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 fasync_struct *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         list_for_each_entry(ts, &ti->slave_active_head, active_list)
 495                 if (ts->ccallback)
 496                         ts->ccallback(ts, event + 100, &tstamp, resolution);
 497 }
 498
 499 /* start/continue a master timer */
 500 static int snd_timer_start1(struct snd_timer_instance *timeri,
 501                             bool start, unsigned long ticks)
 502 {
 503         struct snd_timer *timer;
 504         int result;
 505         unsigned long flags;
 506
 507         timer = timeri->timer;
 508         if (!timer)
 509                 return -EINVAL;
 510
 511         spin_lock_irqsave(&timer->lock, flags);
 512         if (timeri->flags & SNDRV_TIMER_IFLG_DEAD) {
 513                 result = -EINVAL;
 514                 goto unlock;
 515         }
 516         if (timer->card && timer->card->shutdown) {
 517                 result = -ENODEV;
 518                 goto unlock;
 519         }
 520         if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 521                              SNDRV_TIMER_IFLG_START)) {
 522                 result = -EBUSY;
 523                 goto unlock;
 524         }
 525
 526         if (start)
 527                 timeri->ticks = timeri->cticks = ticks;
 528         else if (!timeri->cticks)
 529                 timeri->cticks = 1;
 530         timeri->pticks = 0;
 531
 532         list_move_tail(&timeri->active_list, &timer->active_list_head);
 533         if (timer->running) {
 534                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 535                         goto __start_now;
 536                 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
 537                 timeri->flags |= SNDRV_TIMER_IFLG_START;
 538                 result = 1; /* delayed start */
 539         } else {
 540                 if (start)
 541                         timer->sticks = ticks;
 542                 timer->hw.start(timer);
 543               __start_now:
 544                 timer->running++;
 545                 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 546                 result = 0;
 547         }
 548         snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 549                           SNDRV_TIMER_EVENT_CONTINUE);
 550  unlock:
 551         spin_unlock_irqrestore(&timer->lock, flags);
 552         return result;
 553 }
 554
 555 /* start/continue a slave timer */
 556 static int snd_timer_start_slave(struct snd_timer_instance *timeri,
 557                                  bool start)
 558 {
 559         unsigned long flags;
 560         int err;
 561
 562         spin_lock_irqsave(&slave_active_lock, flags);
 563         if (timeri->flags & SNDRV_TIMER_IFLG_DEAD) {
 564                 err = -EINVAL;
 565                 goto unlock;
 566         }
 567         if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) {
 568                 err = -EBUSY;
 569                 goto unlock;
 570         }
 571         timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 572         if (timeri->master && timeri->timer) {
 573                 spin_lock(&timeri->timer->lock);
 574                 list_add_tail(&timeri->active_list,
 575                               &timeri->master->slave_active_head);
 576                 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 577                                   SNDRV_TIMER_EVENT_CONTINUE);
 578                 spin_unlock(&timeri->timer->lock);
 579         }
 580         err = 1; /* delayed start */
 581  unlock:
 582         spin_unlock_irqrestore(&slave_active_lock, flags);
 583         return err;
 584 }
 585
 586 /* stop/pause a master timer */
 587 static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
 588 {
 589         struct snd_timer *timer;
 590         int result = 0;
 591         unsigned long flags;
 592
 593         timer = timeri->timer;
 594         if (!timer)
 595                 return -EINVAL;
 596         spin_lock_irqsave(&timer->lock, flags);
 597         if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 598                                SNDRV_TIMER_IFLG_START))) {
 599                 result = -EBUSY;
 600                 goto unlock;
 601         }
 602         list_del_init(&timeri->ack_list);
 603         list_del_init(&timeri->active_list);
 604         if (timer->card && timer->card->shutdown)
 605                 goto unlock;
 606         if (stop) {
 607                 timeri->cticks = timeri->ticks;
 608                 timeri->pticks = 0;
 609         }
 610         if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
 611             !(--timer->running)) {
 612                 timer->hw.stop(timer);
 613                 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
 614                         timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 615                         snd_timer_reschedule(timer, 0);
 616                         if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
 617                                 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 618                                 timer->hw.start(timer);
 619                         }
 620                 }
 621         }
 622         timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
 623         if (stop)
 624                 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
 625         else
 626                 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
 627         snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 628                           SNDRV_TIMER_EVENT_PAUSE);
 629  unlock:
 630         spin_unlock_irqrestore(&timer->lock, flags);
 631         return result;
 632 }
 633
 634 /* stop/pause a slave timer */
 635 static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
 636 {
 637         unsigned long flags;
 638
 639         spin_lock_irqsave(&slave_active_lock, flags);
 640         if (!(timeri->flags & SNDRV_TIMER_IFLG_RUNNING)) {
 641                 spin_unlock_irqrestore(&slave_active_lock, flags);
 642                 return -EBUSY;
 643         }
 644         timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 645         if (timeri->timer) {
 646                 spin_lock(&timeri->timer->lock);
 647                 list_del_init(&timeri->ack_list);
 648                 list_del_init(&timeri->active_list);
 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 0;
 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         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         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         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                 kfree(tu->queue);
1491                 kfree(tu->tqueue);
1492                 kfree(tu);
1493         }
1494         return 0;
1495 }
1496
1497 static void snd_timer_user_zero_id(struct snd_timer_id *id)
1498 {
1499         id->dev_class = SNDRV_TIMER_CLASS_NONE;
1500         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1501         id->card = -1;
1502         id->device = -1;
1503         id->subdevice = -1;
1504 }
1505
1506 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1507 {
1508         id->dev_class = timer->tmr_class;
1509         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1510         id->card = timer->card ? timer->card->number : -1;
1511         id->device = timer->tmr_device;
1512         id->subdevice = timer->tmr_subdevice;
1513 }
1514
1515 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1516 {
1517         struct snd_timer_id id;
1518         struct snd_timer *timer;
1519         struct list_head *p;
1520
1521         if (copy_from_user(&id, _tid, sizeof(id)))
1522                 return -EFAULT;
1523         mutex_lock(&register_mutex);
1524         if (id.dev_class < 0) {         /* first item */
1525                 if (list_empty(&snd_timer_list))
1526                         snd_timer_user_zero_id(&id);
1527                 else {
1528                         timer = list_entry(snd_timer_list.next,
1529                                            struct snd_timer, device_list);
1530                         snd_timer_user_copy_id(&id, timer);
1531                 }
1532         } else {
1533                 switch (id.dev_class) {
1534                 case SNDRV_TIMER_CLASS_GLOBAL:
1535                         id.device = id.device < 0 ? 0 : id.device + 1;
1536                         list_for_each(p, &snd_timer_list) {
1537                                 timer = list_entry(p, struct snd_timer, device_list);
1538                                 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1539                                         snd_timer_user_copy_id(&id, timer);
1540                                         break;
1541                                 }
1542                                 if (timer->tmr_device >= id.device) {
1543                                         snd_timer_user_copy_id(&id, timer);
1544                                         break;
1545                                 }
1546                         }
1547                         if (p == &snd_timer_list)
1548                                 snd_timer_user_zero_id(&id);
1549                         break;
1550                 case SNDRV_TIMER_CLASS_CARD:
1551                 case SNDRV_TIMER_CLASS_PCM:
1552                         if (id.card < 0) {
1553                                 id.card = 0;
1554                         } else {
1555                                 if (id.device < 0) {
1556                                         id.device = 0;
1557                                 } else {
1558                                         if (id.subdevice < 0)
1559                                                 id.subdevice = 0;
1560                                         else if (id.subdevice < INT_MAX)
1561                                                 id.subdevice++;
1562                                 }
1563                         }
1564                         list_for_each(p, &snd_timer_list) {
1565                                 timer = list_entry(p, struct snd_timer, device_list);
1566                                 if (timer->tmr_class > id.dev_class) {
1567                                         snd_timer_user_copy_id(&id, timer);
1568                                         break;
1569                                 }
1570                                 if (timer->tmr_class < id.dev_class)
1571                                         continue;
1572                                 if (timer->card->number > id.card) {
1573                                         snd_timer_user_copy_id(&id, timer);
1574                                         break;
1575                                 }
1576                                 if (timer->card->number < id.card)
1577                                         continue;
1578                                 if (timer->tmr_device > id.device) {
1579                                         snd_timer_user_copy_id(&id, timer);
1580                                         break;
1581                                 }
1582                                 if (timer->tmr_device < id.device)
1583                                         continue;
1584                                 if (timer->tmr_subdevice > id.subdevice) {
1585                                         snd_timer_user_copy_id(&id, timer);
1586                                         break;
1587                                 }
1588                                 if (timer->tmr_subdevice < id.subdevice)
1589                                         continue;
1590                                 snd_timer_user_copy_id(&id, timer);
1591                                 break;
1592                         }
1593                         if (p == &snd_timer_list)
1594                                 snd_timer_user_zero_id(&id);
1595                         break;
1596                 default:
1597                         snd_timer_user_zero_id(&id);
1598                 }
1599         }
1600         mutex_unlock(&register_mutex);
1601         if (copy_to_user(_tid, &id, sizeof(*_tid)))
1602                 return -EFAULT;
1603         return 0;
1604 }
1605
1606 static int snd_timer_user_ginfo(struct file *file,
1607                                 struct snd_timer_ginfo __user *_ginfo)
1608 {
1609         struct snd_timer_ginfo *ginfo;
1610         struct snd_timer_id tid;
1611         struct snd_timer *t;
1612         struct list_head *p;
1613         int err = 0;
1614
1615         ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1616         if (IS_ERR(ginfo))
1617                 return PTR_ERR(ginfo);
1618
1619         tid = ginfo->tid;
1620         memset(ginfo, 0, sizeof(*ginfo));
1621         ginfo->tid = tid;
1622         mutex_lock(&register_mutex);
1623         t = snd_timer_find(&tid);
1624         if (t != NULL) {
1625                 ginfo->card = t->card ? t->card->number : -1;
1626                 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1627                         ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1628                 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1629                 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1630                 ginfo->resolution = t->hw.resolution;
1631                 if (t->hw.resolution_min > 0) {
1632                         ginfo->resolution_min = t->hw.resolution_min;
1633                         ginfo->resolution_max = t->hw.resolution_max;
1634                 }
1635                 list_for_each(p, &t->open_list_head) {
1636                         ginfo->clients++;
1637                 }
1638         } else {
1639                 err = -ENODEV;
1640         }
1641         mutex_unlock(&register_mutex);
1642         if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1643                 err = -EFAULT;
1644         kfree(ginfo);
1645         return err;
1646 }
1647
1648 static int timer_set_gparams(struct snd_timer_gparams *gparams)
1649 {
1650         struct snd_timer *t;
1651         int err;
1652
1653         mutex_lock(&register_mutex);
1654         t = snd_timer_find(&gparams->tid);
1655         if (!t) {
1656                 err = -ENODEV;
1657                 goto _error;
1658         }
1659         if (!list_empty(&t->open_list_head)) {
1660                 err = -EBUSY;
1661                 goto _error;
1662         }
1663         if (!t->hw.set_period) {
1664                 err = -ENOSYS;
1665                 goto _error;
1666         }
1667         err = t->hw.set_period(t, gparams->period_num, gparams->period_den);
1668 _error:
1669         mutex_unlock(&register_mutex);
1670         return err;
1671 }
1672
1673 static int snd_timer_user_gparams(struct file *file,
1674                                   struct snd_timer_gparams __user *_gparams)
1675 {
1676         struct snd_timer_gparams gparams;
1677
1678         if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1679                 return -EFAULT;
1680         return timer_set_gparams(&gparams);
1681 }
1682
1683 static int snd_timer_user_gstatus(struct file *file,
1684                                   struct snd_timer_gstatus __user *_gstatus)
1685 {
1686         struct snd_timer_gstatus gstatus;
1687         struct snd_timer_id tid;
1688         struct snd_timer *t;
1689         int err = 0;
1690
1691         if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1692                 return -EFAULT;
1693         tid = gstatus.tid;
1694         memset(&gstatus, 0, sizeof(gstatus));
1695         gstatus.tid = tid;
1696         mutex_lock(&register_mutex);
1697         t = snd_timer_find(&tid);
1698         if (t != NULL) {
1699                 spin_lock_irq(&t->lock);
1700                 gstatus.resolution = snd_timer_hw_resolution(t);
1701                 if (t->hw.precise_resolution) {
1702                         t->hw.precise_resolution(t, &gstatus.resolution_num,
1703                                                  &gstatus.resolution_den);
1704                 } else {
1705                         gstatus.resolution_num = gstatus.resolution;
1706                         gstatus.resolution_den = 1000000000uL;
1707                 }
1708                 spin_unlock_irq(&t->lock);
1709         } else {
1710                 err = -ENODEV;
1711         }
1712         mutex_unlock(&register_mutex);
1713         if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1714                 err = -EFAULT;
1715         return err;
1716 }
1717
1718 static int snd_timer_user_tselect(struct file *file,
1719                                   struct snd_timer_select __user *_tselect)
1720 {
1721         struct snd_timer_user *tu;
1722         struct snd_timer_select tselect;
1723         char str[32];
1724         int err = 0;
1725
1726         tu = file->private_data;
1727         if (tu->timeri) {
1728                 snd_timer_close(tu->timeri);
1729                 tu->timeri = NULL;
1730         }
1731         if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1732                 err = -EFAULT;
1733                 goto __err;
1734         }
1735         sprintf(str, "application %i", current->pid);
1736         if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1737                 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1738         err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1739         if (err < 0)
1740                 goto __err;
1741
1742         tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1743         tu->timeri->callback = tu->tread
1744                         ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1745         tu->timeri->ccallback = snd_timer_user_ccallback;
1746         tu->timeri->callback_data = (void *)tu;
1747         tu->timeri->disconnect = snd_timer_user_disconnect;
1748
1749       __err:
1750         return err;
1751 }
1752
1753 static int snd_timer_user_info(struct file *file,
1754                                struct snd_timer_info __user *_info)
1755 {
1756         struct snd_timer_user *tu;
1757         struct snd_timer_info *info;
1758         struct snd_timer *t;
1759         int err = 0;
1760
1761         tu = file->private_data;
1762         if (!tu->timeri)
1763                 return -EBADFD;
1764         t = tu->timeri->timer;
1765         if (!t)
1766                 return -EBADFD;
1767
1768         info = kzalloc(sizeof(*info), GFP_KERNEL);
1769         if (! info)
1770                 return -ENOMEM;
1771         info->card = t->card ? t->card->number : -1;
1772         if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1773                 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1774         strlcpy(info->id, t->id, sizeof(info->id));
1775         strlcpy(info->name, t->name, sizeof(info->name));
1776         info->resolution = t->hw.resolution;
1777         if (copy_to_user(_info, info, sizeof(*_info)))
1778                 err = -EFAULT;
1779         kfree(info);
1780         return err;
1781 }
1782
1783 static int snd_timer_user_params(struct file *file,
1784                                  struct snd_timer_params __user *_params)
1785 {
1786         struct snd_timer_user *tu;
1787         struct snd_timer_params params;
1788         struct snd_timer *t;
1789         int err;
1790
1791         tu = file->private_data;
1792         if (!tu->timeri)
1793                 return -EBADFD;
1794         t = tu->timeri->timer;
1795         if (!t)
1796                 return -EBADFD;
1797         if (copy_from_user(&params, _params, sizeof(params)))
1798                 return -EFAULT;
1799         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1800                 u64 resolution;
1801
1802                 if (params.ticks < 1) {
1803                         err = -EINVAL;
1804                         goto _end;
1805                 }
1806
1807                 /* Don't allow resolution less than 1ms */
1808                 resolution = snd_timer_resolution(tu->timeri);
1809                 resolution *= params.ticks;
1810                 if (resolution < 1000000) {
1811                         err = -EINVAL;
1812                         goto _end;
1813                 }
1814         }
1815         if (params.queue_size > 0 &&
1816             (params.queue_size < 32 || params.queue_size > 1024)) {
1817                 err = -EINVAL;
1818                 goto _end;
1819         }
1820         if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1821                               (1<<SNDRV_TIMER_EVENT_TICK)|
1822                               (1<<SNDRV_TIMER_EVENT_START)|
1823                               (1<<SNDRV_TIMER_EVENT_STOP)|
1824                               (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1825                               (1<<SNDRV_TIMER_EVENT_PAUSE)|
1826                               (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1827                               (1<<SNDRV_TIMER_EVENT_RESUME)|
1828                               (1<<SNDRV_TIMER_EVENT_MSTART)|
1829                               (1<<SNDRV_TIMER_EVENT_MSTOP)|
1830                               (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1831                               (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1832                               (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1833                               (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1834                 err = -EINVAL;
1835                 goto _end;
1836         }
1837         snd_timer_stop(tu->timeri);
1838         spin_lock_irq(&t->lock);
1839         tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1840                                SNDRV_TIMER_IFLG_EXCLUSIVE|
1841                                SNDRV_TIMER_IFLG_EARLY_EVENT);
1842         if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1843                 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1844         if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1845                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1846         if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1847                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1848         spin_unlock_irq(&t->lock);
1849         if (params.queue_size > 0 &&
1850             (unsigned int)tu->queue_size != params.queue_size) {
1851                 err = realloc_user_queue(tu, params.queue_size);
1852                 if (err < 0)
1853                         goto _end;
1854         }
1855         spin_lock_irq(&tu->qlock);
1856         tu->qhead = tu->qtail = tu->qused = 0;
1857         if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1858                 if (tu->tread) {
1859                         struct snd_timer_tread tread;
1860                         memset(&tread, 0, sizeof(tread));
1861                         tread.event = SNDRV_TIMER_EVENT_EARLY;
1862                         tread.tstamp.tv_sec = 0;
1863                         tread.tstamp.tv_nsec = 0;
1864                         tread.val = 0;
1865                         snd_timer_user_append_to_tqueue(tu, &tread);
1866                 } else {
1867                         struct snd_timer_read *r = &tu->queue[0];
1868                         r->resolution = 0;
1869                         r->ticks = 0;
1870                         tu->qused++;
1871                         tu->qtail++;
1872                 }
1873         }
1874         tu->filter = params.filter;
1875         tu->ticks = params.ticks;
1876         spin_unlock_irq(&tu->qlock);
1877         err = 0;
1878  _end:
1879         if (copy_to_user(_params, &params, sizeof(params)))
1880                 return -EFAULT;
1881         return err;
1882 }
1883
1884 static int snd_timer_user_status(struct file *file,
1885                                  struct snd_timer_status __user *_status)
1886 {
1887         struct snd_timer_user *tu;
1888         struct snd_timer_status status;
1889
1890         tu = file->private_data;
1891         if (!tu->timeri)
1892                 return -EBADFD;
1893         memset(&status, 0, sizeof(status));
1894         status.tstamp = tu->tstamp;
1895         status.resolution = snd_timer_resolution(tu->timeri);
1896         status.lost = tu->timeri->lost;
1897         status.overrun = tu->overrun;
1898         spin_lock_irq(&tu->qlock);
1899         status.queue = tu->qused;
1900         spin_unlock_irq(&tu->qlock);
1901         if (copy_to_user(_status, &status, sizeof(status)))
1902                 return -EFAULT;
1903         return 0;
1904 }
1905
1906 static int snd_timer_user_start(struct file *file)
1907 {
1908         int err;
1909         struct snd_timer_user *tu;
1910
1911         tu = file->private_data;
1912         if (!tu->timeri)
1913                 return -EBADFD;
1914         snd_timer_stop(tu->timeri);
1915         tu->timeri->lost = 0;
1916         tu->last_resolution = 0;
1917         err = snd_timer_start(tu->timeri, tu->ticks);
1918         if (err < 0)
1919                 return err;
1920         return 0;
1921 }
1922
1923 static int snd_timer_user_stop(struct file *file)
1924 {
1925         int err;
1926         struct snd_timer_user *tu;
1927
1928         tu = file->private_data;
1929         if (!tu->timeri)
1930                 return -EBADFD;
1931         err = snd_timer_stop(tu->timeri);
1932         if (err < 0)
1933                 return err;
1934         return 0;
1935 }
1936
1937 static int snd_timer_user_continue(struct file *file)
1938 {
1939         int err;
1940         struct snd_timer_user *tu;
1941
1942         tu = file->private_data;
1943         if (!tu->timeri)
1944                 return -EBADFD;
1945         /* start timer instead of continue if it's not used before */
1946         if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
1947                 return snd_timer_user_start(file);
1948         tu->timeri->lost = 0;
1949         err = snd_timer_continue(tu->timeri);
1950         if (err < 0)
1951                 return err;
1952         return 0;
1953 }
1954
1955 static int snd_timer_user_pause(struct file *file)
1956 {
1957         int err;
1958         struct snd_timer_user *tu;
1959
1960         tu = file->private_data;
1961         if (!tu->timeri)
1962                 return -EBADFD;
1963         err = snd_timer_pause(tu->timeri);
1964         if (err < 0)
1965                 return err;
1966         return 0;
1967 }
1968
1969 enum {
1970         SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1971         SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1972         SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1973         SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1974 };
1975
1976 static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1977                                  unsigned long arg)
1978 {
1979         struct snd_timer_user *tu;
1980         void __user *argp = (void __user *)arg;
1981         int __user *p = argp;
1982
1983         tu = file->private_data;
1984         switch (cmd) {
1985         case SNDRV_TIMER_IOCTL_PVERSION:
1986                 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1987         case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1988                 return snd_timer_user_next_device(argp);
1989         case SNDRV_TIMER_IOCTL_TREAD:
1990         {
1991                 int xarg, old_tread;
1992
1993                 if (tu->timeri) /* too late */
1994                         return -EBUSY;
1995                 if (get_user(xarg, p))
1996                         return -EFAULT;
1997                 old_tread = tu->tread;
1998                 tu->tread = xarg ? 1 : 0;
1999                 if (tu->tread != old_tread &&
2000                     realloc_user_queue(tu, tu->queue_size) < 0) {
2001                         tu->tread = old_tread;
2002                         return -ENOMEM;
2003                 }
2004                 return 0;
2005         }
2006         case SNDRV_TIMER_IOCTL_GINFO:
2007                 return snd_timer_user_ginfo(file, argp);
2008         case SNDRV_TIMER_IOCTL_GPARAMS:
2009                 return snd_timer_user_gparams(file, argp);
2010         case SNDRV_TIMER_IOCTL_GSTATUS:
2011                 return snd_timer_user_gstatus(file, argp);
2012         case SNDRV_TIMER_IOCTL_SELECT:
2013                 return snd_timer_user_tselect(file, argp);
2014         case SNDRV_TIMER_IOCTL_INFO:
2015                 return snd_timer_user_info(file, argp);
2016         case SNDRV_TIMER_IOCTL_PARAMS:
2017                 return snd_timer_user_params(file, argp);
2018         case SNDRV_TIMER_IOCTL_STATUS:
2019                 return snd_timer_user_status(file, argp);
2020         case SNDRV_TIMER_IOCTL_START:
2021         case SNDRV_TIMER_IOCTL_START_OLD:
2022                 return snd_timer_user_start(file);
2023         case SNDRV_TIMER_IOCTL_STOP:
2024         case SNDRV_TIMER_IOCTL_STOP_OLD:
2025                 return snd_timer_user_stop(file);
2026         case SNDRV_TIMER_IOCTL_CONTINUE:
2027         case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
2028                 return snd_timer_user_continue(file);
2029         case SNDRV_TIMER_IOCTL_PAUSE:
2030         case SNDRV_TIMER_IOCTL_PAUSE_OLD:
2031                 return snd_timer_user_pause(file);
2032         }
2033         return -ENOTTY;
2034 }
2035
2036 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2037                                  unsigned long arg)
2038 {
2039         struct snd_timer_user *tu = file->private_data;
2040         long ret;
2041
2042         mutex_lock(&tu->ioctl_lock);
2043         ret = __snd_timer_user_ioctl(file, cmd, arg);
2044         mutex_unlock(&tu->ioctl_lock);
2045         return ret;
2046 }
2047
2048 static int snd_timer_user_fasync(int fd, struct file * file, int on)
2049 {
2050         struct snd_timer_user *tu;
2051
2052         tu = file->private_data;
2053         return fasync_helper(fd, file, on, &tu->fasync);
2054 }
2055
2056 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2057                                    size_t count, loff_t *offset)
2058 {
2059         struct snd_timer_user *tu;
2060         long result = 0, unit;
2061         int qhead;
2062         int err = 0;
2063
2064         tu = file->private_data;
2065         unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
2066         mutex_lock(&tu->ioctl_lock);
2067         spin_lock_irq(&tu->qlock);
2068         while ((long)count - result >= unit) {
2069                 while (!tu->qused) {
2070                         wait_queue_entry_t wait;
2071
2072                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2073                                 err = -EAGAIN;
2074                                 goto _error;
2075                         }
2076
2077                         set_current_state(TASK_INTERRUPTIBLE);
2078                         init_waitqueue_entry(&wait, current);
2079                         add_wait_queue(&tu->qchange_sleep, &wait);
2080
2081                         spin_unlock_irq(&tu->qlock);
2082                         mutex_unlock(&tu->ioctl_lock);
2083                         schedule();
2084                         mutex_lock(&tu->ioctl_lock);
2085                         spin_lock_irq(&tu->qlock);
2086
2087                         remove_wait_queue(&tu->qchange_sleep, &wait);
2088
2089                         if (tu->disconnected) {
2090                                 err = -ENODEV;
2091                                 goto _error;
2092                         }
2093                         if (signal_pending(current)) {
2094                                 err = -ERESTARTSYS;
2095                                 goto _error;
2096                         }
2097                 }
2098
2099                 qhead = tu->qhead++;
2100                 tu->qhead %= tu->queue_size;
2101                 tu->qused--;
2102                 spin_unlock_irq(&tu->qlock);
2103
2104                 if (tu->tread) {
2105                         if (copy_to_user(buffer, &tu->tqueue[qhead],
2106                                          sizeof(struct snd_timer_tread)))
2107                                 err = -EFAULT;
2108                 } else {
2109                         if (copy_to_user(buffer, &tu->queue[qhead],
2110                                          sizeof(struct snd_timer_read)))
2111                                 err = -EFAULT;
2112                 }
2113
2114                 spin_lock_irq(&tu->qlock);
2115                 if (err < 0)
2116                         goto _error;
2117                 result += unit;
2118                 buffer += unit;
2119         }
2120  _error:
2121         spin_unlock_irq(&tu->qlock);
2122         mutex_unlock(&tu->ioctl_lock);
2123         return result > 0 ? result : err;
2124 }
2125
2126 static __poll_t snd_timer_user_poll(struct file *file, poll_table * wait)
2127 {
2128         __poll_t mask;
2129         struct snd_timer_user *tu;
2130
2131         tu = file->private_data;
2132
2133         poll_wait(file, &tu->qchange_sleep, wait);
2134
2135         mask = 0;
2136         spin_lock_irq(&tu->qlock);
2137         if (tu->qused)
2138                 mask |= EPOLLIN | EPOLLRDNORM;
2139         if (tu->disconnected)
2140                 mask |= EPOLLERR;
2141         spin_unlock_irq(&tu->qlock);
2142
2143         return mask;
2144 }
2145
2146 #ifdef CONFIG_COMPAT
2147 #include "timer_compat.c"
2148 #else
2149 #define snd_timer_user_ioctl_compat     NULL
2150 #endif
2151
2152 static const struct file_operations snd_timer_f_ops =
2153 {
2154         .owner =        THIS_MODULE,
2155         .read =         snd_timer_user_read,
2156         .open =         snd_timer_user_open,
2157         .release =      snd_timer_user_release,
2158         .llseek =       no_llseek,
2159         .poll =         snd_timer_user_poll,
2160         .unlocked_ioctl =       snd_timer_user_ioctl,
2161         .compat_ioctl = snd_timer_user_ioctl_compat,
2162         .fasync =       snd_timer_user_fasync,
2163 };
2164
2165 /* unregister the system timer */
2166 static void snd_timer_free_all(void)
2167 {
2168         struct snd_timer *timer, *n;
2169
2170         list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2171                 snd_timer_free(timer);
2172 }
2173
2174 static struct device timer_dev;
2175
2176 /*
2177  *  ENTRY functions
2178  */
2179
2180 static int __init alsa_timer_init(void)
2181 {
2182         int err;
2183
2184         snd_device_initialize(&timer_dev, NULL);
2185         dev_set_name(&timer_dev, "timer");
2186
2187 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2188         snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2189                               "system timer");
2190 #endif
2191
2192         err = snd_timer_register_system();
2193         if (err < 0) {
2194                 pr_err("ALSA: unable to register system timer (%i)\n", err);
2195                 goto put_timer;
2196         }
2197
2198         err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2199                                   &snd_timer_f_ops, NULL, &timer_dev);
2200         if (err < 0) {
2201                 pr_err("ALSA: unable to register timer device (%i)\n", err);
2202                 snd_timer_free_all();
2203                 goto put_timer;
2204         }
2205
2206         snd_timer_proc_init();
2207         return 0;
2208
2209 put_timer:
2210         put_device(&timer_dev);
2211         return err;
2212 }
2213
2214 static void __exit alsa_timer_exit(void)
2215 {
2216         snd_unregister_device(&timer_dev);
2217         snd_timer_free_all();
2218         put_device(&timer_dev);
2219         snd_timer_proc_done();
2220 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2221         snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2222 #endif
2223 }
2224
2225 module_init(alsa_timer_init)
2226 module_exit(alsa_timer_exit)