1252static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1253 unsigned long resolution,
1254 unsigned long ticks)
1255{
1256 struct snd_timer_user *tu = timeri->callback_data;
1257 struct snd_timer_read *r;
1258 int prev;
1259
1260 spin_lock(&tu->qlock);
1261 if (tu->qused > 0) {
1262 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1263 r = &tu->queue[prev];
1264 if (r->resolution == resolution) {
1265 r->ticks += ticks;
1266 goto __wake;
1267 }
1268 }
1269 if (tu->qused >= tu->queue_size) {
1270 tu->overrun++;
1271 } else {
1272 r = &tu->queue[tu->qtail++];
1273 tu->qtail %= tu->queue_size;
1274 r->resolution = resolution;
1275 r->ticks = ticks;
1276 tu->qused++;
1277 }
1278 __wake:
1279 spin_unlock(&tu->qlock);
1280 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1281 wake_up(&tu->qchange_sleep);
1282}
1283
1284static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1285 struct snd_timer_tread *tread)
1286{
1287 if (tu->qused >= tu->queue_size) {
1288 tu->overrun++;
1289 } else {
1290 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1291 tu->qtail %= tu->queue_size;
1292 tu->qused++;
1293 }
1294}
1295
1296static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1297 int event,
1298 struct timespec *tstamp,
1299 unsigned long resolution)
1300{
1301 struct snd_timer_user *tu = timeri->callback_data;
1302 struct snd_timer_tread r1;
1303 unsigned long flags;
1304
1305 if (event >= SNDRV_TIMER_EVENT_START &&
1306 event <= SNDRV_TIMER_EVENT_PAUSE)
1307 tu->tstamp = *tstamp;
1308 if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1309 return;
1310 memset(&r1, 0, sizeof(r1));
1311 r1.event = event;
1312 r1.tstamp = *tstamp;
1313 r1.val = resolution;
1314 spin_lock_irqsave(&tu->qlock, flags);
1315 snd_timer_user_append_to_tqueue(tu, &r1);
1316 spin_unlock_irqrestore(&tu->qlock, flags);
1317 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1318 wake_up(&tu->qchange_sleep);
1319}
1320
1321static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1322{
1323 struct snd_timer_user *tu = timeri->callback_data;
1324
1325 tu->disconnected = true;
1326 wake_up(&tu->qchange_sleep);
1327}
1328
1329static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1330 unsigned long resolution,
1331 unsigned long ticks)
1332{
1333 struct snd_timer_user *tu = timeri->callback_data;
1334 struct snd_timer_tread *r, r1;
1335 struct timespec tstamp;
1336 int prev, append = 0;
1337
1338 memset(&r1, 0, sizeof(r1));
1339 memset(&tstamp, 0, sizeof(tstamp));
1340 spin_lock(&tu->qlock);
1341 if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1342 (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1343 spin_unlock(&tu->qlock);
1344 return;
1345 }
1346 if (tu->last_resolution != resolution || ticks > 0) {
1347 if (timer_tstamp_monotonic)
1348 ktime_get_ts(&tstamp);
1349 else
1350 getnstimeofday(&tstamp);
1351 }
1352 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1353 tu->last_resolution != resolution) {
1354 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1355 r1.tstamp = tstamp;
1356 r1.val = resolution;
1357 snd_timer_user_append_to_tqueue(tu, &r1);
1358 tu->last_resolution = resolution;
1359 append++;
1360 }
1361 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1362 goto __wake;
1363 if (ticks == 0)
1364 goto __wake;
1365 if (tu->qused > 0) {
1366 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1367 r = &tu->tqueue[prev];
1368 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1369 r->tstamp = tstamp;
1370 r->val += ticks;
1371 append++;
1372 goto __wake;
1373 }
1374 }
1375 r1.event = SNDRV_TIMER_EVENT_TICK;
1376 r1.tstamp = tstamp;
1377 r1.val = ticks;
1378 snd_timer_user_append_to_tqueue(tu, &r1);
1379 append++;
1380 __wake:
1381 spin_unlock(&tu->qlock);
1382 if (append == 0)
1383 return;
1384 kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1385 wake_up(&tu->qchange_sleep);
1386}
1387
1388static int realloc_user_queue(struct snd_timer_user *tu, int size)
1389{
1390 struct snd_timer_read *queue = NULL;
1391 struct snd_timer_tread *tqueue = NULL;
1392
1393 if (tu->tread) {
1394 tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL);
1395 if (!tqueue)
1396 return -ENOMEM;
1397 } else {
1398 queue = kcalloc(size, sizeof(*queue), GFP_KERNEL);
1399 if (!queue)
1400 return -ENOMEM;
1401 }
1402
1403 spin_lock_irq(&tu->qlock);
1404 kfree(tu->queue);
1405 kfree(tu->tqueue);
1406 tu->queue_size = size;
1407 tu->queue = queue;
1408 tu->tqueue = tqueue;
1409 tu->qhead = tu->qtail = tu->qused = 0;
1410 spin_unlock_irq(&tu->qlock);
1411
1412 return 0;
1413}
1414
1415static int snd_timer_user_open(struct inode *inode, struct file *file)
1416{
1417 struct snd_timer_user *tu;
1418 int err;
1419
1420 err = nonseekable_open(inode, file);
1421 if (err < 0)
1422 return err;
1423
1424 tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1425 if (tu == NULL)
1426 return -ENOMEM;
1427 spin_lock_init(&tu->qlock);
1428 init_waitqueue_head(&tu->qchange_sleep);
1429 mutex_init(&tu->ioctl_lock);
1430 tu->ticks = 1;
1431 if (realloc_user_queue(tu, 128) < 0) {
1432 kfree(tu);
1433 return -ENOMEM;
1434 }
1435 file->private_data = tu;
1436 return 0;
1437}
1438
1439static int snd_timer_user_release(struct inode *inode, struct file *file)
1440{
1441 struct snd_timer_user *tu;
1442
1443 if (file->private_data) {
1444 tu = file->private_data;
1445 file->private_data = NULL;
1446 mutex_lock(&tu->ioctl_lock);
1447 if (tu->timeri)
1448 snd_timer_close(tu->timeri);
1449 mutex_unlock(&tu->ioctl_lock);
1450 kfree(tu->queue);
1451 kfree(tu->tqueue);
1452 kfree(tu);
1453 }
1454 return 0;
1455}
1456
1457static void snd_timer_user_zero_id(struct snd_timer_id *id)
1458{
1459 id->dev_class = SNDRV_TIMER_CLASS_NONE;
1460 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1461 id->card = -1;
1462 id->device = -1;
1463 id->subdevice = -1;
1464}
1465
1466static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1467{
1468 id->dev_class = timer->tmr_class;
1469 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1470 id->card = timer->card ? timer->card->number : -1;
1471 id->device = timer->tmr_device;
1472 id->subdevice = timer->tmr_subdevice;
1473}
1474
1475static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1476{
1477 struct snd_timer_id id;
1478 struct snd_timer *timer;
1479 struct list_head *p;
1480
1481 if (copy_from_user(&id, _tid, sizeof(id)))
1482 return -EFAULT;
1483 mutex_lock(®ister_mutex);
1484 if (id.dev_class < 0) { /* first item */
1485 if (list_empty(&snd_timer_list))
1486 snd_timer_user_zero_id(&id);
1487 else {
1488 timer = list_entry(snd_timer_list.next,
1489 struct snd_timer, device_list);
1490 snd_timer_user_copy_id(&id, timer);
1491 }
1492 } else {
1493 switch (id.dev_class) {
1494 case SNDRV_TIMER_CLASS_GLOBAL:
1495 id.device = id.device < 0 ? 0 : id.device + 1;
1496 list_for_each(p, &snd_timer_list) {
1497 timer = list_entry(p, struct snd_timer, device_list);
1498 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1499 snd_timer_user_copy_id(&id, timer);
1500 break;
1501 }
1502 if (timer->tmr_device >= id.device) {
1503 snd_timer_user_copy_id(&id, timer);
1504 break;
1505 }
1506 }
1507 if (p == &snd_timer_list)
1508 snd_timer_user_zero_id(&id);
1509 break;
1510 case SNDRV_TIMER_CLASS_CARD:
1511 case SNDRV_TIMER_CLASS_PCM:
1512 if (id.card < 0) {
1513 id.card = 0;
1514 } else {
1515 if (id.device < 0) {
1516 id.device = 0;
1517 } else {
1518 if (id.subdevice < 0)
1519 id.subdevice = 0;
1520 else
1521 id.subdevice++;
1522 }
1523 }
1524 list_for_each(p, &snd_timer_list) {
1525 timer = list_entry(p, struct snd_timer, device_list);
1526 if (timer->tmr_class > id.dev_class) {
1527 snd_timer_user_copy_id(&id, timer);
1528 break;
1529 }
1530 if (timer->tmr_class < id.dev_class)
1531 continue;
1532 if (timer->card->number > id.card) {
1533 snd_timer_user_copy_id(&id, timer);
1534 break;
1535 }
1536 if (timer->card->number < id.card)
1537 continue;
1538 if (timer->tmr_device > id.device) {
1539 snd_timer_user_copy_id(&id, timer);
1540 break;
1541 }
1542 if (timer->tmr_device < id.device)
1543 continue;
1544 if (timer->tmr_subdevice > id.subdevice) {
1545 snd_timer_user_copy_id(&id, timer);
1546 break;
1547 }
1548 if (timer->tmr_subdevice < id.subdevice)
1549 continue;
1550 snd_timer_user_copy_id(&id, timer);
1551 break;
1552 }
1553 if (p == &snd_timer_list)
1554 snd_timer_user_zero_id(&id);
1555 break;
1556 default:
1557 snd_timer_user_zero_id(&id);
1558 }
1559 }
1560 mutex_unlock(®ister_mutex);
1561 if (copy_to_user(_tid, &id, sizeof(*_tid)))
1562 return -EFAULT;
1563 return 0;
1564}
1565
1566static int snd_timer_user_ginfo(struct file *file,
1567 struct snd_timer_ginfo __user *_ginfo)
1568{
1569 struct snd_timer_ginfo *ginfo;
1570 struct snd_timer_id tid;
1571 struct snd_timer *t;
1572 struct list_head *p;
1573 int err = 0;
1574
1575 ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1576 if (IS_ERR(ginfo))
1577 return PTR_ERR(ginfo);
1578
1579 tid = ginfo->tid;
1580 memset(ginfo, 0, sizeof(*ginfo));
1581 ginfo->tid = tid;
1582 mutex_lock(®ister_mutex);
1583 t = snd_timer_find(&tid);
1584 if (t != NULL) {
1585 ginfo->card = t->card ? t->card->number : -1;
1586 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1587 ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1588 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1589 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1590 ginfo->resolution = t->hw.resolution;
1591 if (t->hw.resolution_min > 0) {
1592 ginfo->resolution_min = t->hw.resolution_min;
1593 ginfo->resolution_max = t->hw.resolution_max;
1594 }
1595 list_for_each(p, &t->open_list_head) {
1596 ginfo->clients++;
1597 }
1598 } else {
1599 err = -ENODEV;
1600 }
1601 mutex_unlock(®ister_mutex);
1602 if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1603 err = -EFAULT;
1604 kfree(ginfo);
1605 return err;
1606}
1607
1608static int timer_set_gparams(struct snd_timer_gparams *gparams)
1609{
1610 struct snd_timer *t;
1611 int err;
1612
1613 mutex_lock(®ister_mutex);
1614 t = snd_timer_find(&gparams->tid);
1615 if (!t) {
1616 err = -ENODEV;
1617 goto _error;
1618 }
1619 if (!list_empty(&t->open_list_head)) {
1620 err = -EBUSY;
1621 goto _error;
1622 }
1623 if (!t->hw.set_period) {
1624 err = -ENOSYS;
1625 goto _error;
1626 }
1627 err = t->hw.set_period(t, gparams->period_num, gparams->period_den);
1628_error:
1629 mutex_unlock(®ister_mutex);
1630 return err;
1631}
1632
1633static int snd_timer_user_gparams(struct file *file,
1634 struct snd_timer_gparams __user *_gparams)
1635{
1636 struct snd_timer_gparams gparams;
1637
1638 if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1639 return -EFAULT;
1640 return timer_set_gparams(&gparams);
1641}
1642
1643static int snd_timer_user_gstatus(struct file *file,
1644 struct snd_timer_gstatus __user *_gstatus)
1645{
1646 struct snd_timer_gstatus gstatus;
1647 struct snd_timer_id tid;
1648 struct snd_timer *t;
1649 int err = 0;
1650
1651 if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1652 return -EFAULT;
1653 tid = gstatus.tid;
1654 memset(&gstatus, 0, sizeof(gstatus));
1655 gstatus.tid = tid;
1656 mutex_lock(®ister_mutex);
1657 t = snd_timer_find(&tid);
1658 if (t != NULL) {
1659 if (t->hw.c_resolution)
1660 gstatus.resolution = t->hw.c_resolution(t);
1661 else
1662 gstatus.resolution = t->hw.resolution;
1663 if (t->hw.precise_resolution) {
1664 t->hw.precise_resolution(t, &gstatus.resolution_num,
1665 &gstatus.resolution_den);
1666 } else {
1667 gstatus.resolution_num = gstatus.resolution;
1668 gstatus.resolution_den = 1000000000uL;
1669 }
1670 } else {
1671 err = -ENODEV;
1672 }
1673 mutex_unlock(®ister_mutex);
1674 if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1675 err = -EFAULT;
1676 return err;
1677}
1678
1679static int snd_timer_user_tselect(struct file *file,
1680 struct snd_timer_select __user *_tselect)
1681{
1682 struct snd_timer_user *tu;
1683 struct snd_timer_select tselect;
1684 char str[32];
1685 int err = 0;
1686
1687 tu = file->private_data;
1688 if (tu->timeri) {
1689 snd_timer_close(tu->timeri);
1690 tu->timeri = NULL;
1691 }
1692 if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1693 err = -EFAULT;
1694 goto __err;
1695 }
1696 sprintf(str, "application %i", current->pid);
1697 if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1698 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1699 err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1700 if (err < 0)
1701 goto __err;
1702
1703 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1704 tu->timeri->callback = tu->tread
1705 ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1706 tu->timeri->ccallback = snd_timer_user_ccallback;
1707 tu->timeri->callback_data = (void *)tu;
1708 tu->timeri->disconnect = snd_timer_user_disconnect;
1709
1710 __err:
1711 return err;
1712}
1713
1714static int snd_timer_user_info(struct file *file,
1715 struct snd_timer_info __user *_info)
1716{
1717 struct snd_timer_user *tu;
1718 struct snd_timer_info *info;
1719 struct snd_timer *t;
1720 int err = 0;
1721
1722 tu = file->private_data;
1723 if (!tu->timeri)
1724 return -EBADFD;
1725 t = tu->timeri->timer;
1726 if (!t)
1727 return -EBADFD;
1728
1729 info = kzalloc(sizeof(*info), GFP_KERNEL);
1730 if (! info)
1731 return -ENOMEM;
1732 info->card = t->card ? t->card->number : -1;
1733 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1734 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1735 strlcpy(info->id, t->id, sizeof(info->id));
1736 strlcpy(info->name, t->name, sizeof(info->name));
1737 info->resolution = t->hw.resolution;
1738 if (copy_to_user(_info, info, sizeof(*_info)))
1739 err = -EFAULT;
1740 kfree(info);
1741 return err;
1742}
1743
1744static int snd_timer_user_params(struct file *file,
1745 struct snd_timer_params __user *_params)
1746{
1747 struct snd_timer_user *tu;
1748 struct snd_timer_params params;
1749 struct snd_timer *t;
1750 int err;
1751
1752 tu = file->private_data;
1753 if (!tu->timeri)
1754 return -EBADFD;
1755 t = tu->timeri->timer;
1756 if (!t)
1757 return -EBADFD;
1758 if (copy_from_user(¶ms, _params, sizeof(params)))
1759 return -EFAULT;
1760 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1761 u64 resolution;
1762
1763 if (params.ticks < 1) {
1764 err = -EINVAL;
1765 goto _end;
1766 }
1767
1768 /* Don't allow resolution less than 1ms */
1769 resolution = snd_timer_resolution(tu->timeri);
1770 resolution *= params.ticks;
1771 if (resolution < 1000000) {
1772 err = -EINVAL;
1773 goto _end;
1774 }
1775 }
1776 if (params.queue_size > 0 &&
1777 (params.queue_size < 32 || params.queue_size > 1024)) {
1778 err = -EINVAL;
1779 goto _end;
1780 }
1781 if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1782 (1<<SNDRV_TIMER_EVENT_TICK)|
1783 (1<<SNDRV_TIMER_EVENT_START)|
1784 (1<<SNDRV_TIMER_EVENT_STOP)|
1785 (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1786 (1<<SNDRV_TIMER_EVENT_PAUSE)|
1787 (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1788 (1<<SNDRV_TIMER_EVENT_RESUME)|
1789 (1<<SNDRV_TIMER_EVENT_MSTART)|
1790 (1<<SNDRV_TIMER_EVENT_MSTOP)|
1791 (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1792 (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1793 (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1794 (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1795 err = -EINVAL;
1796 goto _end;
1797 }
1798 snd_timer_stop(tu->timeri);
1799 spin_lock_irq(&t->lock);
1800 tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1801 SNDRV_TIMER_IFLG_EXCLUSIVE|
1802 SNDRV_TIMER_IFLG_EARLY_EVENT);
1803 if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1804 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1805 if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1806 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1807 if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1808 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1809 spin_unlock_irq(&t->lock);
1810 if (params.queue_size > 0 &&
1811 (unsigned int)tu->queue_size != params.queue_size) {
1812 err = realloc_user_queue(tu, params.queue_size);
1813 if (err < 0)
1814 goto _end;
1815 }
1816 spin_lock_irq(&tu->qlock);
1817 tu->qhead = tu->qtail = tu->qused = 0;
1818 if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1819 if (tu->tread) {
1820 struct snd_timer_tread tread;
1821 memset(&tread, 0, sizeof(tread));
1822 tread.event = SNDRV_TIMER_EVENT_EARLY;
1823 tread.tstamp.tv_sec = 0;
1824 tread.tstamp.tv_nsec = 0;
1825 tread.val = 0;
1826 snd_timer_user_append_to_tqueue(tu, &tread);
1827 } else {
1828 struct snd_timer_read *r = &tu->queue[0];
1829 r->resolution = 0;
1830 r->ticks = 0;
1831 tu->qused++;
1832 tu->qtail++;
1833 }
1834 }
1835 tu->filter = params.filter;
1836 tu->ticks = params.ticks;
1837 spin_unlock_irq(&tu->qlock);
1838 err = 0;
1839 _end:
1840 if (copy_to_user(_params, ¶ms, sizeof(params)))
1841 return -EFAULT;
1842 return err;
1843}
1844
1845static int snd_timer_user_status(struct file *file,
1846 struct snd_timer_status __user *_status)
1847{
1848 struct snd_timer_user *tu;
1849 struct snd_timer_status status;
1850
1851 tu = file->private_data;
1852 if (!tu->timeri)
1853 return -EBADFD;
1854 memset(&status, 0, sizeof(status));
1855 status.tstamp = tu->tstamp;
1856 status.resolution = snd_timer_resolution(tu->timeri);
1857 status.lost = tu->timeri->lost;
1858 status.overrun = tu->overrun;
1859 spin_lock_irq(&tu->qlock);
1860 status.queue = tu->qused;
1861 spin_unlock_irq(&tu->qlock);
1862 if (copy_to_user(_status, &status, sizeof(status)))
1863 return -EFAULT;
1864 return 0;
1865}
1866
1867static int snd_timer_user_start(struct file *file)
1868{
1869 int err;
1870 struct snd_timer_user *tu;
1871
1872 tu = file->private_data;
1873 if (!tu->timeri)
1874 return -EBADFD;
1875 snd_timer_stop(tu->timeri);
1876 tu->timeri->lost = 0;
1877 tu->last_resolution = 0;
1878 return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1879}
1880
1881static int snd_timer_user_stop(struct file *file)
1882{
1883 int err;
1884 struct snd_timer_user *tu;
1885
1886 tu = file->private_data;
1887 if (!tu->timeri)
1888 return -EBADFD;
1889 return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1890}
1891
1892static int snd_timer_user_continue(struct file *file)
1893{
1894 int err;
1895 struct snd_timer_user *tu;
1896
1897 tu = file->private_data;
1898 if (!tu->timeri)
1899 return -EBADFD;
1900 /* start timer instead of continue if it's not used before */
1901 if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
1902 return snd_timer_user_start(file);
1903 tu->timeri->lost = 0;
1904 return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1905}
1906
1907static int snd_timer_user_pause(struct file *file)
1908{
1909 int err;
1910 struct snd_timer_user *tu;
1911
1912 tu = file->private_data;
1913 if (!tu->timeri)
1914 return -EBADFD;
1915 return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1916}
1917
1918enum {
1919 SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1920 SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1921 SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1922 SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1923};
1924
1925static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1926 unsigned long arg)
1927{
1928 struct snd_timer_user *tu;
1929 void __user *argp = (void __user *)arg;
1930 int __user *p = argp;
1931
1932 tu = file->private_data;
1933 switch (cmd) {
1934 case SNDRV_TIMER_IOCTL_PVERSION:
1935 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1936 case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1937 return snd_timer_user_next_device(argp);
1938 case SNDRV_TIMER_IOCTL_TREAD:
1939 {
1940 int xarg, old_tread;
1941
1942 if (tu->timeri) /* too late */
1943 return -EBUSY;
1944 if (get_user(xarg, p))
1945 return -EFAULT;
1946 old_tread = tu->tread;
1947 tu->tread = xarg ? 1 : 0;
1948 if (tu->tread != old_tread &&
1949 realloc_user_queue(tu, tu->queue_size) < 0) {
1950 tu->tread = old_tread;
1951 return -ENOMEM;
1952 }
1953 return 0;
1954 }
1955 case SNDRV_TIMER_IOCTL_GINFO:
1956 return snd_timer_user_ginfo(file, argp);
1957 case SNDRV_TIMER_IOCTL_GPARAMS:
1958 return snd_timer_user_gparams(file, argp);
1959 case SNDRV_TIMER_IOCTL_GSTATUS:
1960 return snd_timer_user_gstatus(file, argp);
1961 case SNDRV_TIMER_IOCTL_SELECT:
1962 return snd_timer_user_tselect(file, argp);
1963 case SNDRV_TIMER_IOCTL_INFO:
1964 return snd_timer_user_info(file, argp);
1965 case SNDRV_TIMER_IOCTL_PARAMS:
1966 return snd_timer_user_params(file, argp);
1967 case SNDRV_TIMER_IOCTL_STATUS:
1968 return snd_timer_user_status(file, argp);
1969 case SNDRV_TIMER_IOCTL_START:
1970 case SNDRV_TIMER_IOCTL_START_OLD:
1971 return snd_timer_user_start(file);
1972 case SNDRV_TIMER_IOCTL_STOP:
1973 case SNDRV_TIMER_IOCTL_STOP_OLD:
1974 return snd_timer_user_stop(file);
1975 case SNDRV_TIMER_IOCTL_CONTINUE:
1976 case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1977 return snd_timer_user_continue(file);
1978 case SNDRV_TIMER_IOCTL_PAUSE:
1979 case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1980 return snd_timer_user_pause(file);
1981 }
1982 return -ENOTTY;
1983}
1984
1985static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1986 unsigned long arg)
1987{
1988 struct snd_timer_user *tu = file->private_data;
1989 long ret;
1990
1991 mutex_lock(&tu->ioctl_lock);
1992 ret = __snd_timer_user_ioctl(file, cmd, arg);
1993 mutex_unlock(&tu->ioctl_lock);
1994 return ret;
1995}
1996
1997static int snd_timer_user_fasync(int fd, struct file * file, int on)
1998{
1999 struct snd_timer_user *tu;
2000
2001 tu = file->private_data;
2002 return fasync_helper(fd, file, on, &tu->fasync);
2003}
2004
2005static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2006 size_t count, loff_t *offset)
2007{
2008 struct snd_timer_user *tu;
2009 long result = 0, unit;
2010 int qhead;
2011 int err = 0;
2012
2013 tu = file->private_data;
2014 unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
2015 mutex_lock(&tu->ioctl_lock);
2016 spin_lock_irq(&tu->qlock);
2017 while ((long)count - result >= unit) {
2018 while (!tu->qused) {
2019 wait_queue_entry_t wait;
2020
2021 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2022 err = -EAGAIN;
2023 goto _error;
2024 }
2025
2026 set_current_state(TASK_INTERRUPTIBLE);
2027 init_waitqueue_entry(&wait, current);
2028 add_wait_queue(&tu->qchange_sleep, &wait);
2029
2030 spin_unlock_irq(&tu->qlock);
2031 mutex_unlock(&tu->ioctl_lock);
2032 schedule();
2033 mutex_lock(&tu->ioctl_lock);
2034 spin_lock_irq(&tu->qlock);
2035
2036 remove_wait_queue(&tu->qchange_sleep, &wait);
2037
2038 if (tu->disconnected) {
2039 err = -ENODEV;
2040 goto _error;
2041 }
2042 if (signal_pending(current)) {
2043 err = -ERESTARTSYS;
2044 goto _error;
2045 }
2046 }
2047
2048 qhead = tu->qhead++;
2049 tu->qhead %= tu->queue_size;
2050 tu->qused--;
2051 spin_unlock_irq(&tu->qlock);
2052
2053 if (tu->tread) {
2054 if (copy_to_user(buffer, &tu->tqueue[qhead],
2055 sizeof(struct snd_timer_tread)))
2056 err = -EFAULT;
2057 } else {
2058 if (copy_to_user(buffer, &tu->queue[qhead],
2059 sizeof(struct snd_timer_read)))
2060 err = -EFAULT;
2061 }
2062
2063 spin_lock_irq(&tu->qlock);
2064 if (err < 0)
2065 goto _error;
2066 result += unit;
2067 buffer += unit;
2068 }
2069 _error:
2070 spin_unlock_irq(&tu->qlock);
2071 mutex_unlock(&tu->ioctl_lock);
2072 return result > 0 ? result : err;
2073}
2074
2075static __poll_t snd_timer_user_poll(struct file *file, poll_table * wait)
2076{
2077 __poll_t mask;
2078 struct snd_timer_user *tu;
2079
2080 tu = file->private_data;
2081
2082 poll_wait(file, &tu->qchange_sleep, wait);
2083
2084 mask = 0;
2085 spin_lock_irq(&tu->qlock);
2086 if (tu->qused)
2087 mask |= EPOLLIN | EPOLLRDNORM;
2088 if (tu->disconnected)
2089 mask |= EPOLLERR;
2090 spin_unlock_irq(&tu->qlock);
2091
2092 return mask;
2093}
2094
2095#ifdef CONFIG_COMPAT
2096#include "timer_compat.c"
2097#else
2098#define snd_timer_user_ioctl_compat NULL
2099#endif
2100
2101static const struct file_operations snd_timer_f_ops =
2102{
2103 .owner = THIS_MODULE,
2104 .read = snd_timer_user_read,
2105 .open = snd_timer_user_open,
2106 .release = snd_timer_user_release,
2107 .llseek = no_llseek,
2108 .poll = snd_timer_user_poll,
2109 .unlocked_ioctl = snd_timer_user_ioctl,
2110 .compat_ioctl = snd_timer_user_ioctl_compat,
2111 .fasync = snd_timer_user_fasync,
2112};
2113
2114/* unregister the system timer */
2115static void snd_timer_free_all(void)
2116{
2117 struct snd_timer *timer, *n;
2118
2119 list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2120 snd_timer_free(timer);
2121}
2122
2123static struct device timer_dev;
2124
2125/*
2126 * ENTRY functions
2127 */
2128
2129static int __init alsa_timer_init(void)
2130{
2131 int err;
2132
2133 snd_device_initialize(&timer_dev, NULL);
2134 dev_set_name(&timer_dev, "timer");
2135
2136#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2137 snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2138 "system timer");
2139#endif
2140
2141 err = snd_timer_register_system();
2142 if (err < 0) {
2143 pr_err("ALSA: unable to register system timer (%i)\n", err);
2144 goto put_timer;
2145 }
2146
2147 err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2148 &snd_timer_f_ops, NULL, &timer_dev);
2149 if (err < 0) {
2150 pr_err("ALSA: unable to register timer device (%i)\n", err);
2151 snd_timer_free_all();
2152 goto put_timer;
2153 }
2154
2155 snd_timer_proc_init();
2156 return 0;
2157
2158put_timer:
2159 put_device(&timer_dev);
2160 return err;
2161}
2162
2163static void __exit alsa_timer_exit(void)
2164{
2165 snd_unregister_device(&timer_dev);
2166 snd_timer_free_all();
2167 put_device(&timer_dev);
2168 snd_timer_proc_done();
2169#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2170 snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2171#endif
2172}
2173
2174module_init(alsa_timer_init)
2175module_exit(alsa_timer_exit)