sound/core/timer.c

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