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TOMOYO Linux Cross Reference
Linux/sound/core/timer.c

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

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