sound/core/timer.c

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