sound/core/timer.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Timers abstract layer
   4  *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   5  */
   6
   7 #include <linux/delay.h>
   8 #include <linux/init.h>
   9 #include <linux/slab.h>
  10 #include <linux/time.h>
  11 #include <linux/mutex.h>
  12 #include <linux/device.h>
  13 #include <linux/module.h>
  14 #include <linux/string.h>
  15 #include <linux/sched/signal.h>
  16 #include <sound/core.h>
  17 #include <sound/timer.h>
  18 #include <sound/control.h>
  19 #include <sound/info.h>
  20 #include <sound/minors.h>
  21 #include <sound/initval.h>
  22 #include <linux/kmod.h>
  23
  24 /* internal flags */
  25 #define SNDRV_TIMER_IFLG_PAUSED         0x00010000
  26 #define SNDRV_TIMER_IFLG_DEAD           0x00020000
  27
  28 #if IS_ENABLED(CONFIG_SND_HRTIMER)
  29 #define DEFAULT_TIMER_LIMIT 4
  30 #else
  31 #define DEFAULT_TIMER_LIMIT 1
  32 #endif
  33
  34 static int timer_limit = DEFAULT_TIMER_LIMIT;
  35 static int timer_tstamp_monotonic = 1;
  36 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>");
  37 MODULE_DESCRIPTION("ALSA timer interface");
  38 MODULE_LICENSE("GPL");
  39 module_param(timer_limit, int, 0444);
  40 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
  41 module_param(timer_tstamp_monotonic, int, 0444);
  42 MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
  43
  44 MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
  45 MODULE_ALIAS("devname:snd/timer");
  46
  47 struct snd_timer_user {
  48         struct snd_timer_instance *timeri;
  49         int tread;              /* enhanced read with timestamps and events */
  50         unsigned long ticks;
  51         unsigned long overrun;
  52         int qhead;
  53         int qtail;
  54         int qused;
  55         int queue_size;
  56         bool disconnected;
  57         struct snd_timer_read *queue;
  58         struct snd_timer_tread *tqueue;
  59         spinlock_t qlock;
  60         unsigned long last_resolution;
  61         unsigned int filter;
  62         struct timespec tstamp;         /* trigger tstamp */
  63         wait_queue_head_t qchange_sleep;
  64         struct snd_fasync *fasync;
  65         struct mutex ioctl_lock;
  66 };
  67
  68 /* list of timers */
  69 static LIST_HEAD(snd_timer_list);
  70
  71 /* list of slave instances */
  72 static LIST_HEAD(snd_timer_slave_list);
  73
  74 /* lock for slave active lists */
  75 static DEFINE_SPINLOCK(slave_active_lock);
  76
  77 #define MAX_SLAVE_INSTANCES     1000
  78 static int num_slaves;
  79
  80 static DEFINE_MUTEX(register_mutex);
  81
  82 static int snd_timer_free(struct snd_timer *timer);
  83 static int snd_timer_dev_free(struct snd_device *device);
  84 static int snd_timer_dev_register(struct snd_device *device);
  85 static int snd_timer_dev_disconnect(struct snd_device *device);
  86
  87 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
  88
  89 /*
  90  * create a timer instance with the given owner string.
  91  * when timer is not NULL, increments the module counter
  92  */
  93 static struct snd_timer_instance *snd_timer_instance_new(char *owner,
  94                                                          struct snd_timer *timer)
  95 {
  96         struct snd_timer_instance *timeri;
  97         timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
  98         if (timeri == NULL)
  99                 return NULL;
 100         timeri->owner = kstrdup(owner, GFP_KERNEL);
 101         if (! timeri->owner) {
 102                 kfree(timeri);
 103                 return NULL;
 104         }
 105         INIT_LIST_HEAD(&timeri->open_list);
 106         INIT_LIST_HEAD(&timeri->active_list);
 107         INIT_LIST_HEAD(&timeri->ack_list);
 108         INIT_LIST_HEAD(&timeri->slave_list_head);
 109         INIT_LIST_HEAD(&timeri->slave_active_head);
 110
 111         timeri->timer = timer;
 112         if (timer && !try_module_get(timer->module)) {
 113                 kfree(timeri->owner);
 114                 kfree(timeri);
 115                 return NULL;
 116         }
 117
 118         return timeri;
 119 }
 120
 121 /*
 122  * find a timer instance from the given timer id
 123  */
 124 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
 125 {
 126         struct snd_timer *timer = NULL;
 127
 128         list_for_each_entry(timer, &snd_timer_list, device_list) {
 129                 if (timer->tmr_class != tid->dev_class)
 130                         continue;
 131                 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
 132                      timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
 133                     (timer->card == NULL ||
 134                      timer->card->number != tid->card))
 135                         continue;
 136                 if (timer->tmr_device != tid->device)
 137                         continue;
 138                 if (timer->tmr_subdevice != tid->subdevice)
 139                         continue;
 140                 return timer;
 141         }
 142         return NULL;
 143 }
 144
 145 #ifdef CONFIG_MODULES
 146
 147 static void snd_timer_request(struct snd_timer_id *tid)
 148 {
 149         switch (tid->dev_class) {
 150         case SNDRV_TIMER_CLASS_GLOBAL:
 151                 if (tid->device < timer_limit)
 152                         request_module("snd-timer-%i", tid->device);
 153                 break;
 154         case SNDRV_TIMER_CLASS_CARD:
 155         case SNDRV_TIMER_CLASS_PCM:
 156                 if (tid->card < snd_ecards_limit)
 157                         request_module("snd-card-%i", tid->card);
 158                 break;
 159         default:
 160                 break;
 161         }
 162 }
 163
 164 #endif
 165
 166 /*
 167  * look for a master instance matching with the slave id of the given slave.
 168  * when found, relink the open_link of the slave.
 169  *
 170  * call this with register_mutex down.
 171  */
 172 static int snd_timer_check_slave(struct snd_timer_instance *slave)
 173 {
 174         struct snd_timer *timer;
 175         struct snd_timer_instance *master;
 176
 177         /* FIXME: it's really dumb to look up all entries.. */
 178         list_for_each_entry(timer, &snd_timer_list, device_list) {
 179                 list_for_each_entry(master, &timer->open_list_head, open_list) {
 180                         if (slave->slave_class == master->slave_class &&
 181                             slave->slave_id == master->slave_id) {
 182                                 if (master->timer->num_instances >=
 183                                     master->timer->max_instances)
 184                                         return -EBUSY;
 185                                 list_move_tail(&slave->open_list,
 186                                                &master->slave_list_head);
 187                                 master->timer->num_instances++;
 188                                 spin_lock_irq(&slave_active_lock);
 189                                 slave->master = master;
 190                                 slave->timer = master->timer;
 191                                 spin_unlock_irq(&slave_active_lock);
 192                                 return 0;
 193                         }
 194                 }
 195         }
 196         return 0;
 197 }
 198
 199 /*
 200  * look for slave instances matching with the slave id of the given master.
 201  * when found, relink the open_link of slaves.
 202  *
 203  * call this with register_mutex down.
 204  */
 205 static int snd_timer_check_master(struct snd_timer_instance *master)
 206 {
 207         struct snd_timer_instance *slave, *tmp;
 208
 209         /* check all pending slaves */
 210         list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
 211                 if (slave->slave_class == master->slave_class &&
 212                     slave->slave_id == master->slave_id) {
 213                         if (master->timer->num_instances >=
 214                             master->timer->max_instances)
 215                                 return -EBUSY;
 216                         list_move_tail(&slave->open_list, &master->slave_list_head);
 217                         master->timer->num_instances++;
 218                         spin_lock_irq(&slave_active_lock);
 219                         spin_lock(&master->timer->lock);
 220                         slave->master = master;
 221                         slave->timer = master->timer;
 222                         if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
 223                                 list_add_tail(&slave->active_list,
 224                                               &master->slave_active_head);
 225                         spin_unlock(&master->timer->lock);
 226                         spin_unlock_irq(&slave_active_lock);
 227                 }
 228         }
 229         return 0;
 230 }
 231
 232 static int snd_timer_close_locked(struct snd_timer_instance *timeri,
 233                                   struct device **card_devp_to_put);
 234
 235 /*
 236  * open a timer instance
 237  * when opening a master, the slave id must be here given.
 238  */
 239 int snd_timer_open(struct snd_timer_instance **ti,
 240                    char *owner, struct snd_timer_id *tid,
 241                    unsigned int slave_id)
 242 {
 243         struct snd_timer *timer;
 244         struct snd_timer_instance *timeri = NULL;
 245         struct device *card_dev_to_put = NULL;
 246         int err;
 247
 248         mutex_lock(&register_mutex);
 249         if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
 250                 /* open a slave instance */
 251                 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
 252                     tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
 253                         pr_debug("ALSA: timer: invalid slave class %i\n",
 254                                  tid->dev_sclass);
 255                         err = -EINVAL;
 256                         goto unlock;
 257                 }
 258                 if (num_slaves >= MAX_SLAVE_INSTANCES) {
 259                         err = -EBUSY;
 260                         goto unlock;
 261                 }
 262                 timeri = snd_timer_instance_new(owner, NULL);
 263                 if (!timeri) {
 264                         err = -ENOMEM;
 265                         goto unlock;
 266                 }
 267                 timeri->slave_class = tid->dev_sclass;
 268                 timeri->slave_id = tid->device;
 269                 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
 270                 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
 271                 num_slaves++;
 272                 err = snd_timer_check_slave(timeri);
 273                 if (err < 0) {
 274                         snd_timer_close_locked(timeri, &card_dev_to_put);
 275                         timeri = NULL;
 276                 }
 277                 goto unlock;
 278         }
 279
 280         /* open a master instance */
 281         timer = snd_timer_find(tid);
 282 #ifdef CONFIG_MODULES
 283         if (!timer) {
 284                 mutex_unlock(&register_mutex);
 285                 snd_timer_request(tid);
 286                 mutex_lock(&register_mutex);
 287                 timer = snd_timer_find(tid);
 288         }
 289 #endif
 290         if (!timer) {
 291                 err = -ENODEV;
 292                 goto unlock;
 293         }
 294         if (!list_empty(&timer->open_list_head)) {
 295                 struct snd_timer_instance *t =
 296                         list_entry(timer->open_list_head.next,
 297                                     struct snd_timer_instance, open_list);
 298                 if (t->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
 299                         err = -EBUSY;
 300                         goto unlock;
 301                 }
 302         }
 303         if (timer->num_instances >= timer->max_instances) {
 304                 err = -EBUSY;
 305                 goto unlock;
 306         }
 307         timeri = snd_timer_instance_new(owner, timer);
 308         if (!timeri) {
 309                 err = -ENOMEM;
 310                 goto unlock;
 311         }
 312         /* take a card refcount for safe disconnection */
 313         if (timer->card)
 314                 get_device(&timer->card->card_dev);
 315         timeri->slave_class = tid->dev_sclass;
 316         timeri->slave_id = slave_id;
 317
 318         if (list_empty(&timer->open_list_head) && timer->hw.open) {
 319                 err = timer->hw.open(timer);
 320                 if (err) {
 321                         kfree(timeri->owner);
 322                         kfree(timeri);
 323                         timeri = NULL;
 324
 325                         if (timer->card)
 326                                 card_dev_to_put = &timer->card->card_dev;
 327                         module_put(timer->module);
 328                         goto unlock;
 329                 }
 330         }
 331
 332         list_add_tail(&timeri->open_list, &timer->open_list_head);
 333         timer->num_instances++;
 334         err = snd_timer_check_master(timeri);
 335         if (err < 0) {
 336                 snd_timer_close_locked(timeri, &card_dev_to_put);
 337                 timeri = NULL;
 338         }
 339
 340  unlock:
 341         mutex_unlock(&register_mutex);
 342         /* put_device() is called after unlock for avoiding deadlock */
 343         if (card_dev_to_put)
 344                 put_device(card_dev_to_put);
 345         *ti = timeri;
 346         return err;
 347 }
 348 EXPORT_SYMBOL(snd_timer_open);
 349
 350 /*
 351  * close a timer instance
 352  * call this with register_mutex down.
 353  */
 354 static int snd_timer_close_locked(struct snd_timer_instance *timeri,
 355                                   struct device **card_devp_to_put)
 356 {
 357         struct snd_timer *timer = timeri->timer;
 358         struct snd_timer_instance *slave, *tmp;
 359
 360         if (timer) {
 361                 spin_lock_irq(&timer->lock);
 362                 timeri->flags |= SNDRV_TIMER_IFLG_DEAD;
 363                 spin_unlock_irq(&timer->lock);
 364         }
 365
 366         list_del(&timeri->open_list);
 367         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 368                 num_slaves--;
 369
 370         /* force to stop the timer */
 371         snd_timer_stop(timeri);
 372
 373         if (timer) {
 374                 timer->num_instances--;
 375                 /* wait, until the active callback is finished */
 376                 spin_lock_irq(&timer->lock);
 377                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 378                         spin_unlock_irq(&timer->lock);
 379                         udelay(10);
 380                         spin_lock_irq(&timer->lock);
 381                 }
 382                 spin_unlock_irq(&timer->lock);
 383
 384                 /* remove slave links */
 385                 spin_lock_irq(&slave_active_lock);
 386                 spin_lock(&timer->lock);
 387                 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
 388                                          open_list) {
 389                         list_move_tail(&slave->open_list, &snd_timer_slave_list);
 390                         timer->num_instances--;
 391                         slave->master = NULL;
 392                         slave->timer = NULL;
 393                         list_del_init(&slave->ack_list);
 394                         list_del_init(&slave->active_list);
 395                 }
 396                 spin_unlock(&timer->lock);
 397                 spin_unlock_irq(&slave_active_lock);
 398
 399                 /* slave doesn't need to release timer resources below */
 400                 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 401                         timer = NULL;
 402         }
 403
 404         if (timeri->private_free)
 405                 timeri->private_free(timeri);
 406         kfree(timeri->owner);
 407         kfree(timeri);
 408
 409         if (timer) {
 410                 if (list_empty(&timer->open_list_head) && timer->hw.close)
 411                         timer->hw.close(timer);
 412                 /* release a card refcount for safe disconnection */
 413                 if (timer->card)
 414                         *card_devp_to_put = &timer->card->card_dev;
 415                 module_put(timer->module);
 416         }
 417
 418         return 0;
 419 }
 420
 421 /*
 422  * close a timer instance
 423  */
 424 int snd_timer_close(struct snd_timer_instance *timeri)
 425 {
 426         struct device *card_dev_to_put = NULL;
 427         int err;
 428
 429         if (snd_BUG_ON(!timeri))
 430                 return -ENXIO;
 431
 432         mutex_lock(&register_mutex);
 433         err = snd_timer_close_locked(timeri, &card_dev_to_put);
 434         mutex_unlock(&register_mutex);
 435         /* put_device() is called after unlock for avoiding deadlock */
 436         if (card_dev_to_put)
 437                 put_device(card_dev_to_put);
 438         return err;
 439 }
 440 EXPORT_SYMBOL(snd_timer_close);
 441
 442 static unsigned long snd_timer_hw_resolution(struct snd_timer *timer)
 443 {
 444         if (timer->hw.c_resolution)
 445                 return timer->hw.c_resolution(timer);
 446         else
 447                 return timer->hw.resolution;
 448 }
 449
 450 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
 451 {
 452         struct snd_timer * timer;
 453         unsigned long ret = 0;
 454         unsigned long flags;
 455
 456         if (timeri == NULL)
 457                 return 0;
 458         timer = timeri->timer;
 459         if (timer) {
 460                 spin_lock_irqsave(&timer->lock, flags);
 461                 ret = snd_timer_hw_resolution(timer);
 462                 spin_unlock_irqrestore(&timer->lock, flags);
 463         }
 464         return ret;
 465 }
 466 EXPORT_SYMBOL(snd_timer_resolution);
 467
 468 static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
 469 {
 470         struct snd_timer *timer = ti->timer;
 471         unsigned long resolution = 0;
 472         struct snd_timer_instance *ts;
 473         struct timespec tstamp;
 474
 475         if (timer_tstamp_monotonic)
 476                 ktime_get_ts(&tstamp);
 477         else
 478                 getnstimeofday(&tstamp);
 479         if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
 480                        event > SNDRV_TIMER_EVENT_PAUSE))
 481                 return;
 482         if (timer &&
 483             (event == SNDRV_TIMER_EVENT_START ||
 484              event == SNDRV_TIMER_EVENT_CONTINUE))
 485                 resolution = snd_timer_hw_resolution(timer);
 486         if (ti->ccallback)
 487                 ti->ccallback(ti, event, &tstamp, resolution);
 488         if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
 489                 return;
 490         if (timer == NULL)
 491                 return;
 492         if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 493                 return;
 494         event += 10; /* convert to SNDRV_TIMER_EVENT_MXXX */
 495         list_for_each_entry(ts, &ti->slave_active_head, active_list)
 496                 if (ts->ccallback)
 497                         ts->ccallback(ts, event, &tstamp, resolution);
 498 }
 499
 500 /* start/continue a master timer */
 501 static int snd_timer_start1(struct snd_timer_instance *timeri,
 502                             bool start, unsigned long ticks)
 503 {
 504         struct snd_timer *timer;
 505         int result;
 506         unsigned long flags;
 507
 508         timer = timeri->timer;
 509         if (!timer)
 510                 return -EINVAL;
 511
 512         spin_lock_irqsave(&timer->lock, flags);
 513         if (timeri->flags & SNDRV_TIMER_IFLG_DEAD) {
 514                 result = -EINVAL;
 515                 goto unlock;
 516         }
 517         if (timer->card && timer->card->shutdown) {
 518                 result = -ENODEV;
 519                 goto unlock;
 520         }
 521         if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 522                              SNDRV_TIMER_IFLG_START)) {
 523                 result = -EBUSY;
 524                 goto unlock;
 525         }
 526
 527         if (start)
 528                 timeri->ticks = timeri->cticks = ticks;
 529         else if (!timeri->cticks)
 530                 timeri->cticks = 1;
 531         timeri->pticks = 0;
 532
 533         list_move_tail(&timeri->active_list, &timer->active_list_head);
 534         if (timer->running) {
 535                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 536                         goto __start_now;
 537                 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
 538                 timeri->flags |= SNDRV_TIMER_IFLG_START;
 539                 result = 1; /* delayed start */
 540         } else {
 541                 if (start)
 542                         timer->sticks = ticks;
 543                 timer->hw.start(timer);
 544               __start_now:
 545                 timer->running++;
 546                 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 547                 result = 0;
 548         }
 549         snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 550                           SNDRV_TIMER_EVENT_CONTINUE);
 551  unlock:
 552         spin_unlock_irqrestore(&timer->lock, flags);
 553         return result;
 554 }
 555
 556 /* start/continue a slave timer */
 557 static int snd_timer_start_slave(struct snd_timer_instance *timeri,
 558                                  bool start)
 559 {
 560         unsigned long flags;
 561         int err;
 562
 563         spin_lock_irqsave(&slave_active_lock, flags);
 564         if (timeri->flags & SNDRV_TIMER_IFLG_DEAD) {
 565                 err = -EINVAL;
 566                 goto unlock;
 567         }
 568         if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) {
 569                 err = -EBUSY;
 570                 goto unlock;
 571         }
 572         timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 573         if (timeri->master && timeri->timer) {
 574                 spin_lock(&timeri->timer->lock);
 575                 list_add_tail(&timeri->active_list,
 576                               &timeri->master->slave_active_head);
 577                 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 578                                   SNDRV_TIMER_EVENT_CONTINUE);
 579                 spin_unlock(&timeri->timer->lock);
 580         }
 581         err = 1; /* delayed start */
 582  unlock:
 583         spin_unlock_irqrestore(&slave_active_lock, flags);
 584         return err;
 585 }
 586
 587 /* stop/pause a master timer */
 588 static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
 589 {
 590         struct snd_timer *timer;
 591         int result = 0;
 592         unsigned long flags;
 593
 594         timer = timeri->timer;
 595         if (!timer)
 596                 return -EINVAL;
 597         spin_lock_irqsave(&timer->lock, flags);
 598         list_del_init(&timeri->ack_list);
 599         list_del_init(&timeri->active_list);
 600         if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 601                                SNDRV_TIMER_IFLG_START))) {
 602                 result = -EBUSY;
 603                 goto unlock;
 604         }
 605         if (timer->card && timer->card->shutdown)
 606                 goto unlock;
 607         if (stop) {
 608                 timeri->cticks = timeri->ticks;
 609                 timeri->pticks = 0;
 610         }
 611         if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
 612             !(--timer->running)) {
 613                 timer->hw.stop(timer);
 614                 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
 615                         timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 616                         snd_timer_reschedule(timer, 0);
 617                         if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
 618                                 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 619                                 timer->hw.start(timer);
 620                         }
 621                 }
 622         }
 623         timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
 624         if (stop)
 625                 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
 626         else
 627                 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
 628         snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 629                           SNDRV_TIMER_EVENT_PAUSE);
 630  unlock:
 631         spin_unlock_irqrestore(&timer->lock, flags);
 632         return result;
 633 }
 634
 635 /* stop/pause a slave timer */
 636 static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
 637 {
 638         unsigned long flags;
 639         bool running;
 640
 641         spin_lock_irqsave(&slave_active_lock, flags);
 642         running = timeri->flags & SNDRV_TIMER_IFLG_RUNNING;
 643         timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 644         if (timeri->timer) {
 645                 spin_lock(&timeri->timer->lock);
 646                 list_del_init(&timeri->ack_list);
 647                 list_del_init(&timeri->active_list);
 648                 if (running)
 649                         snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 650                                           SNDRV_TIMER_EVENT_PAUSE);
 651                 spin_unlock(&timeri->timer->lock);
 652         }
 653         spin_unlock_irqrestore(&slave_active_lock, flags);
 654         return running ? 0 : -EBUSY;
 655 }
 656
 657 /*
 658  *  start the timer instance
 659  */
 660 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
 661 {
 662         if (timeri == NULL || ticks < 1)
 663                 return -EINVAL;
 664         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 665                 return snd_timer_start_slave(timeri, true);
 666         else
 667                 return snd_timer_start1(timeri, true, ticks);
 668 }
 669 EXPORT_SYMBOL(snd_timer_start);
 670
 671 /*
 672  * stop the timer instance.
 673  *
 674  * do not call this from the timer callback!
 675  */
 676 int snd_timer_stop(struct snd_timer_instance *timeri)
 677 {
 678         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 679                 return snd_timer_stop_slave(timeri, true);
 680         else
 681                 return snd_timer_stop1(timeri, true);
 682 }
 683 EXPORT_SYMBOL(snd_timer_stop);
 684
 685 /*
 686  * start again..  the tick is kept.
 687  */
 688 int snd_timer_continue(struct snd_timer_instance *timeri)
 689 {
 690         /* timer can continue only after pause */
 691         if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
 692                 return -EINVAL;
 693
 694         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 695                 return snd_timer_start_slave(timeri, false);
 696         else
 697                 return snd_timer_start1(timeri, false, 0);
 698 }
 699 EXPORT_SYMBOL(snd_timer_continue);
 700
 701 /*
 702  * pause.. remember the ticks left
 703  */
 704 int snd_timer_pause(struct snd_timer_instance * timeri)
 705 {
 706         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 707                 return snd_timer_stop_slave(timeri, false);
 708         else
 709                 return snd_timer_stop1(timeri, false);
 710 }
 711 EXPORT_SYMBOL(snd_timer_pause);
 712
 713 /*
 714  * reschedule the timer
 715  *
 716  * start pending instances and check the scheduling ticks.
 717  * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
 718  */
 719 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
 720 {
 721         struct snd_timer_instance *ti;
 722         unsigned long ticks = ~0UL;
 723
 724         list_for_each_entry(ti, &timer->active_list_head, active_list) {
 725                 if (ti->flags & SNDRV_TIMER_IFLG_START) {
 726                         ti->flags &= ~SNDRV_TIMER_IFLG_START;
 727                         ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
 728                         timer->running++;
 729                 }
 730                 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
 731                         if (ticks > ti->cticks)
 732                                 ticks = ti->cticks;
 733                 }
 734         }
 735         if (ticks == ~0UL) {
 736                 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 737                 return;
 738         }
 739         if (ticks > timer->hw.ticks)
 740                 ticks = timer->hw.ticks;
 741         if (ticks_left != ticks)
 742                 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 743         timer->sticks = ticks;
 744 }
 745
 746 /* call callbacks in timer ack list */
 747 static void snd_timer_process_callbacks(struct snd_timer *timer,
 748                                         struct list_head *head)
 749 {
 750         struct snd_timer_instance *ti;
 751         unsigned long resolution, ticks;
 752
 753         while (!list_empty(head)) {
 754                 ti = list_first_entry(head, struct snd_timer_instance,
 755                                       ack_list);
 756
 757                 /* remove from ack_list and make empty */
 758                 list_del_init(&ti->ack_list);
 759
 760                 if (!(ti->flags & SNDRV_TIMER_IFLG_DEAD)) {
 761                         ticks = ti->pticks;
 762                         ti->pticks = 0;
 763                         resolution = ti->resolution;
 764                         ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 765                         spin_unlock(&timer->lock);
 766                         if (ti->callback)
 767                                 ti->callback(ti, resolution, ticks);
 768                         spin_lock(&timer->lock);
 769                         ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 770                 }
 771         }
 772 }
 773
 774 /* clear pending instances from ack list */
 775 static void snd_timer_clear_callbacks(struct snd_timer *timer,
 776                                       struct list_head *head)
 777 {
 778         unsigned long flags;
 779
 780         spin_lock_irqsave(&timer->lock, flags);
 781         while (!list_empty(head))
 782                 list_del_init(head->next);
 783         spin_unlock_irqrestore(&timer->lock, flags);
 784 }
 785
 786 /*
 787  * timer tasklet
 788  *
 789  */
 790 static void snd_timer_tasklet(unsigned long arg)
 791 {
 792         struct snd_timer *timer = (struct snd_timer *) arg;
 793         unsigned long flags;
 794
 795         if (timer->card && timer->card->shutdown) {
 796                 snd_timer_clear_callbacks(timer, &timer->sack_list_head);
 797                 return;
 798         }
 799
 800         spin_lock_irqsave(&timer->lock, flags);
 801         snd_timer_process_callbacks(timer, &timer->sack_list_head);
 802         spin_unlock_irqrestore(&timer->lock, flags);
 803 }
 804
 805 /*
 806  * timer interrupt
 807  *
 808  * ticks_left is usually equal to timer->sticks.
 809  *
 810  */
 811 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
 812 {
 813         struct snd_timer_instance *ti, *ts, *tmp;
 814         unsigned long resolution;
 815         struct list_head *ack_list_head;
 816         unsigned long flags;
 817         int use_tasklet = 0;
 818
 819         if (timer == NULL)
 820                 return;
 821
 822         if (timer->card && timer->card->shutdown) {
 823                 snd_timer_clear_callbacks(timer, &timer->ack_list_head);
 824                 return;
 825         }
 826
 827         spin_lock_irqsave(&timer->lock, flags);
 828
 829         /* remember the current resolution */
 830         resolution = snd_timer_hw_resolution(timer);
 831
 832         /* loop for all active instances
 833          * Here we cannot use list_for_each_entry because the active_list of a
 834          * processed instance is relinked to done_list_head before the callback
 835          * is called.
 836          */
 837         list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
 838                                  active_list) {
 839                 if (ti->flags & SNDRV_TIMER_IFLG_DEAD)
 840                         continue;
 841                 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
 842                         continue;
 843                 ti->pticks += ticks_left;
 844                 ti->resolution = resolution;
 845                 if (ti->cticks < ticks_left)
 846                         ti->cticks = 0;
 847                 else
 848                         ti->cticks -= ticks_left;
 849                 if (ti->cticks) /* not expired */
 850                         continue;
 851                 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
 852                         ti->cticks = ti->ticks;
 853                 } else {
 854                         ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 855                         --timer->running;
 856                         list_del_init(&ti->active_list);
 857                 }
 858                 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
 859                     (ti->flags & SNDRV_TIMER_IFLG_FAST))
 860                         ack_list_head = &timer->ack_list_head;
 861                 else
 862                         ack_list_head = &timer->sack_list_head;
 863                 if (list_empty(&ti->ack_list))
 864                         list_add_tail(&ti->ack_list, ack_list_head);
 865                 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
 866                         ts->pticks = ti->pticks;
 867                         ts->resolution = resolution;
 868                         if (list_empty(&ts->ack_list))
 869                                 list_add_tail(&ts->ack_list, ack_list_head);
 870                 }
 871         }
 872         if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
 873                 snd_timer_reschedule(timer, timer->sticks);
 874         if (timer->running) {
 875                 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
 876                         timer->hw.stop(timer);
 877                         timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 878                 }
 879                 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
 880                     (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
 881                         /* restart timer */
 882                         timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 883                         timer->hw.start(timer);
 884                 }
 885         } else {
 886                 timer->hw.stop(timer);
 887         }
 888
 889         /* now process all fast callbacks */
 890         snd_timer_process_callbacks(timer, &timer->ack_list_head);
 891
 892         /* do we have any slow callbacks? */
 893         use_tasklet = !list_empty(&timer->sack_list_head);
 894         spin_unlock_irqrestore(&timer->lock, flags);
 895
 896         if (use_tasklet)
 897                 tasklet_schedule(&timer->task_queue);
 898 }
 899 EXPORT_SYMBOL(snd_timer_interrupt);
 900
 901 /*
 902
 903  */
 904
 905 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
 906                   struct snd_timer **rtimer)
 907 {
 908         struct snd_timer *timer;
 909         int err;
 910         static struct snd_device_ops ops = {
 911                 .dev_free = snd_timer_dev_free,
 912                 .dev_register = snd_timer_dev_register,
 913                 .dev_disconnect = snd_timer_dev_disconnect,
 914         };
 915
 916         if (snd_BUG_ON(!tid))
 917                 return -EINVAL;
 918         if (tid->dev_class == SNDRV_TIMER_CLASS_CARD ||
 919             tid->dev_class == SNDRV_TIMER_CLASS_PCM) {
 920                 if (WARN_ON(!card))
 921                         return -EINVAL;
 922         }
 923         if (rtimer)
 924                 *rtimer = NULL;
 925         timer = kzalloc(sizeof(*timer), GFP_KERNEL);
 926         if (!timer)
 927                 return -ENOMEM;
 928         timer->tmr_class = tid->dev_class;
 929         timer->card = card;
 930         timer->tmr_device = tid->device;
 931         timer->tmr_subdevice = tid->subdevice;
 932         if (id)
 933                 strlcpy(timer->id, id, sizeof(timer->id));
 934         timer->sticks = 1;
 935         INIT_LIST_HEAD(&timer->device_list);
 936         INIT_LIST_HEAD(&timer->open_list_head);
 937         INIT_LIST_HEAD(&timer->active_list_head);
 938         INIT_LIST_HEAD(&timer->ack_list_head);
 939         INIT_LIST_HEAD(&timer->sack_list_head);
 940         spin_lock_init(&timer->lock);
 941         tasklet_init(&timer->task_queue, snd_timer_tasklet,
 942                      (unsigned long)timer);
 943         timer->max_instances = 1000; /* default limit per timer */
 944         if (card != NULL) {
 945                 timer->module = card->module;
 946                 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
 947                 if (err < 0) {
 948                         snd_timer_free(timer);
 949                         return err;
 950                 }
 951         }
 952         if (rtimer)
 953                 *rtimer = timer;
 954         return 0;
 955 }
 956 EXPORT_SYMBOL(snd_timer_new);
 957
 958 static int snd_timer_free(struct snd_timer *timer)
 959 {
 960         if (!timer)
 961                 return 0;
 962
 963         mutex_lock(&register_mutex);
 964         if (! list_empty(&timer->open_list_head)) {
 965                 struct list_head *p, *n;
 966                 struct snd_timer_instance *ti;
 967                 pr_warn("ALSA: timer %p is busy?\n", timer);
 968                 list_for_each_safe(p, n, &timer->open_list_head) {
 969                         list_del_init(p);
 970                         ti = list_entry(p, struct snd_timer_instance, open_list);
 971                         ti->timer = NULL;
 972                 }
 973         }
 974         list_del(&timer->device_list);
 975         mutex_unlock(&register_mutex);
 976
 977         if (timer->private_free)
 978                 timer->private_free(timer);
 979         kfree(timer);
 980         return 0;
 981 }
 982
 983 static int snd_timer_dev_free(struct snd_device *device)
 984 {
 985         struct snd_timer *timer = device->device_data;
 986         return snd_timer_free(timer);
 987 }
 988
 989 static int snd_timer_dev_register(struct snd_device *dev)
 990 {
 991         struct snd_timer *timer = dev->device_data;
 992         struct snd_timer *timer1;
 993
 994         if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
 995                 return -ENXIO;
 996         if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
 997             !timer->hw.resolution && timer->hw.c_resolution == NULL)
 998                 return -EINVAL;
 999
1000         mutex_lock(&register_mutex);
1001         list_for_each_entry(timer1, &snd_timer_list, device_list) {
1002                 if (timer1->tmr_class > timer->tmr_class)
1003                         break;
1004                 if (timer1->tmr_class < timer->tmr_class)
1005                         continue;
1006                 if (timer1->card && timer->card) {
1007                         if (timer1->card->number > timer->card->number)
1008                                 break;
1009                         if (timer1->card->number < timer->card->number)
1010                                 continue;
1011                 }
1012                 if (timer1->tmr_device > timer->tmr_device)
1013                         break;
1014                 if (timer1->tmr_device < timer->tmr_device)
1015                         continue;
1016                 if (timer1->tmr_subdevice > timer->tmr_subdevice)
1017                         break;
1018                 if (timer1->tmr_subdevice < timer->tmr_subdevice)
1019                         continue;
1020                 /* conflicts.. */
1021                 mutex_unlock(&register_mutex);
1022                 return -EBUSY;
1023         }
1024         list_add_tail(&timer->device_list, &timer1->device_list);
1025         mutex_unlock(&register_mutex);
1026         return 0;
1027 }
1028
1029 static int snd_timer_dev_disconnect(struct snd_device *device)
1030 {
1031         struct snd_timer *timer = device->device_data;
1032         struct snd_timer_instance *ti;
1033
1034         mutex_lock(&register_mutex);
1035         list_del_init(&timer->device_list);
1036         /* wake up pending sleepers */
1037         list_for_each_entry(ti, &timer->open_list_head, open_list) {
1038                 if (ti->disconnect)
1039                         ti->disconnect(ti);
1040         }
1041         mutex_unlock(&register_mutex);
1042         return 0;
1043 }
1044
1045 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
1046 {
1047         unsigned long flags;
1048         unsigned long resolution = 0;
1049         struct snd_timer_instance *ti, *ts;
1050
1051         if (timer->card && timer->card->shutdown)
1052                 return;
1053         if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
1054                 return;
1055         if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
1056                        event > SNDRV_TIMER_EVENT_MRESUME))
1057                 return;
1058         spin_lock_irqsave(&timer->lock, flags);
1059         if (event == SNDRV_TIMER_EVENT_MSTART ||
1060             event == SNDRV_TIMER_EVENT_MCONTINUE ||
1061             event == SNDRV_TIMER_EVENT_MRESUME)
1062                 resolution = snd_timer_hw_resolution(timer);
1063         list_for_each_entry(ti, &timer->active_list_head, active_list) {
1064                 if (ti->ccallback)
1065                         ti->ccallback(ti, event, tstamp, resolution);
1066                 list_for_each_entry(ts, &ti->slave_active_head, active_list)
1067                         if (ts->ccallback)
1068                                 ts->ccallback(ts, event, tstamp, resolution);
1069         }
1070         spin_unlock_irqrestore(&timer->lock, flags);
1071 }
1072 EXPORT_SYMBOL(snd_timer_notify);
1073
1074 /*
1075  * exported functions for global timers
1076  */
1077 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
1078 {
1079         struct snd_timer_id tid;
1080
1081         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
1082         tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1083         tid.card = -1;
1084         tid.device = device;
1085         tid.subdevice = 0;
1086         return snd_timer_new(NULL, id, &tid, rtimer);
1087 }
1088 EXPORT_SYMBOL(snd_timer_global_new);
1089
1090 int snd_timer_global_free(struct snd_timer *timer)
1091 {
1092         return snd_timer_free(timer);
1093 }
1094 EXPORT_SYMBOL(snd_timer_global_free);
1095
1096 int snd_timer_global_register(struct snd_timer *timer)
1097 {
1098         struct snd_device dev;
1099
1100         memset(&dev, 0, sizeof(dev));
1101         dev.device_data = timer;
1102         return snd_timer_dev_register(&dev);
1103 }
1104 EXPORT_SYMBOL(snd_timer_global_register);
1105
1106 /*
1107  *  System timer
1108  */
1109
1110 struct snd_timer_system_private {
1111         struct timer_list tlist;
1112         struct snd_timer *snd_timer;
1113         unsigned long last_expires;
1114         unsigned long last_jiffies;
1115         unsigned long correction;
1116 };
1117
1118 static void snd_timer_s_function(struct timer_list *t)
1119 {
1120         struct snd_timer_system_private *priv = from_timer(priv, t,
1121                                                                 tlist);
1122         struct snd_timer *timer = priv->snd_timer;
1123         unsigned long jiff = jiffies;
1124         if (time_after(jiff, priv->last_expires))
1125                 priv->correction += (long)jiff - (long)priv->last_expires;
1126         snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1127 }
1128
1129 static int snd_timer_s_start(struct snd_timer * timer)
1130 {
1131         struct snd_timer_system_private *priv;
1132         unsigned long njiff;
1133
1134         priv = (struct snd_timer_system_private *) timer->private_data;
1135         njiff = (priv->last_jiffies = jiffies);
1136         if (priv->correction > timer->sticks - 1) {
1137                 priv->correction -= timer->sticks - 1;
1138                 njiff++;
1139         } else {
1140                 njiff += timer->sticks - priv->correction;
1141                 priv->correction = 0;
1142         }
1143         priv->last_expires = njiff;
1144         mod_timer(&priv->tlist, njiff);
1145         return 0;
1146 }
1147
1148 static int snd_timer_s_stop(struct snd_timer * timer)
1149 {
1150         struct snd_timer_system_private *priv;
1151         unsigned long jiff;
1152
1153         priv = (struct snd_timer_system_private *) timer->private_data;
1154         del_timer(&priv->tlist);
1155         jiff = jiffies;
1156         if (time_before(jiff, priv->last_expires))
1157                 timer->sticks = priv->last_expires - jiff;
1158         else
1159                 timer->sticks = 1;
1160         priv->correction = 0;
1161         return 0;
1162 }
1163
1164 static int snd_timer_s_close(struct snd_timer *timer)
1165 {
1166         struct snd_timer_system_private *priv;
1167
1168         priv = (struct snd_timer_system_private *)timer->private_data;
1169         del_timer_sync(&priv->tlist);
1170         return 0;
1171 }
1172
1173 static struct snd_timer_hardware snd_timer_system =
1174 {
1175         .flags =        SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
1176         .resolution =   1000000000L / HZ,
1177         .ticks =        10000000L,
1178         .close =        snd_timer_s_close,
1179         .start =        snd_timer_s_start,
1180         .stop =         snd_timer_s_stop
1181 };
1182
1183 static void snd_timer_free_system(struct snd_timer *timer)
1184 {
1185         kfree(timer->private_data);
1186 }
1187
1188 static int snd_timer_register_system(void)
1189 {
1190         struct snd_timer *timer;
1191         struct snd_timer_system_private *priv;
1192         int err;
1193
1194         err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1195         if (err < 0)
1196                 return err;
1197         strcpy(timer->name, "system timer");
1198         timer->hw = snd_timer_system;
1199         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1200         if (priv == NULL) {
1201                 snd_timer_free(timer);
1202                 return -ENOMEM;
1203         }
1204         priv->snd_timer = timer;
1205         timer_setup(&priv->tlist, snd_timer_s_function, 0);
1206         timer->private_data = priv;
1207         timer->private_free = snd_timer_free_system;
1208         return snd_timer_global_register(timer);
1209 }
1210
1211 #ifdef CONFIG_SND_PROC_FS
1212 /*
1213  *  Info interface
1214  */
1215
1216 static void snd_timer_proc_read(struct snd_info_entry *entry,
1217                                 struct snd_info_buffer *buffer)
1218 {
1219         struct snd_timer *timer;
1220         struct snd_timer_instance *ti;
1221
1222         mutex_lock(&register_mutex);
1223         list_for_each_entry(timer, &snd_timer_list, device_list) {
1224                 if (timer->card && timer->card->shutdown)
1225                         continue;
1226                 switch (timer->tmr_class) {
1227                 case SNDRV_TIMER_CLASS_GLOBAL:
1228                         snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1229                         break;
1230                 case SNDRV_TIMER_CLASS_CARD:
1231                         snd_iprintf(buffer, "C%i-%i: ",
1232                                     timer->card->number, timer->tmr_device);
1233                         break;
1234                 case SNDRV_TIMER_CLASS_PCM:
1235                         snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1236                                     timer->tmr_device, timer->tmr_subdevice);
1237                         break;
1238                 default:
1239                         snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1240                                     timer->card ? timer->card->number : -1,
1241                                     timer->tmr_device, timer->tmr_subdevice);
1242                 }
1243                 snd_iprintf(buffer, "%s :", timer->name);
1244                 if (timer->hw.resolution)
1245                         snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1246                                     timer->hw.resolution / 1000,
1247                                     timer->hw.resolution % 1000,
1248                                     timer->hw.ticks);
1249                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1250                         snd_iprintf(buffer, " SLAVE");
1251                 snd_iprintf(buffer, "\n");
1252                 list_for_each_entry(ti, &timer->open_list_head, open_list)
1253                         snd_iprintf(buffer, "  Client %s : %s\n",
1254                                     ti->owner ? ti->owner : "unknown",
1255                                     ti->flags & (SNDRV_TIMER_IFLG_START |
1256                                                  SNDRV_TIMER_IFLG_RUNNING)
1257                                     ? "running" : "stopped");
1258         }
1259         mutex_unlock(&register_mutex);
1260 }
1261
1262 static struct snd_info_entry *snd_timer_proc_entry;
1263
1264 static void __init snd_timer_proc_init(void)
1265 {
1266         struct snd_info_entry *entry;
1267
1268         entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1269         if (entry != NULL) {
1270                 entry->c.text.read = snd_timer_proc_read;
1271                 if (snd_info_register(entry) < 0) {
1272                         snd_info_free_entry(entry);
1273                         entry = NULL;
1274                 }
1275         }
1276         snd_timer_proc_entry = entry;
1277 }
1278
1279 static void __exit snd_timer_proc_done(void)
1280 {
1281         snd_info_free_entry(snd_timer_proc_entry);
1282 }
1283 #else /* !CONFIG_SND_PROC_FS */
1284 #define snd_timer_proc_init()
1285 #define snd_timer_proc_done()
1286 #endif
1287
1288 /*
1289  *  USER SPACE interface
1290  */
1291
1292 static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1293                                      unsigned long resolution,
1294                                      unsigned long ticks)
1295 {
1296         struct snd_timer_user *tu = timeri->callback_data;
1297         struct snd_timer_read *r;
1298         int prev;
1299
1300         spin_lock(&tu->qlock);
1301         if (tu->qused > 0) {
1302                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1303                 r = &tu->queue[prev];
1304                 if (r->resolution == resolution) {
1305                         r->ticks += ticks;
1306                         goto __wake;
1307                 }
1308         }
1309         if (tu->qused >= tu->queue_size) {
1310                 tu->overrun++;
1311         } else {
1312                 r = &tu->queue[tu->qtail++];
1313                 tu->qtail %= tu->queue_size;
1314                 r->resolution = resolution;
1315                 r->ticks = ticks;
1316                 tu->qused++;
1317         }
1318       __wake:
1319         spin_unlock(&tu->qlock);
1320         snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1321         wake_up(&tu->qchange_sleep);
1322 }
1323
1324 static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1325                                             struct snd_timer_tread *tread)
1326 {
1327         if (tu->qused >= tu->queue_size) {
1328                 tu->overrun++;
1329         } else {
1330                 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1331                 tu->qtail %= tu->queue_size;
1332                 tu->qused++;
1333         }
1334 }
1335
1336 static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1337                                      int event,
1338                                      struct timespec *tstamp,
1339                                      unsigned long resolution)
1340 {
1341         struct snd_timer_user *tu = timeri->callback_data;
1342         struct snd_timer_tread r1;
1343         unsigned long flags;
1344
1345         if (event >= SNDRV_TIMER_EVENT_START &&
1346             event <= SNDRV_TIMER_EVENT_PAUSE)
1347                 tu->tstamp = *tstamp;
1348         if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1349                 return;
1350         memset(&r1, 0, sizeof(r1));
1351         r1.event = event;
1352         r1.tstamp = *tstamp;
1353         r1.val = resolution;
1354         spin_lock_irqsave(&tu->qlock, flags);
1355         snd_timer_user_append_to_tqueue(tu, &r1);
1356         spin_unlock_irqrestore(&tu->qlock, flags);
1357         snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1358         wake_up(&tu->qchange_sleep);
1359 }
1360
1361 static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1362 {
1363         struct snd_timer_user *tu = timeri->callback_data;
1364
1365         tu->disconnected = true;
1366         wake_up(&tu->qchange_sleep);
1367 }
1368
1369 static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1370                                       unsigned long resolution,
1371                                       unsigned long ticks)
1372 {
1373         struct snd_timer_user *tu = timeri->callback_data;
1374         struct snd_timer_tread *r, r1;
1375         struct timespec tstamp;
1376         int prev, append = 0;
1377
1378         memset(&r1, 0, sizeof(r1));
1379         memset(&tstamp, 0, sizeof(tstamp));
1380         spin_lock(&tu->qlock);
1381         if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1382                            (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1383                 spin_unlock(&tu->qlock);
1384                 return;
1385         }
1386         if (tu->last_resolution != resolution || ticks > 0) {
1387                 if (timer_tstamp_monotonic)
1388                         ktime_get_ts(&tstamp);
1389                 else
1390                         getnstimeofday(&tstamp);
1391         }
1392         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1393             tu->last_resolution != resolution) {
1394                 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1395                 r1.tstamp = tstamp;
1396                 r1.val = resolution;
1397                 snd_timer_user_append_to_tqueue(tu, &r1);
1398                 tu->last_resolution = resolution;
1399                 append++;
1400         }
1401         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1402                 goto __wake;
1403         if (ticks == 0)
1404                 goto __wake;
1405         if (tu->qused > 0) {
1406                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1407                 r = &tu->tqueue[prev];
1408                 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1409                         r->tstamp = tstamp;
1410                         r->val += ticks;
1411                         append++;
1412                         goto __wake;
1413                 }
1414         }
1415         r1.event = SNDRV_TIMER_EVENT_TICK;
1416         r1.tstamp = tstamp;
1417         r1.val = ticks;
1418         snd_timer_user_append_to_tqueue(tu, &r1);
1419         append++;
1420       __wake:
1421         spin_unlock(&tu->qlock);
1422         if (append == 0)
1423                 return;
1424         snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1425         wake_up(&tu->qchange_sleep);
1426 }
1427
1428 static int realloc_user_queue(struct snd_timer_user *tu, int size)
1429 {
1430         struct snd_timer_read *queue = NULL;
1431         struct snd_timer_tread *tqueue = NULL;
1432
1433         if (tu->tread) {
1434                 tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL);
1435                 if (!tqueue)
1436                         return -ENOMEM;
1437         } else {
1438                 queue = kcalloc(size, sizeof(*queue), GFP_KERNEL);
1439                 if (!queue)
1440                         return -ENOMEM;
1441         }
1442
1443         spin_lock_irq(&tu->qlock);
1444         kfree(tu->queue);
1445         kfree(tu->tqueue);
1446         tu->queue_size = size;
1447         tu->queue = queue;
1448         tu->tqueue = tqueue;
1449         tu->qhead = tu->qtail = tu->qused = 0;
1450         spin_unlock_irq(&tu->qlock);
1451
1452         return 0;
1453 }
1454
1455 static int snd_timer_user_open(struct inode *inode, struct file *file)
1456 {
1457         struct snd_timer_user *tu;
1458         int err;
1459
1460         err = stream_open(inode, file);
1461         if (err < 0)
1462                 return err;
1463
1464         tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1465         if (tu == NULL)
1466                 return -ENOMEM;
1467         spin_lock_init(&tu->qlock);
1468         init_waitqueue_head(&tu->qchange_sleep);
1469         mutex_init(&tu->ioctl_lock);
1470         tu->ticks = 1;
1471         if (realloc_user_queue(tu, 128) < 0) {
1472                 kfree(tu);
1473                 return -ENOMEM;
1474         }
1475         file->private_data = tu;
1476         return 0;
1477 }
1478
1479 static int snd_timer_user_release(struct inode *inode, struct file *file)
1480 {
1481         struct snd_timer_user *tu;
1482
1483         if (file->private_data) {
1484                 tu = file->private_data;
1485                 file->private_data = NULL;
1486                 mutex_lock(&tu->ioctl_lock);
1487                 if (tu->timeri)
1488                         snd_timer_close(tu->timeri);
1489                 mutex_unlock(&tu->ioctl_lock);
1490                 snd_fasync_free(tu->fasync);
1491                 kfree(tu->queue);
1492                 kfree(tu->tqueue);
1493                 kfree(tu);
1494         }
1495         return 0;
1496 }
1497
1498 static void snd_timer_user_zero_id(struct snd_timer_id *id)
1499 {
1500         id->dev_class = SNDRV_TIMER_CLASS_NONE;
1501         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1502         id->card = -1;
1503         id->device = -1;
1504         id->subdevice = -1;
1505 }
1506
1507 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1508 {
1509         id->dev_class = timer->tmr_class;
1510         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1511         id->card = timer->card ? timer->card->number : -1;
1512         id->device = timer->tmr_device;
1513         id->subdevice = timer->tmr_subdevice;
1514 }
1515
1516 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1517 {
1518         struct snd_timer_id id;
1519         struct snd_timer *timer;
1520         struct list_head *p;
1521
1522         if (copy_from_user(&id, _tid, sizeof(id)))
1523                 return -EFAULT;
1524         mutex_lock(&register_mutex);
1525         if (id.dev_class < 0) {         /* first item */
1526                 if (list_empty(&snd_timer_list))
1527                         snd_timer_user_zero_id(&id);
1528                 else {
1529                         timer = list_entry(snd_timer_list.next,
1530                                            struct snd_timer, device_list);
1531                         snd_timer_user_copy_id(&id, timer);
1532                 }
1533         } else {
1534                 switch (id.dev_class) {
1535                 case SNDRV_TIMER_CLASS_GLOBAL:
1536                         id.device = id.device < 0 ? 0 : id.device + 1;
1537                         list_for_each(p, &snd_timer_list) {
1538                                 timer = list_entry(p, struct snd_timer, device_list);
1539                                 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1540                                         snd_timer_user_copy_id(&id, timer);
1541                                         break;
1542                                 }
1543                                 if (timer->tmr_device >= id.device) {
1544                                         snd_timer_user_copy_id(&id, timer);
1545                                         break;
1546                                 }
1547                         }
1548                         if (p == &snd_timer_list)
1549                                 snd_timer_user_zero_id(&id);
1550                         break;
1551                 case SNDRV_TIMER_CLASS_CARD:
1552                 case SNDRV_TIMER_CLASS_PCM:
1553                         if (id.card < 0) {
1554                                 id.card = 0;
1555                         } else {
1556                                 if (id.device < 0) {
1557                                         id.device = 0;
1558                                 } else {
1559                                         if (id.subdevice < 0)
1560                                                 id.subdevice = 0;
1561                                         else if (id.subdevice < INT_MAX)
1562                                                 id.subdevice++;
1563                                 }
1564                         }
1565                         list_for_each(p, &snd_timer_list) {
1566                                 timer = list_entry(p, struct snd_timer, device_list);
1567                                 if (timer->tmr_class > id.dev_class) {
1568                                         snd_timer_user_copy_id(&id, timer);
1569                                         break;
1570                                 }
1571                                 if (timer->tmr_class < id.dev_class)
1572                                         continue;
1573                                 if (timer->card->number > id.card) {
1574                                         snd_timer_user_copy_id(&id, timer);
1575                                         break;
1576                                 }
1577                                 if (timer->card->number < id.card)
1578                                         continue;
1579                                 if (timer->tmr_device > id.device) {
1580                                         snd_timer_user_copy_id(&id, timer);
1581                                         break;
1582                                 }
1583                                 if (timer->tmr_device < id.device)
1584                                         continue;
1585                                 if (timer->tmr_subdevice > id.subdevice) {
1586                                         snd_timer_user_copy_id(&id, timer);
1587                                         break;
1588                                 }
1589                                 if (timer->tmr_subdevice < id.subdevice)
1590                                         continue;
1591                                 snd_timer_user_copy_id(&id, timer);
1592                                 break;
1593                         }
1594                         if (p == &snd_timer_list)
1595                                 snd_timer_user_zero_id(&id);
1596                         break;
1597                 default:
1598                         snd_timer_user_zero_id(&id);
1599                 }
1600         }
1601         mutex_unlock(&register_mutex);
1602         if (copy_to_user(_tid, &id, sizeof(*_tid)))
1603                 return -EFAULT;
1604         return 0;
1605 }
1606
1607 static int snd_timer_user_ginfo(struct file *file,
1608                                 struct snd_timer_ginfo __user *_ginfo)
1609 {
1610         struct snd_timer_ginfo *ginfo;
1611         struct snd_timer_id tid;
1612         struct snd_timer *t;
1613         struct list_head *p;
1614         int err = 0;
1615
1616         ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1617         if (IS_ERR(ginfo))
1618                 return PTR_ERR(ginfo);
1619
1620         tid = ginfo->tid;
1621         memset(ginfo, 0, sizeof(*ginfo));
1622         ginfo->tid = tid;
1623         mutex_lock(&register_mutex);
1624         t = snd_timer_find(&tid);
1625         if (t != NULL) {
1626                 ginfo->card = t->card ? t->card->number : -1;
1627                 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1628                         ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1629                 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1630                 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1631                 ginfo->resolution = t->hw.resolution;
1632                 if (t->hw.resolution_min > 0) {
1633                         ginfo->resolution_min = t->hw.resolution_min;
1634                         ginfo->resolution_max = t->hw.resolution_max;
1635                 }
1636                 list_for_each(p, &t->open_list_head) {
1637                         ginfo->clients++;
1638                 }
1639         } else {
1640                 err = -ENODEV;
1641         }
1642         mutex_unlock(&register_mutex);
1643         if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1644                 err = -EFAULT;
1645         kfree(ginfo);
1646         return err;
1647 }
1648
1649 static int timer_set_gparams(struct snd_timer_gparams *gparams)
1650 {
1651         struct snd_timer *t;
1652         int err;
1653
1654         mutex_lock(&register_mutex);
1655         t = snd_timer_find(&gparams->tid);
1656         if (!t) {
1657                 err = -ENODEV;
1658                 goto _error;
1659         }
1660         if (!list_empty(&t->open_list_head)) {
1661                 err = -EBUSY;
1662                 goto _error;
1663         }
1664         if (!t->hw.set_period) {
1665                 err = -ENOSYS;
1666                 goto _error;
1667         }
1668         err = t->hw.set_period(t, gparams->period_num, gparams->period_den);
1669 _error:
1670         mutex_unlock(&register_mutex);
1671         return err;
1672 }
1673
1674 static int snd_timer_user_gparams(struct file *file,
1675                                   struct snd_timer_gparams __user *_gparams)
1676 {
1677         struct snd_timer_gparams gparams;
1678
1679         if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1680                 return -EFAULT;
1681         return timer_set_gparams(&gparams);
1682 }
1683
1684 static int snd_timer_user_gstatus(struct file *file,
1685                                   struct snd_timer_gstatus __user *_gstatus)
1686 {
1687         struct snd_timer_gstatus gstatus;
1688         struct snd_timer_id tid;
1689         struct snd_timer *t;
1690         int err = 0;
1691
1692         if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1693                 return -EFAULT;
1694         tid = gstatus.tid;
1695         memset(&gstatus, 0, sizeof(gstatus));
1696         gstatus.tid = tid;
1697         mutex_lock(&register_mutex);
1698         t = snd_timer_find(&tid);
1699         if (t != NULL) {
1700                 spin_lock_irq(&t->lock);
1701                 gstatus.resolution = snd_timer_hw_resolution(t);
1702                 if (t->hw.precise_resolution) {
1703                         t->hw.precise_resolution(t, &gstatus.resolution_num,
1704                                                  &gstatus.resolution_den);
1705                 } else {
1706                         gstatus.resolution_num = gstatus.resolution;
1707                         gstatus.resolution_den = 1000000000uL;
1708                 }
1709                 spin_unlock_irq(&t->lock);
1710         } else {
1711                 err = -ENODEV;
1712         }
1713         mutex_unlock(&register_mutex);
1714         if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1715                 err = -EFAULT;
1716         return err;
1717 }
1718
1719 static int snd_timer_user_tselect(struct file *file,
1720                                   struct snd_timer_select __user *_tselect)
1721 {
1722         struct snd_timer_user *tu;
1723         struct snd_timer_select tselect;
1724         char str[32];
1725         int err = 0;
1726
1727         tu = file->private_data;
1728         if (tu->timeri) {
1729                 snd_timer_close(tu->timeri);
1730                 tu->timeri = NULL;
1731         }
1732         if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1733                 err = -EFAULT;
1734                 goto __err;
1735         }
1736         sprintf(str, "application %i", current->pid);
1737         if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1738                 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1739         err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1740         if (err < 0)
1741                 goto __err;
1742
1743         tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1744         tu->timeri->callback = tu->tread
1745                         ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1746         tu->timeri->ccallback = snd_timer_user_ccallback;
1747         tu->timeri->callback_data = (void *)tu;
1748         tu->timeri->disconnect = snd_timer_user_disconnect;
1749
1750       __err:
1751         return err;
1752 }
1753
1754 static int snd_timer_user_info(struct file *file,
1755                                struct snd_timer_info __user *_info)
1756 {
1757         struct snd_timer_user *tu;
1758         struct snd_timer_info *info;
1759         struct snd_timer *t;
1760         int err = 0;
1761
1762         tu = file->private_data;
1763         if (!tu->timeri)
1764                 return -EBADFD;
1765         t = tu->timeri->timer;
1766         if (!t)
1767                 return -EBADFD;
1768
1769         info = kzalloc(sizeof(*info), GFP_KERNEL);
1770         if (! info)
1771                 return -ENOMEM;
1772         info->card = t->card ? t->card->number : -1;
1773         if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1774                 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1775         strlcpy(info->id, t->id, sizeof(info->id));
1776         strlcpy(info->name, t->name, sizeof(info->name));
1777         info->resolution = t->hw.resolution;
1778         if (copy_to_user(_info, info, sizeof(*_info)))
1779                 err = -EFAULT;
1780         kfree(info);
1781         return err;
1782 }
1783
1784 static int snd_timer_user_params(struct file *file,
1785                                  struct snd_timer_params __user *_params)
1786 {
1787         struct snd_timer_user *tu;
1788         struct snd_timer_params params;
1789         struct snd_timer *t;
1790         int err;
1791
1792         tu = file->private_data;
1793         if (!tu->timeri)
1794                 return -EBADFD;
1795         t = tu->timeri->timer;
1796         if (!t)
1797                 return -EBADFD;
1798         if (copy_from_user(&params, _params, sizeof(params)))
1799                 return -EFAULT;
1800         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1801                 u64 resolution;
1802
1803                 if (params.ticks < 1) {
1804                         err = -EINVAL;
1805                         goto _end;
1806                 }
1807
1808                 /* Don't allow resolution less than 1ms */
1809                 resolution = snd_timer_resolution(tu->timeri);
1810                 resolution *= params.ticks;
1811                 if (resolution < 1000000) {
1812                         err = -EINVAL;
1813                         goto _end;
1814                 }
1815         }
1816         if (params.queue_size > 0 &&
1817             (params.queue_size < 32 || params.queue_size > 1024)) {
1818                 err = -EINVAL;
1819                 goto _end;
1820         }
1821         if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1822                               (1<<SNDRV_TIMER_EVENT_TICK)|
1823                               (1<<SNDRV_TIMER_EVENT_START)|
1824                               (1<<SNDRV_TIMER_EVENT_STOP)|
1825                               (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1826                               (1<<SNDRV_TIMER_EVENT_PAUSE)|
1827                               (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1828                               (1<<SNDRV_TIMER_EVENT_RESUME)|
1829                               (1<<SNDRV_TIMER_EVENT_MSTART)|
1830                               (1<<SNDRV_TIMER_EVENT_MSTOP)|
1831                               (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1832                               (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1833                               (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1834                               (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1835                 err = -EINVAL;
1836                 goto _end;
1837         }
1838         snd_timer_stop(tu->timeri);
1839         spin_lock_irq(&t->lock);
1840         tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1841                                SNDRV_TIMER_IFLG_EXCLUSIVE|
1842                                SNDRV_TIMER_IFLG_EARLY_EVENT);
1843         if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1844                 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1845         if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1846                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1847         if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1848                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1849         spin_unlock_irq(&t->lock);
1850         if (params.queue_size > 0 &&
1851             (unsigned int)tu->queue_size != params.queue_size) {
1852                 err = realloc_user_queue(tu, params.queue_size);
1853                 if (err < 0)
1854                         goto _end;
1855         }
1856         spin_lock_irq(&tu->qlock);
1857         tu->qhead = tu->qtail = tu->qused = 0;
1858         if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1859                 if (tu->tread) {
1860                         struct snd_timer_tread tread;
1861                         memset(&tread, 0, sizeof(tread));
1862                         tread.event = SNDRV_TIMER_EVENT_EARLY;
1863                         tread.tstamp.tv_sec = 0;
1864                         tread.tstamp.tv_nsec = 0;
1865                         tread.val = 0;
1866                         snd_timer_user_append_to_tqueue(tu, &tread);
1867                 } else {
1868                         struct snd_timer_read *r = &tu->queue[0];
1869                         r->resolution = 0;
1870                         r->ticks = 0;
1871                         tu->qused++;
1872                         tu->qtail++;
1873                 }
1874         }
1875         tu->filter = params.filter;
1876         tu->ticks = params.ticks;
1877         spin_unlock_irq(&tu->qlock);
1878         err = 0;
1879  _end:
1880         if (copy_to_user(_params, &params, sizeof(params)))
1881                 return -EFAULT;
1882         return err;
1883 }
1884
1885 static int snd_timer_user_status(struct file *file,
1886                                  struct snd_timer_status __user *_status)
1887 {
1888         struct snd_timer_user *tu;
1889         struct snd_timer_status status;
1890
1891         tu = file->private_data;
1892         if (!tu->timeri)
1893                 return -EBADFD;
1894         memset(&status, 0, sizeof(status));
1895         status.tstamp = tu->tstamp;
1896         status.resolution = snd_timer_resolution(tu->timeri);
1897         status.lost = tu->timeri->lost;
1898         status.overrun = tu->overrun;
1899         spin_lock_irq(&tu->qlock);
1900         status.queue = tu->qused;
1901         spin_unlock_irq(&tu->qlock);
1902         if (copy_to_user(_status, &status, sizeof(status)))
1903                 return -EFAULT;
1904         return 0;
1905 }
1906
1907 static int snd_timer_user_start(struct file *file)
1908 {
1909         int err;
1910         struct snd_timer_user *tu;
1911
1912         tu = file->private_data;
1913         if (!tu->timeri)
1914                 return -EBADFD;
1915         snd_timer_stop(tu->timeri);
1916         tu->timeri->lost = 0;
1917         tu->last_resolution = 0;
1918         err = snd_timer_start(tu->timeri, tu->ticks);
1919         if (err < 0)
1920                 return err;
1921         return 0;
1922 }
1923
1924 static int snd_timer_user_stop(struct file *file)
1925 {
1926         int err;
1927         struct snd_timer_user *tu;
1928
1929         tu = file->private_data;
1930         if (!tu->timeri)
1931                 return -EBADFD;
1932         err = snd_timer_stop(tu->timeri);
1933         if (err < 0)
1934                 return err;
1935         return 0;
1936 }
1937
1938 static int snd_timer_user_continue(struct file *file)
1939 {
1940         int err;
1941         struct snd_timer_user *tu;
1942
1943         tu = file->private_data;
1944         if (!tu->timeri)
1945                 return -EBADFD;
1946         /* start timer instead of continue if it's not used before */
1947         if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
1948                 return snd_timer_user_start(file);
1949         tu->timeri->lost = 0;
1950         err = snd_timer_continue(tu->timeri);
1951         if (err < 0)
1952                 return err;
1953         return 0;
1954 }
1955
1956 static int snd_timer_user_pause(struct file *file)
1957 {
1958         int err;
1959         struct snd_timer_user *tu;
1960
1961         tu = file->private_data;
1962         if (!tu->timeri)
1963                 return -EBADFD;
1964         err = snd_timer_pause(tu->timeri);
1965         if (err < 0)
1966                 return err;
1967         return 0;
1968 }
1969
1970 enum {
1971         SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1972         SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1973         SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1974         SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1975 };
1976
1977 static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1978                                  unsigned long arg)
1979 {
1980         struct snd_timer_user *tu;
1981         void __user *argp = (void __user *)arg;
1982         int __user *p = argp;
1983
1984         tu = file->private_data;
1985         switch (cmd) {
1986         case SNDRV_TIMER_IOCTL_PVERSION:
1987                 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1988         case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1989                 return snd_timer_user_next_device(argp);
1990         case SNDRV_TIMER_IOCTL_TREAD:
1991         {
1992                 int xarg, old_tread;
1993
1994                 if (tu->timeri) /* too late */
1995                         return -EBUSY;
1996                 if (get_user(xarg, p))
1997                         return -EFAULT;
1998                 old_tread = tu->tread;
1999                 tu->tread = xarg ? 1 : 0;
2000                 if (tu->tread != old_tread &&
2001                     realloc_user_queue(tu, tu->queue_size) < 0) {
2002                         tu->tread = old_tread;
2003                         return -ENOMEM;
2004                 }
2005                 return 0;
2006         }
2007         case SNDRV_TIMER_IOCTL_GINFO:
2008                 return snd_timer_user_ginfo(file, argp);
2009         case SNDRV_TIMER_IOCTL_GPARAMS:
2010                 return snd_timer_user_gparams(file, argp);
2011         case SNDRV_TIMER_IOCTL_GSTATUS:
2012                 return snd_timer_user_gstatus(file, argp);
2013         case SNDRV_TIMER_IOCTL_SELECT:
2014                 return snd_timer_user_tselect(file, argp);
2015         case SNDRV_TIMER_IOCTL_INFO:
2016                 return snd_timer_user_info(file, argp);
2017         case SNDRV_TIMER_IOCTL_PARAMS:
2018                 return snd_timer_user_params(file, argp);
2019         case SNDRV_TIMER_IOCTL_STATUS:
2020                 return snd_timer_user_status(file, argp);
2021         case SNDRV_TIMER_IOCTL_START:
2022         case SNDRV_TIMER_IOCTL_START_OLD:
2023                 return snd_timer_user_start(file);
2024         case SNDRV_TIMER_IOCTL_STOP:
2025         case SNDRV_TIMER_IOCTL_STOP_OLD:
2026                 return snd_timer_user_stop(file);
2027         case SNDRV_TIMER_IOCTL_CONTINUE:
2028         case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
2029                 return snd_timer_user_continue(file);
2030         case SNDRV_TIMER_IOCTL_PAUSE:
2031         case SNDRV_TIMER_IOCTL_PAUSE_OLD:
2032                 return snd_timer_user_pause(file);
2033         }
2034         return -ENOTTY;
2035 }
2036
2037 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2038                                  unsigned long arg)
2039 {
2040         struct snd_timer_user *tu = file->private_data;
2041         long ret;
2042
2043         mutex_lock(&tu->ioctl_lock);
2044         ret = __snd_timer_user_ioctl(file, cmd, arg);
2045         mutex_unlock(&tu->ioctl_lock);
2046         return ret;
2047 }
2048
2049 static int snd_timer_user_fasync(int fd, struct file * file, int on)
2050 {
2051         struct snd_timer_user *tu;
2052
2053         tu = file->private_data;
2054         return snd_fasync_helper(fd, file, on, &tu->fasync);
2055 }
2056
2057 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2058                                    size_t count, loff_t *offset)
2059 {
2060         struct snd_timer_user *tu;
2061         long result = 0, unit;
2062         int qhead;
2063         int err = 0;
2064
2065         tu = file->private_data;
2066         unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
2067         mutex_lock(&tu->ioctl_lock);
2068         spin_lock_irq(&tu->qlock);
2069         while ((long)count - result >= unit) {
2070                 while (!tu->qused) {
2071                         wait_queue_entry_t wait;
2072
2073                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2074                                 err = -EAGAIN;
2075                                 goto _error;
2076                         }
2077
2078                         set_current_state(TASK_INTERRUPTIBLE);
2079                         init_waitqueue_entry(&wait, current);
2080                         add_wait_queue(&tu->qchange_sleep, &wait);
2081
2082                         spin_unlock_irq(&tu->qlock);
2083                         mutex_unlock(&tu->ioctl_lock);
2084                         schedule();
2085                         mutex_lock(&tu->ioctl_lock);
2086                         spin_lock_irq(&tu->qlock);
2087
2088                         remove_wait_queue(&tu->qchange_sleep, &wait);
2089
2090                         if (tu->disconnected) {
2091                                 err = -ENODEV;
2092                                 goto _error;
2093                         }
2094                         if (signal_pending(current)) {
2095                                 err = -ERESTARTSYS;
2096                                 goto _error;
2097                         }
2098                 }
2099
2100                 qhead = tu->qhead++;
2101                 tu->qhead %= tu->queue_size;
2102                 tu->qused--;
2103                 spin_unlock_irq(&tu->qlock);
2104
2105                 if (tu->tread) {
2106                         if (copy_to_user(buffer, &tu->tqueue[qhead],
2107                                          sizeof(struct snd_timer_tread)))
2108                                 err = -EFAULT;
2109                 } else {
2110                         if (copy_to_user(buffer, &tu->queue[qhead],
2111                                          sizeof(struct snd_timer_read)))
2112                                 err = -EFAULT;
2113                 }
2114
2115                 spin_lock_irq(&tu->qlock);
2116                 if (err < 0)
2117                         goto _error;
2118                 result += unit;
2119                 buffer += unit;
2120         }
2121  _error:
2122         spin_unlock_irq(&tu->qlock);
2123         mutex_unlock(&tu->ioctl_lock);
2124         return result > 0 ? result : err;
2125 }
2126
2127 static __poll_t snd_timer_user_poll(struct file *file, poll_table * wait)
2128 {
2129         __poll_t mask;
2130         struct snd_timer_user *tu;
2131
2132         tu = file->private_data;
2133
2134         poll_wait(file, &tu->qchange_sleep, wait);
2135
2136         mask = 0;
2137         spin_lock_irq(&tu->qlock);
2138         if (tu->qused)
2139                 mask |= EPOLLIN | EPOLLRDNORM;
2140         if (tu->disconnected)
2141                 mask |= EPOLLERR;
2142         spin_unlock_irq(&tu->qlock);
2143
2144         return mask;
2145 }
2146
2147 #ifdef CONFIG_COMPAT
2148 #include "timer_compat.c"
2149 #else
2150 #define snd_timer_user_ioctl_compat     NULL
2151 #endif
2152
2153 static const struct file_operations snd_timer_f_ops =
2154 {
2155         .owner =        THIS_MODULE,
2156         .read =         snd_timer_user_read,
2157         .open =         snd_timer_user_open,
2158         .release =      snd_timer_user_release,
2159         .llseek =       no_llseek,
2160         .poll =         snd_timer_user_poll,
2161         .unlocked_ioctl =       snd_timer_user_ioctl,
2162         .compat_ioctl = snd_timer_user_ioctl_compat,
2163         .fasync =       snd_timer_user_fasync,
2164 };
2165
2166 /* unregister the system timer */
2167 static void snd_timer_free_all(void)
2168 {
2169         struct snd_timer *timer, *n;
2170
2171         list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2172                 snd_timer_free(timer);
2173 }
2174
2175 static struct device timer_dev;
2176
2177 /*
2178  *  ENTRY functions
2179  */
2180
2181 static int __init alsa_timer_init(void)
2182 {
2183         int err;
2184
2185         snd_device_initialize(&timer_dev, NULL);
2186         dev_set_name(&timer_dev, "timer");
2187
2188 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2189         snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2190                               "system timer");
2191 #endif
2192
2193         err = snd_timer_register_system();
2194         if (err < 0) {
2195                 pr_err("ALSA: unable to register system timer (%i)\n", err);
2196                 goto put_timer;
2197         }
2198
2199         err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2200                                   &snd_timer_f_ops, NULL, &timer_dev);
2201         if (err < 0) {
2202                 pr_err("ALSA: unable to register timer device (%i)\n", err);
2203                 snd_timer_free_all();
2204                 goto put_timer;
2205         }
2206
2207         snd_timer_proc_init();
2208         return 0;
2209
2210 put_timer:
2211         put_device(&timer_dev);
2212         return err;
2213 }
2214
2215 static void __exit alsa_timer_exit(void)
2216 {
2217         snd_unregister_device(&timer_dev);
2218         snd_timer_free_all();
2219         put_device(&timer_dev);
2220         snd_timer_proc_done();
2221 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2222         snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2223 #endif
2224 }
2225
2226 module_init(alsa_timer_init)
2227 module_exit(alsa_timer_exit)