git.oblomov.eu Git - linux-2.6/blob - sound/core/timer.c

   1 /*
   2  *  Timers abstract layer
   3  *  Copyright (c) by Jaroslav Kysela <perex@suse.cz>
   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 <sound/driver.h>
  23 #include <linux/delay.h>
  24 #include <linux/init.h>
  25 #include <linux/smp_lock.h>
  26 #include <linux/slab.h>
  27 #include <linux/time.h>
  28 #include <linux/mutex.h>
  29 #include <linux/moduleparam.h>
  30 #include <linux/string.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 #if defined(CONFIG_SND_HPET) || defined(CONFIG_SND_HPET_MODULE)
  40 #define DEFAULT_TIMER_LIMIT 3
  41 #elif defined(CONFIG_SND_RTCTIMER) || defined(CONFIG_SND_RTCTIMER_MODULE)
  42 #define DEFAULT_TIMER_LIMIT 2
  43 #else
  44 #define DEFAULT_TIMER_LIMIT 1
  45 #endif
  46
  47 static int timer_limit = DEFAULT_TIMER_LIMIT;
  48 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>, Takashi Iwai <tiwai@suse.de>");
  49 MODULE_DESCRIPTION("ALSA timer interface");
  50 MODULE_LICENSE("GPL");
  51 module_param(timer_limit, int, 0444);
  52 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
  53
  54 struct snd_timer_user {
  55         struct snd_timer_instance *timeri;
  56         int tread;              /* enhanced read with timestamps and events */
  57         unsigned long ticks;
  58         unsigned long overrun;
  59         int qhead;
  60         int qtail;
  61         int qused;
  62         int queue_size;
  63         struct snd_timer_read *queue;
  64         struct snd_timer_tread *tqueue;
  65         spinlock_t qlock;
  66         unsigned long last_resolution;
  67         unsigned int filter;
  68         struct timespec tstamp;         /* trigger tstamp */
  69         wait_queue_head_t qchange_sleep;
  70         struct fasync_struct *fasync;
  71         struct mutex tread_sem;
  72 };
  73
  74 /* list of timers */
  75 static LIST_HEAD(snd_timer_list);
  76
  77 /* list of slave instances */
  78 static LIST_HEAD(snd_timer_slave_list);
  79
  80 /* lock for slave active lists */
  81 static DEFINE_SPINLOCK(slave_active_lock);
  82
  83 static DEFINE_MUTEX(register_mutex);
  84
  85 static int snd_timer_free(struct snd_timer *timer);
  86 static int snd_timer_dev_free(struct snd_device *device);
  87 static int snd_timer_dev_register(struct snd_device *device);
  88 static int snd_timer_dev_disconnect(struct snd_device *device);
  89
  90 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
  91
  92 /*
  93  * create a timer instance with the given owner string.
  94  * when timer is not NULL, increments the module counter
  95  */
  96 static struct snd_timer_instance *snd_timer_instance_new(char *owner,
  97                                                          struct snd_timer *timer)
  98 {
  99         struct snd_timer_instance *timeri;
 100         timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
 101         if (timeri == NULL)
 102                 return NULL;
 103         timeri->owner = kstrdup(owner, GFP_KERNEL);
 104         if (! timeri->owner) {
 105                 kfree(timeri);
 106                 return NULL;
 107         }
 108         INIT_LIST_HEAD(&timeri->open_list);
 109         INIT_LIST_HEAD(&timeri->active_list);
 110         INIT_LIST_HEAD(&timeri->ack_list);
 111         INIT_LIST_HEAD(&timeri->slave_list_head);
 112         INIT_LIST_HEAD(&timeri->slave_active_head);
 113
 114         timeri->timer = timer;
 115         if (timer && !try_module_get(timer->module)) {
 116                 kfree(timeri->owner);
 117                 kfree(timeri);
 118                 return NULL;
 119         }
 120
 121         return timeri;
 122 }
 123
 124 /*
 125  * find a timer instance from the given timer id
 126  */
 127 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
 128 {
 129         struct snd_timer *timer = NULL;
 130
 131         list_for_each_entry(timer, &snd_timer_list, device_list) {
 132                 if (timer->tmr_class != tid->dev_class)
 133                         continue;
 134                 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
 135                      timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
 136                     (timer->card == NULL ||
 137                      timer->card->number != tid->card))
 138                         continue;
 139                 if (timer->tmr_device != tid->device)
 140                         continue;
 141                 if (timer->tmr_subdevice != tid->subdevice)
 142                         continue;
 143                 return timer;
 144         }
 145         return NULL;
 146 }
 147
 148 #ifdef CONFIG_KMOD
 149
 150 static void snd_timer_request(struct snd_timer_id *tid)
 151 {
 152         if (! current->fs->root)
 153                 return;
 154         switch (tid->dev_class) {
 155         case SNDRV_TIMER_CLASS_GLOBAL:
 156                 if (tid->device < timer_limit)
 157                         request_module("snd-timer-%i", tid->device);
 158                 break;
 159         case SNDRV_TIMER_CLASS_CARD:
 160         case SNDRV_TIMER_CLASS_PCM:
 161                 if (tid->card < snd_ecards_limit)
 162                         request_module("snd-card-%i", tid->card);
 163                 break;
 164         default:
 165                 break;
 166         }
 167 }
 168
 169 #endif
 170
 171 /*
 172  * look for a master instance matching with the slave id of the given slave.
 173  * when found, relink the open_link of the slave.
 174  *
 175  * call this with register_mutex down.
 176  */
 177 static void snd_timer_check_slave(struct snd_timer_instance *slave)
 178 {
 179         struct snd_timer *timer;
 180         struct snd_timer_instance *master;
 181
 182         /* FIXME: it's really dumb to look up all entries.. */
 183         list_for_each_entry(timer, &snd_timer_list, device_list) {
 184                 list_for_each_entry(master, &timer->open_list_head, open_list) {
 185                         if (slave->slave_class == master->slave_class &&
 186                             slave->slave_id == master->slave_id) {
 187                                 list_del(&slave->open_list);
 188                                 list_add_tail(&slave->open_list,
 189                                               &master->slave_list_head);
 190                                 spin_lock_irq(&slave_active_lock);
 191                                 slave->master = master;
 192                                 slave->timer = master->timer;
 193                                 spin_unlock_irq(&slave_active_lock);
 194                                 return;
 195                         }
 196                 }
 197         }
 198 }
 199
 200 /*
 201  * look for slave instances matching with the slave id of the given master.
 202  * when found, relink the open_link of slaves.
 203  *
 204  * call this with register_mutex down.
 205  */
 206 static void snd_timer_check_master(struct snd_timer_instance *master)
 207 {
 208         struct snd_timer_instance *slave, *tmp;
 209
 210         /* check all pending slaves */
 211         list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
 212                 if (slave->slave_class == master->slave_class &&
 213                     slave->slave_id == master->slave_id) {
 214                         list_move_tail(&slave->open_list, &master->slave_list_head);
 215                         spin_lock_irq(&slave_active_lock);
 216                         slave->master = master;
 217                         slave->timer = master->timer;
 218                         if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
 219                                 list_add_tail(&slave->active_list,
 220                                               &master->slave_active_head);
 221                         spin_unlock_irq(&slave_active_lock);
 222                 }
 223         }
 224 }
 225
 226 /*
 227  * open a timer instance
 228  * when opening a master, the slave id must be here given.
 229  */
 230 int snd_timer_open(struct snd_timer_instance **ti,
 231                    char *owner, struct snd_timer_id *tid,
 232                    unsigned int slave_id)
 233 {
 234         struct snd_timer *timer;
 235         struct snd_timer_instance *timeri = NULL;
 236
 237         if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
 238                 /* open a slave instance */
 239                 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
 240                     tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
 241                         snd_printd("invalid slave class %i\n", tid->dev_sclass);
 242                         return -EINVAL;
 243                 }
 244                 mutex_lock(&register_mutex);
 245                 timeri = snd_timer_instance_new(owner, NULL);
 246                 if (!timeri) {
 247                         mutex_unlock(&register_mutex);
 248                         return -ENOMEM;
 249                 }
 250                 timeri->slave_class = tid->dev_sclass;
 251                 timeri->slave_id = tid->device;
 252                 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
 253                 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
 254                 snd_timer_check_slave(timeri);
 255                 mutex_unlock(&register_mutex);
 256                 *ti = timeri;
 257                 return 0;
 258         }
 259
 260         /* open a master instance */
 261         mutex_lock(&register_mutex);
 262         timer = snd_timer_find(tid);
 263 #ifdef CONFIG_KMOD
 264         if (timer == NULL) {
 265                 mutex_unlock(&register_mutex);
 266                 snd_timer_request(tid);
 267                 mutex_lock(&register_mutex);
 268                 timer = snd_timer_find(tid);
 269         }
 270 #endif
 271         if (!timer) {
 272                 mutex_unlock(&register_mutex);
 273                 return -ENODEV;
 274         }
 275         if (!list_empty(&timer->open_list_head)) {
 276                 timeri = list_entry(timer->open_list_head.next,
 277                                     struct snd_timer_instance, open_list);
 278                 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
 279                         mutex_unlock(&register_mutex);
 280                         return -EBUSY;
 281                 }
 282         }
 283         timeri = snd_timer_instance_new(owner, timer);
 284         if (!timeri) {
 285                 mutex_unlock(&register_mutex);
 286                 return -ENOMEM;
 287         }
 288         timeri->slave_class = tid->dev_sclass;
 289         timeri->slave_id = slave_id;
 290         if (list_empty(&timer->open_list_head) && timer->hw.open)
 291                 timer->hw.open(timer);
 292         list_add_tail(&timeri->open_list, &timer->open_list_head);
 293         snd_timer_check_master(timeri);
 294         mutex_unlock(&register_mutex);
 295         *ti = timeri;
 296         return 0;
 297 }
 298
 299 static int _snd_timer_stop(struct snd_timer_instance *timeri,
 300                            int keep_flag, int event);
 301
 302 /*
 303  * close a timer instance
 304  */
 305 int snd_timer_close(struct snd_timer_instance *timeri)
 306 {
 307         struct snd_timer *timer = NULL;
 308         struct snd_timer_instance *slave, *tmp;
 309
 310         snd_assert(timeri != NULL, return -ENXIO);
 311
 312         /* force to stop the timer */
 313         snd_timer_stop(timeri);
 314
 315         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 316                 /* wait, until the active callback is finished */
 317                 spin_lock_irq(&slave_active_lock);
 318                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 319                         spin_unlock_irq(&slave_active_lock);
 320                         udelay(10);
 321                         spin_lock_irq(&slave_active_lock);
 322                 }
 323                 spin_unlock_irq(&slave_active_lock);
 324                 mutex_lock(&register_mutex);
 325                 list_del(&timeri->open_list);
 326                 mutex_unlock(&register_mutex);
 327         } else {
 328                 timer = timeri->timer;
 329                 /* wait, until the active callback is finished */
 330                 spin_lock_irq(&timer->lock);
 331                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 332                         spin_unlock_irq(&timer->lock);
 333                         udelay(10);
 334                         spin_lock_irq(&timer->lock);
 335                 }
 336                 spin_unlock_irq(&timer->lock);
 337                 mutex_lock(&register_mutex);
 338                 list_del(&timeri->open_list);
 339                 if (timer && list_empty(&timer->open_list_head) &&
 340                     timer->hw.close)
 341                         timer->hw.close(timer);
 342                 /* remove slave links */
 343                 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
 344                                          open_list) {
 345                         spin_lock_irq(&slave_active_lock);
 346                         _snd_timer_stop(slave, 1, SNDRV_TIMER_EVENT_RESOLUTION);
 347                         list_move_tail(&slave->open_list, &snd_timer_slave_list);
 348                         slave->master = NULL;
 349                         slave->timer = NULL;
 350                         spin_unlock_irq(&slave_active_lock);
 351                 }
 352                 mutex_unlock(&register_mutex);
 353         }
 354         if (timeri->private_free)
 355                 timeri->private_free(timeri);
 356         kfree(timeri->owner);
 357         kfree(timeri);
 358         if (timer)
 359                 module_put(timer->module);
 360         return 0;
 361 }
 362
 363 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
 364 {
 365         struct snd_timer * timer;
 366
 367         if (timeri == NULL)
 368                 return 0;
 369         if ((timer = timeri->timer) != NULL) {
 370                 if (timer->hw.c_resolution)
 371                         return timer->hw.c_resolution(timer);
 372                 return timer->hw.resolution;
 373         }
 374         return 0;
 375 }
 376
 377 static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
 378 {
 379         struct snd_timer *timer;
 380         unsigned long flags;
 381         unsigned long resolution = 0;
 382         struct snd_timer_instance *ts;
 383         struct timespec tstamp;
 384
 385         getnstimeofday(&tstamp);
 386         snd_assert(event >= SNDRV_TIMER_EVENT_START &&
 387                    event <= SNDRV_TIMER_EVENT_PAUSE, return);
 388         if (event == SNDRV_TIMER_EVENT_START ||
 389             event == SNDRV_TIMER_EVENT_CONTINUE)
 390                 resolution = snd_timer_resolution(ti);
 391         if (ti->ccallback)
 392                 ti->ccallback(ti, SNDRV_TIMER_EVENT_START, &tstamp, resolution);
 393         if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
 394                 return;
 395         timer = ti->timer;
 396         if (timer == NULL)
 397                 return;
 398         if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 399                 return;
 400         spin_lock_irqsave(&timer->lock, flags);
 401         list_for_each_entry(ts, &ti->slave_active_head, active_list)
 402                 if (ts->ccallback)
 403                         ts->ccallback(ti, event + 100, &tstamp, resolution);
 404         spin_unlock_irqrestore(&timer->lock, flags);
 405 }
 406
 407 static int snd_timer_start1(struct snd_timer *timer, struct snd_timer_instance *timeri,
 408                             unsigned long sticks)
 409 {
 410         list_del(&timeri->active_list);
 411         list_add_tail(&timeri->active_list, &timer->active_list_head);
 412         if (timer->running) {
 413                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 414                         goto __start_now;
 415                 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
 416                 timeri->flags |= SNDRV_TIMER_IFLG_START;
 417                 return 1;       /* delayed start */
 418         } else {
 419                 timer->sticks = sticks;
 420                 timer->hw.start(timer);
 421               __start_now:
 422                 timer->running++;
 423                 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 424                 return 0;
 425         }
 426 }
 427
 428 static int snd_timer_start_slave(struct snd_timer_instance *timeri)
 429 {
 430         unsigned long flags;
 431
 432         spin_lock_irqsave(&slave_active_lock, flags);
 433         timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 434         if (timeri->master)
 435                 list_add_tail(&timeri->active_list,
 436                               &timeri->master->slave_active_head);
 437         spin_unlock_irqrestore(&slave_active_lock, flags);
 438         return 1; /* delayed start */
 439 }
 440
 441 /*
 442  *  start the timer instance
 443  */
 444 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
 445 {
 446         struct snd_timer *timer;
 447         int result = -EINVAL;
 448         unsigned long flags;
 449
 450         if (timeri == NULL || ticks < 1)
 451                 return -EINVAL;
 452         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 453                 result = snd_timer_start_slave(timeri);
 454                 snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
 455                 return result;
 456         }
 457         timer = timeri->timer;
 458         if (timer == NULL)
 459                 return -EINVAL;
 460         spin_lock_irqsave(&timer->lock, flags);
 461         timeri->ticks = timeri->cticks = ticks;
 462         timeri->pticks = 0;
 463         result = snd_timer_start1(timer, timeri, ticks);
 464         spin_unlock_irqrestore(&timer->lock, flags);
 465         snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
 466         return result;
 467 }
 468
 469 static int _snd_timer_stop(struct snd_timer_instance * timeri,
 470                            int keep_flag, int event)
 471 {
 472         struct snd_timer *timer;
 473         unsigned long flags;
 474
 475         snd_assert(timeri != NULL, return -ENXIO);
 476
 477         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 478                 if (!keep_flag) {
 479                         spin_lock_irqsave(&slave_active_lock, flags);
 480                         timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 481                         spin_unlock_irqrestore(&slave_active_lock, flags);
 482                 }
 483                 goto __end;
 484         }
 485         timer = timeri->timer;
 486         if (!timer)
 487                 return -EINVAL;
 488         spin_lock_irqsave(&timer->lock, flags);
 489         list_del_init(&timeri->ack_list);
 490         list_del_init(&timeri->active_list);
 491         if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
 492             !(--timer->running)) {
 493                 timer->hw.stop(timer);
 494                 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
 495                         timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 496                         snd_timer_reschedule(timer, 0);
 497                         if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
 498                                 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 499                                 timer->hw.start(timer);
 500                         }
 501                 }
 502         }
 503         if (!keep_flag)
 504                 timeri->flags &=
 505                         ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
 506         spin_unlock_irqrestore(&timer->lock, flags);
 507       __end:
 508         if (event != SNDRV_TIMER_EVENT_RESOLUTION)
 509                 snd_timer_notify1(timeri, event);
 510         return 0;
 511 }
 512
 513 /*
 514  * stop the timer instance.
 515  *
 516  * do not call this from the timer callback!
 517  */
 518 int snd_timer_stop(struct snd_timer_instance *timeri)
 519 {
 520         struct snd_timer *timer;
 521         unsigned long flags;
 522         int err;
 523
 524         err = _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_STOP);
 525         if (err < 0)
 526                 return err;
 527         timer = timeri->timer;
 528         spin_lock_irqsave(&timer->lock, flags);
 529         timeri->cticks = timeri->ticks;
 530         timeri->pticks = 0;
 531         spin_unlock_irqrestore(&timer->lock, flags);
 532         return 0;
 533 }
 534
 535 /*
 536  * start again..  the tick is kept.
 537  */
 538 int snd_timer_continue(struct snd_timer_instance *timeri)
 539 {
 540         struct snd_timer *timer;
 541         int result = -EINVAL;
 542         unsigned long flags;
 543
 544         if (timeri == NULL)
 545                 return result;
 546         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 547                 return snd_timer_start_slave(timeri);
 548         timer = timeri->timer;
 549         if (! timer)
 550                 return -EINVAL;
 551         spin_lock_irqsave(&timer->lock, flags);
 552         if (!timeri->cticks)
 553                 timeri->cticks = 1;
 554         timeri->pticks = 0;
 555         result = snd_timer_start1(timer, timeri, timer->sticks);
 556         spin_unlock_irqrestore(&timer->lock, flags);
 557         snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_CONTINUE);
 558         return result;
 559 }
 560
 561 /*
 562  * pause.. remember the ticks left
 563  */
 564 int snd_timer_pause(struct snd_timer_instance * timeri)
 565 {
 566         return _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_PAUSE);
 567 }
 568
 569 /*
 570  * reschedule the timer
 571  *
 572  * start pending instances and check the scheduling ticks.
 573  * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
 574  */
 575 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
 576 {
 577         struct snd_timer_instance *ti;
 578         unsigned long ticks = ~0UL;
 579
 580         list_for_each_entry(ti, &timer->active_list_head, active_list) {
 581                 if (ti->flags & SNDRV_TIMER_IFLG_START) {
 582                         ti->flags &= ~SNDRV_TIMER_IFLG_START;
 583                         ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
 584                         timer->running++;
 585                 }
 586                 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
 587                         if (ticks > ti->cticks)
 588                                 ticks = ti->cticks;
 589                 }
 590         }
 591         if (ticks == ~0UL) {
 592                 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 593                 return;
 594         }
 595         if (ticks > timer->hw.ticks)
 596                 ticks = timer->hw.ticks;
 597         if (ticks_left != ticks)
 598                 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 599         timer->sticks = ticks;
 600 }
 601
 602 /*
 603  * timer tasklet
 604  *
 605  */
 606 static void snd_timer_tasklet(unsigned long arg)
 607 {
 608         struct snd_timer *timer = (struct snd_timer *) arg;
 609         struct snd_timer_instance *ti;
 610         struct list_head *p;
 611         unsigned long resolution, ticks;
 612         unsigned long flags;
 613
 614         spin_lock_irqsave(&timer->lock, flags);
 615         /* now process all callbacks */
 616         while (!list_empty(&timer->sack_list_head)) {
 617                 p = timer->sack_list_head.next;         /* get first item */
 618                 ti = list_entry(p, struct snd_timer_instance, ack_list);
 619
 620                 /* remove from ack_list and make empty */
 621                 list_del_init(p);
 622
 623                 ticks = ti->pticks;
 624                 ti->pticks = 0;
 625                 resolution = ti->resolution;
 626
 627                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 628                 spin_unlock(&timer->lock);
 629                 if (ti->callback)
 630                         ti->callback(ti, resolution, ticks);
 631                 spin_lock(&timer->lock);
 632                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 633         }
 634         spin_unlock_irqrestore(&timer->lock, flags);
 635 }
 636
 637 /*
 638  * timer interrupt
 639  *
 640  * ticks_left is usually equal to timer->sticks.
 641  *
 642  */
 643 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
 644 {
 645         struct snd_timer_instance *ti, *ts, *tmp;
 646         unsigned long resolution, ticks;
 647         struct list_head *p, *ack_list_head;
 648         unsigned long flags;
 649         int use_tasklet = 0;
 650
 651         if (timer == NULL)
 652                 return;
 653
 654         spin_lock_irqsave(&timer->lock, flags);
 655
 656         /* remember the current resolution */
 657         if (timer->hw.c_resolution)
 658                 resolution = timer->hw.c_resolution(timer);
 659         else
 660                 resolution = timer->hw.resolution;
 661
 662         /* loop for all active instances
 663          * Here we cannot use list_for_each_entry because the active_list of a
 664          * processed instance is relinked to done_list_head before the callback
 665          * is called.
 666          */
 667         list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
 668                                  active_list) {
 669                 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
 670                         continue;
 671                 ti->pticks += ticks_left;
 672                 ti->resolution = resolution;
 673                 if (ti->cticks < ticks_left)
 674                         ti->cticks = 0;
 675                 else
 676                         ti->cticks -= ticks_left;
 677                 if (ti->cticks) /* not expired */
 678                         continue;
 679                 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
 680                         ti->cticks = ti->ticks;
 681                 } else {
 682                         ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 683                         if (--timer->running)
 684                                 list_del(&ti->active_list);
 685                 }
 686                 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
 687                     (ti->flags & SNDRV_TIMER_IFLG_FAST))
 688                         ack_list_head = &timer->ack_list_head;
 689                 else
 690                         ack_list_head = &timer->sack_list_head;
 691                 if (list_empty(&ti->ack_list))
 692                         list_add_tail(&ti->ack_list, ack_list_head);
 693                 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
 694                         ts->pticks = ti->pticks;
 695                         ts->resolution = resolution;
 696                         if (list_empty(&ts->ack_list))
 697                                 list_add_tail(&ts->ack_list, ack_list_head);
 698                 }
 699         }
 700         if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
 701                 snd_timer_reschedule(timer, timer->sticks);
 702         if (timer->running) {
 703                 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
 704                         timer->hw.stop(timer);
 705                         timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 706                 }
 707                 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
 708                     (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
 709                         /* restart timer */
 710                         timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 711                         timer->hw.start(timer);
 712                 }
 713         } else {
 714                 timer->hw.stop(timer);
 715         }
 716
 717         /* now process all fast callbacks */
 718         while (!list_empty(&timer->ack_list_head)) {
 719                 p = timer->ack_list_head.next;          /* get first item */
 720                 ti = list_entry(p, struct snd_timer_instance, ack_list);
 721
 722                 /* remove from ack_list and make empty */
 723                 list_del_init(p);
 724
 725                 ticks = ti->pticks;
 726                 ti->pticks = 0;
 727
 728                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 729                 spin_unlock(&timer->lock);
 730                 if (ti->callback)
 731                         ti->callback(ti, resolution, ticks);
 732                 spin_lock(&timer->lock);
 733                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 734         }
 735
 736         /* do we have any slow callbacks? */
 737         use_tasklet = !list_empty(&timer->sack_list_head);
 738         spin_unlock_irqrestore(&timer->lock, flags);
 739
 740         if (use_tasklet)
 741                 tasklet_hi_schedule(&timer->task_queue);
 742 }
 743
 744 /*
 745
 746  */
 747
 748 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
 749                   struct snd_timer **rtimer)
 750 {
 751         struct snd_timer *timer;
 752         int err;
 753         static struct snd_device_ops ops = {
 754                 .dev_free = snd_timer_dev_free,
 755                 .dev_register = snd_timer_dev_register,
 756                 .dev_disconnect = snd_timer_dev_disconnect,
 757         };
 758
 759         snd_assert(tid != NULL, return -EINVAL);
 760         snd_assert(rtimer != NULL, return -EINVAL);
 761         *rtimer = NULL;
 762         timer = kzalloc(sizeof(*timer), GFP_KERNEL);
 763         if (timer == NULL) {
 764                 snd_printk(KERN_ERR "timer: cannot allocate\n");
 765                 return -ENOMEM;
 766         }
 767         timer->tmr_class = tid->dev_class;
 768         timer->card = card;
 769         timer->tmr_device = tid->device;
 770         timer->tmr_subdevice = tid->subdevice;
 771         if (id)
 772                 strlcpy(timer->id, id, sizeof(timer->id));
 773         INIT_LIST_HEAD(&timer->device_list);
 774         INIT_LIST_HEAD(&timer->open_list_head);
 775         INIT_LIST_HEAD(&timer->active_list_head);
 776         INIT_LIST_HEAD(&timer->ack_list_head);
 777         INIT_LIST_HEAD(&timer->sack_list_head);
 778         spin_lock_init(&timer->lock);
 779         tasklet_init(&timer->task_queue, snd_timer_tasklet,
 780                      (unsigned long)timer);
 781         if (card != NULL) {
 782                 timer->module = card->module;
 783                 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
 784                 if (err < 0) {
 785                         snd_timer_free(timer);
 786                         return err;
 787                 }
 788         }
 789         *rtimer = timer;
 790         return 0;
 791 }
 792
 793 static int snd_timer_free(struct snd_timer *timer)
 794 {
 795         snd_assert(timer != NULL, return -ENXIO);
 796
 797         mutex_lock(&register_mutex);
 798         if (! list_empty(&timer->open_list_head)) {
 799                 struct list_head *p, *n;
 800                 struct snd_timer_instance *ti;
 801                 snd_printk(KERN_WARNING "timer %p is busy?\n", timer);
 802                 list_for_each_safe(p, n, &timer->open_list_head) {
 803                         list_del_init(p);
 804                         ti = list_entry(p, struct snd_timer_instance, open_list);
 805                         ti->timer = NULL;
 806                 }
 807         }
 808         list_del(&timer->device_list);
 809         mutex_unlock(&register_mutex);
 810
 811         if (timer->private_free)
 812                 timer->private_free(timer);
 813         kfree(timer);
 814         return 0;
 815 }
 816
 817 static int snd_timer_dev_free(struct snd_device *device)
 818 {
 819         struct snd_timer *timer = device->device_data;
 820         return snd_timer_free(timer);
 821 }
 822
 823 static int snd_timer_dev_register(struct snd_device *dev)
 824 {
 825         struct snd_timer *timer = dev->device_data;
 826         struct snd_timer *timer1;
 827
 828         snd_assert(timer != NULL && timer->hw.start != NULL &&
 829                    timer->hw.stop != NULL, return -ENXIO);
 830         if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
 831             !timer->hw.resolution && timer->hw.c_resolution == NULL)
 832                 return -EINVAL;
 833
 834         mutex_lock(&register_mutex);
 835         list_for_each_entry(timer1, &snd_timer_list, device_list) {
 836                 if (timer1->tmr_class > timer->tmr_class)
 837                         break;
 838                 if (timer1->tmr_class < timer->tmr_class)
 839                         continue;
 840                 if (timer1->card && timer->card) {
 841                         if (timer1->card->number > timer->card->number)
 842                                 break;
 843                         if (timer1->card->number < timer->card->number)
 844                                 continue;
 845                 }
 846                 if (timer1->tmr_device > timer->tmr_device)
 847                         break;
 848                 if (timer1->tmr_device < timer->tmr_device)
 849                         continue;
 850                 if (timer1->tmr_subdevice > timer->tmr_subdevice)
 851                         break;
 852                 if (timer1->tmr_subdevice < timer->tmr_subdevice)
 853                         continue;
 854                 /* conflicts.. */
 855                 mutex_unlock(&register_mutex);
 856                 return -EBUSY;
 857         }
 858         list_add_tail(&timer->device_list, &timer1->device_list);
 859         mutex_unlock(&register_mutex);
 860         return 0;
 861 }
 862
 863 static int snd_timer_dev_disconnect(struct snd_device *device)
 864 {
 865         struct snd_timer *timer = device->device_data;
 866         mutex_lock(&register_mutex);
 867         list_del_init(&timer->device_list);
 868         mutex_unlock(&register_mutex);
 869         return 0;
 870 }
 871
 872 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
 873 {
 874         unsigned long flags;
 875         unsigned long resolution = 0;
 876         struct snd_timer_instance *ti, *ts;
 877
 878         if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
 879                 return;
 880         snd_assert(event >= SNDRV_TIMER_EVENT_MSTART &&
 881                    event <= SNDRV_TIMER_EVENT_MRESUME, return);
 882         spin_lock_irqsave(&timer->lock, flags);
 883         if (event == SNDRV_TIMER_EVENT_MSTART ||
 884             event == SNDRV_TIMER_EVENT_MCONTINUE ||
 885             event == SNDRV_TIMER_EVENT_MRESUME) {
 886                 if (timer->hw.c_resolution)
 887                         resolution = timer->hw.c_resolution(timer);
 888                 else
 889                         resolution = timer->hw.resolution;
 890         }
 891         list_for_each_entry(ti, &timer->active_list_head, active_list) {
 892                 if (ti->ccallback)
 893                         ti->ccallback(ti, event, tstamp, resolution);
 894                 list_for_each_entry(ts, &ti->slave_active_head, active_list)
 895                         if (ts->ccallback)
 896                                 ts->ccallback(ts, event, tstamp, resolution);
 897         }
 898         spin_unlock_irqrestore(&timer->lock, flags);
 899 }
 900
 901 /*
 902  * exported functions for global timers
 903  */
 904 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
 905 {
 906         struct snd_timer_id tid;
 907
 908         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
 909         tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
 910         tid.card = -1;
 911         tid.device = device;
 912         tid.subdevice = 0;
 913         return snd_timer_new(NULL, id, &tid, rtimer);
 914 }
 915
 916 int snd_timer_global_free(struct snd_timer *timer)
 917 {
 918         return snd_timer_free(timer);
 919 }
 920
 921 int snd_timer_global_register(struct snd_timer *timer)
 922 {
 923         struct snd_device dev;
 924
 925         memset(&dev, 0, sizeof(dev));
 926         dev.device_data = timer;
 927         return snd_timer_dev_register(&dev);
 928 }
 929
 930 /*
 931  *  System timer
 932  */
 933
 934 struct snd_timer_system_private {
 935         struct timer_list tlist;
 936         unsigned long last_expires;
 937         unsigned long last_jiffies;
 938         unsigned long correction;
 939 };
 940
 941 static void snd_timer_s_function(unsigned long data)
 942 {
 943         struct snd_timer *timer = (struct snd_timer *)data;
 944         struct snd_timer_system_private *priv = timer->private_data;
 945         unsigned long jiff = jiffies;
 946         if (time_after(jiff, priv->last_expires))
 947                 priv->correction += (long)jiff - (long)priv->last_expires;
 948         snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
 949 }
 950
 951 static int snd_timer_s_start(struct snd_timer * timer)
 952 {
 953         struct snd_timer_system_private *priv;
 954         unsigned long njiff;
 955
 956         priv = (struct snd_timer_system_private *) timer->private_data;
 957         njiff = (priv->last_jiffies = jiffies);
 958         if (priv->correction > timer->sticks - 1) {
 959                 priv->correction -= timer->sticks - 1;
 960                 njiff++;
 961         } else {
 962                 njiff += timer->sticks - priv->correction;
 963                 priv->correction = 0;
 964         }
 965         priv->last_expires = priv->tlist.expires = njiff;
 966         add_timer(&priv->tlist);
 967         return 0;
 968 }
 969
 970 static int snd_timer_s_stop(struct snd_timer * timer)
 971 {
 972         struct snd_timer_system_private *priv;
 973         unsigned long jiff;
 974
 975         priv = (struct snd_timer_system_private *) timer->private_data;
 976         del_timer(&priv->tlist);
 977         jiff = jiffies;
 978         if (time_before(jiff, priv->last_expires))
 979                 timer->sticks = priv->last_expires - jiff;
 980         else
 981                 timer->sticks = 1;
 982         priv->correction = 0;
 983         return 0;
 984 }
 985
 986 static struct snd_timer_hardware snd_timer_system =
 987 {
 988         .flags =        SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
 989         .resolution =   1000000000L / HZ,
 990         .ticks =        10000000L,
 991         .start =        snd_timer_s_start,
 992         .stop =         snd_timer_s_stop
 993 };
 994
 995 static void snd_timer_free_system(struct snd_timer *timer)
 996 {
 997         kfree(timer->private_data);
 998 }
 999
1000 static int snd_timer_register_system(void)
1001 {
1002         struct snd_timer *timer;
1003         struct snd_timer_system_private *priv;
1004         int err;
1005
1006         err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1007         if (err < 0)
1008                 return err;
1009         strcpy(timer->name, "system timer");
1010         timer->hw = snd_timer_system;
1011         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1012         if (priv == NULL) {
1013                 snd_timer_free(timer);
1014                 return -ENOMEM;
1015         }
1016         init_timer(&priv->tlist);
1017         priv->tlist.function = snd_timer_s_function;
1018         priv->tlist.data = (unsigned long) timer;
1019         timer->private_data = priv;
1020         timer->private_free = snd_timer_free_system;
1021         return snd_timer_global_register(timer);
1022 }
1023
1024 #ifdef CONFIG_PROC_FS
1025 /*
1026  *  Info interface
1027  */
1028
1029 static void snd_timer_proc_read(struct snd_info_entry *entry,
1030                                 struct snd_info_buffer *buffer)
1031 {
1032         struct snd_timer *timer;
1033         struct snd_timer_instance *ti;
1034
1035         mutex_lock(&register_mutex);
1036         list_for_each_entry(timer, &snd_timer_list, device_list) {
1037                 switch (timer->tmr_class) {
1038                 case SNDRV_TIMER_CLASS_GLOBAL:
1039                         snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1040                         break;
1041                 case SNDRV_TIMER_CLASS_CARD:
1042                         snd_iprintf(buffer, "C%i-%i: ",
1043                                     timer->card->number, timer->tmr_device);
1044                         break;
1045                 case SNDRV_TIMER_CLASS_PCM:
1046                         snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1047                                     timer->tmr_device, timer->tmr_subdevice);
1048                         break;
1049                 default:
1050                         snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1051                                     timer->card ? timer->card->number : -1,
1052                                     timer->tmr_device, timer->tmr_subdevice);
1053                 }
1054                 snd_iprintf(buffer, "%s :", timer->name);
1055                 if (timer->hw.resolution)
1056                         snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1057                                     timer->hw.resolution / 1000,
1058                                     timer->hw.resolution % 1000,
1059                                     timer->hw.ticks);
1060                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1061                         snd_iprintf(buffer, " SLAVE");
1062                 snd_iprintf(buffer, "\n");
1063                 list_for_each_entry(ti, &timer->open_list_head, open_list)
1064                         snd_iprintf(buffer, "  Client %s : %s\n",
1065                                     ti->owner ? ti->owner : "unknown",
1066                                     ti->flags & (SNDRV_TIMER_IFLG_START |
1067                                                  SNDRV_TIMER_IFLG_RUNNING)
1068                                     ? "running" : "stopped");
1069         }
1070         mutex_unlock(&register_mutex);
1071 }
1072
1073 static struct snd_info_entry *snd_timer_proc_entry;
1074
1075 static void __init snd_timer_proc_init(void)
1076 {
1077         struct snd_info_entry *entry;
1078
1079         entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1080         if (entry != NULL) {
1081                 entry->c.text.read = snd_timer_proc_read;
1082                 if (snd_info_register(entry) < 0) {
1083                         snd_info_free_entry(entry);
1084                         entry = NULL;
1085                 }
1086         }
1087         snd_timer_proc_entry = entry;
1088 }
1089
1090 static void __exit snd_timer_proc_done(void)
1091 {
1092         snd_info_free_entry(snd_timer_proc_entry);
1093 }
1094 #else /* !CONFIG_PROC_FS */
1095 #define snd_timer_proc_init()
1096 #define snd_timer_proc_done()
1097 #endif
1098
1099 /*
1100  *  USER SPACE interface
1101  */
1102
1103 static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1104                                      unsigned long resolution,
1105                                      unsigned long ticks)
1106 {
1107         struct snd_timer_user *tu = timeri->callback_data;
1108         struct snd_timer_read *r;
1109         int prev;
1110
1111         spin_lock(&tu->qlock);
1112         if (tu->qused > 0) {
1113                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1114                 r = &tu->queue[prev];
1115                 if (r->resolution == resolution) {
1116                         r->ticks += ticks;
1117                         goto __wake;
1118                 }
1119         }
1120         if (tu->qused >= tu->queue_size) {
1121                 tu->overrun++;
1122         } else {
1123                 r = &tu->queue[tu->qtail++];
1124                 tu->qtail %= tu->queue_size;
1125                 r->resolution = resolution;
1126                 r->ticks = ticks;
1127                 tu->qused++;
1128         }
1129       __wake:
1130         spin_unlock(&tu->qlock);
1131         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1132         wake_up(&tu->qchange_sleep);
1133 }
1134
1135 static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1136                                             struct snd_timer_tread *tread)
1137 {
1138         if (tu->qused >= tu->queue_size) {
1139                 tu->overrun++;
1140         } else {
1141                 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1142                 tu->qtail %= tu->queue_size;
1143                 tu->qused++;
1144         }
1145 }
1146
1147 static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1148                                      int event,
1149                                      struct timespec *tstamp,
1150                                      unsigned long resolution)
1151 {
1152         struct snd_timer_user *tu = timeri->callback_data;
1153         struct snd_timer_tread r1;
1154
1155         if (event >= SNDRV_TIMER_EVENT_START &&
1156             event <= SNDRV_TIMER_EVENT_PAUSE)
1157                 tu->tstamp = *tstamp;
1158         if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1159                 return;
1160         r1.event = event;
1161         r1.tstamp = *tstamp;
1162         r1.val = resolution;
1163         spin_lock(&tu->qlock);
1164         snd_timer_user_append_to_tqueue(tu, &r1);
1165         spin_unlock(&tu->qlock);
1166         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1167         wake_up(&tu->qchange_sleep);
1168 }
1169
1170 static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1171                                       unsigned long resolution,
1172                                       unsigned long ticks)
1173 {
1174         struct snd_timer_user *tu = timeri->callback_data;
1175         struct snd_timer_tread *r, r1;
1176         struct timespec tstamp;
1177         int prev, append = 0;
1178
1179         memset(&tstamp, 0, sizeof(tstamp));
1180         spin_lock(&tu->qlock);
1181         if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1182                            (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1183                 spin_unlock(&tu->qlock);
1184                 return;
1185         }
1186         if (tu->last_resolution != resolution || ticks > 0)
1187                 getnstimeofday(&tstamp);
1188         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1189             tu->last_resolution != resolution) {
1190                 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1191                 r1.tstamp = tstamp;
1192                 r1.val = resolution;
1193                 snd_timer_user_append_to_tqueue(tu, &r1);
1194                 tu->last_resolution = resolution;
1195                 append++;
1196         }
1197         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1198                 goto __wake;
1199         if (ticks == 0)
1200                 goto __wake;
1201         if (tu->qused > 0) {
1202                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1203                 r = &tu->tqueue[prev];
1204                 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1205                         r->tstamp = tstamp;
1206                         r->val += ticks;
1207                         append++;
1208                         goto __wake;
1209                 }
1210         }
1211         r1.event = SNDRV_TIMER_EVENT_TICK;
1212         r1.tstamp = tstamp;
1213         r1.val = ticks;
1214         snd_timer_user_append_to_tqueue(tu, &r1);
1215         append++;
1216       __wake:
1217         spin_unlock(&tu->qlock);
1218         if (append == 0)
1219                 return;
1220         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1221         wake_up(&tu->qchange_sleep);
1222 }
1223
1224 static int snd_timer_user_open(struct inode *inode, struct file *file)
1225 {
1226         struct snd_timer_user *tu;
1227
1228         tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1229         if (tu == NULL)
1230                 return -ENOMEM;
1231         spin_lock_init(&tu->qlock);
1232         init_waitqueue_head(&tu->qchange_sleep);
1233         mutex_init(&tu->tread_sem);
1234         tu->ticks = 1;
1235         tu->queue_size = 128;
1236         tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1237                             GFP_KERNEL);
1238         if (tu->queue == NULL) {
1239                 kfree(tu);
1240                 return -ENOMEM;
1241         }
1242         file->private_data = tu;
1243         return 0;
1244 }
1245
1246 static int snd_timer_user_release(struct inode *inode, struct file *file)
1247 {
1248         struct snd_timer_user *tu;
1249
1250         if (file->private_data) {
1251                 tu = file->private_data;
1252                 file->private_data = NULL;
1253                 fasync_helper(-1, file, 0, &tu->fasync);
1254                 if (tu->timeri)
1255                         snd_timer_close(tu->timeri);
1256                 kfree(tu->queue);
1257                 kfree(tu->tqueue);
1258                 kfree(tu);
1259         }
1260         return 0;
1261 }
1262
1263 static void snd_timer_user_zero_id(struct snd_timer_id *id)
1264 {
1265         id->dev_class = SNDRV_TIMER_CLASS_NONE;
1266         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1267         id->card = -1;
1268         id->device = -1;
1269         id->subdevice = -1;
1270 }
1271
1272 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1273 {
1274         id->dev_class = timer->tmr_class;
1275         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1276         id->card = timer->card ? timer->card->number : -1;
1277         id->device = timer->tmr_device;
1278         id->subdevice = timer->tmr_subdevice;
1279 }
1280
1281 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1282 {
1283         struct snd_timer_id id;
1284         struct snd_timer *timer;
1285         struct list_head *p;
1286
1287         if (copy_from_user(&id, _tid, sizeof(id)))
1288                 return -EFAULT;
1289         mutex_lock(&register_mutex);
1290         if (id.dev_class < 0) {         /* first item */
1291                 if (list_empty(&snd_timer_list))
1292                         snd_timer_user_zero_id(&id);
1293                 else {
1294                         timer = list_entry(snd_timer_list.next,
1295                                            struct snd_timer, device_list);
1296                         snd_timer_user_copy_id(&id, timer);
1297                 }
1298         } else {
1299                 switch (id.dev_class) {
1300                 case SNDRV_TIMER_CLASS_GLOBAL:
1301                         id.device = id.device < 0 ? 0 : id.device + 1;
1302                         list_for_each(p, &snd_timer_list) {
1303                                 timer = list_entry(p, struct snd_timer, device_list);
1304                                 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1305                                         snd_timer_user_copy_id(&id, timer);
1306                                         break;
1307                                 }
1308                                 if (timer->tmr_device >= id.device) {
1309                                         snd_timer_user_copy_id(&id, timer);
1310                                         break;
1311                                 }
1312                         }
1313                         if (p == &snd_timer_list)
1314                                 snd_timer_user_zero_id(&id);
1315                         break;
1316                 case SNDRV_TIMER_CLASS_CARD:
1317                 case SNDRV_TIMER_CLASS_PCM:
1318                         if (id.card < 0) {
1319                                 id.card = 0;
1320                         } else {
1321                                 if (id.card < 0) {
1322                                         id.card = 0;
1323                                 } else {
1324                                         if (id.device < 0) {
1325                                                 id.device = 0;
1326                                         } else {
1327                                                 if (id.subdevice < 0) {
1328                                                         id.subdevice = 0;
1329                                                 } else {
1330                                                         id.subdevice++;
1331                                                 }
1332                                         }
1333                                 }
1334                         }
1335                         list_for_each(p, &snd_timer_list) {
1336                                 timer = list_entry(p, struct snd_timer, device_list);
1337                                 if (timer->tmr_class > id.dev_class) {
1338                                         snd_timer_user_copy_id(&id, timer);
1339                                         break;
1340                                 }
1341                                 if (timer->tmr_class < id.dev_class)
1342                                         continue;
1343                                 if (timer->card->number > id.card) {
1344                                         snd_timer_user_copy_id(&id, timer);
1345                                         break;
1346                                 }
1347                                 if (timer->card->number < id.card)
1348                                         continue;
1349                                 if (timer->tmr_device > id.device) {
1350                                         snd_timer_user_copy_id(&id, timer);
1351                                         break;
1352                                 }
1353                                 if (timer->tmr_device < id.device)
1354                                         continue;
1355                                 if (timer->tmr_subdevice > id.subdevice) {
1356                                         snd_timer_user_copy_id(&id, timer);
1357                                         break;
1358                                 }
1359                                 if (timer->tmr_subdevice < id.subdevice)
1360                                         continue;
1361                                 snd_timer_user_copy_id(&id, timer);
1362                                 break;
1363                         }
1364                         if (p == &snd_timer_list)
1365                                 snd_timer_user_zero_id(&id);
1366                         break;
1367                 default:
1368                         snd_timer_user_zero_id(&id);
1369                 }
1370         }
1371         mutex_unlock(&register_mutex);
1372         if (copy_to_user(_tid, &id, sizeof(*_tid)))
1373                 return -EFAULT;
1374         return 0;
1375 }
1376
1377 static int snd_timer_user_ginfo(struct file *file,
1378                                 struct snd_timer_ginfo __user *_ginfo)
1379 {
1380         struct snd_timer_ginfo *ginfo;
1381         struct snd_timer_id tid;
1382         struct snd_timer *t;
1383         struct list_head *p;
1384         int err = 0;
1385
1386         ginfo = kmalloc(sizeof(*ginfo), GFP_KERNEL);
1387         if (! ginfo)
1388                 return -ENOMEM;
1389         if (copy_from_user(ginfo, _ginfo, sizeof(*ginfo))) {
1390                 kfree(ginfo);
1391                 return -EFAULT;
1392         }
1393         tid = ginfo->tid;
1394         memset(ginfo, 0, sizeof(*ginfo));
1395         ginfo->tid = tid;
1396         mutex_lock(&register_mutex);
1397         t = snd_timer_find(&tid);
1398         if (t != NULL) {
1399                 ginfo->card = t->card ? t->card->number : -1;
1400                 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1401                         ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1402                 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1403                 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1404                 ginfo->resolution = t->hw.resolution;
1405                 if (t->hw.resolution_min > 0) {
1406                         ginfo->resolution_min = t->hw.resolution_min;
1407                         ginfo->resolution_max = t->hw.resolution_max;
1408                 }
1409                 list_for_each(p, &t->open_list_head) {
1410                         ginfo->clients++;
1411                 }
1412         } else {
1413                 err = -ENODEV;
1414         }
1415         mutex_unlock(&register_mutex);
1416         if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1417                 err = -EFAULT;
1418         kfree(ginfo);
1419         return err;
1420 }
1421
1422 static int snd_timer_user_gparams(struct file *file,
1423                                   struct snd_timer_gparams __user *_gparams)
1424 {
1425         struct snd_timer_gparams gparams;
1426         struct snd_timer *t;
1427         int err;
1428
1429         if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1430                 return -EFAULT;
1431         mutex_lock(&register_mutex);
1432         t = snd_timer_find(&gparams.tid);
1433         if (!t) {
1434                 err = -ENODEV;
1435                 goto _error;
1436         }
1437         if (!list_empty(&t->open_list_head)) {
1438                 err = -EBUSY;
1439                 goto _error;
1440         }
1441         if (!t->hw.set_period) {
1442                 err = -ENOSYS;
1443                 goto _error;
1444         }
1445         err = t->hw.set_period(t, gparams.period_num, gparams.period_den);
1446 _error:
1447         mutex_unlock(&register_mutex);
1448         return err;
1449 }
1450
1451 static int snd_timer_user_gstatus(struct file *file,
1452                                   struct snd_timer_gstatus __user *_gstatus)
1453 {
1454         struct snd_timer_gstatus gstatus;
1455         struct snd_timer_id tid;
1456         struct snd_timer *t;
1457         int err = 0;
1458
1459         if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1460                 return -EFAULT;
1461         tid = gstatus.tid;
1462         memset(&gstatus, 0, sizeof(gstatus));
1463         gstatus.tid = tid;
1464         mutex_lock(&register_mutex);
1465         t = snd_timer_find(&tid);
1466         if (t != NULL) {
1467                 if (t->hw.c_resolution)
1468                         gstatus.resolution = t->hw.c_resolution(t);
1469                 else
1470                         gstatus.resolution = t->hw.resolution;
1471                 if (t->hw.precise_resolution) {
1472                         t->hw.precise_resolution(t, &gstatus.resolution_num,
1473                                                  &gstatus.resolution_den);
1474                 } else {
1475                         gstatus.resolution_num = gstatus.resolution;
1476                         gstatus.resolution_den = 1000000000uL;
1477                 }
1478         } else {
1479                 err = -ENODEV;
1480         }
1481         mutex_unlock(&register_mutex);
1482         if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1483                 err = -EFAULT;
1484         return err;
1485 }
1486
1487 static int snd_timer_user_tselect(struct file *file,
1488                                   struct snd_timer_select __user *_tselect)
1489 {
1490         struct snd_timer_user *tu;
1491         struct snd_timer_select tselect;
1492         char str[32];
1493         int err = 0;
1494
1495         tu = file->private_data;
1496         mutex_lock(&tu->tread_sem);
1497         if (tu->timeri) {
1498                 snd_timer_close(tu->timeri);
1499                 tu->timeri = NULL;
1500         }
1501         if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1502                 err = -EFAULT;
1503                 goto __err;
1504         }
1505         sprintf(str, "application %i", current->pid);
1506         if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1507                 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1508         err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1509         if (err < 0)
1510                 goto __err;
1511
1512         kfree(tu->queue);
1513         tu->queue = NULL;
1514         kfree(tu->tqueue);
1515         tu->tqueue = NULL;
1516         if (tu->tread) {
1517                 tu->tqueue = kmalloc(tu->queue_size * sizeof(struct snd_timer_tread),
1518                                      GFP_KERNEL);
1519                 if (tu->tqueue == NULL)
1520                         err = -ENOMEM;
1521         } else {
1522                 tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1523                                     GFP_KERNEL);
1524                 if (tu->queue == NULL)
1525                         err = -ENOMEM;
1526         }
1527
1528         if (err < 0) {
1529                 snd_timer_close(tu->timeri);
1530                 tu->timeri = NULL;
1531         } else {
1532                 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1533                 tu->timeri->callback = tu->tread
1534                         ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1535                 tu->timeri->ccallback = snd_timer_user_ccallback;
1536                 tu->timeri->callback_data = (void *)tu;
1537         }
1538
1539       __err:
1540         mutex_unlock(&tu->tread_sem);
1541         return err;
1542 }
1543
1544 static int snd_timer_user_info(struct file *file,
1545                                struct snd_timer_info __user *_info)
1546 {
1547         struct snd_timer_user *tu;
1548         struct snd_timer_info *info;
1549         struct snd_timer *t;
1550         int err = 0;
1551
1552         tu = file->private_data;
1553         snd_assert(tu->timeri != NULL, return -ENXIO);
1554         t = tu->timeri->timer;
1555         snd_assert(t != NULL, return -ENXIO);
1556
1557         info = kzalloc(sizeof(*info), GFP_KERNEL);
1558         if (! info)
1559                 return -ENOMEM;
1560         info->card = t->card ? t->card->number : -1;
1561         if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1562                 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1563         strlcpy(info->id, t->id, sizeof(info->id));
1564         strlcpy(info->name, t->name, sizeof(info->name));
1565         info->resolution = t->hw.resolution;
1566         if (copy_to_user(_info, info, sizeof(*_info)))
1567                 err = -EFAULT;
1568         kfree(info);
1569         return err;
1570 }
1571
1572 static int snd_timer_user_params(struct file *file,
1573                                  struct snd_timer_params __user *_params)
1574 {
1575         struct snd_timer_user *tu;
1576         struct snd_timer_params params;
1577         struct snd_timer *t;
1578         struct snd_timer_read *tr;
1579         struct snd_timer_tread *ttr;
1580         int err;
1581
1582         tu = file->private_data;
1583         snd_assert(tu->timeri != NULL, return -ENXIO);
1584         t = tu->timeri->timer;
1585         snd_assert(t != NULL, return -ENXIO);
1586         if (copy_from_user(&params, _params, sizeof(params)))
1587                 return -EFAULT;
1588         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE) && params.ticks < 1) {
1589                 err = -EINVAL;
1590                 goto _end;
1591         }
1592         if (params.queue_size > 0 &&
1593             (params.queue_size < 32 || params.queue_size > 1024)) {
1594                 err = -EINVAL;
1595                 goto _end;
1596         }
1597         if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1598                               (1<<SNDRV_TIMER_EVENT_TICK)|
1599                               (1<<SNDRV_TIMER_EVENT_START)|
1600                               (1<<SNDRV_TIMER_EVENT_STOP)|
1601                               (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1602                               (1<<SNDRV_TIMER_EVENT_PAUSE)|
1603                               (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1604                               (1<<SNDRV_TIMER_EVENT_RESUME)|
1605                               (1<<SNDRV_TIMER_EVENT_MSTART)|
1606                               (1<<SNDRV_TIMER_EVENT_MSTOP)|
1607                               (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1608                               (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1609                               (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1610                               (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1611                 err = -EINVAL;
1612                 goto _end;
1613         }
1614         snd_timer_stop(tu->timeri);
1615         spin_lock_irq(&t->lock);
1616         tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1617                                SNDRV_TIMER_IFLG_EXCLUSIVE|
1618                                SNDRV_TIMER_IFLG_EARLY_EVENT);
1619         if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1620                 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1621         if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1622                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1623         if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1624                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1625         spin_unlock_irq(&t->lock);
1626         if (params.queue_size > 0 &&
1627             (unsigned int)tu->queue_size != params.queue_size) {
1628                 if (tu->tread) {
1629                         ttr = kmalloc(params.queue_size * sizeof(*ttr),
1630                                       GFP_KERNEL);
1631                         if (ttr) {
1632                                 kfree(tu->tqueue);
1633                                 tu->queue_size = params.queue_size;
1634                                 tu->tqueue = ttr;
1635                         }
1636                 } else {
1637                         tr = kmalloc(params.queue_size * sizeof(*tr),
1638                                      GFP_KERNEL);
1639                         if (tr) {
1640                                 kfree(tu->queue);
1641                                 tu->queue_size = params.queue_size;
1642                                 tu->queue = tr;
1643                         }
1644                 }
1645         }
1646         tu->qhead = tu->qtail = tu->qused = 0;
1647         if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1648                 if (tu->tread) {
1649                         struct snd_timer_tread tread;
1650                         tread.event = SNDRV_TIMER_EVENT_EARLY;
1651                         tread.tstamp.tv_sec = 0;
1652                         tread.tstamp.tv_nsec = 0;
1653                         tread.val = 0;
1654                         snd_timer_user_append_to_tqueue(tu, &tread);
1655                 } else {
1656                         struct snd_timer_read *r = &tu->queue[0];
1657                         r->resolution = 0;
1658                         r->ticks = 0;
1659                         tu->qused++;
1660                         tu->qtail++;
1661                 }
1662         }
1663         tu->filter = params.filter;
1664         tu->ticks = params.ticks;
1665         err = 0;
1666  _end:
1667         if (copy_to_user(_params, &params, sizeof(params)))
1668                 return -EFAULT;
1669         return err;
1670 }
1671
1672 static int snd_timer_user_status(struct file *file,
1673                                  struct snd_timer_status __user *_status)
1674 {
1675         struct snd_timer_user *tu;
1676         struct snd_timer_status status;
1677
1678         tu = file->private_data;
1679         snd_assert(tu->timeri != NULL, return -ENXIO);
1680         memset(&status, 0, sizeof(status));
1681         status.tstamp = tu->tstamp;
1682         status.resolution = snd_timer_resolution(tu->timeri);
1683         status.lost = tu->timeri->lost;
1684         status.overrun = tu->overrun;
1685         spin_lock_irq(&tu->qlock);
1686         status.queue = tu->qused;
1687         spin_unlock_irq(&tu->qlock);
1688         if (copy_to_user(_status, &status, sizeof(status)))
1689                 return -EFAULT;
1690         return 0;
1691 }
1692
1693 static int snd_timer_user_start(struct file *file)
1694 {
1695         int err;
1696         struct snd_timer_user *tu;
1697
1698         tu = file->private_data;
1699         snd_assert(tu->timeri != NULL, return -ENXIO);
1700         snd_timer_stop(tu->timeri);
1701         tu->timeri->lost = 0;
1702         tu->last_resolution = 0;
1703         return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1704 }
1705
1706 static int snd_timer_user_stop(struct file *file)
1707 {
1708         int err;
1709         struct snd_timer_user *tu;
1710
1711         tu = file->private_data;
1712         snd_assert(tu->timeri != NULL, return -ENXIO);
1713         return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1714 }
1715
1716 static int snd_timer_user_continue(struct file *file)
1717 {
1718         int err;
1719         struct snd_timer_user *tu;
1720
1721         tu = file->private_data;
1722         snd_assert(tu->timeri != NULL, return -ENXIO);
1723         tu->timeri->lost = 0;
1724         return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1725 }
1726
1727 static int snd_timer_user_pause(struct file *file)
1728 {
1729         int err;
1730         struct snd_timer_user *tu;
1731
1732         tu = file->private_data;
1733         snd_assert(tu->timeri != NULL, return -ENXIO);
1734         return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1735 }
1736
1737 enum {
1738         SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1739         SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1740         SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1741         SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1742 };
1743
1744 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1745                                  unsigned long arg)
1746 {
1747         struct snd_timer_user *tu;
1748         void __user *argp = (void __user *)arg;
1749         int __user *p = argp;
1750
1751         tu = file->private_data;
1752         switch (cmd) {
1753         case SNDRV_TIMER_IOCTL_PVERSION:
1754                 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1755         case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1756                 return snd_timer_user_next_device(argp);
1757         case SNDRV_TIMER_IOCTL_TREAD:
1758         {
1759                 int xarg;
1760
1761                 mutex_lock(&tu->tread_sem);
1762                 if (tu->timeri) {       /* too late */
1763                         mutex_unlock(&tu->tread_sem);
1764                         return -EBUSY;
1765                 }
1766                 if (get_user(xarg, p)) {
1767                         mutex_unlock(&tu->tread_sem);
1768                         return -EFAULT;
1769                 }
1770                 tu->tread = xarg ? 1 : 0;
1771                 mutex_unlock(&tu->tread_sem);
1772                 return 0;
1773         }
1774         case SNDRV_TIMER_IOCTL_GINFO:
1775                 return snd_timer_user_ginfo(file, argp);
1776         case SNDRV_TIMER_IOCTL_GPARAMS:
1777                 return snd_timer_user_gparams(file, argp);
1778         case SNDRV_TIMER_IOCTL_GSTATUS:
1779                 return snd_timer_user_gstatus(file, argp);
1780         case SNDRV_TIMER_IOCTL_SELECT:
1781                 return snd_timer_user_tselect(file, argp);
1782         case SNDRV_TIMER_IOCTL_INFO:
1783                 return snd_timer_user_info(file, argp);
1784         case SNDRV_TIMER_IOCTL_PARAMS:
1785                 return snd_timer_user_params(file, argp);
1786         case SNDRV_TIMER_IOCTL_STATUS:
1787                 return snd_timer_user_status(file, argp);
1788         case SNDRV_TIMER_IOCTL_START:
1789         case SNDRV_TIMER_IOCTL_START_OLD:
1790                 return snd_timer_user_start(file);
1791         case SNDRV_TIMER_IOCTL_STOP:
1792         case SNDRV_TIMER_IOCTL_STOP_OLD:
1793                 return snd_timer_user_stop(file);
1794         case SNDRV_TIMER_IOCTL_CONTINUE:
1795         case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1796                 return snd_timer_user_continue(file);
1797         case SNDRV_TIMER_IOCTL_PAUSE:
1798         case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1799                 return snd_timer_user_pause(file);
1800         }
1801         return -ENOTTY;
1802 }
1803
1804 static int snd_timer_user_fasync(int fd, struct file * file, int on)
1805 {
1806         struct snd_timer_user *tu;
1807         int err;
1808
1809         tu = file->private_data;
1810         err = fasync_helper(fd, file, on, &tu->fasync);
1811         if (err < 0)
1812                 return err;
1813         return 0;
1814 }
1815
1816 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
1817                                    size_t count, loff_t *offset)
1818 {
1819         struct snd_timer_user *tu;
1820         long result = 0, unit;
1821         int err = 0;
1822
1823         tu = file->private_data;
1824         unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
1825         spin_lock_irq(&tu->qlock);
1826         while ((long)count - result >= unit) {
1827                 while (!tu->qused) {
1828                         wait_queue_t wait;
1829
1830                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1831                                 err = -EAGAIN;
1832                                 break;
1833                         }
1834
1835                         set_current_state(TASK_INTERRUPTIBLE);
1836                         init_waitqueue_entry(&wait, current);
1837                         add_wait_queue(&tu->qchange_sleep, &wait);
1838
1839                         spin_unlock_irq(&tu->qlock);
1840                         schedule();
1841                         spin_lock_irq(&tu->qlock);
1842
1843                         remove_wait_queue(&tu->qchange_sleep, &wait);
1844
1845                         if (signal_pending(current)) {
1846                                 err = -ERESTARTSYS;
1847                                 break;
1848                         }
1849                 }
1850
1851                 spin_unlock_irq(&tu->qlock);
1852                 if (err < 0)
1853                         goto _error;
1854
1855                 if (tu->tread) {
1856                         if (copy_to_user(buffer, &tu->tqueue[tu->qhead++],
1857                                          sizeof(struct snd_timer_tread))) {
1858                                 err = -EFAULT;
1859                                 goto _error;
1860                         }
1861                 } else {
1862                         if (copy_to_user(buffer, &tu->queue[tu->qhead++],
1863                                          sizeof(struct snd_timer_read))) {
1864                                 err = -EFAULT;
1865                                 goto _error;
1866                         }
1867                 }
1868
1869                 tu->qhead %= tu->queue_size;
1870
1871                 result += unit;
1872                 buffer += unit;
1873
1874                 spin_lock_irq(&tu->qlock);
1875                 tu->qused--;
1876         }
1877         spin_unlock_irq(&tu->qlock);
1878  _error:
1879         return result > 0 ? result : err;
1880 }
1881
1882 static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
1883 {
1884         unsigned int mask;
1885         struct snd_timer_user *tu;
1886
1887         tu = file->private_data;
1888
1889         poll_wait(file, &tu->qchange_sleep, wait);
1890
1891         mask = 0;
1892         if (tu->qused)
1893                 mask |= POLLIN | POLLRDNORM;
1894
1895         return mask;
1896 }
1897
1898 #ifdef CONFIG_COMPAT
1899 #include "timer_compat.c"
1900 #else
1901 #define snd_timer_user_ioctl_compat     NULL
1902 #endif
1903
1904 static const struct file_operations snd_timer_f_ops =
1905 {
1906         .owner =        THIS_MODULE,
1907         .read =         snd_timer_user_read,
1908         .open =         snd_timer_user_open,
1909         .release =      snd_timer_user_release,
1910         .poll =         snd_timer_user_poll,
1911         .unlocked_ioctl =       snd_timer_user_ioctl,
1912         .compat_ioctl = snd_timer_user_ioctl_compat,
1913         .fasync =       snd_timer_user_fasync,
1914 };
1915
1916 /*
1917  *  ENTRY functions
1918  */
1919
1920 static int __init alsa_timer_init(void)
1921 {
1922         int err;
1923
1924 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
1925         snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
1926                               "system timer");
1927 #endif
1928
1929         if ((err = snd_timer_register_system()) < 0)
1930                 snd_printk(KERN_ERR "unable to register system timer (%i)\n",
1931                            err);
1932         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
1933                                        &snd_timer_f_ops, NULL, "timer")) < 0)
1934                 snd_printk(KERN_ERR "unable to register timer device (%i)\n",
1935                            err);
1936         snd_timer_proc_init();
1937         return 0;
1938 }
1939
1940 static void __exit alsa_timer_exit(void)
1941 {
1942         struct list_head *p, *n;
1943
1944         snd_unregister_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0);
1945         /* unregister the system timer */
1946         list_for_each_safe(p, n, &snd_timer_list) {
1947                 struct snd_timer *timer = list_entry(p, struct snd_timer, device_list);
1948                 snd_timer_free(timer);
1949         }
1950         snd_timer_proc_done();
1951 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
1952         snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
1953 #endif
1954 }
1955
1956 module_init(alsa_timer_init)
1957 module_exit(alsa_timer_exit)
1958
1959 EXPORT_SYMBOL(snd_timer_open);
1960 EXPORT_SYMBOL(snd_timer_close);
1961 EXPORT_SYMBOL(snd_timer_resolution);
1962 EXPORT_SYMBOL(snd_timer_start);
1963 EXPORT_SYMBOL(snd_timer_stop);
1964 EXPORT_SYMBOL(snd_timer_continue);
1965 EXPORT_SYMBOL(snd_timer_pause);
1966 EXPORT_SYMBOL(snd_timer_new);
1967 EXPORT_SYMBOL(snd_timer_notify);
1968 EXPORT_SYMBOL(snd_timer_global_new);
1969 EXPORT_SYMBOL(snd_timer_global_free);
1970 EXPORT_SYMBOL(snd_timer_global_register);
1971 EXPORT_SYMBOL(snd_timer_interrupt);