xref: /openbmc/linux/sound/core/timer.c (revision d5cb9783536a41df9f9cba5b0a1d78047ed787f7)
1 /*
2  *  Timers abstract layer
3  *  Copyright (c) by Jaroslav Kysela <perex@suse.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 <sound/driver.h>
23 #include <linux/delay.h>
24 #include <linux/init.h>
25 #include <linux/smp_lock.h>
26 #include <linux/slab.h>
27 #include <linux/time.h>
28 #include <linux/moduleparam.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 #ifdef CONFIG_KERNELD
38 #include <linux/kerneld.h>
39 #endif
40 
41 #if defined(CONFIG_SND_HPET) || defined(CONFIG_SND_HPET_MODULE)
42 #define DEFAULT_TIMER_LIMIT 3
43 #elif defined(CONFIG_SND_RTCTIMER) || defined(CONFIG_SND_RTCTIMER_MODULE)
44 #define DEFAULT_TIMER_LIMIT 2
45 #else
46 #define DEFAULT_TIMER_LIMIT 1
47 #endif
48 
49 static int timer_limit = DEFAULT_TIMER_LIMIT;
50 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>, Takashi Iwai <tiwai@suse.de>");
51 MODULE_DESCRIPTION("ALSA timer interface");
52 MODULE_LICENSE("GPL");
53 module_param(timer_limit, int, 0444);
54 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
55 
56 typedef struct {
57 	snd_timer_instance_t *timeri;
58 	int tread;			/* enhanced read with timestamps and events */
59 	unsigned long ticks;
60 	unsigned long overrun;
61 	int qhead;
62 	int qtail;
63 	int qused;
64 	int queue_size;
65 	snd_timer_read_t *queue;
66 	snd_timer_tread_t *tqueue;
67 	spinlock_t qlock;
68 	unsigned long last_resolution;
69 	unsigned int filter;
70 	struct timespec tstamp;		/* trigger tstamp */
71 	wait_queue_head_t qchange_sleep;
72 	struct fasync_struct *fasync;
73 	struct semaphore tread_sem;
74 } snd_timer_user_t;
75 
76 /* list of timers */
77 static LIST_HEAD(snd_timer_list);
78 
79 /* list of slave instances */
80 static LIST_HEAD(snd_timer_slave_list);
81 
82 /* lock for slave active lists */
83 static DEFINE_SPINLOCK(slave_active_lock);
84 
85 static DECLARE_MUTEX(register_mutex);
86 
87 static int snd_timer_free(snd_timer_t *timer);
88 static int snd_timer_dev_free(snd_device_t *device);
89 static int snd_timer_dev_register(snd_device_t *device);
90 static int snd_timer_dev_unregister(snd_device_t *device);
91 
92 static void snd_timer_reschedule(snd_timer_t * timer, unsigned long ticks_left);
93 
94 /*
95  * create a timer instance with the given owner string.
96  * when timer is not NULL, increments the module counter
97  */
98 static snd_timer_instance_t *snd_timer_instance_new(char *owner, snd_timer_t *timer)
99 {
100 	snd_timer_instance_t *timeri;
101 	timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
102 	if (timeri == NULL)
103 		return NULL;
104 	timeri->owner = kstrdup(owner, GFP_KERNEL);
105 	if (! timeri->owner) {
106 		kfree(timeri);
107 		return NULL;
108 	}
109 	INIT_LIST_HEAD(&timeri->open_list);
110 	INIT_LIST_HEAD(&timeri->active_list);
111 	INIT_LIST_HEAD(&timeri->ack_list);
112 	INIT_LIST_HEAD(&timeri->slave_list_head);
113 	INIT_LIST_HEAD(&timeri->slave_active_head);
114 
115 	timeri->timer = timer;
116 	if (timer && timer->card && !try_module_get(timer->card->module)) {
117 		kfree(timeri->owner);
118 		kfree(timeri);
119 		return NULL;
120 	}
121 
122 	return timeri;
123 }
124 
125 /*
126  * find a timer instance from the given timer id
127  */
128 static snd_timer_t *snd_timer_find(snd_timer_id_t *tid)
129 {
130 	snd_timer_t *timer = NULL;
131 	struct list_head *p;
132 
133 	list_for_each(p, &snd_timer_list) {
134 		timer = (snd_timer_t *)list_entry(p, snd_timer_t, device_list);
135 
136 		if (timer->tmr_class != tid->dev_class)
137 			continue;
138 		if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
139 		     timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
140 		    (timer->card == NULL ||
141 		     timer->card->number != tid->card))
142 			continue;
143 		if (timer->tmr_device != tid->device)
144 			continue;
145 		if (timer->tmr_subdevice != tid->subdevice)
146 			continue;
147 		return timer;
148 	}
149 	return NULL;
150 }
151 
152 #ifdef CONFIG_KMOD
153 
154 static void snd_timer_request(snd_timer_id_t *tid)
155 {
156 	if (! current->fs->root)
157 		return;
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  */
181 static void snd_timer_check_slave(snd_timer_instance_t *slave)
182 {
183 	snd_timer_t *timer;
184 	snd_timer_instance_t *master;
185 	struct list_head *p, *q;
186 
187 	/* FIXME: it's really dumb to look up all entries.. */
188 	list_for_each(p, &snd_timer_list) {
189 		timer = (snd_timer_t *)list_entry(p, snd_timer_t, device_list);
190 		list_for_each(q, &timer->open_list_head) {
191 			master = (snd_timer_instance_t *)list_entry(q, snd_timer_instance_t, open_list);
192 			if (slave->slave_class == master->slave_class &&
193 			    slave->slave_id == master->slave_id) {
194 				list_del(&slave->open_list);
195 				list_add_tail(&slave->open_list, &master->slave_list_head);
196 				spin_lock_irq(&slave_active_lock);
197 				slave->master = master;
198 				slave->timer = master->timer;
199 				spin_unlock_irq(&slave_active_lock);
200 				return;
201 			}
202 		}
203 	}
204 }
205 
206 /*
207  * look for slave instances matching with the slave id of the given master.
208  * when found, relink the open_link of slaves.
209  *
210  * call this with register_mutex down.
211  */
212 static void snd_timer_check_master(snd_timer_instance_t *master)
213 {
214 	snd_timer_instance_t *slave;
215 	struct list_head *p, *n;
216 
217 	/* check all pending slaves */
218 	list_for_each_safe(p, n, &snd_timer_slave_list) {
219 		slave = (snd_timer_instance_t *)list_entry(p, snd_timer_instance_t, open_list);
220 		if (slave->slave_class == master->slave_class &&
221 		    slave->slave_id == master->slave_id) {
222 			list_del(p);
223 			list_add_tail(p, &master->slave_list_head);
224 			spin_lock_irq(&slave_active_lock);
225 			slave->master = master;
226 			slave->timer = master->timer;
227 			if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
228 				list_add_tail(&slave->active_list, &master->slave_active_head);
229 			spin_unlock_irq(&slave_active_lock);
230 		}
231 	}
232 }
233 
234 /*
235  * open a timer instance
236  * when opening a master, the slave id must be here given.
237  */
238 int snd_timer_open(snd_timer_instance_t **ti,
239 		   char *owner, snd_timer_id_t *tid,
240 		   unsigned int slave_id)
241 {
242 	snd_timer_t *timer;
243 	snd_timer_instance_t *timeri = NULL;
244 
245 	if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
246 		/* open a slave instance */
247 		if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
248 		    tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
249 			snd_printd("invalid slave class %i\n", tid->dev_sclass);
250 			return -EINVAL;
251 		}
252 		down(&register_mutex);
253 		timeri = snd_timer_instance_new(owner, NULL);
254 		timeri->slave_class = tid->dev_sclass;
255 		timeri->slave_id = tid->device;
256 		timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
257 		list_add_tail(&timeri->open_list, &snd_timer_slave_list);
258 		snd_timer_check_slave(timeri);
259 		up(&register_mutex);
260 		*ti = timeri;
261 		return 0;
262 	}
263 
264 	/* open a master instance */
265 	down(&register_mutex);
266 	timer = snd_timer_find(tid);
267 #ifdef CONFIG_KMOD
268 	if (timer == NULL) {
269 		up(&register_mutex);
270 		snd_timer_request(tid);
271 		down(&register_mutex);
272 		timer = snd_timer_find(tid);
273 	}
274 #endif
275 	if (timer) {
276 		if (!list_empty(&timer->open_list_head)) {
277 			timeri = (snd_timer_instance_t *)list_entry(timer->open_list_head.next, snd_timer_instance_t, open_list);
278 			if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
279 				up(&register_mutex);
280 				return -EBUSY;
281 			}
282 		}
283 		timeri = snd_timer_instance_new(owner, timer);
284 		if (timeri) {
285 			timeri->slave_class = tid->dev_sclass;
286 			timeri->slave_id = slave_id;
287 			if (list_empty(&timer->open_list_head) && timer->hw.open)
288 				timer->hw.open(timer);
289 			list_add_tail(&timeri->open_list, &timer->open_list_head);
290 			snd_timer_check_master(timeri);
291 		}
292 	} else {
293 		up(&register_mutex);
294 		return -ENODEV;
295 	}
296 	up(&register_mutex);
297 	*ti = timeri;
298 	return 0;
299 }
300 
301 static int _snd_timer_stop(snd_timer_instance_t * timeri, int keep_flag, enum sndrv_timer_event event);
302 
303 /*
304  * close a timer instance
305  */
306 int snd_timer_close(snd_timer_instance_t * timeri)
307 {
308 	snd_timer_t *timer = NULL;
309 	struct list_head *p, *n;
310 	snd_timer_instance_t *slave;
311 
312 	snd_assert(timeri != NULL, return -ENXIO);
313 
314 	/* force to stop the timer */
315 	snd_timer_stop(timeri);
316 
317 	if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
318 		/* wait, until the active callback is finished */
319 		spin_lock_irq(&slave_active_lock);
320 		while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
321 			spin_unlock_irq(&slave_active_lock);
322 			udelay(10);
323 			spin_lock_irq(&slave_active_lock);
324 		}
325 		spin_unlock_irq(&slave_active_lock);
326 		down(&register_mutex);
327 		list_del(&timeri->open_list);
328 		up(&register_mutex);
329 	} else {
330 		timer = timeri->timer;
331 		/* wait, until the active callback is finished */
332 		spin_lock_irq(&timer->lock);
333 		while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
334 			spin_unlock_irq(&timer->lock);
335 			udelay(10);
336 			spin_lock_irq(&timer->lock);
337 		}
338 		spin_unlock_irq(&timer->lock);
339 		down(&register_mutex);
340 		list_del(&timeri->open_list);
341 		if (timer && list_empty(&timer->open_list_head) && timer->hw.close)
342 			timer->hw.close(timer);
343 		/* remove slave links */
344 		list_for_each_safe(p, n, &timeri->slave_list_head) {
345 			slave = (snd_timer_instance_t *)list_entry(p, snd_timer_instance_t, open_list);
346 			spin_lock_irq(&slave_active_lock);
347 			_snd_timer_stop(slave, 1, SNDRV_TIMER_EVENT_RESOLUTION);
348 			list_del(p);
349 			list_add_tail(p, &snd_timer_slave_list);
350 			slave->master = NULL;
351 			slave->timer = NULL;
352 			spin_unlock_irq(&slave_active_lock);
353 		}
354 		up(&register_mutex);
355 	}
356 	if (timeri->private_free)
357 		timeri->private_free(timeri);
358 	kfree(timeri->owner);
359 	kfree(timeri);
360 	if (timer && timer->card)
361 		module_put(timer->card->module);
362 	return 0;
363 }
364 
365 unsigned long snd_timer_resolution(snd_timer_instance_t * timeri)
366 {
367 	snd_timer_t * timer;
368 
369 	if (timeri == NULL)
370 		return 0;
371 	if ((timer = timeri->timer) != NULL) {
372 		if (timer->hw.c_resolution)
373 			return timer->hw.c_resolution(timer);
374 		return timer->hw.resolution;
375 	}
376 	return 0;
377 }
378 
379 static void snd_timer_notify1(snd_timer_instance_t *ti, enum sndrv_timer_event event)
380 {
381 	snd_timer_t *timer;
382 	unsigned long flags;
383 	unsigned long resolution = 0;
384 	snd_timer_instance_t *ts;
385 	struct list_head *n;
386 	struct timespec tstamp;
387 
388 	snd_timestamp_now(&tstamp, 1);
389 	snd_assert(event >= SNDRV_TIMER_EVENT_START && event <= SNDRV_TIMER_EVENT_PAUSE, return);
390 	if (event == SNDRV_TIMER_EVENT_START || event == SNDRV_TIMER_EVENT_CONTINUE)
391 		resolution = snd_timer_resolution(ti);
392 	if (ti->ccallback)
393 		ti->ccallback(ti, SNDRV_TIMER_EVENT_START, &tstamp, resolution);
394 	if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
395 		return;
396 	timer = ti->timer;
397 	if (timer == NULL)
398 		return;
399 	if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
400 		return;
401 	spin_lock_irqsave(&timer->lock, flags);
402 	list_for_each(n, &ti->slave_active_head) {
403 		ts = (snd_timer_instance_t *)list_entry(n, snd_timer_instance_t, active_list);
404 		if (ts->ccallback)
405 			ts->ccallback(ti, event + 100, &tstamp, resolution);
406 	}
407 	spin_unlock_irqrestore(&timer->lock, flags);
408 }
409 
410 static int snd_timer_start1(snd_timer_t *timer, snd_timer_instance_t *timeri, unsigned long sticks)
411 {
412 	list_del(&timeri->active_list);
413 	list_add_tail(&timeri->active_list, &timer->active_list_head);
414 	if (timer->running) {
415 		if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
416 			goto __start_now;
417 		timer->flags |= SNDRV_TIMER_FLG_RESCHED;
418 		timeri->flags |= SNDRV_TIMER_IFLG_START;
419 		return 1;	/* delayed start */
420 	} else {
421 		timer->sticks = sticks;
422 		timer->hw.start(timer);
423 	      __start_now:
424 		timer->running++;
425 		timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
426 		return 0;
427 	}
428 }
429 
430 static int snd_timer_start_slave(snd_timer_instance_t *timeri)
431 {
432 	unsigned long flags;
433 
434 	spin_lock_irqsave(&slave_active_lock, flags);
435 	timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
436 	if (timeri->master)
437 		list_add_tail(&timeri->active_list, &timeri->master->slave_active_head);
438 	spin_unlock_irqrestore(&slave_active_lock, flags);
439 	return 1; /* delayed start */
440 }
441 
442 /*
443  *  start the timer instance
444  */
445 int snd_timer_start(snd_timer_instance_t * timeri, unsigned int ticks)
446 {
447 	snd_timer_t *timer;
448 	int result = -EINVAL;
449 	unsigned long flags;
450 
451 	if (timeri == NULL || ticks < 1)
452 		return -EINVAL;
453 	if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
454 		result = snd_timer_start_slave(timeri);
455 		snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
456 		return result;
457 	}
458 	timer = timeri->timer;
459 	if (timer == NULL)
460 		return -EINVAL;
461 	spin_lock_irqsave(&timer->lock, flags);
462 	timeri->ticks = timeri->cticks = ticks;
463 	timeri->pticks = 0;
464 	result = snd_timer_start1(timer, timeri, ticks);
465 	spin_unlock_irqrestore(&timer->lock, flags);
466 	snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
467 	return result;
468 }
469 
470 static int _snd_timer_stop(snd_timer_instance_t * timeri, int keep_flag, enum sndrv_timer_event event)
471 {
472 	snd_timer_t *timer;
473 	unsigned long flags;
474 
475 	snd_assert(timeri != NULL, return -ENXIO);
476 
477 	if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
478 		if (!keep_flag) {
479 			spin_lock_irqsave(&slave_active_lock, flags);
480 			timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
481 			spin_unlock_irqrestore(&slave_active_lock, flags);
482 		}
483 		goto __end;
484 	}
485 	timer = timeri->timer;
486 	if (!timer)
487 		return -EINVAL;
488 	spin_lock_irqsave(&timer->lock, flags);
489 	list_del_init(&timeri->ack_list);
490 	list_del_init(&timeri->active_list);
491 	if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
492 	    !(--timer->running)) {
493 		timer->hw.stop(timer);
494 		if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
495 			timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
496 			snd_timer_reschedule(timer, 0);
497 			if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
498 				timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
499 				timer->hw.start(timer);
500 			}
501 		}
502 	}
503 	if (!keep_flag)
504 		timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING|SNDRV_TIMER_IFLG_START);
505 	spin_unlock_irqrestore(&timer->lock, flags);
506       __end:
507 	if (event != SNDRV_TIMER_EVENT_RESOLUTION)
508 		snd_timer_notify1(timeri, event);
509 	return 0;
510 }
511 
512 /*
513  * stop the timer instance.
514  *
515  * do not call this from the timer callback!
516  */
517 int snd_timer_stop(snd_timer_instance_t * timeri)
518 {
519 	snd_timer_t *timer;
520 	unsigned long flags;
521 	int err;
522 
523 	err = _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_STOP);
524 	if (err < 0)
525 		return err;
526 	timer = timeri->timer;
527 	spin_lock_irqsave(&timer->lock, flags);
528 	timeri->cticks = timeri->ticks;
529 	timeri->pticks = 0;
530 	spin_unlock_irqrestore(&timer->lock, flags);
531 	return 0;
532 }
533 
534 /*
535  * start again..  the tick is kept.
536  */
537 int snd_timer_continue(snd_timer_instance_t * timeri)
538 {
539 	snd_timer_t *timer;
540 	int result = -EINVAL;
541 	unsigned long flags;
542 
543 	if (timeri == NULL)
544 		return result;
545 	if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
546 		return snd_timer_start_slave(timeri);
547 	timer = timeri->timer;
548 	if (! timer)
549 		return -EINVAL;
550 	spin_lock_irqsave(&timer->lock, flags);
551 	if (!timeri->cticks)
552 		timeri->cticks = 1;
553 	timeri->pticks = 0;
554 	result = snd_timer_start1(timer, timeri, timer->sticks);
555 	spin_unlock_irqrestore(&timer->lock, flags);
556 	snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_CONTINUE);
557 	return result;
558 }
559 
560 /*
561  * pause.. remember the ticks left
562  */
563 int snd_timer_pause(snd_timer_instance_t * timeri)
564 {
565 	return _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_PAUSE);
566 }
567 
568 /*
569  * reschedule the timer
570  *
571  * start pending instances and check the scheduling ticks.
572  * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
573  */
574 static void snd_timer_reschedule(snd_timer_t * timer, unsigned long ticks_left)
575 {
576 	snd_timer_instance_t *ti;
577 	unsigned long ticks = ~0UL;
578 	struct list_head *p;
579 
580 	list_for_each(p, &timer->active_list_head) {
581 		ti = (snd_timer_instance_t *)list_entry(p, snd_timer_instance_t, active_list);
582 		if (ti->flags & SNDRV_TIMER_IFLG_START) {
583 			ti->flags &= ~SNDRV_TIMER_IFLG_START;
584 			ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
585 			timer->running++;
586 		}
587 		if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
588 			if (ticks > ti->cticks)
589 				ticks = ti->cticks;
590 		}
591 	}
592 	if (ticks == ~0UL) {
593 		timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
594 		return;
595 	}
596 	if (ticks > timer->hw.ticks)
597 		ticks = timer->hw.ticks;
598 	if (ticks_left != ticks)
599 		timer->flags |= SNDRV_TIMER_FLG_CHANGE;
600 	timer->sticks = ticks;
601 }
602 
603 /*
604  * timer tasklet
605  *
606  */
607 static void snd_timer_tasklet(unsigned long arg)
608 {
609 	snd_timer_t *timer = (snd_timer_t *) arg;
610 	snd_timer_instance_t *ti;
611 	struct list_head *p;
612 	unsigned long resolution, ticks;
613 
614 	spin_lock(&timer->lock);
615 	/* now process all callbacks */
616 	while (!list_empty(&timer->sack_list_head)) {
617 		p = timer->sack_list_head.next;		/* get first item */
618 		ti = (snd_timer_instance_t *)list_entry(p, snd_timer_instance_t, ack_list);
619 
620 		/* remove from ack_list and make empty */
621 		list_del_init(p);
622 
623 		ticks = ti->pticks;
624 		ti->pticks = 0;
625 		resolution = ti->resolution;
626 
627 		ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
628 		spin_unlock(&timer->lock);
629 		if (ti->callback)
630 			ti->callback(ti, resolution, ticks);
631 		spin_lock(&timer->lock);
632 		ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
633 	}
634 	spin_unlock(&timer->lock);
635 }
636 
637 /*
638  * timer interrupt
639  *
640  * ticks_left is usually equal to timer->sticks.
641  *
642  */
643 void snd_timer_interrupt(snd_timer_t * timer, unsigned long ticks_left)
644 {
645 	snd_timer_instance_t *ti, *ts;
646 	unsigned long resolution, ticks;
647 	struct list_head *p, *q, *n;
648 	int use_tasklet = 0;
649 
650 	if (timer == NULL)
651 		return;
652 
653 	spin_lock(&timer->lock);
654 
655 	/* remember the current resolution */
656 	if (timer->hw.c_resolution)
657 		resolution = timer->hw.c_resolution(timer);
658 	else
659 		resolution = timer->hw.resolution;
660 
661 	/* loop for all active instances
662 	 * here we cannot use list_for_each because the active_list of a processed
663 	 * instance is relinked to done_list_head before callback is called.
664 	 */
665 	list_for_each_safe(p, n, &timer->active_list_head) {
666 		ti = (snd_timer_instance_t *)list_entry(p, snd_timer_instance_t, active_list);
667 		if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
668 			continue;
669 		ti->pticks += ticks_left;
670 		ti->resolution = resolution;
671 		if (ti->cticks < ticks_left)
672 			ti->cticks = 0;
673 		else
674 			ti->cticks -= ticks_left;
675 		if (ti->cticks) /* not expired */
676 			continue;
677 		if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
678 			ti->cticks = ti->ticks;
679 		} else {
680 			ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
681 			if (--timer->running)
682 				list_del(p);
683 		}
684 		if (list_empty(&ti->ack_list)) {
685 			if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
686 			    (ti->flags & SNDRV_TIMER_IFLG_FAST)) {
687 				list_add_tail(&ti->ack_list, &timer->ack_list_head);
688 			} else {
689 				list_add_tail(&ti->ack_list, &timer->sack_list_head);
690 			}
691 		}
692 		list_for_each(q, &ti->slave_active_head) {
693 			ts = (snd_timer_instance_t *)list_entry(q, snd_timer_instance_t, active_list);
694 			ts->pticks = ti->pticks;
695 			ts->resolution = resolution;
696 			if (list_empty(&ts->ack_list)) {
697 				if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
698 				    (ti->flags & SNDRV_TIMER_IFLG_FAST)) {
699 					list_add_tail(&ts->ack_list, &timer->ack_list_head);
700 				} else {
701 					list_add_tail(&ts->ack_list, &timer->sack_list_head);
702 				}
703 			}
704 		}
705 	}
706 	if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
707 		snd_timer_reschedule(timer, ticks_left);
708 	if (timer->running) {
709 		if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
710 			timer->hw.stop(timer);
711 			timer->flags |= SNDRV_TIMER_FLG_CHANGE;
712 		}
713 		if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
714 		    (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
715 			/* restart timer */
716 			timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
717 			timer->hw.start(timer);
718 		}
719 	} else {
720 		timer->hw.stop(timer);
721 	}
722 
723 	/* now process all fast callbacks */
724 	while (!list_empty(&timer->ack_list_head)) {
725 		p = timer->ack_list_head.next;		/* get first item */
726 		ti = (snd_timer_instance_t *)list_entry(p, snd_timer_instance_t, ack_list);
727 
728 		/* remove from ack_list and make empty */
729 		list_del_init(p);
730 
731 		ticks = ti->pticks;
732 		ti->pticks = 0;
733 
734 		ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
735 		spin_unlock(&timer->lock);
736 		if (ti->callback)
737 			ti->callback(ti, resolution, ticks);
738 		spin_lock(&timer->lock);
739 		ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
740 	}
741 
742 	/* do we have any slow callbacks? */
743 	use_tasklet = !list_empty(&timer->sack_list_head);
744 	spin_unlock(&timer->lock);
745 
746 	if (use_tasklet)
747 		tasklet_hi_schedule(&timer->task_queue);
748 }
749 
750 /*
751 
752  */
753 
754 int snd_timer_new(snd_card_t *card, char *id, snd_timer_id_t *tid, snd_timer_t ** rtimer)
755 {
756 	snd_timer_t *timer;
757 	int err;
758 	static snd_device_ops_t ops = {
759 		.dev_free = snd_timer_dev_free,
760 		.dev_register = snd_timer_dev_register,
761 		.dev_unregister = snd_timer_dev_unregister
762 	};
763 
764 	snd_assert(tid != NULL, return -EINVAL);
765 	snd_assert(rtimer != NULL, return -EINVAL);
766 	*rtimer = NULL;
767 	timer = kzalloc(sizeof(*timer), GFP_KERNEL);
768 	if (timer == NULL)
769 		return -ENOMEM;
770 	timer->tmr_class = tid->dev_class;
771 	timer->card = card;
772 	timer->tmr_device = tid->device;
773 	timer->tmr_subdevice = tid->subdevice;
774 	if (id)
775 		strlcpy(timer->id, id, sizeof(timer->id));
776 	INIT_LIST_HEAD(&timer->device_list);
777 	INIT_LIST_HEAD(&timer->open_list_head);
778 	INIT_LIST_HEAD(&timer->active_list_head);
779 	INIT_LIST_HEAD(&timer->ack_list_head);
780 	INIT_LIST_HEAD(&timer->sack_list_head);
781 	spin_lock_init(&timer->lock);
782 	tasklet_init(&timer->task_queue, snd_timer_tasklet, (unsigned long)timer);
783 	if (card != NULL) {
784 		if ((err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops)) < 0) {
785 			snd_timer_free(timer);
786 			return err;
787 		}
788 	}
789 	*rtimer = timer;
790 	return 0;
791 }
792 
793 static int snd_timer_free(snd_timer_t *timer)
794 {
795 	snd_assert(timer != NULL, return -ENXIO);
796 	if (timer->private_free)
797 		timer->private_free(timer);
798 	kfree(timer);
799 	return 0;
800 }
801 
802 static int snd_timer_dev_free(snd_device_t *device)
803 {
804 	snd_timer_t *timer = device->device_data;
805 	return snd_timer_free(timer);
806 }
807 
808 static int snd_timer_dev_register(snd_device_t *dev)
809 {
810 	snd_timer_t *timer = dev->device_data;
811 	snd_timer_t *timer1;
812 	struct list_head *p;
813 
814 	snd_assert(timer != NULL && timer->hw.start != NULL && timer->hw.stop != NULL, return -ENXIO);
815 	if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
816 	    !timer->hw.resolution && timer->hw.c_resolution == NULL)
817 	    	return -EINVAL;
818 
819 	down(&register_mutex);
820 	list_for_each(p, &snd_timer_list) {
821 		timer1 = (snd_timer_t *)list_entry(p, snd_timer_t, device_list);
822 		if (timer1->tmr_class > timer->tmr_class)
823 			break;
824 		if (timer1->tmr_class < timer->tmr_class)
825 			continue;
826 		if (timer1->card && timer->card) {
827 			if (timer1->card->number > timer->card->number)
828 				break;
829 			if (timer1->card->number < timer->card->number)
830 				continue;
831 		}
832 		if (timer1->tmr_device > timer->tmr_device)
833 			break;
834 		if (timer1->tmr_device < timer->tmr_device)
835 			continue;
836 		if (timer1->tmr_subdevice > timer->tmr_subdevice)
837 			break;
838 		if (timer1->tmr_subdevice < timer->tmr_subdevice)
839 			continue;
840 		/* conflicts.. */
841 		up(&register_mutex);
842 		return -EBUSY;
843 	}
844 	list_add_tail(&timer->device_list, p);
845 	up(&register_mutex);
846 	return 0;
847 }
848 
849 static int snd_timer_unregister(snd_timer_t *timer)
850 {
851 	struct list_head *p, *n;
852 	snd_timer_instance_t *ti;
853 
854 	snd_assert(timer != NULL, return -ENXIO);
855 	down(&register_mutex);
856 	if (! list_empty(&timer->open_list_head)) {
857 		snd_printk(KERN_WARNING "timer 0x%lx is busy?\n", (long)timer);
858 		list_for_each_safe(p, n, &timer->open_list_head) {
859 			list_del_init(p);
860 			ti = (snd_timer_instance_t *)list_entry(p, snd_timer_instance_t, open_list);
861 			ti->timer = NULL;
862 		}
863 	}
864 	list_del(&timer->device_list);
865 	up(&register_mutex);
866 	return snd_timer_free(timer);
867 }
868 
869 static int snd_timer_dev_unregister(snd_device_t *device)
870 {
871 	snd_timer_t *timer = device->device_data;
872 	return snd_timer_unregister(timer);
873 }
874 
875 void snd_timer_notify(snd_timer_t *timer, enum sndrv_timer_event event, struct timespec *tstamp)
876 {
877 	unsigned long flags;
878 	unsigned long resolution = 0;
879 	snd_timer_instance_t *ti, *ts;
880 	struct list_head *p, *n;
881 
882 	snd_runtime_check(timer->hw.flags & SNDRV_TIMER_HW_SLAVE, return);
883 	snd_assert(event >= SNDRV_TIMER_EVENT_MSTART && event <= SNDRV_TIMER_EVENT_MRESUME, return);
884 	spin_lock_irqsave(&timer->lock, flags);
885 	if (event == SNDRV_TIMER_EVENT_MSTART ||
886 	    event == SNDRV_TIMER_EVENT_MCONTINUE ||
887 	    event == SNDRV_TIMER_EVENT_MRESUME) {
888 		if (timer->hw.c_resolution)
889 			resolution = timer->hw.c_resolution(timer);
890 		else
891 			resolution = timer->hw.resolution;
892 	}
893 	list_for_each(p, &timer->active_list_head) {
894 		ti = (snd_timer_instance_t *)list_entry(p, snd_timer_instance_t, active_list);
895 		if (ti->ccallback)
896 			ti->ccallback(ti, event, tstamp, resolution);
897 		list_for_each(n, &ti->slave_active_head) {
898 			ts = (snd_timer_instance_t *)list_entry(n, snd_timer_instance_t, active_list);
899 			if (ts->ccallback)
900 				ts->ccallback(ts, event, tstamp, resolution);
901 		}
902 	}
903 	spin_unlock_irqrestore(&timer->lock, flags);
904 }
905 
906 /*
907  * exported functions for global timers
908  */
909 int snd_timer_global_new(char *id, int device, snd_timer_t **rtimer)
910 {
911 	snd_timer_id_t tid;
912 
913 	tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
914 	tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
915 	tid.card = -1;
916 	tid.device = device;
917 	tid.subdevice = 0;
918 	return snd_timer_new(NULL, id, &tid, rtimer);
919 }
920 
921 int snd_timer_global_free(snd_timer_t *timer)
922 {
923 	return snd_timer_free(timer);
924 }
925 
926 int snd_timer_global_register(snd_timer_t *timer)
927 {
928 	snd_device_t dev;
929 
930 	memset(&dev, 0, sizeof(dev));
931 	dev.device_data = timer;
932 	return snd_timer_dev_register(&dev);
933 }
934 
935 int snd_timer_global_unregister(snd_timer_t *timer)
936 {
937 	return snd_timer_unregister(timer);
938 }
939 
940 /*
941  *  System timer
942  */
943 
944 struct snd_timer_system_private {
945 	struct timer_list tlist;
946 	struct timer * timer;
947 	unsigned long last_expires;
948 	unsigned long last_jiffies;
949 	unsigned long correction;
950 };
951 
952 static void snd_timer_s_function(unsigned long data)
953 {
954 	snd_timer_t *timer = (snd_timer_t *)data;
955 	struct snd_timer_system_private *priv = timer->private_data;
956 	unsigned long jiff = jiffies;
957 	if (time_after(jiff, priv->last_expires))
958 		priv->correction = (long)jiff - (long)priv->last_expires;
959 	snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
960 }
961 
962 static int snd_timer_s_start(snd_timer_t * timer)
963 {
964 	struct snd_timer_system_private *priv;
965 	unsigned long njiff;
966 
967 	priv = (struct snd_timer_system_private *) timer->private_data;
968 	njiff = (priv->last_jiffies = jiffies);
969 	if (priv->correction > timer->sticks - 1) {
970 		priv->correction -= timer->sticks - 1;
971 		njiff++;
972 	} else {
973 		njiff += timer->sticks - priv->correction;
974 		priv->correction -= timer->sticks;
975 	}
976 	priv->last_expires = priv->tlist.expires = njiff;
977 	add_timer(&priv->tlist);
978 	return 0;
979 }
980 
981 static int snd_timer_s_stop(snd_timer_t * timer)
982 {
983 	struct snd_timer_system_private *priv;
984 	unsigned long jiff;
985 
986 	priv = (struct snd_timer_system_private *) timer->private_data;
987 	del_timer(&priv->tlist);
988 	jiff = jiffies;
989 	if (time_before(jiff, priv->last_expires))
990 		timer->sticks = priv->last_expires - jiff;
991 	else
992 		timer->sticks = 1;
993 	return 0;
994 }
995 
996 static struct _snd_timer_hardware snd_timer_system =
997 {
998 	.flags =	SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
999 	.resolution =	1000000000L / HZ,
1000 	.ticks =	10000000L,
1001 	.start =	snd_timer_s_start,
1002 	.stop =		snd_timer_s_stop
1003 };
1004 
1005 static void snd_timer_free_system(snd_timer_t *timer)
1006 {
1007 	kfree(timer->private_data);
1008 }
1009 
1010 static int snd_timer_register_system(void)
1011 {
1012 	snd_timer_t *timer;
1013 	struct snd_timer_system_private *priv;
1014 	int err;
1015 
1016 	if ((err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer)) < 0)
1017 		return err;
1018 	strcpy(timer->name, "system timer");
1019 	timer->hw = snd_timer_system;
1020 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1021 	if (priv == NULL) {
1022 		snd_timer_free(timer);
1023 		return -ENOMEM;
1024 	}
1025 	init_timer(&priv->tlist);
1026 	priv->tlist.function = snd_timer_s_function;
1027 	priv->tlist.data = (unsigned long) timer;
1028 	timer->private_data = priv;
1029 	timer->private_free = snd_timer_free_system;
1030 	return snd_timer_global_register(timer);
1031 }
1032 
1033 /*
1034  *  Info interface
1035  */
1036 
1037 static void snd_timer_proc_read(snd_info_entry_t *entry,
1038 				snd_info_buffer_t * buffer)
1039 {
1040 	unsigned long flags;
1041 	snd_timer_t *timer;
1042 	snd_timer_instance_t *ti;
1043 	struct list_head *p, *q;
1044 
1045 	down(&register_mutex);
1046 	list_for_each(p, &snd_timer_list) {
1047 		timer = (snd_timer_t *)list_entry(p, snd_timer_t, device_list);
1048 		switch (timer->tmr_class) {
1049 		case SNDRV_TIMER_CLASS_GLOBAL:
1050 			snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1051 			break;
1052 		case SNDRV_TIMER_CLASS_CARD:
1053 			snd_iprintf(buffer, "C%i-%i: ", timer->card->number, timer->tmr_device);
1054 			break;
1055 		case SNDRV_TIMER_CLASS_PCM:
1056 			snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number, timer->tmr_device, timer->tmr_subdevice);
1057 			break;
1058 		default:
1059 			snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class, timer->card ? timer->card->number : -1, timer->tmr_device, timer->tmr_subdevice);
1060 		}
1061 		snd_iprintf(buffer, "%s :", timer->name);
1062 		if (timer->hw.resolution)
1063 			snd_iprintf(buffer, " %lu.%03luus (%lu ticks)", timer->hw.resolution / 1000, timer->hw.resolution % 1000, timer->hw.ticks);
1064 		if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1065 			snd_iprintf(buffer, " SLAVE");
1066 		snd_iprintf(buffer, "\n");
1067 		spin_lock_irqsave(&timer->lock, flags);
1068 		list_for_each(q, &timer->open_list_head) {
1069 			ti = (snd_timer_instance_t *)list_entry(q, snd_timer_instance_t, open_list);
1070 			snd_iprintf(buffer, "  Client %s : %s : lost interrupts %li\n",
1071 					ti->owner ? ti->owner : "unknown",
1072 					ti->flags & (SNDRV_TIMER_IFLG_START|SNDRV_TIMER_IFLG_RUNNING) ? "running" : "stopped",
1073 					ti->lost);
1074 		}
1075 		spin_unlock_irqrestore(&timer->lock, flags);
1076 	}
1077 	up(&register_mutex);
1078 }
1079 
1080 /*
1081  *  USER SPACE interface
1082  */
1083 
1084 static void snd_timer_user_interrupt(snd_timer_instance_t *timeri,
1085 				     unsigned long resolution,
1086 				     unsigned long ticks)
1087 {
1088 	snd_timer_user_t *tu = timeri->callback_data;
1089 	snd_timer_read_t *r;
1090 	int prev;
1091 
1092 	spin_lock(&tu->qlock);
1093 	if (tu->qused > 0) {
1094 		prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1095 		r = &tu->queue[prev];
1096 		if (r->resolution == resolution) {
1097 			r->ticks += ticks;
1098 			goto __wake;
1099 		}
1100 	}
1101 	if (tu->qused >= tu->queue_size) {
1102 		tu->overrun++;
1103 	} else {
1104 		r = &tu->queue[tu->qtail++];
1105 		tu->qtail %= tu->queue_size;
1106 		r->resolution = resolution;
1107 		r->ticks = ticks;
1108 		tu->qused++;
1109 	}
1110       __wake:
1111 	spin_unlock(&tu->qlock);
1112 	kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1113 	wake_up(&tu->qchange_sleep);
1114 }
1115 
1116 static void snd_timer_user_append_to_tqueue(snd_timer_user_t *tu, snd_timer_tread_t *tread)
1117 {
1118 	if (tu->qused >= tu->queue_size) {
1119 		tu->overrun++;
1120 	} else {
1121 		memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1122 		tu->qtail %= tu->queue_size;
1123 		tu->qused++;
1124 	}
1125 }
1126 
1127 static void snd_timer_user_ccallback(snd_timer_instance_t *timeri,
1128 				     enum sndrv_timer_event event,
1129 				     struct timespec *tstamp,
1130 				     unsigned long resolution)
1131 {
1132 	snd_timer_user_t *tu = timeri->callback_data;
1133 	snd_timer_tread_t r1;
1134 
1135 	if (event >= SNDRV_TIMER_EVENT_START && event <= SNDRV_TIMER_EVENT_PAUSE)
1136 		tu->tstamp = *tstamp;
1137 	if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1138 		return;
1139 	r1.event = event;
1140 	r1.tstamp = *tstamp;
1141 	r1.val = resolution;
1142 	spin_lock(&tu->qlock);
1143 	snd_timer_user_append_to_tqueue(tu, &r1);
1144 	spin_unlock(&tu->qlock);
1145 	kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1146 	wake_up(&tu->qchange_sleep);
1147 }
1148 
1149 static void snd_timer_user_tinterrupt(snd_timer_instance_t *timeri,
1150 				      unsigned long resolution,
1151 				      unsigned long ticks)
1152 {
1153 	snd_timer_user_t *tu = timeri->callback_data;
1154 	snd_timer_tread_t *r, r1;
1155 	struct timespec tstamp;
1156 	int prev, append = 0;
1157 
1158 	snd_timestamp_zero(&tstamp);
1159 	spin_lock(&tu->qlock);
1160 	if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION)|(1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1161 		spin_unlock(&tu->qlock);
1162 		return;
1163 	}
1164 	if (tu->last_resolution != resolution || ticks > 0)
1165 		snd_timestamp_now(&tstamp, 1);
1166 	if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) && tu->last_resolution != resolution) {
1167 		r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1168 		r1.tstamp = tstamp;
1169 		r1.val = resolution;
1170 		snd_timer_user_append_to_tqueue(tu, &r1);
1171 		tu->last_resolution = resolution;
1172 		append++;
1173 	}
1174 	if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1175 		goto __wake;
1176 	if (ticks == 0)
1177 		goto __wake;
1178 	if (tu->qused > 0) {
1179 		prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1180 		r = &tu->tqueue[prev];
1181 		if (r->event == SNDRV_TIMER_EVENT_TICK) {
1182 			r->tstamp = tstamp;
1183 			r->val += ticks;
1184 			append++;
1185 			goto __wake;
1186 		}
1187 	}
1188 	r1.event = SNDRV_TIMER_EVENT_TICK;
1189 	r1.tstamp = tstamp;
1190 	r1.val = ticks;
1191 	snd_timer_user_append_to_tqueue(tu, &r1);
1192 	append++;
1193       __wake:
1194 	spin_unlock(&tu->qlock);
1195 	if (append == 0)
1196 		return;
1197 	kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1198 	wake_up(&tu->qchange_sleep);
1199 }
1200 
1201 static int snd_timer_user_open(struct inode *inode, struct file *file)
1202 {
1203 	snd_timer_user_t *tu;
1204 
1205 	tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1206 	if (tu == NULL)
1207 		return -ENOMEM;
1208 	spin_lock_init(&tu->qlock);
1209 	init_waitqueue_head(&tu->qchange_sleep);
1210 	init_MUTEX(&tu->tread_sem);
1211 	tu->ticks = 1;
1212 	tu->queue_size = 128;
1213 	tu->queue = (snd_timer_read_t *)kmalloc(tu->queue_size * sizeof(snd_timer_read_t), GFP_KERNEL);
1214 	if (tu->queue == NULL) {
1215 		kfree(tu);
1216 		return -ENOMEM;
1217 	}
1218 	file->private_data = tu;
1219 	return 0;
1220 }
1221 
1222 static int snd_timer_user_release(struct inode *inode, struct file *file)
1223 {
1224 	snd_timer_user_t *tu;
1225 
1226 	if (file->private_data) {
1227 		tu = file->private_data;
1228 		file->private_data = NULL;
1229 		fasync_helper(-1, file, 0, &tu->fasync);
1230 		if (tu->timeri)
1231 			snd_timer_close(tu->timeri);
1232 		kfree(tu->queue);
1233 		kfree(tu->tqueue);
1234 		kfree(tu);
1235 	}
1236 	return 0;
1237 }
1238 
1239 static void snd_timer_user_zero_id(snd_timer_id_t *id)
1240 {
1241 	id->dev_class = SNDRV_TIMER_CLASS_NONE;
1242 	id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1243 	id->card = -1;
1244 	id->device = -1;
1245 	id->subdevice = -1;
1246 }
1247 
1248 static void snd_timer_user_copy_id(snd_timer_id_t *id, snd_timer_t *timer)
1249 {
1250 	id->dev_class = timer->tmr_class;
1251 	id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1252 	id->card = timer->card ? timer->card->number : -1;
1253 	id->device = timer->tmr_device;
1254 	id->subdevice = timer->tmr_subdevice;
1255 }
1256 
1257 static int snd_timer_user_next_device(snd_timer_id_t __user *_tid)
1258 {
1259 	snd_timer_id_t id;
1260 	snd_timer_t *timer;
1261 	struct list_head *p;
1262 
1263 	if (copy_from_user(&id, _tid, sizeof(id)))
1264 		return -EFAULT;
1265 	down(&register_mutex);
1266 	if (id.dev_class < 0) {		/* first item */
1267 		if (list_empty(&snd_timer_list))
1268 			snd_timer_user_zero_id(&id);
1269 		else {
1270 			timer = (snd_timer_t *)list_entry(snd_timer_list.next, snd_timer_t, device_list);
1271 			snd_timer_user_copy_id(&id, timer);
1272 		}
1273 	} else {
1274 		switch (id.dev_class) {
1275 		case SNDRV_TIMER_CLASS_GLOBAL:
1276 			id.device = id.device < 0 ? 0 : id.device + 1;
1277 			list_for_each(p, &snd_timer_list) {
1278 				timer = (snd_timer_t *)list_entry(p, snd_timer_t, device_list);
1279 				if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1280 					snd_timer_user_copy_id(&id, timer);
1281 					break;
1282 				}
1283 				if (timer->tmr_device >= id.device) {
1284 					snd_timer_user_copy_id(&id, timer);
1285 					break;
1286 				}
1287 			}
1288 			if (p == &snd_timer_list)
1289 				snd_timer_user_zero_id(&id);
1290 			break;
1291 		case SNDRV_TIMER_CLASS_CARD:
1292 		case SNDRV_TIMER_CLASS_PCM:
1293 			if (id.card < 0) {
1294 				id.card = 0;
1295 			} else {
1296 				if (id.card < 0) {
1297 					id.card = 0;
1298 				} else {
1299 					if (id.device < 0) {
1300 						id.device = 0;
1301 					} else {
1302 						id.subdevice = id.subdevice < 0 ? 0 : id.subdevice + 1;
1303 					}
1304 				}
1305 			}
1306 			list_for_each(p, &snd_timer_list) {
1307 				timer = (snd_timer_t *)list_entry(p, snd_timer_t, device_list);
1308 				if (timer->tmr_class > id.dev_class) {
1309 					snd_timer_user_copy_id(&id, timer);
1310 					break;
1311 				}
1312 				if (timer->tmr_class < id.dev_class)
1313 					continue;
1314 				if (timer->card->number > id.card) {
1315 					snd_timer_user_copy_id(&id, timer);
1316 					break;
1317 				}
1318 				if (timer->card->number < id.card)
1319 					continue;
1320 				if (timer->tmr_device > id.device) {
1321 					snd_timer_user_copy_id(&id, timer);
1322 					break;
1323 				}
1324 				if (timer->tmr_device < id.device)
1325 					continue;
1326 				if (timer->tmr_subdevice > id.subdevice) {
1327 					snd_timer_user_copy_id(&id, timer);
1328 					break;
1329 				}
1330 				if (timer->tmr_subdevice < id.subdevice)
1331 					continue;
1332 				snd_timer_user_copy_id(&id, timer);
1333 				break;
1334 			}
1335 			if (p == &snd_timer_list)
1336 				snd_timer_user_zero_id(&id);
1337 			break;
1338 		default:
1339 			snd_timer_user_zero_id(&id);
1340 		}
1341 	}
1342 	up(&register_mutex);
1343 	if (copy_to_user(_tid, &id, sizeof(*_tid)))
1344 		return -EFAULT;
1345 	return 0;
1346 }
1347 
1348 static int snd_timer_user_ginfo(struct file *file, snd_timer_ginfo_t __user *_ginfo)
1349 {
1350 	snd_timer_ginfo_t *ginfo;
1351 	snd_timer_id_t tid;
1352 	snd_timer_t *t;
1353 	struct list_head *p;
1354 	int err = 0;
1355 
1356 	ginfo = kmalloc(sizeof(*ginfo), GFP_KERNEL);
1357 	if (! ginfo)
1358 		return -ENOMEM;
1359 	if (copy_from_user(ginfo, _ginfo, sizeof(*ginfo))) {
1360 		kfree(ginfo);
1361 		return -EFAULT;
1362 	}
1363 	tid = ginfo->tid;
1364 	memset(ginfo, 0, sizeof(*ginfo));
1365 	ginfo->tid = tid;
1366 	down(&register_mutex);
1367 	t = snd_timer_find(&tid);
1368 	if (t != NULL) {
1369 		ginfo->card = t->card ? t->card->number : -1;
1370 		if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1371 			ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1372 		strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1373 		strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1374 		ginfo->resolution = t->hw.resolution;
1375 		if (t->hw.resolution_min > 0) {
1376 			ginfo->resolution_min = t->hw.resolution_min;
1377 			ginfo->resolution_max = t->hw.resolution_max;
1378 		}
1379 		list_for_each(p, &t->open_list_head) {
1380 			ginfo->clients++;
1381 		}
1382 	} else {
1383 		err = -ENODEV;
1384 	}
1385 	up(&register_mutex);
1386 	if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1387 		err = -EFAULT;
1388 	kfree(ginfo);
1389 	return err;
1390 }
1391 
1392 static int snd_timer_user_gparams(struct file *file, snd_timer_gparams_t __user *_gparams)
1393 {
1394 	snd_timer_gparams_t gparams;
1395 	snd_timer_t *t;
1396 	int err;
1397 
1398 	if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1399 		return -EFAULT;
1400 	down(&register_mutex);
1401 	t = snd_timer_find(&gparams.tid);
1402 	if (t != NULL) {
1403 		if (list_empty(&t->open_list_head)) {
1404 			if (t->hw.set_period)
1405 				err = t->hw.set_period(t, gparams.period_num, gparams.period_den);
1406 			else
1407 				err = -ENOSYS;
1408 		} else {
1409 			err = -EBUSY;
1410 		}
1411 	} else {
1412 		err = -ENODEV;
1413 	}
1414 	up(&register_mutex);
1415 	return err;
1416 }
1417 
1418 static int snd_timer_user_gstatus(struct file *file, snd_timer_gstatus_t __user *_gstatus)
1419 {
1420 	snd_timer_gstatus_t gstatus;
1421 	snd_timer_id_t tid;
1422 	snd_timer_t *t;
1423 	int err = 0;
1424 
1425 	if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1426 		return -EFAULT;
1427 	tid = gstatus.tid;
1428 	memset(&gstatus, 0, sizeof(gstatus));
1429 	gstatus.tid = tid;
1430 	down(&register_mutex);
1431 	t = snd_timer_find(&tid);
1432 	if (t != NULL) {
1433 		if (t->hw.c_resolution)
1434 			gstatus.resolution = t->hw.c_resolution(t);
1435 		else
1436 			gstatus.resolution = t->hw.resolution;
1437 		if (t->hw.precise_resolution) {
1438 			t->hw.precise_resolution(t, &gstatus.resolution_num, &gstatus.resolution_den);
1439 		} else {
1440 			gstatus.resolution_num = gstatus.resolution;
1441 			gstatus.resolution_den = 1000000000uL;
1442 		}
1443 	} else {
1444 		err = -ENODEV;
1445 	}
1446 	up(&register_mutex);
1447 	if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1448 		err = -EFAULT;
1449 	return err;
1450 }
1451 
1452 static int snd_timer_user_tselect(struct file *file, snd_timer_select_t __user *_tselect)
1453 {
1454 	snd_timer_user_t *tu;
1455 	snd_timer_select_t tselect;
1456 	char str[32];
1457 	int err = 0;
1458 
1459 	tu = file->private_data;
1460 	down(&tu->tread_sem);
1461 	if (tu->timeri) {
1462 		snd_timer_close(tu->timeri);
1463 		tu->timeri = NULL;
1464 	}
1465 	if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1466 		err = -EFAULT;
1467 		goto __err;
1468 	}
1469 	sprintf(str, "application %i", current->pid);
1470 	if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1471 		tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1472 	if ((err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid)) < 0)
1473 		goto __err;
1474 
1475 	kfree(tu->queue);
1476 	tu->queue = NULL;
1477 	kfree(tu->tqueue);
1478 	tu->tqueue = NULL;
1479 	if (tu->tread) {
1480 		tu->tqueue = (snd_timer_tread_t *)kmalloc(tu->queue_size * sizeof(snd_timer_tread_t), GFP_KERNEL);
1481 		if (tu->tqueue == NULL)
1482 			err = -ENOMEM;
1483 	} else {
1484 		tu->queue = (snd_timer_read_t *)kmalloc(tu->queue_size * sizeof(snd_timer_read_t), GFP_KERNEL);
1485 		if (tu->queue == NULL)
1486 			err = -ENOMEM;
1487 	}
1488 
1489       	if (err < 0) {
1490 		snd_timer_close(tu->timeri);
1491       		tu->timeri = NULL;
1492       	} else {
1493 		tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1494 		tu->timeri->callback = tu->tread ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1495 		tu->timeri->ccallback = snd_timer_user_ccallback;
1496 		tu->timeri->callback_data = (void *)tu;
1497 	}
1498 
1499       __err:
1500       	up(&tu->tread_sem);
1501 	return err;
1502 }
1503 
1504 static int snd_timer_user_info(struct file *file, snd_timer_info_t __user *_info)
1505 {
1506 	snd_timer_user_t *tu;
1507 	snd_timer_info_t *info;
1508 	snd_timer_t *t;
1509 	int err = 0;
1510 
1511 	tu = file->private_data;
1512 	snd_assert(tu->timeri != NULL, return -ENXIO);
1513 	t = tu->timeri->timer;
1514 	snd_assert(t != NULL, return -ENXIO);
1515 
1516 	info = kzalloc(sizeof(*info), GFP_KERNEL);
1517 	if (! info)
1518 		return -ENOMEM;
1519 	info->card = t->card ? t->card->number : -1;
1520 	if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1521 		info->flags |= SNDRV_TIMER_FLG_SLAVE;
1522 	strlcpy(info->id, t->id, sizeof(info->id));
1523 	strlcpy(info->name, t->name, sizeof(info->name));
1524 	info->resolution = t->hw.resolution;
1525 	if (copy_to_user(_info, info, sizeof(*_info)))
1526 		err = -EFAULT;
1527 	kfree(info);
1528 	return err;
1529 }
1530 
1531 static int snd_timer_user_params(struct file *file, snd_timer_params_t __user *_params)
1532 {
1533 	snd_timer_user_t *tu;
1534 	snd_timer_params_t params;
1535 	snd_timer_t *t;
1536 	snd_timer_read_t *tr;
1537 	snd_timer_tread_t *ttr;
1538 	int err;
1539 
1540 	tu = file->private_data;
1541 	snd_assert(tu->timeri != NULL, return -ENXIO);
1542 	t = tu->timeri->timer;
1543 	snd_assert(t != NULL, return -ENXIO);
1544 	if (copy_from_user(&params, _params, sizeof(params)))
1545 		return -EFAULT;
1546 	if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE) && params.ticks < 1) {
1547 		err = -EINVAL;
1548 		goto _end;
1549 	}
1550 	if (params.queue_size > 0 && (params.queue_size < 32 || params.queue_size > 1024)) {
1551 		err = -EINVAL;
1552 		goto _end;
1553 	}
1554 	if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1555 			      (1<<SNDRV_TIMER_EVENT_TICK)|
1556 			      (1<<SNDRV_TIMER_EVENT_START)|
1557 			      (1<<SNDRV_TIMER_EVENT_STOP)|
1558 			      (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1559 			      (1<<SNDRV_TIMER_EVENT_PAUSE)|
1560 			      (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1561 			      (1<<SNDRV_TIMER_EVENT_RESUME)|
1562 			      (1<<SNDRV_TIMER_EVENT_MSTART)|
1563 			      (1<<SNDRV_TIMER_EVENT_MSTOP)|
1564 			      (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1565 			      (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1566 			      (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1567 			      (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1568 		err = -EINVAL;
1569 		goto _end;
1570 	}
1571 	snd_timer_stop(tu->timeri);
1572 	spin_lock_irq(&t->lock);
1573 	tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1574 			       SNDRV_TIMER_IFLG_EXCLUSIVE|
1575 			       SNDRV_TIMER_IFLG_EARLY_EVENT);
1576 	if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1577 		tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1578 	if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1579 		tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1580 	if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1581 		tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1582 	spin_unlock_irq(&t->lock);
1583 	if (params.queue_size > 0 && (unsigned int)tu->queue_size != params.queue_size) {
1584 		if (tu->tread) {
1585 			ttr = (snd_timer_tread_t *)kmalloc(params.queue_size * sizeof(snd_timer_tread_t), GFP_KERNEL);
1586 			if (ttr) {
1587 				kfree(tu->tqueue);
1588 				tu->queue_size = params.queue_size;
1589 				tu->tqueue = ttr;
1590 			}
1591 		} else {
1592 			tr = (snd_timer_read_t *)kmalloc(params.queue_size * sizeof(snd_timer_read_t), GFP_KERNEL);
1593 			if (tr) {
1594 				kfree(tu->queue);
1595 				tu->queue_size = params.queue_size;
1596 				tu->queue = tr;
1597 			}
1598 		}
1599 	}
1600 	tu->qhead = tu->qtail = tu->qused = 0;
1601 	if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1602 		if (tu->tread) {
1603 			snd_timer_tread_t tread;
1604 			tread.event = SNDRV_TIMER_EVENT_EARLY;
1605 			tread.tstamp.tv_sec = 0;
1606 			tread.tstamp.tv_nsec = 0;
1607 			tread.val = 0;
1608 			snd_timer_user_append_to_tqueue(tu, &tread);
1609 		} else {
1610 			snd_timer_read_t *r = &tu->queue[0];
1611 			r->resolution = 0;
1612 			r->ticks = 0;
1613 			tu->qused++;
1614 			tu->qtail++;
1615 		}
1616 
1617 	}
1618 	tu->filter = params.filter;
1619 	tu->ticks = params.ticks;
1620 	err = 0;
1621  _end:
1622 	if (copy_to_user(_params, &params, sizeof(params)))
1623 		return -EFAULT;
1624 	return err;
1625 }
1626 
1627 static int snd_timer_user_status(struct file *file, snd_timer_status_t __user *_status)
1628 {
1629 	snd_timer_user_t *tu;
1630 	snd_timer_status_t status;
1631 
1632 	tu = file->private_data;
1633 	snd_assert(tu->timeri != NULL, return -ENXIO);
1634 	memset(&status, 0, sizeof(status));
1635 	status.tstamp = tu->tstamp;
1636 	status.resolution = snd_timer_resolution(tu->timeri);
1637 	status.lost = tu->timeri->lost;
1638 	status.overrun = tu->overrun;
1639 	spin_lock_irq(&tu->qlock);
1640 	status.queue = tu->qused;
1641 	spin_unlock_irq(&tu->qlock);
1642 	if (copy_to_user(_status, &status, sizeof(status)))
1643 		return -EFAULT;
1644 	return 0;
1645 }
1646 
1647 static int snd_timer_user_start(struct file *file)
1648 {
1649 	int err;
1650 	snd_timer_user_t *tu;
1651 
1652 	tu = file->private_data;
1653 	snd_assert(tu->timeri != NULL, return -ENXIO);
1654 	snd_timer_stop(tu->timeri);
1655 	tu->timeri->lost = 0;
1656 	tu->last_resolution = 0;
1657 	return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1658 }
1659 
1660 static int snd_timer_user_stop(struct file *file)
1661 {
1662 	int err;
1663 	snd_timer_user_t *tu;
1664 
1665 	tu = file->private_data;
1666 	snd_assert(tu->timeri != NULL, return -ENXIO);
1667 	return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1668 }
1669 
1670 static int snd_timer_user_continue(struct file *file)
1671 {
1672 	int err;
1673 	snd_timer_user_t *tu;
1674 
1675 	tu = file->private_data;
1676 	snd_assert(tu->timeri != NULL, return -ENXIO);
1677 	tu->timeri->lost = 0;
1678 	return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1679 }
1680 
1681 static int snd_timer_user_pause(struct file *file)
1682 {
1683 	int err;
1684 	snd_timer_user_t *tu;
1685 
1686 	tu = file->private_data;
1687 	snd_assert(tu->timeri != NULL, return -ENXIO);
1688 	return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1689 }
1690 
1691 enum {
1692 	SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1693 	SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1694 	SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1695 	SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1696 };
1697 
1698 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1699 {
1700 	snd_timer_user_t *tu;
1701 	void __user *argp = (void __user *)arg;
1702 	int __user *p = argp;
1703 
1704 	tu = file->private_data;
1705 	switch (cmd) {
1706 	case SNDRV_TIMER_IOCTL_PVERSION:
1707 		return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1708 	case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1709 		return snd_timer_user_next_device(argp);
1710 	case SNDRV_TIMER_IOCTL_TREAD:
1711 	{
1712 		int xarg;
1713 
1714 		down(&tu->tread_sem);
1715 		if (tu->timeri)	{	/* too late */
1716 			up(&tu->tread_sem);
1717 			return -EBUSY;
1718 		}
1719 		if (get_user(xarg, p)) {
1720 			up(&tu->tread_sem);
1721 			return -EFAULT;
1722 		}
1723 		tu->tread = xarg ? 1 : 0;
1724 		up(&tu->tread_sem);
1725 		return 0;
1726 	}
1727 	case SNDRV_TIMER_IOCTL_GINFO:
1728 		return snd_timer_user_ginfo(file, argp);
1729 	case SNDRV_TIMER_IOCTL_GPARAMS:
1730 		return snd_timer_user_gparams(file, argp);
1731 	case SNDRV_TIMER_IOCTL_GSTATUS:
1732 		return snd_timer_user_gstatus(file, argp);
1733 	case SNDRV_TIMER_IOCTL_SELECT:
1734 		return snd_timer_user_tselect(file, argp);
1735 	case SNDRV_TIMER_IOCTL_INFO:
1736 		return snd_timer_user_info(file, argp);
1737 	case SNDRV_TIMER_IOCTL_PARAMS:
1738 		return snd_timer_user_params(file, argp);
1739 	case SNDRV_TIMER_IOCTL_STATUS:
1740 		return snd_timer_user_status(file, argp);
1741 	case SNDRV_TIMER_IOCTL_START:
1742 	case SNDRV_TIMER_IOCTL_START_OLD:
1743 		return snd_timer_user_start(file);
1744 	case SNDRV_TIMER_IOCTL_STOP:
1745 	case SNDRV_TIMER_IOCTL_STOP_OLD:
1746 		return snd_timer_user_stop(file);
1747 	case SNDRV_TIMER_IOCTL_CONTINUE:
1748 	case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1749 		return snd_timer_user_continue(file);
1750 	case SNDRV_TIMER_IOCTL_PAUSE:
1751 	case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1752 		return snd_timer_user_pause(file);
1753 	}
1754 	return -ENOTTY;
1755 }
1756 
1757 static int snd_timer_user_fasync(int fd, struct file * file, int on)
1758 {
1759 	snd_timer_user_t *tu;
1760 	int err;
1761 
1762 	tu = file->private_data;
1763 	err = fasync_helper(fd, file, on, &tu->fasync);
1764         if (err < 0)
1765 		return err;
1766 	return 0;
1767 }
1768 
1769 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer, size_t count, loff_t *offset)
1770 {
1771 	snd_timer_user_t *tu;
1772 	long result = 0, unit;
1773 	int err = 0;
1774 
1775 	tu = file->private_data;
1776 	unit = tu->tread ? sizeof(snd_timer_tread_t) : sizeof(snd_timer_read_t);
1777 	spin_lock_irq(&tu->qlock);
1778 	while ((long)count - result >= unit) {
1779 		while (!tu->qused) {
1780 			wait_queue_t wait;
1781 
1782 			if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1783 				err = -EAGAIN;
1784 				break;
1785 			}
1786 
1787 			set_current_state(TASK_INTERRUPTIBLE);
1788 			init_waitqueue_entry(&wait, current);
1789 			add_wait_queue(&tu->qchange_sleep, &wait);
1790 
1791 			spin_unlock_irq(&tu->qlock);
1792 			schedule();
1793 			spin_lock_irq(&tu->qlock);
1794 
1795 			remove_wait_queue(&tu->qchange_sleep, &wait);
1796 
1797 			if (signal_pending(current)) {
1798 				err = -ERESTARTSYS;
1799 				break;
1800 			}
1801 		}
1802 
1803 		spin_unlock_irq(&tu->qlock);
1804 		if (err < 0)
1805 			goto _error;
1806 
1807 		if (tu->tread) {
1808 			if (copy_to_user(buffer, &tu->tqueue[tu->qhead++], sizeof(snd_timer_tread_t))) {
1809 				err = -EFAULT;
1810 				goto _error;
1811 			}
1812 		} else {
1813 			if (copy_to_user(buffer, &tu->queue[tu->qhead++], sizeof(snd_timer_read_t))) {
1814 				err = -EFAULT;
1815 				goto _error;
1816 			}
1817 		}
1818 
1819 		tu->qhead %= tu->queue_size;
1820 
1821 		result += unit;
1822 		buffer += unit;
1823 
1824 		spin_lock_irq(&tu->qlock);
1825 		tu->qused--;
1826 	}
1827 	spin_unlock_irq(&tu->qlock);
1828  _error:
1829 	return result > 0 ? result : err;
1830 }
1831 
1832 static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
1833 {
1834         unsigned int mask;
1835         snd_timer_user_t *tu;
1836 
1837         tu = file->private_data;
1838 
1839         poll_wait(file, &tu->qchange_sleep, wait);
1840 
1841 	mask = 0;
1842 	if (tu->qused)
1843 		mask |= POLLIN | POLLRDNORM;
1844 
1845 	return mask;
1846 }
1847 
1848 #ifdef CONFIG_COMPAT
1849 #include "timer_compat.c"
1850 #else
1851 #define snd_timer_user_ioctl_compat	NULL
1852 #endif
1853 
1854 static struct file_operations snd_timer_f_ops =
1855 {
1856 	.owner =	THIS_MODULE,
1857 	.read =		snd_timer_user_read,
1858 	.open =		snd_timer_user_open,
1859 	.release =	snd_timer_user_release,
1860 	.poll =		snd_timer_user_poll,
1861 	.unlocked_ioctl =	snd_timer_user_ioctl,
1862 	.compat_ioctl =	snd_timer_user_ioctl_compat,
1863 	.fasync = 	snd_timer_user_fasync,
1864 };
1865 
1866 static snd_minor_t snd_timer_reg =
1867 {
1868 	.comment =	"timer",
1869 	.f_ops =	&snd_timer_f_ops,
1870 };
1871 
1872 /*
1873  *  ENTRY functions
1874  */
1875 
1876 static snd_info_entry_t *snd_timer_proc_entry = NULL;
1877 
1878 static int __init alsa_timer_init(void)
1879 {
1880 	int err;
1881 	snd_info_entry_t *entry;
1882 
1883 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
1884 	snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1, "system timer");
1885 #endif
1886 	if ((entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL)) != NULL) {
1887 		entry->c.text.read_size = SNDRV_TIMER_DEVICES * 128;
1888 		entry->c.text.read = snd_timer_proc_read;
1889 		if (snd_info_register(entry) < 0) {
1890 			snd_info_free_entry(entry);
1891 			entry = NULL;
1892 		}
1893 	}
1894 	snd_timer_proc_entry = entry;
1895 	if ((err = snd_timer_register_system()) < 0)
1896 		snd_printk(KERN_ERR "unable to register system timer (%i)\n", err);
1897 	if ((err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER,
1898 					NULL, 0, &snd_timer_reg, "timer"))<0)
1899 		snd_printk(KERN_ERR "unable to register timer device (%i)\n", err);
1900 	return 0;
1901 }
1902 
1903 static void __exit alsa_timer_exit(void)
1904 {
1905 	struct list_head *p, *n;
1906 
1907 	snd_unregister_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0);
1908 	/* unregister the system timer */
1909 	list_for_each_safe(p, n, &snd_timer_list) {
1910 		snd_timer_t *timer = (snd_timer_t *)list_entry(p, snd_timer_t, device_list);
1911 		snd_timer_unregister(timer);
1912 	}
1913 	if (snd_timer_proc_entry) {
1914 		snd_info_unregister(snd_timer_proc_entry);
1915 		snd_timer_proc_entry = NULL;
1916 	}
1917 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
1918 	snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
1919 #endif
1920 }
1921 
1922 module_init(alsa_timer_init)
1923 module_exit(alsa_timer_exit)
1924 
1925 EXPORT_SYMBOL(snd_timer_open);
1926 EXPORT_SYMBOL(snd_timer_close);
1927 EXPORT_SYMBOL(snd_timer_resolution);
1928 EXPORT_SYMBOL(snd_timer_start);
1929 EXPORT_SYMBOL(snd_timer_stop);
1930 EXPORT_SYMBOL(snd_timer_continue);
1931 EXPORT_SYMBOL(snd_timer_pause);
1932 EXPORT_SYMBOL(snd_timer_new);
1933 EXPORT_SYMBOL(snd_timer_notify);
1934 EXPORT_SYMBOL(snd_timer_global_new);
1935 EXPORT_SYMBOL(snd_timer_global_free);
1936 EXPORT_SYMBOL(snd_timer_global_register);
1937 EXPORT_SYMBOL(snd_timer_global_unregister);
1938 EXPORT_SYMBOL(snd_timer_interrupt);
1939