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