sound/core/timer.c

   1 /*
   2  *  Timers abstract layer
   3  *  Copyright (c) by Jaroslav Kysela <[email protected]>
   4  *
   5  *
   6  *   This program is free software; you can redistribute it and/or modify
   7  *   it under the terms of the GNU General Public License as published by
   8  *   the Free Software Foundation; either version 2 of the License, or
   9  *   (at your option) any later version.
  10  *
  11  *   This program is distributed in the hope that it will be useful,
  12  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *   GNU General Public License for more details.
  15  *
  16  *   You should have received a copy of the GNU General Public License
  17  *   along with this program; if not, write to the Free Software
  18  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  *
  20  */
  21
  22 #include <linux/delay.h>
  23 #include <linux/init.h>
  24 #include <linux/slab.h>
  25 #include <linux/time.h>
  26 #include <linux/mutex.h>
  27 #include <linux/device.h>
  28 #include <linux/module.h>
  29 #include <linux/string.h>
  30 #include <linux/sched/signal.h>
  31 #include <sound/core.h>
  32 #include <sound/timer.h>
  33 #include <sound/control.h>
  34 #include <sound/info.h>
  35 #include <sound/minors.h>
  36 #include <sound/initval.h>
  37 #include <linux/kmod.h>
  38
  39 /* internal flags */
  40 #define SNDRV_TIMER_IFLG_PAUSED         0x00010000
  41
  42 #if IS_ENABLED(CONFIG_SND_HRTIMER)
  43 #define DEFAULT_TIMER_LIMIT 4
  44 #else
  45 #define DEFAULT_TIMER_LIMIT 1
  46 #endif
  47
  48 static int timer_limit = DEFAULT_TIMER_LIMIT;
  49 static int timer_tstamp_monotonic = 1;
  50 MODULE_AUTHOR("Jaroslav Kysela <[email protected]>, Takashi Iwai <[email protected]>");
  51 MODULE_DESCRIPTION("ALSA timer interface");
  52 MODULE_LICENSE("GPL");
  53 module_param(timer_limit, int, 0444);
  54 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
  55 module_param(timer_tstamp_monotonic, int, 0444);
  56 MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
  57
  58 MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
  59 MODULE_ALIAS("devname:snd/timer");
  60
  61 struct snd_timer_user {
  62         struct snd_timer_instance *timeri;
  63         int tread;              /* enhanced read with timestamps and events */
  64         unsigned long ticks;
  65         unsigned long overrun;
  66         int qhead;
  67         int qtail;
  68         int qused;
  69         int queue_size;
  70         bool disconnected;
  71         struct snd_timer_read *queue;
  72         struct snd_timer_tread *tqueue;
  73         spinlock_t qlock;
  74         unsigned long last_resolution;
  75         unsigned int filter;
  76         struct timespec tstamp;         /* trigger tstamp */
  77         wait_queue_head_t qchange_sleep;
  78         struct fasync_struct *fasync;
  79         struct mutex ioctl_lock;
  80 };
  81
  82 /* list of timers */
  83 static LIST_HEAD(snd_timer_list);
  84
  85 /* list of slave instances */
  86 static LIST_HEAD(snd_timer_slave_list);
  87
  88 /* lock for slave active lists */
  89 static DEFINE_SPINLOCK(slave_active_lock);
  90
  91 static DEFINE_MUTEX(register_mutex);
  92
  93 static int snd_timer_free(struct snd_timer *timer);
  94 static int snd_timer_dev_free(struct snd_device *device);
  95 static int snd_timer_dev_register(struct snd_device *device);
  96 static int snd_timer_dev_disconnect(struct snd_device *device);
  97
  98 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
  99
 100 /*
 101  * create a timer instance with the given owner string.
 102  * when timer is not NULL, increments the module counter
 103  */
 104 static struct snd_timer_instance *snd_timer_instance_new(char *owner,
 105                                                          struct snd_timer *timer)
 106 {
 107         struct snd_timer_instance *timeri;
 108         timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
 109         if (timeri == NULL)
 110                 return NULL;
 111         timeri->owner = kstrdup(owner, GFP_KERNEL);
 112         if (! timeri->owner) {
 113                 kfree(timeri);
 114                 return NULL;
 115         }
 116         INIT_LIST_HEAD(&timeri->open_list);
 117         INIT_LIST_HEAD(&timeri->active_list);
 118         INIT_LIST_HEAD(&timeri->ack_list);
 119         INIT_LIST_HEAD(&timeri->slave_list_head);
 120         INIT_LIST_HEAD(&timeri->slave_active_head);
 121
 122         timeri->timer = timer;
 123         if (timer && !try_module_get(timer->module)) {
 124                 kfree(timeri->owner);
 125                 kfree(timeri);
 126                 return NULL;
 127         }
 128
 129         return timeri;
 130 }
 131
 132 /*
 133  * find a timer instance from the given timer id
 134  */
 135 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
 136 {
 137         struct snd_timer *timer = NULL;
 138
 139         list_for_each_entry(timer, &snd_timer_list, device_list) {
 140                 if (timer->tmr_class != tid->dev_class)
 141                         continue;
 142                 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
 143                      timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
 144                     (timer->card == NULL ||
 145                      timer->card->number != tid->card))
 146                         continue;
 147                 if (timer->tmr_device != tid->device)
 148                         continue;
 149                 if (timer->tmr_subdevice != tid->subdevice)
 150                         continue;
 151                 return timer;
 152         }
 153         return NULL;
 154 }
 155
 156 #ifdef CONFIG_MODULES
 157
 158 static void snd_timer_request(struct snd_timer_id *tid)
 159 {
 160         switch (tid->dev_class) {
 161         case SNDRV_TIMER_CLASS_GLOBAL:
 162                 if (tid->device < timer_limit)
 163                         request_module("snd-timer-%i", tid->device);
 164                 break;
 165         case SNDRV_TIMER_CLASS_CARD:
 166         case SNDRV_TIMER_CLASS_PCM:
 167                 if (tid->card < snd_ecards_limit)
 168                         request_module("snd-card-%i", tid->card);
 169                 break;
 170         default:
 171                 break;
 172         }
 173 }
 174
 175 #endif
 176
 177 /*
 178  * look for a master instance matching with the slave id of the given slave.
 179  * when found, relink the open_link of the slave.
 180  *
 181  * call this with register_mutex down.
 182  */
 183 static int snd_timer_check_slave(struct snd_timer_instance *slave)
 184 {
 185         struct snd_timer *timer;
 186         struct snd_timer_instance *master;
 187
 188         /* FIXME: it's really dumb to look up all entries.. */
 189         list_for_each_entry(timer, &snd_timer_list, device_list) {
 190                 list_for_each_entry(master, &timer->open_list_head, open_list) {
 191                         if (slave->slave_class == master->slave_class &&
 192                             slave->slave_id == master->slave_id) {
 193                                 if (master->timer->num_instances >=
 194                                     master->timer->max_instances)
 195                                         return -EBUSY;
 196                                 list_move_tail(&slave->open_list,
 197                                                &master->slave_list_head);
 198                                 master->timer->num_instances++;
 199                                 spin_lock_irq(&slave_active_lock);
 200                                 slave->master = master;
 201                                 slave->timer = master->timer;
 202                                 spin_unlock_irq(&slave_active_lock);
 203                                 return 0;
 204                         }
 205                 }
 206         }
 207         return 0;
 208 }
 209
 210 /*
 211  * look for slave instances matching with the slave id of the given master.
 212  * when found, relink the open_link of slaves.
 213  *
 214  * call this with register_mutex down.
 215  */
 216 static int snd_timer_check_master(struct snd_timer_instance *master)
 217 {
 218         struct snd_timer_instance *slave, *tmp;
 219
 220         /* check all pending slaves */
 221         list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
 222                 if (slave->slave_class == master->slave_class &&
 223                     slave->slave_id == master->slave_id) {
 224                         if (master->timer->num_instances >=
 225                             master->timer->max_instances)
 226                                 return -EBUSY;
 227                         list_move_tail(&slave->open_list, &master->slave_list_head);
 228                         master->timer->num_instances++;
 229                         spin_lock_irq(&slave_active_lock);
 230                         spin_lock(&master->timer->lock);
 231                         slave->master = master;
 232                         slave->timer = master->timer;
 233                         if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
 234                                 list_add_tail(&slave->active_list,
 235                                               &master->slave_active_head);
 236                         spin_unlock(&master->timer->lock);
 237                         spin_unlock_irq(&slave_active_lock);
 238                 }
 239         }
 240         return 0;
 241 }
 242
 243 static int snd_timer_close_locked(struct snd_timer_instance *timeri);
 244
 245 /*
 246  * open a timer instance
 247  * when opening a master, the slave id must be here given.
 248  */
 249 int snd_timer_open(struct snd_timer_instance **ti,
 250                    char *owner, struct snd_timer_id *tid,
 251                    unsigned int slave_id)
 252 {
 253         struct snd_timer *timer;
 254         struct snd_timer_instance *timeri = NULL;
 255         int err;
 256
 257         if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
 258                 /* open a slave instance */
 259                 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
 260                     tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
 261                         pr_debug("ALSA: timer: invalid slave class %i\n",
 262                                  tid->dev_sclass);
 263                         return -EINVAL;
 264                 }
 265                 mutex_lock(&register_mutex);
 266                 timeri = snd_timer_instance_new(owner, NULL);
 267                 if (!timeri) {
 268                         mutex_unlock(&register_mutex);
 269                         return -ENOMEM;
 270                 }
 271                 timeri->slave_class = tid->dev_sclass;
 272                 timeri->slave_id = tid->device;
 273                 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
 274                 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
 275                 err = snd_timer_check_slave(timeri);
 276                 if (err < 0) {
 277                         snd_timer_close_locked(timeri);
 278                         timeri = NULL;
 279                 }
 280                 mutex_unlock(&register_mutex);
 281                 *ti = timeri;
 282                 return err;
 283         }
 284
 285         /* open a master instance */
 286         mutex_lock(&register_mutex);
 287         timer = snd_timer_find(tid);
 288 #ifdef CONFIG_MODULES
 289         if (!timer) {
 290                 mutex_unlock(&register_mutex);
 291                 snd_timer_request(tid);
 292                 mutex_lock(&register_mutex);
 293                 timer = snd_timer_find(tid);
 294         }
 295 #endif
 296         if (!timer) {
 297                 mutex_unlock(&register_mutex);
 298                 return -ENODEV;
 299         }
 300         if (!list_empty(&timer->open_list_head)) {
 301                 timeri = list_entry(timer->open_list_head.next,
 302                                     struct snd_timer_instance, open_list);
 303                 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
 304                         mutex_unlock(&register_mutex);
 305                         return -EBUSY;
 306                 }
 307         }
 308         if (timer->num_instances >= timer->max_instances) {
 309                 mutex_unlock(&register_mutex);
 310                 return -EBUSY;
 311         }
 312         timeri = snd_timer_instance_new(owner, timer);
 313         if (!timeri) {
 314                 mutex_unlock(&register_mutex);
 315                 return -ENOMEM;
 316         }
 317         /* take a card refcount for safe disconnection */
 318         if (timer->card)
 319                 get_device(&timer->card->card_dev);
 320         timeri->slave_class = tid->dev_sclass;
 321         timeri->slave_id = slave_id;
 322
 323         if (list_empty(&timer->open_list_head) && timer->hw.open) {
 324                 int err = timer->hw.open(timer);
 325                 if (err) {
 326                         kfree(timeri->owner);
 327                         kfree(timeri);
 328
 329                         if (timer->card)
 330                                 put_device(&timer->card->card_dev);
 331                         module_put(timer->module);
 332                         mutex_unlock(&register_mutex);
 333                         return err;
 334                 }
 335         }
 336
 337         list_add_tail(&timeri->open_list, &timer->open_list_head);
 338         timer->num_instances++;
 339         err = snd_timer_check_master(timeri);
 340         if (err < 0) {
 341                 snd_timer_close_locked(timeri);
 342                 timeri = NULL;
 343         }
 344         mutex_unlock(&register_mutex);
 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 {
 356         struct snd_timer *timer = NULL;
 357         struct snd_timer_instance *slave, *tmp;
 358
 359         list_del(&timeri->open_list);
 360
 361         /* force to stop the timer */
 362         snd_timer_stop(timeri);
 363
 364         timer = timeri->timer;
 365         if (timer) {
 366                 timer->num_instances--;
 367                 /* wait, until the active callback is finished */
 368                 spin_lock_irq(&timer->lock);
 369                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 370                         spin_unlock_irq(&timer->lock);
 371                         udelay(10);
 372                         spin_lock_irq(&timer->lock);
 373                 }
 374                 spin_unlock_irq(&timer->lock);
 375
 376                 /* remove slave links */
 377                 spin_lock_irq(&slave_active_lock);
 378                 spin_lock(&timer->lock);
 379                 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
 380                                          open_list) {
 381                         list_move_tail(&slave->open_list, &snd_timer_slave_list);
 382                         timer->num_instances--;
 383                         slave->master = NULL;
 384                         slave->timer = NULL;
 385                         list_del_init(&slave->ack_list);
 386                         list_del_init(&slave->active_list);
 387                 }
 388                 spin_unlock(&timer->lock);
 389                 spin_unlock_irq(&slave_active_lock);
 390
 391                 /* slave doesn't need to release timer resources below */
 392                 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 393                         timer = NULL;
 394         }
 395
 396         if (timeri->private_free)
 397                 timeri->private_free(timeri);
 398         kfree(timeri->owner);
 399         kfree(timeri);
 400
 401         if (timer) {
 402                 if (list_empty(&timer->open_list_head) && timer->hw.close)
 403                         timer->hw.close(timer);
 404                 /* release a card refcount for safe disconnection */
 405                 if (timer->card)
 406                         put_device(&timer->card->card_dev);
 407                 module_put(timer->module);
 408         }
 409
 410         return 0;
 411 }
 412
 413 /*
 414  * close a timer instance
 415  */
 416 int snd_timer_close(struct snd_timer_instance *timeri)
 417 {
 418         int err;
 419
 420         if (snd_BUG_ON(!timeri))
 421                 return -ENXIO;
 422
 423         mutex_lock(&register_mutex);
 424         err = snd_timer_close_locked(timeri);
 425         mutex_unlock(&register_mutex);
 426         return err;
 427 }
 428 EXPORT_SYMBOL(snd_timer_close);
 429
 430 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
 431 {
 432         struct snd_timer * timer;
 433
 434         if (timeri == NULL)
 435                 return 0;
 436         timer = timeri->timer;
 437         if (timer) {
 438                 if (timer->hw.c_resolution)
 439                         return timer->hw.c_resolution(timer);
 440                 return timer->hw.resolution;
 441         }
 442         return 0;
 443 }
 444 EXPORT_SYMBOL(snd_timer_resolution);
 445
 446 static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
 447 {
 448         struct snd_timer *timer;
 449         unsigned long resolution = 0;
 450         struct snd_timer_instance *ts;
 451         struct timespec tstamp;
 452
 453         if (timer_tstamp_monotonic)
 454                 ktime_get_ts(&tstamp);
 455         else
 456                 getnstimeofday(&tstamp);
 457         if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
 458                        event > SNDRV_TIMER_EVENT_PAUSE))
 459                 return;
 460         if (event == SNDRV_TIMER_EVENT_START ||
 461             event == SNDRV_TIMER_EVENT_CONTINUE)
 462                 resolution = snd_timer_resolution(ti);
 463         if (ti->ccallback)
 464                 ti->ccallback(ti, event, &tstamp, resolution);
 465         if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
 466                 return;
 467         timer = ti->timer;
 468         if (timer == NULL)
 469                 return;
 470         if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 471                 return;
 472         list_for_each_entry(ts, &ti->slave_active_head, active_list)
 473                 if (ts->ccallback)
 474                         ts->ccallback(ts, event + 100, &tstamp, resolution);
 475 }
 476
 477 /* start/continue a master timer */
 478 static int snd_timer_start1(struct snd_timer_instance *timeri,
 479                             bool start, unsigned long ticks)
 480 {
 481         struct snd_timer *timer;
 482         int result;
 483         unsigned long flags;
 484
 485         timer = timeri->timer;
 486         if (!timer)
 487                 return -EINVAL;
 488
 489         spin_lock_irqsave(&timer->lock, flags);
 490         if (timer->card && timer->card->shutdown) {
 491                 result = -ENODEV;
 492                 goto unlock;
 493         }
 494         if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 495                              SNDRV_TIMER_IFLG_START)) {
 496                 result = -EBUSY;
 497                 goto unlock;
 498         }
 499
 500         if (start)
 501                 timeri->ticks = timeri->cticks = ticks;
 502         else if (!timeri->cticks)
 503                 timeri->cticks = 1;
 504         timeri->pticks = 0;
 505
 506         list_move_tail(&timeri->active_list, &timer->active_list_head);
 507         if (timer->running) {
 508                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 509                         goto __start_now;
 510                 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
 511                 timeri->flags |= SNDRV_TIMER_IFLG_START;
 512                 result = 1; /* delayed start */
 513         } else {
 514                 if (start)
 515                         timer->sticks = ticks;
 516                 timer->hw.start(timer);
 517               __start_now:
 518                 timer->running++;
 519                 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 520                 result = 0;
 521         }
 522         snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 523                           SNDRV_TIMER_EVENT_CONTINUE);
 524  unlock:
 525         spin_unlock_irqrestore(&timer->lock, flags);
 526         return result;
 527 }
 528
 529 /* start/continue a slave timer */
 530 static int snd_timer_start_slave(struct snd_timer_instance *timeri,
 531                                  bool start)
 532 {
 533         unsigned long flags;
 534
 535         spin_lock_irqsave(&slave_active_lock, flags);
 536         if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) {
 537                 spin_unlock_irqrestore(&slave_active_lock, flags);
 538                 return -EBUSY;
 539         }
 540         timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 541         if (timeri->master && timeri->timer) {
 542                 spin_lock(&timeri->timer->lock);
 543                 list_add_tail(&timeri->active_list,
 544                               &timeri->master->slave_active_head);
 545                 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 546                                   SNDRV_TIMER_EVENT_CONTINUE);
 547                 spin_unlock(&timeri->timer->lock);
 548         }
 549         spin_unlock_irqrestore(&slave_active_lock, flags);
 550         return 1; /* delayed start */
 551 }
 552
 553 /* stop/pause a master timer */
 554 static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
 555 {
 556         struct snd_timer *timer;
 557         int result = 0;
 558         unsigned long flags;
 559
 560         timer = timeri->timer;
 561         if (!timer)
 562                 return -EINVAL;
 563         spin_lock_irqsave(&timer->lock, flags);
 564         if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 565                                SNDRV_TIMER_IFLG_START))) {
 566                 result = -EBUSY;
 567                 goto unlock;
 568         }
 569         list_del_init(&timeri->ack_list);
 570         list_del_init(&timeri->active_list);
 571         if (timer->card && timer->card->shutdown)
 572                 goto unlock;
 573         if (stop) {
 574                 timeri->cticks = timeri->ticks;
 575                 timeri->pticks = 0;
 576         }
 577         if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
 578             !(--timer->running)) {
 579                 timer->hw.stop(timer);
 580                 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
 581                         timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 582                         snd_timer_reschedule(timer, 0);
 583                         if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
 584                                 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 585                                 timer->hw.start(timer);
 586                         }
 587                 }
 588         }
 589         timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
 590         if (stop)
 591                 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
 592         else
 593                 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
 594         snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 595                           SNDRV_TIMER_EVENT_CONTINUE);
 596  unlock:
 597         spin_unlock_irqrestore(&timer->lock, flags);
 598         return result;
 599 }
 600
 601 /* stop/pause a slave timer */
 602 static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
 603 {
 604         unsigned long flags;
 605
 606         spin_lock_irqsave(&slave_active_lock, flags);
 607         if (!(timeri->flags & SNDRV_TIMER_IFLG_RUNNING)) {
 608                 spin_unlock_irqrestore(&slave_active_lock, flags);
 609                 return -EBUSY;
 610         }
 611         timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 612         if (timeri->timer) {
 613                 spin_lock(&timeri->timer->lock);
 614                 list_del_init(&timeri->ack_list);
 615                 list_del_init(&timeri->active_list);
 616                 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 617                                   SNDRV_TIMER_EVENT_CONTINUE);
 618                 spin_unlock(&timeri->timer->lock);
 619         }
 620         spin_unlock_irqrestore(&slave_active_lock, flags);
 621         return 0;
 622 }
 623
 624 /*
 625  *  start the timer instance
 626  */
 627 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
 628 {
 629         if (timeri == NULL || ticks < 1)
 630                 return -EINVAL;
 631         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 632                 return snd_timer_start_slave(timeri, true);
 633         else
 634                 return snd_timer_start1(timeri, true, ticks);
 635 }
 636 EXPORT_SYMBOL(snd_timer_start);
 637
 638 /*
 639  * stop the timer instance.
 640  *
 641  * do not call this from the timer callback!
 642  */
 643 int snd_timer_stop(struct snd_timer_instance *timeri)
 644 {
 645         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 646                 return snd_timer_stop_slave(timeri, true);
 647         else
 648                 return snd_timer_stop1(timeri, true);
 649 }
 650 EXPORT_SYMBOL(snd_timer_stop);
 651
 652 /*
 653  * start again..  the tick is kept.
 654  */
 655 int snd_timer_continue(struct snd_timer_instance *timeri)
 656 {
 657         /* timer can continue only after pause */
 658         if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
 659                 return -EINVAL;
 660
 661         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 662                 return snd_timer_start_slave(timeri, false);
 663         else
 664                 return snd_timer_start1(timeri, false, 0);
 665 }
 666 EXPORT_SYMBOL(snd_timer_continue);
 667
 668 /*
 669  * pause.. remember the ticks left
 670  */
 671 int snd_timer_pause(struct snd_timer_instance * timeri)
 672 {
 673         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 674                 return snd_timer_stop_slave(timeri, false);
 675         else
 676                 return snd_timer_stop1(timeri, false);
 677 }
 678 EXPORT_SYMBOL(snd_timer_pause);
 679
 680 /*
 681  * reschedule the timer
 682  *
 683  * start pending instances and check the scheduling ticks.
 684  * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
 685  */
 686 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
 687 {
 688         struct snd_timer_instance *ti;
 689         unsigned long ticks = ~0UL;
 690
 691         list_for_each_entry(ti, &timer->active_list_head, active_list) {
 692                 if (ti->flags & SNDRV_TIMER_IFLG_START) {
 693                         ti->flags &= ~SNDRV_TIMER_IFLG_START;
 694                         ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
 695                         timer->running++;
 696                 }
 697                 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
 698                         if (ticks > ti->cticks)
 699                                 ticks = ti->cticks;
 700                 }
 701         }
 702         if (ticks == ~0UL) {
 703                 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 704                 return;
 705         }
 706         if (ticks > timer->hw.ticks)
 707                 ticks = timer->hw.ticks;
 708         if (ticks_left != ticks)
 709                 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 710         timer->sticks = ticks;
 711 }
 712
 713 /*
 714  * timer tasklet
 715  *
 716  */
 717 static void snd_timer_tasklet(unsigned long arg)
 718 {
 719         struct snd_timer *timer = (struct snd_timer *) arg;
 720         struct snd_timer_instance *ti;
 721         struct list_head *p;
 722         unsigned long resolution, ticks;
 723         unsigned long flags;
 724
 725         if (timer->card && timer->card->shutdown)
 726                 return;
 727
 728         spin_lock_irqsave(&timer->lock, flags);
 729         /* now process all callbacks */
 730         while (!list_empty(&timer->sack_list_head)) {
 731                 p = timer->sack_list_head.next;         /* get first item */
 732                 ti = list_entry(p, struct snd_timer_instance, ack_list);
 733
 734                 /* remove from ack_list and make empty */
 735                 list_del_init(p);
 736
 737                 ticks = ti->pticks;
 738                 ti->pticks = 0;
 739                 resolution = ti->resolution;
 740
 741                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 742                 spin_unlock(&timer->lock);
 743                 if (ti->callback)
 744                         ti->callback(ti, resolution, ticks);
 745                 spin_lock(&timer->lock);
 746                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 747         }
 748         spin_unlock_irqrestore(&timer->lock, flags);
 749 }
 750
 751 /*
 752  * timer interrupt
 753  *
 754  * ticks_left is usually equal to timer->sticks.
 755  *
 756  */
 757 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
 758 {
 759         struct snd_timer_instance *ti, *ts, *tmp;
 760         unsigned long resolution, ticks;
 761         struct list_head *p, *ack_list_head;
 762         unsigned long flags;
 763         int use_tasklet = 0;
 764
 765         if (timer == NULL)
 766                 return;
 767
 768         if (timer->card && timer->card->shutdown)
 769                 return;
 770
 771         spin_lock_irqsave(&timer->lock, flags);
 772
 773         /* remember the current resolution */
 774         if (timer->hw.c_resolution)
 775                 resolution = timer->hw.c_resolution(timer);
 776         else
 777                 resolution = timer->hw.resolution;
 778
 779         /* loop for all active instances
 780          * Here we cannot use list_for_each_entry because the active_list of a
 781          * processed instance is relinked to done_list_head before the callback
 782          * is called.
 783          */
 784         list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
 785                                  active_list) {
 786                 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
 787                         continue;
 788                 ti->pticks += ticks_left;
 789                 ti->resolution = resolution;
 790                 if (ti->cticks < ticks_left)
 791                         ti->cticks = 0;
 792                 else
 793                         ti->cticks -= ticks_left;
 794                 if (ti->cticks) /* not expired */
 795                         continue;
 796                 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
 797                         ti->cticks = ti->ticks;
 798                 } else {
 799                         ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 800                         --timer->running;
 801                         list_del_init(&ti->active_list);
 802                 }
 803                 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
 804                     (ti->flags & SNDRV_TIMER_IFLG_FAST))
 805                         ack_list_head = &timer->ack_list_head;
 806                 else
 807                         ack_list_head = &timer->sack_list_head;
 808                 if (list_empty(&ti->ack_list))
 809                         list_add_tail(&ti->ack_list, ack_list_head);
 810                 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
 811                         ts->pticks = ti->pticks;
 812                         ts->resolution = resolution;
 813                         if (list_empty(&ts->ack_list))
 814                                 list_add_tail(&ts->ack_list, ack_list_head);
 815                 }
 816         }
 817         if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
 818                 snd_timer_reschedule(timer, timer->sticks);
 819         if (timer->running) {
 820                 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
 821                         timer->hw.stop(timer);
 822                         timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 823                 }
 824                 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
 825                     (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
 826                         /* restart timer */
 827                         timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 828                         timer->hw.start(timer);
 829                 }
 830         } else {
 831                 timer->hw.stop(timer);
 832         }
 833
 834         /* now process all fast callbacks */
 835         while (!list_empty(&timer->ack_list_head)) {
 836                 p = timer->ack_list_head.next;          /* get first item */
 837                 ti = list_entry(p, struct snd_timer_instance, ack_list);
 838
 839                 /* remove from ack_list and make empty */
 840                 list_del_init(p);
 841
 842                 ticks = ti->pticks;
 843                 ti->pticks = 0;
 844
 845                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 846                 spin_unlock(&timer->lock);
 847                 if (ti->callback)
 848                         ti->callback(ti, resolution, ticks);
 849                 spin_lock(&timer->lock);
 850                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 851         }
 852
 853         /* do we have any slow callbacks? */
 854         use_tasklet = !list_empty(&timer->sack_list_head);
 855         spin_unlock_irqrestore(&timer->lock, flags);
 856
 857         if (use_tasklet)
 858                 tasklet_schedule(&timer->task_queue);
 859 }
 860 EXPORT_SYMBOL(snd_timer_interrupt);
 861
 862 /*
 863
 864  */
 865
 866 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
 867                   struct snd_timer **rtimer)
 868 {
 869         struct snd_timer *timer;
 870         int err;
 871         static struct snd_device_ops ops = {
 872                 .dev_free = snd_timer_dev_free,
 873                 .dev_register = snd_timer_dev_register,
 874                 .dev_disconnect = snd_timer_dev_disconnect,
 875         };
 876
 877         if (snd_BUG_ON(!tid))
 878                 return -EINVAL;
 879         if (rtimer)
 880                 *rtimer = NULL;
 881         timer = kzalloc(sizeof(*timer), GFP_KERNEL);
 882         if (!timer)
 883                 return -ENOMEM;
 884         timer->tmr_class = tid->dev_class;
 885         timer->card = card;
 886         timer->tmr_device = tid->device;
 887         timer->tmr_subdevice = tid->subdevice;
 888         if (id)
 889                 strlcpy(timer->id, id, sizeof(timer->id));
 890         timer->sticks = 1;
 891         INIT_LIST_HEAD(&timer->device_list);
 892         INIT_LIST_HEAD(&timer->open_list_head);
 893         INIT_LIST_HEAD(&timer->active_list_head);
 894         INIT_LIST_HEAD(&timer->ack_list_head);
 895         INIT_LIST_HEAD(&timer->sack_list_head);
 896         spin_lock_init(&timer->lock);
 897         tasklet_init(&timer->task_queue, snd_timer_tasklet,
 898                      (unsigned long)timer);
 899         timer->max_instances = 1000; /* default limit per timer */
 900         if (card != NULL) {
 901                 timer->module = card->module;
 902                 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
 903                 if (err < 0) {
 904                         snd_timer_free(timer);
 905                         return err;
 906                 }
 907         }
 908         if (rtimer)
 909                 *rtimer = timer;
 910         return 0;
 911 }
 912 EXPORT_SYMBOL(snd_timer_new);
 913
 914 static int snd_timer_free(struct snd_timer *timer)
 915 {
 916         if (!timer)
 917                 return 0;
 918
 919         mutex_lock(&register_mutex);
 920         if (! list_empty(&timer->open_list_head)) {
 921                 struct list_head *p, *n;
 922                 struct snd_timer_instance *ti;
 923                 pr_warn("ALSA: timer %p is busy?\n", timer);
 924                 list_for_each_safe(p, n, &timer->open_list_head) {
 925                         list_del_init(p);
 926                         ti = list_entry(p, struct snd_timer_instance, open_list);
 927                         ti->timer = NULL;
 928                 }
 929         }
 930         list_del(&timer->device_list);
 931         mutex_unlock(&register_mutex);
 932
 933         if (timer->private_free)
 934                 timer->private_free(timer);
 935         kfree(timer);
 936         return 0;
 937 }
 938
 939 static int snd_timer_dev_free(struct snd_device *device)
 940 {
 941         struct snd_timer *timer = device->device_data;
 942         return snd_timer_free(timer);
 943 }
 944
 945 static int snd_timer_dev_register(struct snd_device *dev)
 946 {
 947         struct snd_timer *timer = dev->device_data;
 948         struct snd_timer *timer1;
 949
 950         if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
 951                 return -ENXIO;
 952         if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
 953             !timer->hw.resolution && timer->hw.c_resolution == NULL)
 954                 return -EINVAL;
 955
 956         mutex_lock(&register_mutex);
 957         list_for_each_entry(timer1, &snd_timer_list, device_list) {
 958                 if (timer1->tmr_class > timer->tmr_class)
 959                         break;
 960                 if (timer1->tmr_class < timer->tmr_class)
 961                         continue;
 962                 if (timer1->card && timer->card) {
 963                         if (timer1->card->number > timer->card->number)
 964                                 break;
 965                         if (timer1->card->number < timer->card->number)
 966                                 continue;
 967                 }
 968                 if (timer1->tmr_device > timer->tmr_device)
 969                         break;
 970                 if (timer1->tmr_device < timer->tmr_device)
 971                         continue;
 972                 if (timer1->tmr_subdevice > timer->tmr_subdevice)
 973                         break;
 974                 if (timer1->tmr_subdevice < timer->tmr_subdevice)
 975                         continue;
 976                 /* conflicts.. */
 977                 mutex_unlock(&register_mutex);
 978                 return -EBUSY;
 979         }
 980         list_add_tail(&timer->device_list, &timer1->device_list);
 981         mutex_unlock(&register_mutex);
 982         return 0;
 983 }
 984
 985 static int snd_timer_dev_disconnect(struct snd_device *device)
 986 {
 987         struct snd_timer *timer = device->device_data;
 988         struct snd_timer_instance *ti;
 989
 990         mutex_lock(&register_mutex);
 991         list_del_init(&timer->device_list);
 992         /* wake up pending sleepers */
 993         list_for_each_entry(ti, &timer->open_list_head, open_list) {
 994                 if (ti->disconnect)
 995                         ti->disconnect(ti);
 996         }
 997         mutex_unlock(&register_mutex);
 998         return 0;
 999 }
1000
1001 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
1002 {
1003         unsigned long flags;
1004         unsigned long resolution = 0;
1005         struct snd_timer_instance *ti, *ts;
1006
1007         if (timer->card && timer->card->shutdown)
1008                 return;
1009         if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
1010                 return;
1011         if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
1012                        event > SNDRV_TIMER_EVENT_MRESUME))
1013                 return;
1014         spin_lock_irqsave(&timer->lock, flags);
1015         if (event == SNDRV_TIMER_EVENT_MSTART ||
1016             event == SNDRV_TIMER_EVENT_MCONTINUE ||
1017             event == SNDRV_TIMER_EVENT_MRESUME) {
1018                 if (timer->hw.c_resolution)
1019                         resolution = timer->hw.c_resolution(timer);
1020                 else
1021                         resolution = timer->hw.resolution;
1022         }
1023         list_for_each_entry(ti, &timer->active_list_head, active_list) {
1024                 if (ti->ccallback)
1025                         ti->ccallback(ti, event, tstamp, resolution);
1026                 list_for_each_entry(ts, &ti->slave_active_head, active_list)
1027                         if (ts->ccallback)
1028                                 ts->ccallback(ts, event, tstamp, resolution);
1029         }
1030         spin_unlock_irqrestore(&timer->lock, flags);
1031 }
1032 EXPORT_SYMBOL(snd_timer_notify);
1033
1034 /*
1035  * exported functions for global timers
1036  */
1037 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
1038 {
1039         struct snd_timer_id tid;
1040
1041         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
1042         tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1043         tid.card = -1;
1044         tid.device = device;
1045         tid.subdevice = 0;
1046         return snd_timer_new(NULL, id, &tid, rtimer);
1047 }
1048 EXPORT_SYMBOL(snd_timer_global_new);
1049
1050 int snd_timer_global_free(struct snd_timer *timer)
1051 {
1052         return snd_timer_free(timer);
1053 }
1054 EXPORT_SYMBOL(snd_timer_global_free);
1055
1056 int snd_timer_global_register(struct snd_timer *timer)
1057 {
1058         struct snd_device dev;
1059
1060         memset(&dev, 0, sizeof(dev));
1061         dev.device_data = timer;
1062         return snd_timer_dev_register(&dev);
1063 }
1064 EXPORT_SYMBOL(snd_timer_global_register);
1065
1066 /*
1067  *  System timer
1068  */
1069
1070 struct snd_timer_system_private {
1071         struct timer_list tlist;
1072         struct snd_timer *snd_timer;
1073         unsigned long last_expires;
1074         unsigned long last_jiffies;
1075         unsigned long correction;
1076 };
1077
1078 static void snd_timer_s_function(struct timer_list *t)
1079 {
1080         struct snd_timer_system_private *priv = from_timer(priv, t,
1081                                                                 tlist);
1082         struct snd_timer *timer = priv->snd_timer;
1083         unsigned long jiff = jiffies;
1084         if (time_after(jiff, priv->last_expires))
1085                 priv->correction += (long)jiff - (long)priv->last_expires;
1086         snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1087 }
1088
1089 static int snd_timer_s_start(struct snd_timer * timer)
1090 {
1091         struct snd_timer_system_private *priv;
1092         unsigned long njiff;
1093
1094         priv = (struct snd_timer_system_private *) timer->private_data;
1095         njiff = (priv->last_jiffies = jiffies);
1096         if (priv->correction > timer->sticks - 1) {
1097                 priv->correction -= timer->sticks - 1;
1098                 njiff++;
1099         } else {
1100                 njiff += timer->sticks - priv->correction;
1101                 priv->correction = 0;
1102         }
1103         priv->last_expires = njiff;
1104         mod_timer(&priv->tlist, njiff);
1105         return 0;
1106 }
1107
1108 static int snd_timer_s_stop(struct snd_timer * timer)
1109 {
1110         struct snd_timer_system_private *priv;
1111         unsigned long jiff;
1112
1113         priv = (struct snd_timer_system_private *) timer->private_data;
1114         del_timer(&priv->tlist);
1115         jiff = jiffies;
1116         if (time_before(jiff, priv->last_expires))
1117                 timer->sticks = priv->last_expires - jiff;
1118         else
1119                 timer->sticks = 1;
1120         priv->correction = 0;
1121         return 0;
1122 }
1123
1124 static int snd_timer_s_close(struct snd_timer *timer)
1125 {
1126         struct snd_timer_system_private *priv;
1127
1128         priv = (struct snd_timer_system_private *)timer->private_data;
1129         del_timer_sync(&priv->tlist);
1130         return 0;
1131 }
1132
1133 static struct snd_timer_hardware snd_timer_system =
1134 {
1135         .flags =        SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
1136         .resolution =   1000000000L / HZ,
1137         .ticks =        10000000L,
1138         .close =        snd_timer_s_close,
1139         .start =        snd_timer_s_start,
1140         .stop =         snd_timer_s_stop
1141 };
1142
1143 static void snd_timer_free_system(struct snd_timer *timer)
1144 {
1145         kfree(timer->private_data);
1146 }
1147
1148 static int snd_timer_register_system(void)
1149 {
1150         struct snd_timer *timer;
1151         struct snd_timer_system_private *priv;
1152         int err;
1153
1154         err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1155         if (err < 0)
1156                 return err;
1157         strcpy(timer->name, "system timer");
1158         timer->hw = snd_timer_system;
1159         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1160         if (priv == NULL) {
1161                 snd_timer_free(timer);
1162                 return -ENOMEM;
1163         }
1164         priv->snd_timer = timer;
1165         timer_setup(&priv->tlist, snd_timer_s_function, 0);
1166         timer->private_data = priv;
1167         timer->private_free = snd_timer_free_system;
1168         return snd_timer_global_register(timer);
1169 }
1170
1171 #ifdef CONFIG_SND_PROC_FS
1172 /*
1173  *  Info interface
1174  */
1175
1176 static void snd_timer_proc_read(struct snd_info_entry *entry,
1177                                 struct snd_info_buffer *buffer)
1178 {
1179         struct snd_timer *timer;
1180         struct snd_timer_instance *ti;
1181
1182         mutex_lock(&register_mutex);
1183         list_for_each_entry(timer, &snd_timer_list, device_list) {
1184                 if (timer->card && timer->card->shutdown)
1185                         continue;
1186                 switch (timer->tmr_class) {
1187                 case SNDRV_TIMER_CLASS_GLOBAL:
1188                         snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1189                         break;
1190                 case SNDRV_TIMER_CLASS_CARD:
1191                         snd_iprintf(buffer, "C%i-%i: ",
1192                                     timer->card->number, timer->tmr_device);
1193                         break;
1194                 case SNDRV_TIMER_CLASS_PCM:
1195                         snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1196                                     timer->tmr_device, timer->tmr_subdevice);
1197                         break;
1198                 default:
1199                         snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1200                                     timer->card ? timer->card->number : -1,
1201                                     timer->tmr_device, timer->tmr_subdevice);
1202                 }
1203                 snd_iprintf(buffer, "%s :", timer->name);
1204                 if (timer->hw.resolution)
1205                         snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1206                                     timer->hw.resolution / 1000,
1207                                     timer->hw.resolution % 1000,
1208                                     timer->hw.ticks);
1209                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1210                         snd_iprintf(buffer, " SLAVE");
1211                 snd_iprintf(buffer, "\n");
1212                 list_for_each_entry(ti, &timer->open_list_head, open_list)
1213                         snd_iprintf(buffer, "  Client %s : %s\n",
1214                                     ti->owner ? ti->owner : "unknown",
1215                                     ti->flags & (SNDRV_TIMER_IFLG_START |
1216                                                  SNDRV_TIMER_IFLG_RUNNING)
1217                                     ? "running" : "stopped");
1218         }
1219         mutex_unlock(&register_mutex);
1220 }
1221
1222 static struct snd_info_entry *snd_timer_proc_entry;
1223
1224 static void __init snd_timer_proc_init(void)
1225 {
1226         struct snd_info_entry *entry;
1227
1228         entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1229         if (entry != NULL) {
1230                 entry->c.text.read = snd_timer_proc_read;
1231                 if (snd_info_register(entry) < 0) {
1232                         snd_info_free_entry(entry);
1233                         entry = NULL;
1234                 }
1235         }
1236         snd_timer_proc_entry = entry;
1237 }
1238
1239 static void __exit snd_timer_proc_done(void)
1240 {
1241         snd_info_free_entry(snd_timer_proc_entry);
1242 }
1243 #else /* !CONFIG_SND_PROC_FS */
1244 #define snd_timer_proc_init()
1245 #define snd_timer_proc_done()
1246 #endif
1247
1248 /*
1249  *  USER SPACE interface
1250  */
1251
1252 static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1253                                      unsigned long resolution,
1254                                      unsigned long ticks)
1255 {
1256         struct snd_timer_user *tu = timeri->callback_data;
1257         struct snd_timer_read *r;
1258         int prev;
1259
1260         spin_lock(&tu->qlock);
1261         if (tu->qused > 0) {
1262                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1263                 r = &tu->queue[prev];
1264                 if (r->resolution == resolution) {
1265                         r->ticks += ticks;
1266                         goto __wake;
1267                 }
1268         }
1269         if (tu->qused >= tu->queue_size) {
1270                 tu->overrun++;
1271         } else {
1272                 r = &tu->queue[tu->qtail++];
1273                 tu->qtail %= tu->queue_size;
1274                 r->resolution = resolution;
1275                 r->ticks = ticks;
1276                 tu->qused++;
1277         }
1278       __wake:
1279         spin_unlock(&tu->qlock);
1280         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1281         wake_up(&tu->qchange_sleep);
1282 }
1283
1284 static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1285                                             struct snd_timer_tread *tread)
1286 {
1287         if (tu->qused >= tu->queue_size) {
1288                 tu->overrun++;
1289         } else {
1290                 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1291                 tu->qtail %= tu->queue_size;
1292                 tu->qused++;
1293         }
1294 }
1295
1296 static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1297                                      int event,
1298                                      struct timespec *tstamp,
1299                                      unsigned long resolution)
1300 {
1301         struct snd_timer_user *tu = timeri->callback_data;
1302         struct snd_timer_tread r1;
1303         unsigned long flags;
1304
1305         if (event >= SNDRV_TIMER_EVENT_START &&
1306             event <= SNDRV_TIMER_EVENT_PAUSE)
1307                 tu->tstamp = *tstamp;
1308         if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1309                 return;
1310         memset(&r1, 0, sizeof(r1));
1311         r1.event = event;
1312         r1.tstamp = *tstamp;
1313         r1.val = resolution;
1314         spin_lock_irqsave(&tu->qlock, flags);
1315         snd_timer_user_append_to_tqueue(tu, &r1);
1316         spin_unlock_irqrestore(&tu->qlock, flags);
1317         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1318         wake_up(&tu->qchange_sleep);
1319 }
1320
1321 static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1322 {
1323         struct snd_timer_user *tu = timeri->callback_data;
1324
1325         tu->disconnected = true;
1326         wake_up(&tu->qchange_sleep);
1327 }
1328
1329 static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1330                                       unsigned long resolution,
1331                                       unsigned long ticks)
1332 {
1333         struct snd_timer_user *tu = timeri->callback_data;
1334         struct snd_timer_tread *r, r1;
1335         struct timespec tstamp;
1336         int prev, append = 0;
1337
1338         memset(&r1, 0, sizeof(r1));
1339         memset(&tstamp, 0, sizeof(tstamp));
1340         spin_lock(&tu->qlock);
1341         if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1342                            (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1343                 spin_unlock(&tu->qlock);
1344                 return;
1345         }
1346         if (tu->last_resolution != resolution || ticks > 0) {
1347                 if (timer_tstamp_monotonic)
1348                         ktime_get_ts(&tstamp);
1349                 else
1350                         getnstimeofday(&tstamp);
1351         }
1352         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1353             tu->last_resolution != resolution) {
1354                 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1355                 r1.tstamp = tstamp;
1356                 r1.val = resolution;
1357                 snd_timer_user_append_to_tqueue(tu, &r1);
1358                 tu->last_resolution = resolution;
1359                 append++;
1360         }
1361         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1362                 goto __wake;
1363         if (ticks == 0)
1364                 goto __wake;
1365         if (tu->qused > 0) {
1366                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1367                 r = &tu->tqueue[prev];
1368                 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1369                         r->tstamp = tstamp;
1370                         r->val += ticks;
1371                         append++;
1372                         goto __wake;
1373                 }
1374         }
1375         r1.event = SNDRV_TIMER_EVENT_TICK;
1376         r1.tstamp = tstamp;
1377         r1.val = ticks;
1378         snd_timer_user_append_to_tqueue(tu, &r1);
1379         append++;
1380       __wake:
1381         spin_unlock(&tu->qlock);
1382         if (append == 0)
1383                 return;
1384         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1385         wake_up(&tu->qchange_sleep);
1386 }
1387
1388 static int realloc_user_queue(struct snd_timer_user *tu, int size)
1389 {
1390         struct snd_timer_read *queue = NULL;
1391         struct snd_timer_tread *tqueue = NULL;
1392
1393         if (tu->tread) {
1394                 tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL);
1395                 if (!tqueue)
1396                         return -ENOMEM;
1397         } else {
1398                 queue = kcalloc(size, sizeof(*queue), GFP_KERNEL);
1399                 if (!queue)
1400                         return -ENOMEM;
1401         }
1402
1403         spin_lock_irq(&tu->qlock);
1404         kfree(tu->queue);
1405         kfree(tu->tqueue);
1406         tu->queue_size = size;
1407         tu->queue = queue;
1408         tu->tqueue = tqueue;
1409         tu->qhead = tu->qtail = tu->qused = 0;
1410         spin_unlock_irq(&tu->qlock);
1411
1412         return 0;
1413 }
1414
1415 static int snd_timer_user_open(struct inode *inode, struct file *file)
1416 {
1417         struct snd_timer_user *tu;
1418         int err;
1419
1420         err = nonseekable_open(inode, file);
1421         if (err < 0)
1422                 return err;
1423
1424         tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1425         if (tu == NULL)
1426                 return -ENOMEM;
1427         spin_lock_init(&tu->qlock);
1428         init_waitqueue_head(&tu->qchange_sleep);
1429         mutex_init(&tu->ioctl_lock);
1430         tu->ticks = 1;
1431         if (realloc_user_queue(tu, 128) < 0) {
1432                 kfree(tu);
1433                 return -ENOMEM;
1434         }
1435         file->private_data = tu;
1436         return 0;
1437 }
1438
1439 static int snd_timer_user_release(struct inode *inode, struct file *file)
1440 {
1441         struct snd_timer_user *tu;
1442
1443         if (file->private_data) {
1444                 tu = file->private_data;
1445                 file->private_data = NULL;
1446                 mutex_lock(&tu->ioctl_lock);
1447                 if (tu->timeri)
1448                         snd_timer_close(tu->timeri);
1449                 mutex_unlock(&tu->ioctl_lock);
1450                 kfree(tu->queue);
1451                 kfree(tu->tqueue);
1452                 kfree(tu);
1453         }
1454         return 0;
1455 }
1456
1457 static void snd_timer_user_zero_id(struct snd_timer_id *id)
1458 {
1459         id->dev_class = SNDRV_TIMER_CLASS_NONE;
1460         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1461         id->card = -1;
1462         id->device = -1;
1463         id->subdevice = -1;
1464 }
1465
1466 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1467 {
1468         id->dev_class = timer->tmr_class;
1469         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1470         id->card = timer->card ? timer->card->number : -1;
1471         id->device = timer->tmr_device;
1472         id->subdevice = timer->tmr_subdevice;
1473 }
1474
1475 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1476 {
1477         struct snd_timer_id id;
1478         struct snd_timer *timer;
1479         struct list_head *p;
1480
1481         if (copy_from_user(&id, _tid, sizeof(id)))
1482                 return -EFAULT;
1483         mutex_lock(&register_mutex);
1484         if (id.dev_class < 0) {         /* first item */
1485                 if (list_empty(&snd_timer_list))
1486                         snd_timer_user_zero_id(&id);
1487                 else {
1488                         timer = list_entry(snd_timer_list.next,
1489                                            struct snd_timer, device_list);
1490                         snd_timer_user_copy_id(&id, timer);
1491                 }
1492         } else {
1493                 switch (id.dev_class) {
1494                 case SNDRV_TIMER_CLASS_GLOBAL:
1495                         id.device = id.device < 0 ? 0 : id.device + 1;
1496                         list_for_each(p, &snd_timer_list) {
1497                                 timer = list_entry(p, struct snd_timer, device_list);
1498                                 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1499                                         snd_timer_user_copy_id(&id, timer);
1500                                         break;
1501                                 }
1502                                 if (timer->tmr_device >= id.device) {
1503                                         snd_timer_user_copy_id(&id, timer);
1504                                         break;
1505                                 }
1506                         }
1507                         if (p == &snd_timer_list)
1508                                 snd_timer_user_zero_id(&id);
1509                         break;
1510                 case SNDRV_TIMER_CLASS_CARD:
1511                 case SNDRV_TIMER_CLASS_PCM:
1512                         if (id.card < 0) {
1513                                 id.card = 0;
1514                         } else {
1515                                 if (id.device < 0) {
1516                                         id.device = 0;
1517                                 } else {
1518                                         if (id.subdevice < 0)
1519                                                 id.subdevice = 0;
1520                                         else
1521                                                 id.subdevice++;
1522                                 }
1523                         }
1524                         list_for_each(p, &snd_timer_list) {
1525                                 timer = list_entry(p, struct snd_timer, device_list);
1526                                 if (timer->tmr_class > id.dev_class) {
1527                                         snd_timer_user_copy_id(&id, timer);
1528                                         break;
1529                                 }
1530                                 if (timer->tmr_class < id.dev_class)
1531                                         continue;
1532                                 if (timer->card->number > id.card) {
1533                                         snd_timer_user_copy_id(&id, timer);
1534                                         break;
1535                                 }
1536                                 if (timer->card->number < id.card)
1537                                         continue;
1538                                 if (timer->tmr_device > id.device) {
1539                                         snd_timer_user_copy_id(&id, timer);
1540                                         break;
1541                                 }
1542                                 if (timer->tmr_device < id.device)
1543                                         continue;
1544                                 if (timer->tmr_subdevice > id.subdevice) {
1545                                         snd_timer_user_copy_id(&id, timer);
1546                                         break;
1547                                 }
1548                                 if (timer->tmr_subdevice < id.subdevice)
1549                                         continue;
1550                                 snd_timer_user_copy_id(&id, timer);
1551                                 break;
1552                         }
1553                         if (p == &snd_timer_list)
1554                                 snd_timer_user_zero_id(&id);
1555                         break;
1556                 default:
1557                         snd_timer_user_zero_id(&id);
1558                 }
1559         }
1560         mutex_unlock(&register_mutex);
1561         if (copy_to_user(_tid, &id, sizeof(*_tid)))
1562                 return -EFAULT;
1563         return 0;
1564 }
1565
1566 static int snd_timer_user_ginfo(struct file *file,
1567                                 struct snd_timer_ginfo __user *_ginfo)
1568 {
1569         struct snd_timer_ginfo *ginfo;
1570         struct snd_timer_id tid;
1571         struct snd_timer *t;
1572         struct list_head *p;
1573         int err = 0;
1574
1575         ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1576         if (IS_ERR(ginfo))
1577                 return PTR_ERR(ginfo);
1578
1579         tid = ginfo->tid;
1580         memset(ginfo, 0, sizeof(*ginfo));
1581         ginfo->tid = tid;
1582         mutex_lock(&register_mutex);
1583         t = snd_timer_find(&tid);
1584         if (t != NULL) {
1585                 ginfo->card = t->card ? t->card->number : -1;
1586                 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1587                         ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1588                 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1589                 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1590                 ginfo->resolution = t->hw.resolution;
1591                 if (t->hw.resolution_min > 0) {
1592                         ginfo->resolution_min = t->hw.resolution_min;
1593                         ginfo->resolution_max = t->hw.resolution_max;
1594                 }
1595                 list_for_each(p, &t->open_list_head) {
1596                         ginfo->clients++;
1597                 }
1598         } else {
1599                 err = -ENODEV;
1600         }
1601         mutex_unlock(&register_mutex);
1602         if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1603                 err = -EFAULT;
1604         kfree(ginfo);
1605         return err;
1606 }
1607
1608 static int timer_set_gparams(struct snd_timer_gparams *gparams)
1609 {
1610         struct snd_timer *t;
1611         int err;
1612
1613         mutex_lock(&register_mutex);
1614         t = snd_timer_find(&gparams->tid);
1615         if (!t) {
1616                 err = -ENODEV;
1617                 goto _error;
1618         }
1619         if (!list_empty(&t->open_list_head)) {
1620                 err = -EBUSY;
1621                 goto _error;
1622         }
1623         if (!t->hw.set_period) {
1624                 err = -ENOSYS;
1625                 goto _error;
1626         }
1627         err = t->hw.set_period(t, gparams->period_num, gparams->period_den);
1628 _error:
1629         mutex_unlock(&register_mutex);
1630         return err;
1631 }
1632
1633 static int snd_timer_user_gparams(struct file *file,
1634                                   struct snd_timer_gparams __user *_gparams)
1635 {
1636         struct snd_timer_gparams gparams;
1637
1638         if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1639                 return -EFAULT;
1640         return timer_set_gparams(&gparams);
1641 }
1642
1643 static int snd_timer_user_gstatus(struct file *file,
1644                                   struct snd_timer_gstatus __user *_gstatus)
1645 {
1646         struct snd_timer_gstatus gstatus;
1647         struct snd_timer_id tid;
1648         struct snd_timer *t;
1649         int err = 0;
1650
1651         if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1652                 return -EFAULT;
1653         tid = gstatus.tid;
1654         memset(&gstatus, 0, sizeof(gstatus));
1655         gstatus.tid = tid;
1656         mutex_lock(&register_mutex);
1657         t = snd_timer_find(&tid);
1658         if (t != NULL) {
1659                 if (t->hw.c_resolution)
1660                         gstatus.resolution = t->hw.c_resolution(t);
1661                 else
1662                         gstatus.resolution = t->hw.resolution;
1663                 if (t->hw.precise_resolution) {
1664                         t->hw.precise_resolution(t, &gstatus.resolution_num,
1665                                                  &gstatus.resolution_den);
1666                 } else {
1667                         gstatus.resolution_num = gstatus.resolution;
1668                         gstatus.resolution_den = 1000000000uL;
1669                 }
1670         } else {
1671                 err = -ENODEV;
1672         }
1673         mutex_unlock(&register_mutex);
1674         if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1675                 err = -EFAULT;
1676         return err;
1677 }
1678
1679 static int snd_timer_user_tselect(struct file *file,
1680                                   struct snd_timer_select __user *_tselect)
1681 {
1682         struct snd_timer_user *tu;
1683         struct snd_timer_select tselect;
1684         char str[32];
1685         int err = 0;
1686
1687         tu = file->private_data;
1688         if (tu->timeri) {
1689                 snd_timer_close(tu->timeri);
1690                 tu->timeri = NULL;
1691         }
1692         if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1693                 err = -EFAULT;
1694                 goto __err;
1695         }
1696         sprintf(str, "application %i", current->pid);
1697         if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1698                 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1699         err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1700         if (err < 0)
1701                 goto __err;
1702
1703         tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1704         tu->timeri->callback = tu->tread
1705                         ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1706         tu->timeri->ccallback = snd_timer_user_ccallback;
1707         tu->timeri->callback_data = (void *)tu;
1708         tu->timeri->disconnect = snd_timer_user_disconnect;
1709
1710       __err:
1711         return err;
1712 }
1713
1714 static int snd_timer_user_info(struct file *file,
1715                                struct snd_timer_info __user *_info)
1716 {
1717         struct snd_timer_user *tu;
1718         struct snd_timer_info *info;
1719         struct snd_timer *t;
1720         int err = 0;
1721
1722         tu = file->private_data;
1723         if (!tu->timeri)
1724                 return -EBADFD;
1725         t = tu->timeri->timer;
1726         if (!t)
1727                 return -EBADFD;
1728
1729         info = kzalloc(sizeof(*info), GFP_KERNEL);
1730         if (! info)
1731                 return -ENOMEM;
1732         info->card = t->card ? t->card->number : -1;
1733         if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1734                 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1735         strlcpy(info->id, t->id, sizeof(info->id));
1736         strlcpy(info->name, t->name, sizeof(info->name));
1737         info->resolution = t->hw.resolution;
1738         if (copy_to_user(_info, info, sizeof(*_info)))
1739                 err = -EFAULT;
1740         kfree(info);
1741         return err;
1742 }
1743
1744 static int snd_timer_user_params(struct file *file,
1745                                  struct snd_timer_params __user *_params)
1746 {
1747         struct snd_timer_user *tu;
1748         struct snd_timer_params params;
1749         struct snd_timer *t;
1750         int err;
1751
1752         tu = file->private_data;
1753         if (!tu->timeri)
1754                 return -EBADFD;
1755         t = tu->timeri->timer;
1756         if (!t)
1757                 return -EBADFD;
1758         if (copy_from_user(&params, _params, sizeof(params)))
1759                 return -EFAULT;
1760         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1761                 u64 resolution;
1762
1763                 if (params.ticks < 1) {
1764                         err = -EINVAL;
1765                         goto _end;
1766                 }
1767
1768                 /* Don't allow resolution less than 1ms */
1769                 resolution = snd_timer_resolution(tu->timeri);
1770                 resolution *= params.ticks;
1771                 if (resolution < 1000000) {
1772                         err = -EINVAL;
1773                         goto _end;
1774                 }
1775         }
1776         if (params.queue_size > 0 &&
1777             (params.queue_size < 32 || params.queue_size > 1024)) {
1778                 err = -EINVAL;
1779                 goto _end;
1780         }
1781         if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1782                               (1<<SNDRV_TIMER_EVENT_TICK)|
1783                               (1<<SNDRV_TIMER_EVENT_START)|
1784                               (1<<SNDRV_TIMER_EVENT_STOP)|
1785                               (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1786                               (1<<SNDRV_TIMER_EVENT_PAUSE)|
1787                               (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1788                               (1<<SNDRV_TIMER_EVENT_RESUME)|
1789                               (1<<SNDRV_TIMER_EVENT_MSTART)|
1790                               (1<<SNDRV_TIMER_EVENT_MSTOP)|
1791                               (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1792                               (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1793                               (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1794                               (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1795                 err = -EINVAL;
1796                 goto _end;
1797         }
1798         snd_timer_stop(tu->timeri);
1799         spin_lock_irq(&t->lock);
1800         tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1801                                SNDRV_TIMER_IFLG_EXCLUSIVE|
1802                                SNDRV_TIMER_IFLG_EARLY_EVENT);
1803         if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1804                 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1805         if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1806                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1807         if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1808                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1809         spin_unlock_irq(&t->lock);
1810         if (params.queue_size > 0 &&
1811             (unsigned int)tu->queue_size != params.queue_size) {
1812                 err = realloc_user_queue(tu, params.queue_size);
1813                 if (err < 0)
1814                         goto _end;
1815         }
1816         spin_lock_irq(&tu->qlock);
1817         tu->qhead = tu->qtail = tu->qused = 0;
1818         if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1819                 if (tu->tread) {
1820                         struct snd_timer_tread tread;
1821                         memset(&tread, 0, sizeof(tread));
1822                         tread.event = SNDRV_TIMER_EVENT_EARLY;
1823                         tread.tstamp.tv_sec = 0;
1824                         tread.tstamp.tv_nsec = 0;
1825                         tread.val = 0;
1826                         snd_timer_user_append_to_tqueue(tu, &tread);
1827                 } else {
1828                         struct snd_timer_read *r = &tu->queue[0];
1829                         r->resolution = 0;
1830                         r->ticks = 0;
1831                         tu->qused++;
1832                         tu->qtail++;
1833                 }
1834         }
1835         tu->filter = params.filter;
1836         tu->ticks = params.ticks;
1837         spin_unlock_irq(&tu->qlock);
1838         err = 0;
1839  _end:
1840         if (copy_to_user(_params, &params, sizeof(params)))
1841                 return -EFAULT;
1842         return err;
1843 }
1844
1845 static int snd_timer_user_status(struct file *file,
1846                                  struct snd_timer_status __user *_status)
1847 {
1848         struct snd_timer_user *tu;
1849         struct snd_timer_status status;
1850
1851         tu = file->private_data;
1852         if (!tu->timeri)
1853                 return -EBADFD;
1854         memset(&status, 0, sizeof(status));
1855         status.tstamp = tu->tstamp;
1856         status.resolution = snd_timer_resolution(tu->timeri);
1857         status.lost = tu->timeri->lost;
1858         status.overrun = tu->overrun;
1859         spin_lock_irq(&tu->qlock);
1860         status.queue = tu->qused;
1861         spin_unlock_irq(&tu->qlock);
1862         if (copy_to_user(_status, &status, sizeof(status)))
1863                 return -EFAULT;
1864         return 0;
1865 }
1866
1867 static int snd_timer_user_start(struct file *file)
1868 {
1869         int err;
1870         struct snd_timer_user *tu;
1871
1872         tu = file->private_data;
1873         if (!tu->timeri)
1874                 return -EBADFD;
1875         snd_timer_stop(tu->timeri);
1876         tu->timeri->lost = 0;
1877         tu->last_resolution = 0;
1878         return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1879 }
1880
1881 static int snd_timer_user_stop(struct file *file)
1882 {
1883         int err;
1884         struct snd_timer_user *tu;
1885
1886         tu = file->private_data;
1887         if (!tu->timeri)
1888                 return -EBADFD;
1889         return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1890 }
1891
1892 static int snd_timer_user_continue(struct file *file)
1893 {
1894         int err;
1895         struct snd_timer_user *tu;
1896
1897         tu = file->private_data;
1898         if (!tu->timeri)
1899                 return -EBADFD;
1900         /* start timer instead of continue if it's not used before */
1901         if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
1902                 return snd_timer_user_start(file);
1903         tu->timeri->lost = 0;
1904         return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1905 }
1906
1907 static int snd_timer_user_pause(struct file *file)
1908 {
1909         int err;
1910         struct snd_timer_user *tu;
1911
1912         tu = file->private_data;
1913         if (!tu->timeri)
1914                 return -EBADFD;
1915         return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1916 }
1917
1918 enum {
1919         SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1920         SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1921         SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1922         SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1923 };
1924
1925 static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1926                                  unsigned long arg)
1927 {
1928         struct snd_timer_user *tu;
1929         void __user *argp = (void __user *)arg;
1930         int __user *p = argp;
1931
1932         tu = file->private_data;
1933         switch (cmd) {
1934         case SNDRV_TIMER_IOCTL_PVERSION:
1935                 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1936         case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1937                 return snd_timer_user_next_device(argp);
1938         case SNDRV_TIMER_IOCTL_TREAD:
1939         {
1940                 int xarg, old_tread;
1941
1942                 if (tu->timeri) /* too late */
1943                         return -EBUSY;
1944                 if (get_user(xarg, p))
1945                         return -EFAULT;
1946                 old_tread = tu->tread;
1947                 tu->tread = xarg ? 1 : 0;
1948                 if (tu->tread != old_tread &&
1949                     realloc_user_queue(tu, tu->queue_size) < 0) {
1950                         tu->tread = old_tread;
1951                         return -ENOMEM;
1952                 }
1953                 return 0;
1954         }
1955         case SNDRV_TIMER_IOCTL_GINFO:
1956                 return snd_timer_user_ginfo(file, argp);
1957         case SNDRV_TIMER_IOCTL_GPARAMS:
1958                 return snd_timer_user_gparams(file, argp);
1959         case SNDRV_TIMER_IOCTL_GSTATUS:
1960                 return snd_timer_user_gstatus(file, argp);
1961         case SNDRV_TIMER_IOCTL_SELECT:
1962                 return snd_timer_user_tselect(file, argp);
1963         case SNDRV_TIMER_IOCTL_INFO:
1964                 return snd_timer_user_info(file, argp);
1965         case SNDRV_TIMER_IOCTL_PARAMS:
1966                 return snd_timer_user_params(file, argp);
1967         case SNDRV_TIMER_IOCTL_STATUS:
1968                 return snd_timer_user_status(file, argp);
1969         case SNDRV_TIMER_IOCTL_START:
1970         case SNDRV_TIMER_IOCTL_START_OLD:
1971                 return snd_timer_user_start(file);
1972         case SNDRV_TIMER_IOCTL_STOP:
1973         case SNDRV_TIMER_IOCTL_STOP_OLD:
1974                 return snd_timer_user_stop(file);
1975         case SNDRV_TIMER_IOCTL_CONTINUE:
1976         case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1977                 return snd_timer_user_continue(file);
1978         case SNDRV_TIMER_IOCTL_PAUSE:
1979         case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1980                 return snd_timer_user_pause(file);
1981         }
1982         return -ENOTTY;
1983 }
1984
1985 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1986                                  unsigned long arg)
1987 {
1988         struct snd_timer_user *tu = file->private_data;
1989         long ret;
1990
1991         mutex_lock(&tu->ioctl_lock);
1992         ret = __snd_timer_user_ioctl(file, cmd, arg);
1993         mutex_unlock(&tu->ioctl_lock);
1994         return ret;
1995 }
1996
1997 static int snd_timer_user_fasync(int fd, struct file * file, int on)
1998 {
1999         struct snd_timer_user *tu;
2000
2001         tu = file->private_data;
2002         return fasync_helper(fd, file, on, &tu->fasync);
2003 }
2004
2005 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2006                                    size_t count, loff_t *offset)
2007 {
2008         struct snd_timer_user *tu;
2009         long result = 0, unit;
2010         int qhead;
2011         int err = 0;
2012
2013         tu = file->private_data;
2014         unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
2015         mutex_lock(&tu->ioctl_lock);
2016         spin_lock_irq(&tu->qlock);
2017         while ((long)count - result >= unit) {
2018                 while (!tu->qused) {
2019                         wait_queue_entry_t wait;
2020
2021                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2022                                 err = -EAGAIN;
2023                                 goto _error;
2024                         }
2025
2026                         set_current_state(TASK_INTERRUPTIBLE);
2027                         init_waitqueue_entry(&wait, current);
2028                         add_wait_queue(&tu->qchange_sleep, &wait);
2029
2030                         spin_unlock_irq(&tu->qlock);
2031                         mutex_unlock(&tu->ioctl_lock);
2032                         schedule();
2033                         mutex_lock(&tu->ioctl_lock);
2034                         spin_lock_irq(&tu->qlock);
2035
2036                         remove_wait_queue(&tu->qchange_sleep, &wait);
2037
2038                         if (tu->disconnected) {
2039                                 err = -ENODEV;
2040                                 goto _error;
2041                         }
2042                         if (signal_pending(current)) {
2043                                 err = -ERESTARTSYS;
2044                                 goto _error;
2045                         }
2046                 }
2047
2048                 qhead = tu->qhead++;
2049                 tu->qhead %= tu->queue_size;
2050                 tu->qused--;
2051                 spin_unlock_irq(&tu->qlock);
2052
2053                 if (tu->tread) {
2054                         if (copy_to_user(buffer, &tu->tqueue[qhead],
2055                                          sizeof(struct snd_timer_tread)))
2056                                 err = -EFAULT;
2057                 } else {
2058                         if (copy_to_user(buffer, &tu->queue[qhead],
2059                                          sizeof(struct snd_timer_read)))
2060                                 err = -EFAULT;
2061                 }
2062
2063                 spin_lock_irq(&tu->qlock);
2064                 if (err < 0)
2065                         goto _error;
2066                 result += unit;
2067                 buffer += unit;
2068         }
2069  _error:
2070         spin_unlock_irq(&tu->qlock);
2071         mutex_unlock(&tu->ioctl_lock);
2072         return result > 0 ? result : err;
2073 }
2074
2075 static __poll_t snd_timer_user_poll(struct file *file, poll_table * wait)
2076 {
2077         __poll_t mask;
2078         struct snd_timer_user *tu;
2079
2080         tu = file->private_data;
2081
2082         poll_wait(file, &tu->qchange_sleep, wait);
2083
2084         mask = 0;
2085         spin_lock_irq(&tu->qlock);
2086         if (tu->qused)
2087                 mask |= EPOLLIN | EPOLLRDNORM;
2088         if (tu->disconnected)
2089                 mask |= EPOLLERR;
2090         spin_unlock_irq(&tu->qlock);
2091
2092         return mask;
2093 }
2094
2095 #ifdef CONFIG_COMPAT
2096 #include "timer_compat.c"
2097 #else
2098 #define snd_timer_user_ioctl_compat     NULL
2099 #endif
2100
2101 static const struct file_operations snd_timer_f_ops =
2102 {
2103         .owner =        THIS_MODULE,
2104         .read =         snd_timer_user_read,
2105         .open =         snd_timer_user_open,
2106         .release =      snd_timer_user_release,
2107         .llseek =       no_llseek,
2108         .poll =         snd_timer_user_poll,
2109         .unlocked_ioctl =       snd_timer_user_ioctl,
2110         .compat_ioctl = snd_timer_user_ioctl_compat,
2111         .fasync =       snd_timer_user_fasync,
2112 };
2113
2114 /* unregister the system timer */
2115 static void snd_timer_free_all(void)
2116 {
2117         struct snd_timer *timer, *n;
2118
2119         list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2120                 snd_timer_free(timer);
2121 }
2122
2123 static struct device timer_dev;
2124
2125 /*
2126  *  ENTRY functions
2127  */
2128
2129 static int __init alsa_timer_init(void)
2130 {
2131         int err;
2132
2133         snd_device_initialize(&timer_dev, NULL);
2134         dev_set_name(&timer_dev, "timer");
2135
2136 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2137         snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2138                               "system timer");
2139 #endif
2140
2141         err = snd_timer_register_system();
2142         if (err < 0) {
2143                 pr_err("ALSA: unable to register system timer (%i)\n", err);
2144                 goto put_timer;
2145         }
2146
2147         err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2148                                   &snd_timer_f_ops, NULL, &timer_dev);
2149         if (err < 0) {
2150                 pr_err("ALSA: unable to register timer device (%i)\n", err);
2151                 snd_timer_free_all();
2152                 goto put_timer;
2153         }
2154
2155         snd_timer_proc_init();
2156         return 0;
2157
2158 put_timer:
2159         put_device(&timer_dev);
2160         return err;
2161 }
2162
2163 static void __exit alsa_timer_exit(void)
2164 {
2165         snd_unregister_device(&timer_dev);
2166         snd_timer_free_all();
2167         put_device(&timer_dev);
2168         snd_timer_proc_done();
2169 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
2170         snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2171 #endif
2172 }
2173
2174 module_init(alsa_timer_init)
2175 module_exit(alsa_timer_exit)