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