~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

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

Version: ~ [ linux-5.10-rc5 ] ~ [ linux-5.9.10 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.79 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.159 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.208 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.245 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.245 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.85 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /*
  2  *  Timers abstract layer
  3  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
  4  *
  5  *
  6  *   This program is free software; you can redistribute it and/or modify
  7  *   it under the terms of the GNU General Public License as published by
  8  *   the Free Software Foundation; either version 2 of the License, or
  9  *   (at your option) any later version.
 10  *
 11  *   This program is distributed in the hope that it will be useful,
 12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14  *   GNU General Public License for more details.
 15  *
 16  *   You should have received a copy of the GNU General Public License
 17  *   along with this program; if not, write to the Free Software
 18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 19  *
 20  */
 21 
 22 #include <linux/delay.h>
 23 #include <linux/init.h>
 24 #include <linux/slab.h>
 25 #include <linux/time.h>
 26 #include <linux/mutex.h>
 27 #include <linux/device.h>
 28 #include <linux/module.h>
 29 #include <linux/string.h>
 30 #include <linux/sched/signal.h>
 31 #include <sound/core.h>
 32 #include <sound/timer.h>
 33 #include <sound/control.h>
 34 #include <sound/info.h>
 35 #include <sound/minors.h>
 36 #include <sound/initval.h>
 37 #include <linux/kmod.h>
 38 
 39 /* internal flags */
 40 #define SNDRV_TIMER_IFLG_PAUSED         0x00010000
 41 
 42 #if IS_ENABLED(CONFIG_SND_HRTIMER)
 43 #define DEFAULT_TIMER_LIMIT 4
 44 #else
 45 #define DEFAULT_TIMER_LIMIT 1
 46 #endif
 47 
 48 static int timer_limit = DEFAULT_TIMER_LIMIT;
 49 static int timer_tstamp_monotonic = 1;
 50 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.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 module_param(timer_tstamp_monotonic, int, 0444);
 56 MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
 57 
 58 MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
 59 MODULE_ALIAS("devname:snd/timer");
 60 
 61 struct snd_timer_user {
 62         struct snd_timer_instance *timeri;
 63         int tread;              /* enhanced read with timestamps and events */
 64         unsigned long ticks;
 65         unsigned long overrun;
 66         int qhead;
 67         int qtail;
 68         int qused;
 69         int queue_size;
 70         bool disconnected;
 71         struct snd_timer_read *queue;
 72         struct snd_timer_tread *tqueue;
 73         spinlock_t qlock;
 74         unsigned long last_resolution;
 75         unsigned int filter;
 76         struct timespec tstamp;         /* trigger tstamp */
 77         wait_queue_head_t qchange_sleep;
 78         struct fasync_struct *fasync;
 79         struct mutex ioctl_lock;
 80 };
 81 
 82 /* list of timers */
 83 static LIST_HEAD(snd_timer_list);
 84 
 85 /* list of slave instances */
 86 static LIST_HEAD(snd_timer_slave_list);
 87 
 88 /* lock for slave active lists */
 89 static DEFINE_SPINLOCK(slave_active_lock);
 90 
 91 static DEFINE_MUTEX(register_mutex);
 92 
 93 static int snd_timer_free(struct snd_timer *timer);
 94 static int snd_timer_dev_free(struct snd_device *device);
 95 static int snd_timer_dev_register(struct snd_device *device);
 96 static int snd_timer_dev_disconnect(struct snd_device *device);
 97 
 98 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
 99 
100 /*
101  * create a timer instance with the given owner string.
102  * when timer is not NULL, increments the module counter
103  */
104 static struct snd_timer_instance *snd_timer_instance_new(char *owner,
105                                                          struct snd_timer *timer)
106 {
107         struct snd_timer_instance *timeri;
108         timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
109         if (timeri == NULL)
110                 return NULL;
111         timeri->owner = kstrdup(owner, GFP_KERNEL);
112         if (! timeri->owner) {
113                 kfree(timeri);
114                 return NULL;
115         }
116         INIT_LIST_HEAD(&timeri->open_list);
117         INIT_LIST_HEAD(&timeri->active_list);
118         INIT_LIST_HEAD(&timeri->ack_list);
119         INIT_LIST_HEAD(&timeri->slave_list_head);
120         INIT_LIST_HEAD(&timeri->slave_active_head);
121 
122         timeri->timer = timer;
123         if (timer && !try_module_get(timer->module)) {
124                 kfree(timeri->owner);
125                 kfree(timeri);
126                 return NULL;
127         }
128 
129         return timeri;
130 }
131 
132 /*
133  * find a timer instance from the given timer id
134  */
135 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
136 {
137         struct snd_timer *timer = NULL;
138 
139         list_for_each_entry(timer, &snd_timer_list, device_list) {
140                 if (timer->tmr_class != tid->dev_class)
141                         continue;
142                 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
143                      timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
144                     (timer->card == NULL ||
145                      timer->card->number != tid->card))
146                         continue;
147                 if (timer->tmr_device != tid->device)
148                         continue;
149                 if (timer->tmr_subdevice != tid->subdevice)
150                         continue;
151                 return timer;
152         }
153         return NULL;
154 }
155 
156 #ifdef CONFIG_MODULES
157 
158 static void snd_timer_request(struct snd_timer_id *tid)
159 {
160         switch (tid->dev_class) {
161         case SNDRV_TIMER_CLASS_GLOBAL:
162                 if (tid->device < timer_limit)
163                         request_module("snd-timer-%i", tid->device);
164                 break;
165         case SNDRV_TIMER_CLASS_CARD:
166         case SNDRV_TIMER_CLASS_PCM:
167                 if (tid->card < snd_ecards_limit)
168                         request_module("snd-card-%i", tid->card);
169                 break;
170         default:
171                 break;
172         }
173 }
174 
175 #endif
176 
177 /*
178  * look for a master instance matching with the slave id of the given slave.
179  * when found, relink the open_link of the slave.
180  *
181  * call this with register_mutex down.
182  */
183 static int snd_timer_check_slave(struct snd_timer_instance *slave)
184 {
185         struct snd_timer *timer;
186         struct snd_timer_instance *master;
187 
188         /* FIXME: it's really dumb to look up all entries.. */
189         list_for_each_entry(timer, &snd_timer_list, device_list) {
190                 list_for_each_entry(master, &timer->open_list_head, open_list) {
191                         if (slave->slave_class == master->slave_class &&
192                             slave->slave_id == master->slave_id) {
193                                 if (master->timer->num_instances >=
194                                     master->timer->max_instances)
195                                         return -EBUSY;
196                                 list_move_tail(&slave->open_list,
197                                                &master->slave_list_head);
198                                 master->timer->num_instances++;
199                                 spin_lock_irq(&slave_active_lock);
200                                 slave->master = master;
201                                 slave->timer = master->timer;
202                                 spin_unlock_irq(&slave_active_lock);
203                                 return 0;
204                         }
205                 }
206         }
207         return 0;
208 }
209 
210 /*
211  * look for slave instances matching with the slave id of the given master.
212  * when found, relink the open_link of slaves.
213  *
214  * call this with register_mutex down.
215  */
216 static int snd_timer_check_master(struct snd_timer_instance *master)
217 {
218         struct snd_timer_instance *slave, *tmp;
219 
220         /* check all pending slaves */
221         list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
222                 if (slave->slave_class == master->slave_class &&
223                     slave->slave_id == master->slave_id) {
224                         if (master->timer->num_instances >=
225                             master->timer->max_instances)
226                                 return -EBUSY;
227                         list_move_tail(&slave->open_list, &master->slave_list_head);
228                         master->timer->num_instances++;
229                         spin_lock_irq(&slave_active_lock);
230                         spin_lock(&master->timer->lock);
231                         slave->master = master;
232                         slave->timer = master->timer;
233                         if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
234                                 list_add_tail(&slave->active_list,
235                                               &master->slave_active_head);
236                         spin_unlock(&master->timer->lock);
237                         spin_unlock_irq(&slave_active_lock);
238                 }
239         }
240         return 0;
241 }
242 
243 static int snd_timer_close_locked(struct snd_timer_instance *timeri);
244 
245 /*
246  * open a timer instance
247  * when opening a master, the slave id must be here given.
248  */
249 int snd_timer_open(struct snd_timer_instance **ti,
250                    char *owner, struct snd_timer_id *tid,
251                    unsigned int slave_id)
252 {
253         struct snd_timer *timer;
254         struct snd_timer_instance *timeri = NULL;
255         int err;
256 
257         if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
258                 /* open a slave instance */
259                 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
260                     tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
261                         pr_debug("ALSA: timer: invalid slave class %i\n",
262                                  tid->dev_sclass);
263                         return -EINVAL;
264                 }
265                 mutex_lock(&register_mutex);
266                 timeri = snd_timer_instance_new(owner, NULL);
267                 if (!timeri) {
268                         mutex_unlock(&register_mutex);
269                         return -ENOMEM;
270                 }
271                 timeri->slave_class = tid->dev_sclass;
272                 timeri->slave_id = tid->device;
273                 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
274                 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
275                 err = snd_timer_check_slave(timeri);
276                 if (err < 0) {
277                         snd_timer_close_locked(timeri);
278                         timeri = NULL;
279                 }
280                 mutex_unlock(&register_mutex);
281                 *ti = timeri;
282                 return err;
283         }
284 
285         /* open a master instance */
286         mutex_lock(&register_mutex);
287         timer = snd_timer_find(tid);
288 #ifdef CONFIG_MODULES
289         if (!timer) {
290                 mutex_unlock(&register_mutex);
291                 snd_timer_request(tid);
292                 mutex_lock(&register_mutex);
293                 timer = snd_timer_find(tid);
294         }
295 #endif
296         if (!timer) {
297                 mutex_unlock(&register_mutex);
298                 return -ENODEV;
299         }
300         if (!list_empty(&timer->open_list_head)) {
301                 timeri = list_entry(timer->open_list_head.next,
302                                     struct snd_timer_instance, open_list);
303                 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
304                         mutex_unlock(&register_mutex);
305                         return -EBUSY;
306                 }
307         }
308         if (timer->num_instances >= timer->max_instances) {
309                 mutex_unlock(&register_mutex);
310                 return -EBUSY;
311         }
312         timeri = snd_timer_instance_new(owner, timer);
313         if (!timeri) {
314                 mutex_unlock(&register_mutex);
315                 return -ENOMEM;
316         }
317         /* take a card refcount for safe disconnection */
318         if (timer->card)
319                 get_device(&timer->card->card_dev);
320         timeri->slave_class = tid->dev_sclass;
321         timeri->slave_id = slave_id;
322 
323         if (list_empty(&timer->open_list_head) && timer->hw.open) {
324                 int err = timer->hw.open(timer);
325                 if (err) {
326                         kfree(timeri->owner);
327                         kfree(timeri);
328 
329                         if (timer->card)
330                                 put_device(&timer->card->card_dev);
331                         module_put(timer->module);
332                         mutex_unlock(&register_mutex);
333                         return err;
334                 }
335         }
336 
337         list_add_tail(&timeri->open_list, &timer->open_list_head);
338         timer->num_instances++;
339         err = snd_timer_check_master(timeri);
340         if (err < 0) {
341                 snd_timer_close_locked(timeri);
342                 timeri = NULL;
343         }
344         mutex_unlock(&register_mutex);
345         *ti = timeri;
346         return err;
347 }
348 EXPORT_SYMBOL(snd_timer_open);
349 
350 /*
351  * close a timer instance
352  * call this with register_mutex down.
353  */
354 static int snd_timer_close_locked(struct snd_timer_instance *timeri)
355 {
356         struct snd_timer *timer = NULL;
357         struct snd_timer_instance *slave, *tmp;
358 
359         list_del(&timeri->open_list);
360 
361         /* force to stop the timer */
362         snd_timer_stop(timeri);
363 
364         timer = timeri->timer;
365         if (timer) {
366                 timer->num_instances--;
367                 /* wait, until the active callback is finished */
368                 spin_lock_irq(&timer->lock);
369                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
370                         spin_unlock_irq(&timer->lock);
371                         udelay(10);
372                         spin_lock_irq(&timer->lock);
373                 }
374                 spin_unlock_irq(&timer->lock);
375 
376                 /* remove slave links */
377                 spin_lock_irq(&slave_active_lock);
378                 spin_lock(&timer->lock);
379                 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
380                                          open_list) {
381                         list_move_tail(&slave->open_list, &snd_timer_slave_list);
382                         timer->num_instances--;
383                         slave->master = NULL;
384                         slave->timer = NULL;
385                         list_del_init(&slave->ack_list);
386                         list_del_init(&slave->active_list);
387                 }
388                 spin_unlock(&timer->lock);
389                 spin_unlock_irq(&slave_active_lock);
390 
391                 /* slave doesn't need to release timer resources below */
392                 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
393                         timer = NULL;
394         }
395 
396         if (timeri->private_free)
397                 timeri->private_free(timeri);
398         kfree(timeri->owner);
399         kfree(timeri);
400 
401         if (timer) {
402                 if (list_empty(&timer->open_list_head) && timer->hw.close)
403                         timer->hw.close(timer);
404                 /* release a card refcount for safe disconnection */
405                 if (timer->card)
406                         put_device(&timer->card->card_dev);
407                 module_put(timer->module);
408         }
409 
410         return 0;
411 }
412 
413 /*
414  * close a timer instance
415  */
416 int snd_timer_close(struct snd_timer_instance *timeri)
417 {
418         int err;
419 
420         if (snd_BUG_ON(!timeri))
421                 return -ENXIO;
422 
423         mutex_lock(&register_mutex);
424         err = snd_timer_close_locked(timeri);
425         mutex_unlock(&register_mutex);
426         return err;
427 }
428 EXPORT_SYMBOL(snd_timer_close);
429 
430 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
431 {
432         struct snd_timer * timer;
433 
434         if (timeri == NULL)
435                 return 0;
436         timer = timeri->timer;
437         if (timer) {
438                 if (timer->hw.c_resolution)
439                         return timer->hw.c_resolution(timer);
440                 return timer->hw.resolution;
441         }
442         return 0;
443 }
444 EXPORT_SYMBOL(snd_timer_resolution);
445 
446 static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
447 {
448         struct snd_timer *timer;
449         unsigned long resolution = 0;
450         struct snd_timer_instance *ts;
451         struct timespec tstamp;
452 
453         if (timer_tstamp_monotonic)
454                 ktime_get_ts(&tstamp);
455         else
456                 getnstimeofday(&tstamp);
457         if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
458                        event > SNDRV_TIMER_EVENT_PAUSE))
459                 return;
460         if (event == SNDRV_TIMER_EVENT_START ||
461             event == SNDRV_TIMER_EVENT_CONTINUE)
462                 resolution = snd_timer_resolution(ti);
463         if (ti->ccallback)
464                 ti->ccallback(ti, event, &tstamp, resolution);
465         if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
466                 return;
467         timer = ti->timer;
468         if (timer == NULL)
469                 return;
470         if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
471                 return;
472         list_for_each_entry(ts, &ti->slave_active_head, active_list)
473                 if (ts->ccallback)
474                         ts->ccallback(ts, event + 100, &tstamp, resolution);
475 }
476 
477 /* start/continue a master timer */
478 static int snd_timer_start1(struct snd_timer_instance *timeri,
479                             bool start, unsigned long ticks)
480 {
481         struct snd_timer *timer;
482         int result;
483         unsigned long flags;
484 
485         timer = timeri->timer;
486         if (!timer)
487                 return -EINVAL;
488 
489         spin_lock_irqsave(&timer->lock, flags);
490         if (timer->card && timer->card->shutdown) {
491                 result = -ENODEV;
492                 goto unlock;
493         }
494         if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
495                              SNDRV_TIMER_IFLG_START)) {
496                 result = -EBUSY;
497                 goto unlock;
498         }
499 
500         if (start)
501                 timeri->ticks = timeri->cticks = ticks;
502         else if (!timeri->cticks)
503                 timeri->cticks = 1;
504         timeri->pticks = 0;
505 
506         list_move_tail(&timeri->active_list, &timer->active_list_head);
507         if (timer->running) {
508                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
509                         goto __start_now;
510                 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
511                 timeri->flags |= SNDRV_TIMER_IFLG_START;
512                 result = 1; /* delayed start */
513         } else {
514                 if (start)
515                         timer->sticks = ticks;
516                 timer->hw.start(timer);
517               __start_now:
518                 timer->running++;
519                 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
520                 result = 0;
521         }
522         snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
523                           SNDRV_TIMER_EVENT_CONTINUE);
524  unlock:
525         spin_unlock_irqrestore(&timer->lock, flags);
526         return result;
527 }
528 
529 /* start/continue a slave timer */
530 static int snd_timer_start_slave(struct snd_timer_instance *timeri,
531                                  bool start)
532 {
533         unsigned long flags;
534 
535         spin_lock_irqsave(&slave_active_lock, flags);
536         if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) {
537                 spin_unlock_irqrestore(&slave_active_lock, flags);
538                 return -EBUSY;
539         }
540         timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
541         if (timeri->master && timeri->timer) {
542                 spin_lock(&timeri->timer->lock);
543                 list_add_tail(&timeri->active_list,
544                               &timeri->master->slave_active_head);
545                 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
546                                   SNDRV_TIMER_EVENT_CONTINUE);
547                 spin_unlock(&timeri->timer->lock);
548         }
549         spin_unlock_irqrestore(&slave_active_lock, flags);
550         return 1; /* delayed start */
551 }
552 
553 /* stop/pause a master timer */
554 static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
555 {
556         struct snd_timer *timer;
557         int result = 0;
558         unsigned long flags;
559 
560         timer = timeri->timer;
561         if (!timer)
562                 return -EINVAL;
563         spin_lock_irqsave(&timer->lock, flags);
564         if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
565                                SNDRV_TIMER_IFLG_START))) {
566                 result = -EBUSY;
567                 goto unlock;
568         }
569         list_del_init(&timeri->ack_list);
570         list_del_init(&timeri->active_list);
571         if (timer->card && timer->card->shutdown)
572                 goto unlock;
573         if (stop) {
574                 timeri->cticks = timeri->ticks;
575                 timeri->pticks = 0;
576         }
577         if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
578             !(--timer->running)) {
579                 timer->hw.stop(timer);
580                 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
581                         timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
582                         snd_timer_reschedule(timer, 0);
583                         if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
584                                 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
585                                 timer->hw.start(timer);
586                         }
587                 }
588         }
589         timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
590         if (stop)
591                 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
592         else
593                 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
594         snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
595                           SNDRV_TIMER_EVENT_CONTINUE);
596  unlock:
597         spin_unlock_irqrestore(&timer->lock, flags);
598         return result;
599 }
600 
601 /* stop/pause a slave timer */
602 static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
603 {
604         unsigned long flags;
605 
606         spin_lock_irqsave(&slave_active_lock, flags);
607         if (!(timeri->flags & SNDRV_TIMER_IFLG_RUNNING)) {
608                 spin_unlock_irqrestore(&slave_active_lock, flags);
609                 return -EBUSY;
610         }
611         timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
612         if (timeri->timer) {
613                 spin_lock(&timeri->timer->lock);
614                 list_del_init(&timeri->ack_list);
615                 list_del_init(&timeri->active_list);
616                 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
617                                   SNDRV_TIMER_EVENT_CONTINUE);
618                 spin_unlock(&timeri->timer->lock);
619         }
620         spin_unlock_irqrestore(&slave_active_lock, flags);
621         return 0;
622 }
623 
624 /*
625  *  start the timer instance
626  */
627 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
628 {
629         if (timeri == NULL || ticks < 1)
630                 return -EINVAL;
631         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
632                 return snd_timer_start_slave(timeri, true);
633         else
634                 return snd_timer_start1(timeri, true, ticks);
635 }
636 EXPORT_SYMBOL(snd_timer_start);
637 
638 /*
639  * stop the timer instance.
640  *
641  * do not call this from the timer callback!
642  */
643 int snd_timer_stop(struct snd_timer_instance *timeri)
644 {
645         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
646                 return snd_timer_stop_slave(timeri, true);
647         else
648                 return snd_timer_stop1(timeri, true);
649 }
650 EXPORT_SYMBOL(snd_timer_stop);
651 
652 /*
653  * start again..  the tick is kept.
654  */
655 int snd_timer_continue(struct snd_timer_instance *timeri)
656 {
657         /* timer can continue only after pause */
658         if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
659                 return -EINVAL;
660 
661         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
662                 return snd_timer_start_slave(timeri, false);
663         else
664                 return snd_timer_start1(timeri, false, 0);
665 }
666 EXPORT_SYMBOL(snd_timer_continue);
667 
668 /*
669  * pause.. remember the ticks left
670  */
671 int snd_timer_pause(struct snd_timer_instance * timeri)
672 {
673         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
674                 return snd_timer_stop_slave(timeri, false);
675         else
676                 return snd_timer_stop1(timeri, false);
677 }
678 EXPORT_SYMBOL(snd_timer_pause);
679 
680 /*
681  * reschedule the timer
682  *
683  * start pending instances and check the scheduling ticks.
684  * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
685  */
686 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
687 {
688         struct snd_timer_instance *ti;
689         unsigned long ticks = ~0UL;
690 
691         list_for_each_entry(ti, &timer->active_list_head, active_list) {
692                 if (ti->flags & SNDRV_TIMER_IFLG_START) {
693                         ti->flags &= ~SNDRV_TIMER_IFLG_START;
694                         ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
695                         timer->running++;
696                 }
697                 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
698                         if (ticks > ti->cticks)
699                                 ticks = ti->cticks;
700                 }
701         }
702         if (ticks == ~0UL) {
703                 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
704                 return;
705         }
706         if (ticks > timer->hw.ticks)
707                 ticks = timer->hw.ticks;
708         if (ticks_left != ticks)
709                 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
710         timer->sticks = ticks;
711 }
712 
713 /*
714  * timer tasklet
715  *
716  */
717 static void snd_timer_tasklet(unsigned long arg)
718 {
719         struct snd_timer *timer = (struct snd_timer *) arg;
720         struct snd_timer_instance *ti;
721         struct list_head *p;
722         unsigned long resolution, ticks;
723         unsigned long flags;
724 
725         if (timer->card && timer->card->shutdown)
726                 return;
727 
728         spin_lock_irqsave(&timer->lock, flags);
729         /* now process all callbacks */
730         while (!list_empty(&timer->sack_list_head)) {
731                 p = timer->sack_list_head.next;         /* get first item */
732                 ti = list_entry(p, struct snd_timer_instance, ack_list);
733 
734                 /* remove from ack_list and make empty */
735                 list_del_init(p);
736 
737                 ticks = ti->pticks;
738                 ti->pticks = 0;
739                 resolution = ti->resolution;
740 
741                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
742                 spin_unlock(&timer->lock);
743                 if (ti->callback)
744                         ti->callback(ti, resolution, ticks);
745                 spin_lock(&timer->lock);
746                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
747         }
748         spin_unlock_irqrestore(&timer->lock, flags);
749 }
750 
751 /*
752  * timer interrupt
753  *
754  * ticks_left is usually equal to timer->sticks.
755  *
756  */
757 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
758 {
759         struct snd_timer_instance *ti, *ts, *tmp;
760         unsigned long resolution, ticks;
761         struct list_head *p, *ack_list_head;
762         unsigned long flags;
763         int use_tasklet = 0;
764 
765         if (timer == NULL)
766                 return;
767 
768         if (timer->card && timer->card->shutdown)
769                 return;
770 
771         spin_lock_irqsave(&timer->lock, flags);
772 
773         /* remember the current resolution */
774         if (timer->hw.c_resolution)
775                 resolution = timer->hw.c_resolution(timer);
776         else
777                 resolution = timer->hw.resolution;
778 
779         /* loop for all active instances
780          * Here we cannot use list_for_each_entry because the active_list of a
781          * processed instance is relinked to done_list_head before the callback
782          * is called.
783          */
784         list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
785                                  active_list) {
786                 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
787                         continue;
788                 ti->pticks += ticks_left;
789                 ti->resolution = resolution;
790                 if (ti->cticks < ticks_left)
791                         ti->cticks = 0;
792                 else
793                         ti->cticks -= ticks_left;
794                 if (ti->cticks) /* not expired */
795                         continue;
796                 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
797                         ti->cticks = ti->ticks;
798                 } else {
799                         ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
800                         --timer->running;
801                         list_del_init(&ti->active_list);
802                 }
803                 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
804                     (ti->flags & SNDRV_TIMER_IFLG_FAST))
805                         ack_list_head = &timer->ack_list_head;
806                 else
807                         ack_list_head = &timer->sack_list_head;
808                 if (list_empty(&ti->ack_list))
809                         list_add_tail(&ti->ack_list, ack_list_head);
810                 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
811                         ts->pticks = ti->pticks;
812                         ts->resolution = resolution;
813                         if (list_empty(&ts->ack_list))
814                                 list_add_tail(&ts->ack_list, ack_list_head);
815                 }
816         }
817         if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
818                 snd_timer_reschedule(timer, timer->sticks);
819         if (timer->running) {
820                 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
821                         timer->hw.stop(timer);
822                         timer->flags |= SNDRV_TIMER_FLG_CHANGE;
823                 }
824                 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
825                     (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
826                         /* restart timer */
827                         timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
828                         timer->hw.start(timer);
829                 }
830         } else {
831                 timer->hw.stop(timer);
832         }
833 
834         /* now process all fast callbacks */
835         while (!list_empty(&timer->ack_list_head)) {
836                 p = timer->ack_list_head.next;          /* get first item */
837                 ti = list_entry(p, struct snd_timer_instance, ack_list);
838 
839                 /* remove from ack_list and make empty */
840                 list_del_init(p);
841 
842                 ticks = ti->pticks;
843                 ti->pticks = 0;
844 
845                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
846                 spin_unlock(&timer->lock);
847                 if (ti->callback)
848                         ti->callback(ti, resolution, ticks);
849                 spin_lock(&timer->lock);
850                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
851         }
852 
853         /* do we have any slow callbacks? */
854         use_tasklet = !list_empty(&timer->sack_list_head);
855         spin_unlock_irqrestore(&timer->lock, flags);
856 
857         if (use_tasklet)
858                 tasklet_schedule(&timer->task_queue);
859 }
860 EXPORT_SYMBOL(snd_timer_interrupt);
861 
862 /*
863 
864  */
865 
866 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
867                   struct snd_timer **rtimer)
868 {
869         struct snd_timer *timer;
870         int err;
871         static struct snd_device_ops ops = {
872                 .dev_free = snd_timer_dev_free,
873                 .dev_register = snd_timer_dev_register,
874                 .dev_disconnect = snd_timer_dev_disconnect,
875         };
876 
877         if (snd_BUG_ON(!tid))
878                 return -EINVAL;
879         if (rtimer)
880                 *rtimer = NULL;
881         timer = kzalloc(sizeof(*timer), GFP_KERNEL);
882         if (!timer)
883                 return -ENOMEM;
884         timer->tmr_class = tid->dev_class;
885         timer->card = card;
886         timer->tmr_device = tid->device;
887         timer->tmr_subdevice = tid->subdevice;
888         if (id)
889                 strlcpy(timer->id, id, sizeof(timer->id));
890         timer->sticks = 1;
891         INIT_LIST_HEAD(&timer->device_list);
892         INIT_LIST_HEAD(&timer->open_list_head);
893         INIT_LIST_HEAD(&timer->active_list_head);
894         INIT_LIST_HEAD(&timer->ack_list_head);
895         INIT_LIST_HEAD(&timer->sack_list_head);
896         spin_lock_init(&timer->lock);
897         tasklet_init(&timer->task_queue, snd_timer_tasklet,
898                      (unsigned long)timer);
899         timer->max_instances = 1000; /* default limit per timer */
900         if (card != NULL) {
901                 timer->module = card->module;
902                 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
903                 if (err < 0) {
904                         snd_timer_free(timer);
905                         return err;
906                 }
907         }
908         if (rtimer)
909                 *rtimer = timer;
910         return 0;
911 }
912 EXPORT_SYMBOL(snd_timer_new);
913 
914 static int snd_timer_free(struct snd_timer *timer)
915 {
916         if (!timer)
917                 return 0;
918 
919         mutex_lock(&register_mutex);
920         if (! list_empty(&timer->open_list_head)) {
921                 struct list_head *p, *n;
922                 struct snd_timer_instance *ti;
923                 pr_warn("ALSA: timer %p is busy?\n", timer);
924                 list_for_each_safe(p, n, &timer->open_list_head) {
925                         list_del_init(p);
926                         ti = list_entry(p, struct snd_timer_instance, open_list);
927                         ti->timer = NULL;
928                 }
929         }
930         list_del(&timer->device_list);
931         mutex_unlock(&register_mutex);
932 
933         if (timer->private_free)
934                 timer->private_free(timer);
935         kfree(timer);
936         return 0;
937 }
938 
939 static int snd_timer_dev_free(struct snd_device *device)
940 {
941         struct snd_timer *timer = device->device_data;
942         return snd_timer_free(timer);
943 }
944 
945 static int snd_timer_dev_register(struct snd_device *dev)
946 {
947         struct snd_timer *timer = dev->device_data;
948         struct snd_timer *timer1;
949 
950         if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
951                 return -ENXIO;
952         if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
953             !timer->hw.resolution && timer->hw.c_resolution == NULL)
954                 return -EINVAL;
955 
956         mutex_lock(&register_mutex);
957         list_for_each_entry(timer1, &snd_timer_list, device_list) {
958                 if (timer1->tmr_class > timer->tmr_class)
959                         break;
960                 if (timer1->tmr_class < timer->tmr_class)
961                         continue;
962                 if (timer1->card && timer->card) {
963                         if (timer1->card->number > timer->card->number)
964                                 break;
965                         if (timer1->card->number < timer->card->number)
966                                 continue;
967                 }
968                 if (timer1->tmr_device > timer->tmr_device)
969                         break;
970                 if (timer1->tmr_device < timer->tmr_device)
971                         continue;
972                 if (timer1->tmr_subdevice > timer->tmr_subdevice)
973                         break;
974                 if (timer1->tmr_subdevice < timer->tmr_subdevice)
975                         continue;
976                 /* conflicts.. */
977                 mutex_unlock(&register_mutex);
978                 return -EBUSY;
979         }
980         list_add_tail(&timer->device_list, &timer1->device_list);
981         mutex_unlock(&register_mutex);
982         return 0;
983 }
984 
985 static int snd_timer_dev_disconnect(struct snd_device *device)
986 {
987         struct snd_timer *timer = device->device_data;
988         struct snd_timer_instance *ti;
989 
990         mutex_lock(&register_mutex);
991         list_del_init(&timer->device_list);
992         /* wake up pending sleepers */
993         list_for_each_entry(ti, &timer->open_list_head, open_list) {
994                 if (ti->disconnect)
995                         ti->disconnect(ti);
996         }
997         mutex_unlock(&register_mutex);
998         return 0;
999 }
1000 
1001 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
1002 {
1003         unsigned long flags;
1004         unsigned long resolution = 0;
1005         struct snd_timer_instance *ti, *ts;
1006 
1007         if (timer->card && timer->card->shutdown)
1008                 return;
1009         if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
1010                 return;
1011         if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
1012                        event > SNDRV_TIMER_EVENT_MRESUME))
1013                 return;
1014         spin_lock_irqsave(&timer->lock, flags);
1015         if (event == SNDRV_TIMER_EVENT_MSTART ||
1016             event == SNDRV_TIMER_EVENT_MCONTINUE ||
1017             event == SNDRV_TIMER_EVENT_MRESUME) {
1018                 if (timer->hw.c_resolution)
1019                         resolution = timer->hw.c_resolution(timer);
1020                 else
1021                         resolution = timer->hw.resolution;
1022         }
1023         list_for_each_entry(ti, &timer->active_list_head, active_list) {
1024                 if (ti->ccallback)
1025                         ti->ccallback(ti, event, tstamp, resolution);
1026                 list_for_each_entry(ts, &ti->slave_active_head, active_list)
1027                         if (ts->ccallback)
1028                                 ts->ccallback(ts, event, tstamp, resolution);
1029         }
1030         spin_unlock_irqrestore(&timer->lock, flags);
1031 }
1032 EXPORT_SYMBOL(snd_timer_notify);
1033 
1034 /*
1035  * exported functions for global timers
1036  */
1037 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
1038 {
1039         struct snd_timer_id tid;
1040 
1041         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
1042         tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1043         tid.card = -1;
1044         tid.device = device;
1045         tid.subdevice = 0;
1046         return snd_timer_new(NULL, id, &tid, rtimer);
1047 }
1048 EXPORT_SYMBOL(snd_timer_global_new);
1049 
1050 int snd_timer_global_free(struct snd_timer *timer)
1051 {
1052         return snd_timer_free(timer);
1053 }
1054 EXPORT_SYMBOL(snd_timer_global_free);
1055 
1056 int snd_timer_global_register(struct snd_timer *timer)
1057 {
1058         struct snd_device dev;
1059 
1060         memset(&dev, 0, sizeof(dev));
1061         dev.device_data = timer;
1062         return snd_timer_dev_register(&dev);
1063 }
1064 EXPORT_SYMBOL(snd_timer_global_register);
1065 
1066 /*
1067  *  System timer
1068  */
1069 
1070 struct snd_timer_system_private {
1071         struct timer_list tlist;
1072         struct snd_timer *snd_timer;
1073         unsigned long last_expires;
1074         unsigned long last_jiffies;
1075         unsigned long correction;
1076 };
1077 
1078 static void snd_timer_s_function(struct timer_list *t)
1079 {
1080         struct snd_timer_system_private *priv = from_timer(priv, t,
1081                                                                 tlist);
1082         struct snd_timer *timer = priv->snd_timer;
1083         unsigned long jiff = jiffies;
1084         if (time_after(jiff, priv->last_expires))
1085                 priv->correction += (long)jiff - (long)priv->last_expires;
1086         snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1087 }
1088 
1089 static int snd_timer_s_start(struct snd_timer * timer)
1090 {
1091         struct snd_timer_system_private *priv;
1092         unsigned long njiff;
1093 
1094         priv = (struct snd_timer_system_private *) timer->private_data;
1095         njiff = (priv->last_jiffies = jiffies);
1096         if (priv->correction > timer->sticks - 1) {
1097                 priv->correction -= timer->sticks - 1;
1098                 njiff++;
1099         } else {
1100                 njiff += timer->sticks - priv->correction;
1101                 priv->correction = 0;
1102         }
1103         priv->last_expires = njiff;
1104         mod_timer(&priv->tlist, njiff);
1105         return 0;
1106 }
1107 
1108 static int snd_timer_s_stop(struct snd_timer * timer)
1109 {
1110         struct snd_timer_system_private *priv;
1111         unsigned long jiff;
1112 
1113         priv = (struct snd_timer_system_private *) timer->private_data;
1114         del_timer(&priv->tlist);
1115         jiff = jiffies;
1116         if (time_before(jiff, priv->last_expires))
1117                 timer->sticks = priv->last_expires - jiff;
1118         else
1119                 timer->sticks = 1;
1120         priv->correction = 0;
1121         return 0;
1122 }
1123 
1124 static int snd_timer_s_close(struct snd_timer *timer)
1125 {
1126         struct snd_timer_system_private *priv;
1127 
1128         priv = (struct snd_timer_system_private *)timer->private_data;
1129         del_timer_sync(&priv->tlist);
1130         return 0;
1131 }
1132 
1133 static struct snd_timer_hardware snd_timer_system =
1134 {
1135         .flags =        SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
1136         .resolution =   1000000000L / HZ,
1137         .ticks =        10000000L,
1138         .close =        snd_timer_s_close,
1139         .start =        snd_timer_s_start,
1140         .stop =         snd_timer_s_stop
1141 };
1142 
1143 static void snd_timer_free_system(struct snd_timer *timer)
1144 {
1145         kfree(timer->private_data);
1146 }
1147 
1148 static int snd_timer_register_system(void)
1149 {
1150         struct snd_timer *timer;
1151         struct snd_timer_system_private *priv;
1152         int err;
1153 
1154         err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1155         if (err < 0)
1156                 return err;
1157         strcpy(timer->name, "system timer");
1158         timer->hw = snd_timer_system;
1159         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1160         if (priv == NULL) {
1161                 snd_timer_free(timer);
1162                 return -ENOMEM;
1163         }
1164         priv->snd_timer = timer;
1165         timer_setup(&priv->tlist, snd_timer_s_function, 0);
1166         timer->private_data = priv;
1167         timer->private_free = snd_timer_free_system;
1168         return snd_timer_global_register(timer);
1169 }
1170 
1171 #ifdef CONFIG_SND_PROC_FS
1172 /*
1173  *  Info interface
1174  */
1175 
1176 static void snd_timer_proc_read(struct snd_info_entry *entry,
1177                                 struct snd_info_buffer *buffer)
1178 {
1179         struct snd_timer *timer;
1180         struct snd_timer_instance *ti;
1181 
1182         mutex_lock(&register_mutex);
1183         list_for_each_entry(timer, &snd_timer_list, device_list) {
1184                 if (timer->card && timer->card->shutdown)
1185                         continue;
1186                 switch (timer->tmr_class) {
1187                 case SNDRV_TIMER_CLASS_GLOBAL:
1188                         snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1189                         break;
1190                 case SNDRV_TIMER_CLASS_CARD:
1191                         snd_iprintf(buffer, "C%i-%i: ",
1192                                     timer->card->number, timer->tmr_device);
1193                         break;
1194                 case SNDRV_TIMER_CLASS_PCM:
1195                         snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1196                                     timer->tmr_device, timer->tmr_subdevice);
1197                         break;
1198                 default:
1199                         snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1200                                     timer->card ? timer->card->number : -1,
1201                                     timer->tmr_device, timer->tmr_subdevice);
1202                 }
1203                 snd_iprintf(buffer, "%s :", timer->name);
1204                 if (timer->hw.resolution)
1205                         snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1206                                     timer->hw.resolution / 1000,
1207                                     timer->hw.resolution % 1000,
1208                                     timer->hw.ticks);
1209                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1210                         snd_iprintf(buffer, " SLAVE");
1211                 snd_iprintf(buffer, "\n");
1212                 list_for_each_entry(ti, &timer->open_list_head, open_list)
1213                         snd_iprintf(buffer, "  Client %s : %s\n",
1214                                     ti->owner ? ti->owner : "unknown",
1215                                     ti->flags & (SNDRV_TIMER_IFLG_START |
1216                                                  SNDRV_TIMER_IFLG_RUNNING)
1217                                     ? "running" : "stopped");
1218         }
1219         mutex_unlock(&register_mutex);
1220 }
1221 
1222 static struct snd_info_entry *snd_timer_proc_entry;
1223 
1224 static void __init snd_timer_proc_init(void)
1225 {
1226         struct snd_info_entry *entry;
1227 
1228         entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1229         if (entry != NULL) {
1230                 entry->c.text.read = snd_timer_proc_read;
1231                 if (snd_info_register(entry) < 0) {
1232                         snd_info_free_entry(entry);
1233                         entry = NULL;
1234                 }
1235         }
1236         snd_timer_proc_entry = entry;
1237 }
1238 
1239 static void __exit snd_timer_proc_done(void)
1240 {
1241         snd_info_free_entry(snd_timer_proc_entry);
1242 }
1243 #else /* !CONFIG_SND_PROC_FS */
1244 #define snd_timer_proc_init()
1245 #define snd_timer_proc_done()
1246 #endif
1247 
1248 /*
1249  *  USER SPACE interface
1250  */
1251 
1252 static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1253                                      unsigned long resolution,
1254                                      unsigned long ticks)
1255 {
1256         struct snd_timer_user *tu = timeri->callback_data;
1257         struct snd_timer_read *r;
1258         int prev;
1259 
1260         spin_lock(&tu->qlock);
1261         if (tu->qused > 0) {
1262                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1263                 r = &tu->queue[prev];
1264                 if (r->resolution == resolution) {
1265                         r->ticks += ticks;
1266                         goto __wake;
1267                 }
1268         }
1269         if (tu->qused >= tu->queue_size) {
1270                 tu->overrun++;
1271         } else {
1272                 r = &tu->queue[tu->qtail++];
1273                 tu->qtail %= tu->queue_size;
1274                 r->resolution = resolution;
1275                 r->ticks = ticks;
1276                 tu->qused++;
1277         }
1278       __wake:
1279         spin_unlock(&tu->qlock);
1280         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1281         wake_up(&tu->qchange_sleep);
1282 }
1283 
1284 static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1285                                             struct snd_timer_tread *tread)
1286 {
1287         if (tu->qused >= tu->queue_size) {
1288                 tu->overrun++;
1289         } else {
1290                 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1291                 tu->qtail %= tu->queue_size;
1292                 tu->qused++;
1293         }
1294 }
1295 
1296 static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1297                                      int event,
1298                                      struct timespec *tstamp,
1299                                      unsigned long resolution)
1300 {
1301         struct snd_timer_user *tu = timeri->callback_data;
1302         struct snd_timer_tread r1;
1303         unsigned long flags;
1304 
1305         if (event >= SNDRV_TIMER_EVENT_START &&
1306             event <= SNDRV_TIMER_EVENT_PAUSE)
1307                 tu->tstamp = *tstamp;
1308         if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1309                 return;
1310         memset(&r1, 0, sizeof(r1));
1311         r1.event = event;
1312         r1.tstamp = *tstamp;
1313         r1.val = resolution;
1314         spin_lock_irqsave(&tu->qlock, flags);
1315         snd_timer_user_append_to_tqueue(tu, &r1);
1316         spin_unlock_irqrestore(&tu->qlock, flags);
1317         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1318         wake_up(&tu->qchange_sleep);
1319 }
1320 
1321 static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1322 {
1323         struct snd_timer_user *tu = timeri->callback_data;
1324 
1325         tu->disconnected = true;
1326         wake_up(&tu->qchange_sleep);
1327 }
1328 
1329 static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1330                                       unsigned long resolution,
1331                                       unsigned long ticks)
1332 {
1333         struct snd_timer_user *tu = timeri->callback_data;
1334         struct snd_timer_tread *r, r1;
1335         struct timespec tstamp;
1336         int prev, append = 0;
1337 
1338         memset(&r1, 0, sizeof(r1));
1339         memset(&tstamp, 0, sizeof(tstamp));
1340         spin_lock(&tu->qlock);
1341         if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1342                            (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1343                 spin_unlock(&tu->qlock);
1344                 return;
1345         }
1346         if (tu->last_resolution != resolution || ticks > 0) {
1347                 if (timer_tstamp_monotonic)
1348                         ktime_get_ts(&tstamp);
1349                 else
1350                         getnstimeofday(&tstamp);
1351         }
1352         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1353             tu->last_resolution != resolution) {
1354                 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1355                 r1.tstamp = tstamp;
1356                 r1.val = resolution;
1357                 snd_timer_user_append_to_tqueue(tu, &r1);
1358                 tu->last_resolution = resolution;
1359                 append++;
1360         }
1361         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1362                 goto __wake;
1363         if (ticks == 0)
1364                 goto __wake;
1365         if (tu->qused > 0) {
1366                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1367                 r = &tu->tqueue[prev];
1368                 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1369                         r->tstamp = tstamp;
1370                         r->val += ticks;
1371                         append++;
1372                         goto __wake;
1373                 }
1374         }
1375         r1.event = SNDRV_TIMER_EVENT_TICK;
1376         r1.tstamp = tstamp;
1377         r1.val = ticks;
1378         snd_timer_user_append_to_tqueue(tu, &r1);
1379         append++;
1380       __wake:
1381         spin_unlock(&tu->qlock);
1382         if (append == 0)
1383                 return;
1384         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1385         wake_up(&tu->qchange_sleep);
1386 }
1387 
1388 static int realloc_user_queue(struct snd_timer_user *tu, int size)
1389 {
1390         struct snd_timer_read *queue = NULL;
1391         struct snd_timer_tread *tqueue = NULL;
1392 
1393         if (tu->tread) {
1394                 tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL);
1395                 if (!tqueue)
1396                         return -ENOMEM;
1397         } else {
1398                 queue = kcalloc(size, sizeof(*queue), GFP_KERNEL);
1399                 if (!queue)
1400                         return -ENOMEM;
1401         }
1402 
1403         spin_lock_irq(&tu->qlock);
1404         kfree(tu->queue);
1405         kfree(tu->tqueue);
1406         tu->queue_size = size;
1407         tu->queue = queue;
1408         tu->tqueue = tqueue;
1409         tu->qhead = tu->qtail = tu->qused = 0;
1410         spin_unlock_irq(&tu->qlock);
1411 
1412         return 0;
1413 }
1414 
1415 static int snd_timer_user_open(struct inode *inode, struct file *file)
1416 {
1417         struct snd_timer_user *tu;
1418         int err;
1419 
1420         err = nonseekable_open(inode, file);
1421         if (err < 0)
1422                 return err;
1423 
1424         tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1425         if (tu == NULL)
1426                 return -ENOMEM;
1427         spin_lock_init(&tu->qlock);
1428         init_waitqueue_head(&tu->qchange_sleep);
1429         mutex_init(&tu->ioctl_lock);
1430         tu->ticks = 1;
1431         if (realloc_user_queue(tu, 128) < 0) {
1432                 kfree(tu);
1433                 return -ENOMEM;
1434         }
1435         file->private_data = tu;
1436         return 0;
1437 }
1438 
1439 static int snd_timer_user_release(struct inode *inode, struct file *file)
1440 {
1441         struct snd_timer_user *tu;
1442 
1443         if (file->private_data) {
1444                 tu = file->private_data;
1445                 file->private_data = NULL;
1446                 mutex_lock(&tu->ioctl_lock);
1447                 if (tu->timeri)
1448                         snd_timer_close(tu->timeri);
1449                 mutex_unlock(&tu->ioctl_lock);
1450                 kfree(tu->queue);
1451                 kfree(tu->tqueue);
1452                 kfree(tu);
1453         }
1454         return 0;
1455 }
1456 
1457 static void snd_timer_user_zero_id(struct snd_timer_id *id)
1458 {
1459         id->dev_class = SNDRV_TIMER_CLASS_NONE;
1460         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1461         id->card = -1;
1462         id->device = -1;
1463         id->subdevice = -1;
1464 }
1465 
1466 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1467 {
1468         id->dev_class = timer->tmr_class;
1469         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1470         id->card = timer->card ? timer->card->number : -1;
1471         id->device = timer->tmr_device;
1472         id->subdevice = timer->tmr_subdevice;
1473 }
1474 
1475 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1476 {
1477         struct snd_timer_id id;
1478         struct snd_timer *timer;
1479         struct list_head *p;
1480 
1481         if (copy_from_user(&id, _tid, sizeof(id)))
1482                 return -EFAULT;
1483         mutex_lock(&register_mutex);
1484         if (id.dev_class < 0) {         /* first item */
1485                 if (list_empty(&snd_timer_list))
1486                         snd_timer_user_zero_id(&id);
1487                 else {
1488                         timer = list_entry(snd_timer_list.next,
1489                                            struct snd_timer, device_list);
1490                         snd_timer_user_copy_id(&id, timer);
1491                 }
1492         } else {
1493                 switch (id.dev_class) {
1494                 case SNDRV_TIMER_CLASS_GLOBAL:
1495                         id.device = id.device < 0 ? 0 : id.device + 1;
1496                         list_for_each(p, &snd_timer_list) {
1497                                 timer = list_entry(p, struct snd_timer, device_list);
1498                                 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1499                                         snd_timer_user_copy_id(&id, timer);
1500                                         break;
1501                                 }
1502                                 if (timer->tmr_device >= id.device) {
1503                                         snd_timer_user_copy_id(&id, timer);
1504                                         break;
1505                                 }
1506                         }
1507                         if (p == &snd_timer_list)
1508                                 snd_timer_user_zero_id(&id);
1509                         break;
1510                 case SNDRV_TIMER_CLASS_CARD:
1511                 case SNDRV_TIMER_CLASS_PCM:
1512                         if (id.card < 0) {
1513                                 id.card = 0;
1514                         } else {
1515                                 if (id.device < 0) {
1516                                         id.device = 0;
1517                                 } else {
1518                                         if (id.subdevice < 0)
1519                                                 id.subdevice = 0;
1520                                         else
1521                                                 id.subdevice++;
1522                                 }
1523                         }
1524                         list_for_each(p, &snd_timer_list) {
1525                                 timer = list_entry(p, struct snd_timer, device_list);
1526                                 if (timer->tmr_class > id.dev_class) {
1527                                         snd_timer_user_copy_id(&id, timer);
1528                                         break;
1529                                 }
1530                                 if (timer->tmr_class < id.dev_class)
1531                                         continue;
1532                                 if (timer->card->number > id.card) {
1533                                         snd_timer_user_copy_id(&id, timer);
1534                                         break;
1535                                 }
1536                                 if (timer->card->number < id.card)
1537                                         continue;
1538                                 if (timer->tmr_device > id.device) {
1539                                         snd_timer_user_copy_id(&id, timer);
1540                                         break;
1541                                 }
1542                                 if (timer->tmr_device < id.device)
1543                                         continue;
1544                                 if (timer->tmr_subdevice > id.subdevice) {
1545                                         snd_timer_user_copy_id(&id, timer);
1546                                         break;
1547                                 }
1548                                 if (timer->tmr_subdevice < id.subdevice)
1549                                         continue;
1550                                 snd_timer_user_copy_id(&id, timer);
1551                                 break;
1552                         }
1553                         if (p == &snd_timer_list)
1554                                 snd_timer_user_zero_id(&id);
1555                         break;
1556                 default:
1557                         snd_timer_user_zero_id(&id);
1558                 }
1559         }
1560         mutex_unlock(&register_mutex);
1561         if (copy_to_user(_tid, &id, sizeof(*_tid)))
1562                 return -EFAULT;
1563         return 0;
1564 }
1565 
1566 static int snd_timer_user_ginfo(struct file *file,
1567                                 struct snd_timer_ginfo __user *_ginfo)
1568 {
1569         struct snd_timer_ginfo *ginfo;
1570         struct snd_timer_id tid;
1571         struct snd_timer *t;
1572         struct list_head *p;
1573         int err = 0;
1574 
1575         ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1576         if (IS_ERR(ginfo))
1577                 return PTR_ERR(ginfo);
1578 
1579         tid = ginfo->tid;
1580         memset(ginfo, 0, sizeof(*ginfo));
1581         ginfo->tid = tid;
1582         mutex_lock(&register_mutex);
1583         t = snd_timer_find(&tid);
1584         if (t != NULL) {
1585                 ginfo->card = t->card ? t->card->number : -1;
1586                 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1587                         ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1588                 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1589                 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1590                 ginfo->resolution = t->hw.resolution;
1591                 if (t->hw.resolution_min > 0) {
1592                         ginfo->resolution_min = t->hw.resolution_min;
1593                         ginfo->resolution_max = t->hw.resolution_max;
1594                 }
1595                 list_for_each(p, &t->open_list_head) {
1596                         ginfo->clients++;
1597                 }
1598         } else {
1599                 err = -ENODEV;
1600         }
1601         mutex_unlock(&register_mutex);
1602         if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1603                 err = -EFAULT;
1604         kfree(ginfo);
1605         return err;
1606 }
1607 
1608 static int timer_set_gparams(struct snd_timer_gparams *gparams)
1609 {
1610         struct snd_timer *t;
1611         int err;
1612 
1613         mutex_lock(&register_mutex);
1614         t = snd_timer_find(&gparams->tid);
1615         if (!t) {
1616                 err = -ENODEV;
1617                 goto _error;
1618         }
1619         if (!list_empty(&t->open_list_head)) {
1620                 err = -EBUSY;
1621                 goto _error;
1622         }
1623         if (!t->hw.set_period) {
1624                 err = -ENOSYS;
1625                 goto _error;
1626         }
1627         err = t->hw.set_period(t, gparams->period_num, gparams->period_den);
1628 _error:
1629         mutex_unlock(&register_mutex);
1630         return err;
1631 }
1632 
1633 static int snd_timer_user_gparams(struct file *file,
1634                                   struct snd_timer_gparams __user *_gparams)
1635 {
1636         struct snd_timer_gparams gparams;
1637 
1638         if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1639                 return -EFAULT;
1640         return timer_set_gparams(&gparams);
1641 }
1642 
1643 static int snd_timer_user_gstatus(struct file *file,
1644                                   struct snd_timer_gstatus __user *_gstatus)
1645 {
1646         struct snd_timer_gstatus gstatus;
1647         struct snd_timer_id tid;
1648         struct snd_timer *t;
1649         int err = 0;
1650 
1651         if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1652                 return -EFAULT;
1653         tid = gstatus.tid;
1654         memset(&gstatus, 0, sizeof(gstatus));
1655         gstatus.tid = tid;
1656         mutex_lock(&register_mutex);
1657         t = snd_timer_find(&tid);
1658         if (t != NULL) {
1659                 if (t->hw.c_resolution)
1660                         gstatus.resolution = t->hw.c_resolution(t);
1661                 else
1662                         gstatus.resolution = t->hw.resolution;
1663                 if (t->hw.precise_resolution) {
1664                         t->hw.precise_resolution(t, &gstatus.resolution_num,
1665                                                  &gstatus.resolution_den);
1666                 } else {
1667                         gstatus.resolution_num = gstatus.resolution;
1668                         gstatus.resolution_den = 1000000000uL;
1669                 }
1670         } else {
1671                 err = -ENODEV;
1672         }
1673         mutex_unlock(&register_mutex);
1674         if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1675                 err = -EFAULT;
1676         return err;
1677 }
1678 
1679 static int snd_timer_user_tselect(struct file *file,
1680                                   struct snd_timer_select __user *_tselect)
1681 {
1682         struct snd_timer_user *tu;
1683         struct snd_timer_select tselect;
1684         char str[32];
1685         int err = 0;
1686 
1687         tu = file->private_data;
1688         if (tu->timeri) {
1689                 snd_timer_close(tu->timeri);
1690                 tu->timeri = NULL;
1691         }
1692         if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1693                 err = -EFAULT;
1694                 goto __err;
1695         }
1696         sprintf(str, "application %i", current->pid);
1697         if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1698                 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1699         err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1700         if (err < 0)
1701                 goto __err;
1702 
1703         tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1704         tu->timeri->callback = tu->tread
1705                         ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1706         tu->timeri->ccallback = snd_timer_user_ccallback;
1707         tu->timeri->callback_data = (void *)tu;
1708         tu->timeri->disconnect = snd_timer_user_disconnect;
1709 
1710       __err:
1711         return err;
1712 }
1713 
1714 static int snd_timer_user_info(struct file *file,
1715                                struct snd_timer_info __user *_info)
1716 {
1717         struct snd_timer_user *tu;
1718         struct snd_timer_info *info;
1719         struct snd_timer *t;
1720         int err = 0;
1721 
1722         tu = file->private_data;
1723         if (!tu->timeri)
1724                 return -EBADFD;
1725         t = tu->timeri->timer;
1726         if (!t)
1727                 return -EBADFD;
1728 
1729         info = kzalloc(sizeof(*info), GFP_KERNEL);
1730         if (! info)
1731                 return -ENOMEM;
1732         info->card = t->card ? t->card->number : -1;
1733         if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1734                 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1735         strlcpy(info->id, t->id, sizeof(info->id));
1736         strlcpy(info->name, t->name, sizeof(info->name));
1737         info->resolution = t->hw.resolution;
1738         if (copy_to_user(_info, info, sizeof(*_info)))
1739                 err = -EFAULT;
1740         kfree(info);
1741         return err;
1742 }
1743 
1744 static int snd_timer_user_params(struct file *file,
1745                                  struct snd_timer_params __user *_params)
1746 {
1747         struct snd_timer_user *tu;
1748         struct snd_timer_params params;
1749         struct snd_timer *t;
1750         int err;
1751 
1752         tu = file->private_data;
1753         if (!tu->timeri)
1754                 return -EBADFD;
1755         t = tu->timeri->timer;
1756         if (!t)
1757                 return -EBADFD;
1758         if (copy_from_user(&params, _params, sizeof(params)))
1759                 return -EFAULT;
1760         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1761                 u64 resolution;
1762 
1763                 if (params.ticks < 1) {
1764                         err = -EINVAL;
1765                         goto _end;
1766                 }
1767 
1768                 /* Don't allow resolution less than 1ms */
1769                 resolution = snd_timer_resolution(tu->timeri);
1770                 resolution *= params.ticks;
1771                 if (resolution < 1000000) {
1772                         err = -EINVAL;
1773                         goto _end;
1774                 }
1775         }
1776         if (params.queue_size > 0 &&
1777             (params.queue_size < 32 || params.queue_size > 1024)) {
1778                 err = -EINVAL;
1779                 goto _end;
1780         }
1781         if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1782                               (1<<SNDRV_TIMER_EVENT_TICK)|
1783                               (1<<SNDRV_TIMER_EVENT_START)|
1784                               (1<<SNDRV_TIMER_EVENT_STOP)|
1785                               (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1786                               (1<<SNDRV_TIMER_EVENT_PAUSE)|
1787                               (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1788                               (1<<SNDRV_TIMER_EVENT_RESUME)|
1789                               (1<<SNDRV_TIMER_EVENT_MSTART)|
1790                               (1<<SNDRV_TIMER_EVENT_MSTOP)|
1791                               (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1792                               (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1793                               (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1794                               (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1795                 err = -EINVAL;
1796                 goto _end;
1797         }
1798         snd_timer_stop(tu->timeri);
1799         spin_lock_irq(&t->lock);
1800         tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1801                                SNDRV_TIMER_IFLG_EXCLUSIVE|
1802                                SNDRV_TIMER_IFLG_EARLY_EVENT);
1803         if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1804                 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1805         if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1806                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1807         if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1808                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1809         spin_unlock_irq(&t->lock);
1810         if (params.queue_size > 0 &&
1811             (unsigned int)tu->queue_size != params.queue_size) {
1812                 err = realloc_user_queue(tu, params.queue_size);
1813                 if (err < 0)
1814                         goto _end;
1815         }
1816         spin_lock_irq(&tu->qlock);
1817         tu->qhead = tu->qtail = tu->qused = 0;
1818         if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1819                 if (tu->tread) {
1820                         struct snd_timer_tread tread;
1821                         memset(&tread, 0, sizeof(tread));
1822                         tread.event = SNDRV_TIMER_EVENT_EARLY;
1823                         tread.tstamp.tv_sec = 0;
1824                         tread.tstamp.tv_nsec = 0;
1825                         tread.val = 0;
1826                         snd_timer_user_append_to_tqueue(tu, &tread);
1827                 } else {
1828                         struct snd_timer_read *r = &tu->queue[0];
1829                         r->resolution = 0;
1830                         r->ticks = 0;
1831                         tu->qused++;
1832                         tu->qtail++;
1833                 }
1834         }
1835         tu->filter = params.filter;
1836         tu->ticks = params.ticks;
1837         spin_unlock_irq(&tu->qlock);
1838         err = 0;
1839  _end:
1840         if (copy_to_user(_params, &params, sizeof(params)))
1841                 return -EFAULT;
1842         return err;
1843 }
1844 
1845 static int snd_timer_user_status(struct file *file,
1846                                  struct snd_timer_status __user *_status)
1847 {
1848         struct snd_timer_user *tu;
1849         struct snd_timer_status status;
1850 
1851         tu = file->private_data;
1852         if (!tu->timeri)
1853                 return -EBADFD;
1854         memset(&status, 0, sizeof(status));
1855         status.tstamp = tu->tstamp;
1856         status.resolution = snd_timer_resolution(tu->timeri);
1857         status.lost = tu->timeri->lost;
1858         status.overrun = tu->overrun;
1859         spin_lock_irq(&tu->qlock);
1860         status.queue = tu->qused;
1861         spin_unlock_irq(&tu->qlock);
1862         if (copy_to_user(_status, &status, sizeof(status)))
1863                 return -EFAULT;
1864         return 0;
1865 }
1866 
1867 static int snd_timer_user_start(struct file *file)
1868 {
1869         int err;
1870         struct snd_timer_user *tu;
1871 
1872         tu = file->private_data;
1873         if (!tu->timeri)
1874                 return -EBADFD;
1875         snd_timer_stop(tu->timeri);
1876         tu->timeri->lost = 0;
1877         tu->last_resolution = 0;
1878         return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1879 }
1880 
1881 static int snd_timer_user_stop(struct file *file)
1882 {
1883         int err;
1884         struct snd_timer_user *tu;
1885 
1886         tu = file->private_data;
1887         if (!tu->timeri)
1888                 return -EBADFD;
1889         return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1890 }
1891 
1892 static int snd_timer_user_continue(struct file *file)
1893 {
1894         int err;
1895         struct snd_timer_user *tu;
1896 
1897         tu = file->private_data;
1898         if (!tu->timeri)
1899                 return -EBADFD;
1900         /* start timer instead of continue if it's not used before */
1901         if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
1902                 return snd_timer_user_start(file);
1903         tu->timeri->lost = 0;
1904         return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1905 }
1906 
1907 static int snd_timer_user_pause(struct file *file)
1908 {
1909         int err;
1910         struct snd_timer_user *tu;
1911 
1912         tu = file->private_data;
1913         if (!tu->timeri)
1914                 return -EBADFD;
1915         return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1916 }
1917 
1918 enum {
1919         SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1920         SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1921         SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1922         SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1923 };
1924 
1925 static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1926                                  unsigned long arg)
1927 {
1928         struct snd_timer_user *tu;
1929         void __user *argp = (void __user *)arg;
1930         int __user *p = argp;
1931 
1932         tu = file->private_data;
1933         switch (cmd) {
1934         case SNDRV_TIMER_IOCTL_PVERSION:
1935                 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1936         case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1937                 return snd_timer_user_next_device(argp);
1938         case SNDRV_TIMER_IOCTL_TREAD:
1939         {
1940                 int xarg, old_tread;
1941 
1942                 if (tu->timeri) /* too late */
1943                         return -EBUSY;
1944                 if (get_user(xarg, p))
1945                         return -EFAULT;
1946                 old_tread = tu->tread;
1947                 tu->tread = xarg ? 1 : 0;
1948                 if (tu->tread != old_tread &&
1949                     realloc_user_queue(tu, tu->queue_size) < 0) {
1950                         tu->tread = old_tread;
1951                         return -ENOMEM;
1952                 }
1953                 return 0;
1954         }
1955         case SNDRV_TIMER_IOCTL_GINFO:
1956                 return snd_timer_user_ginfo(file, argp);
1957         case SNDRV_TIMER_IOCTL_GPARAMS:
1958                 return snd_timer_user_gparams(file, argp);
1959         case SNDRV_TIMER_IOCTL_GSTATUS:
1960                 return snd_timer_user_gstatus(file, argp);
1961         case SNDRV_TIMER_IOCTL_SELECT:
1962                 return snd_timer_user_tselect(file, argp);
1963         case SNDRV_TIMER_IOCTL_INFO:
1964                 return snd_timer_user_info(file, argp);
1965         case SNDRV_TIMER_IOCTL_PARAMS:
1966                 return snd_timer_user_params(file, argp);
1967         case SNDRV_TIMER_IOCTL_STATUS:
1968                 return snd_timer_user_status(file, argp);
1969         case SNDRV_TIMER_IOCTL_START:
1970         case SNDRV_TIMER_IOCTL_START_OLD:
1971                 return snd_timer_user_start(file);
1972         case SNDRV_TIMER_IOCTL_STOP:
1973         case SNDRV_TIMER_IOCTL_STOP_OLD:
1974                 return snd_timer_user_stop(file);
1975         case SNDRV_TIMER_IOCTL_CONTINUE:
1976         case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1977                 return snd_timer_user_continue(file);
1978         case SNDRV_TIMER_IOCTL_PAUSE:
1979         case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1980                 return snd_timer_user_pause(file);
1981         }
1982         return -ENOTTY;
1983 }
1984 
1985 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1986                                  unsigned long arg)
1987 {
1988         struct snd_timer_user *tu = file->private_data;
1989         long ret;
1990 
1991         mutex_lock(&tu->ioctl_lock);
1992         ret = __snd_timer_user_ioctl(file, cmd, arg);
1993         mutex_unlock(&tu->ioctl_lock);
1994         return ret;
1995 }
1996 
1997 static int snd_timer_user_fasync(int fd, struct file * file, int on)
1998 {
1999         struct snd_timer_user *tu;
2000 
2001         tu = file->private_data;
2002         return fasync_helper(fd, file, on, &tu->fasync);
2003 }
2004 
2005 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2006                                    size_t count, loff_t *offset)
2007 {
2008         struct snd_timer_user *tu;
2009         long result = 0, unit;
2010         int qhead;
2011         int err = 0;
2012 
2013         tu = file->private_data;
2014         unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
2015         mutex_lock(&tu->ioctl_lock);
2016         spin_lock_irq(&tu->qlock);
2017         while ((long)count - result >= unit) {
2018                 while (!tu->qused) {
2019                         wait_queue_entry_t wait;
2020 
2021                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2022                                 err = -EAGAIN;
2023                                 goto _error;
2024                         }
2025 
2026                         set_current_state(TASK_INTERRUPTIBLE);
2027                         init_waitqueue_entry(&wait, current);
2028                         add_wait_queue(&tu->qchange_sleep, &wait);
2029 
2030                         spin_unlock_irq(&tu->qlock);
2031                         mutex_unlock(&tu->ioctl_lock);
2032                         schedule();
2033                         mutex_lock(&tu->ioctl_lock);
2034                         spin_lock_irq(&tu->qlock);
2035 
2036                         remove_wait_queue(&tu->qchange_sleep, &wait);
2037 
2038                         if (tu->disconnected) {
2039                                 err = -ENODEV;
2040                                 goto _error;
2041                         }
2042                         if (signal_pending(current)) {
2043                                 err = -ERESTARTSYS;
2044                                 goto _error;
2045                         }
2046                 }
2047 
2048                 qhead = tu->qhead++;
2049                 tu->qhead %= tu->queue_size;
2050                 tu->qused--;
2051                 spin_unlock_irq(&tu->qlock);
2052 
2053                 if (tu->tread) {
2054                         if (copy_to_user(buffer, &tu->tqueue[qhead],
2055                                          sizeof(struct snd_timer_tread)))
2056                                 err = -EFAULT;
2057                 } else {
2058                         if (copy_to_user(buffer, &tu->queue[qhead],
2059                                          sizeof(struct snd_timer_read)))
2060                                 err = -EFAULT;
2061                 }
2062 
2063                 spin_lock_irq(&tu->qlock);
2064                 if (err < 0)
2065                         goto _error;
2066                 result += unit;
2067                 buffer += unit;
2068         }
2069  _error:
2070         spin_unlock_irq(&tu->qlock);
2071         mutex_unlock(&tu->ioctl_lock);
2072         return result > 0 ? result : err;
2073 }
2074 
2075 static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
2076 {
2077         unsigned int mask;
2078         struct snd_timer_user *tu;
2079 
2080         tu = file->private_data;
2081 
2082         poll_wait(file, &tu->qchange_sleep, wait);
2083 
2084         mask = 0;
2085         spin_lock_irq(&tu->qlock);
2086         if (tu->qused)
2087                 mask |= POLLIN | POLLRDNORM;
2088         if (tu->disconnected)
2089                 mask |= POLLERR;
2090         spin_unlock_irq(&tu->qlock);
2091 
2092         return mask;
2093 }
2094 
2095 #ifdef CONFIG_COMPAT
2096 #include "timer_compat.c"
2097 #else
2098 #define snd_timer_user_ioctl_compat     NULL
2099 #endif
2100 
2101 static const struct file_operations snd_timer_f_ops =
2102 {
2103         .owner =        THIS_MODULE,
2104         .read =         snd_timer_user_read,
2105         .open =         snd_timer_user_open,
2106         .release =      snd_timer_user_release,
2107         .llseek =       no_llseek,
2108         .poll =         snd_timer_user_poll,
2109         .unlocked_ioctl =       snd_timer_user_ioctl,
2110         .compat_ioctl = snd_timer_user_ioctl_compat,
2111         .fasync =       snd_timer_user_fasync,
2112 };
2113 
2114 /* unregister the system timer */
2115 static void snd_timer_free_all(void)
2116 {
2117         struct snd_timer *timer, *n;
2118 
2119         list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2120                 snd_timer_free(timer);
2121 }
2122 
2123 static struct device timer_dev;
2124 
2125 /*
2126  *  ENTRY functions
2127  */
2128 
2129 static int __init alsa_timer_init(void)
2130 {
2131         int err;
2132 
2133         snd_device_initialize(&timer_dev, NULL);
2134         dev_set_name(&timer_dev, "timer");
2135 
2136 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2137         snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2138                               "system timer");
2139 #endif
2140 
2141         err = snd_timer_register_system();
2142         if (err < 0) {
2143                 pr_err("ALSA: unable to register system timer (%i)\n", err);
2144                 goto put_timer;
2145         }
2146 
2147         err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2148                                   &snd_timer_f_ops, NULL, &timer_dev);
2149         if (err < 0) {
2150                 pr_err("ALSA: unable to register timer device (%i)\n", err);
2151                 snd_timer_free_all();
2152                 goto put_timer;
2153         }
2154 
2155         snd_timer_proc_init();
2156         return 0;
2157 
2158 put_timer:
2159         put_device(&timer_dev);
2160         return err;
2161 }
2162 
2163 static void __exit alsa_timer_exit(void)
2164 {
2165         snd_unregister_device(&timer_dev);
2166         snd_timer_free_all();
2167         put_device(&timer_dev);
2168         snd_timer_proc_done();
2169 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2170         snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2171 #endif
2172 }
2173 
2174 module_init(alsa_timer_init)
2175 module_exit(alsa_timer_exit)
2176 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp