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