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