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

   1 /*
   2  *  Timers abstract layer
   3  *  Copyright (c) by Jaroslav Kysela <perex@perex.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 <linux/delay.h>
  23 #include <linux/init.h>
  24 #include <linux/slab.h>
  25 #include <linux/time.h>
  26 #include <linux/mutex.h>
  27 #include <linux/moduleparam.h>
  28 #include <linux/string.h>
  29 #include <sound/core.h>
  30 #include <sound/timer.h>
  31 #include <sound/control.h>
  32 #include <sound/info.h>
  33 #include <sound/minors.h>
  34 #include <sound/initval.h>
  35 #include <linux/kmod.h>
  36
  37 #if defined(CONFIG_SND_HPET) || defined(CONFIG_SND_HPET_MODULE)
  38 #define DEFAULT_TIMER_LIMIT 3
  39 #elif defined(CONFIG_SND_RTCTIMER) || defined(CONFIG_SND_RTCTIMER_MODULE)
  40 #define DEFAULT_TIMER_LIMIT 2
  41 #else
  42 #define DEFAULT_TIMER_LIMIT 1
  43 #endif
  44
  45 static int timer_limit = DEFAULT_TIMER_LIMIT;
  46 static int timer_tstamp_monotonic = 1;
  47 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>");
  48 MODULE_DESCRIPTION("ALSA timer interface");
  49 MODULE_LICENSE("GPL");
  50 module_param(timer_limit, int, 0444);
  51 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
  52 module_param(timer_tstamp_monotonic, int, 0444);
  53 MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
  54
  55 struct snd_timer_user {
  56         struct snd_timer_instance *timeri;
  57         int tread;              /* enhanced read with timestamps and events */
  58         unsigned long ticks;
  59         unsigned long overrun;
  60         int qhead;
  61         int qtail;
  62         int qused;
  63         int queue_size;
  64         struct snd_timer_read *queue;
  65         struct snd_timer_tread *tqueue;
  66         spinlock_t qlock;
  67         unsigned long last_resolution;
  68         unsigned int filter;
  69         struct timespec tstamp;         /* trigger tstamp */
  70         wait_queue_head_t qchange_sleep;
  71         struct fasync_struct *fasync;
  72         struct mutex tread_sem;
  73 };
  74
  75 /* list of timers */
  76 static LIST_HEAD(snd_timer_list);
  77
  78 /* list of slave instances */
  79 static LIST_HEAD(snd_timer_slave_list);
  80
  81 /* lock for slave active lists */
  82 static DEFINE_SPINLOCK(slave_active_lock);
  83
  84 static DEFINE_MUTEX(register_mutex);
  85
  86 static int snd_timer_free(struct snd_timer *timer);
  87 static int snd_timer_dev_free(struct snd_device *device);
  88 static int snd_timer_dev_register(struct snd_device *device);
  89 static int snd_timer_dev_disconnect(struct snd_device *device);
  90
  91 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
  92
  93 /*
  94  * create a timer instance with the given owner string.
  95  * when timer is not NULL, increments the module counter
  96  */
  97 static struct snd_timer_instance *snd_timer_instance_new(char *owner,
  98                                                          struct snd_timer *timer)
  99 {
 100         struct snd_timer_instance *timeri;
 101         timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
 102         if (timeri == NULL)
 103                 return NULL;
 104         timeri->owner = kstrdup(owner, GFP_KERNEL);
 105         if (! timeri->owner) {
 106                 kfree(timeri);
 107                 return NULL;
 108         }
 109         INIT_LIST_HEAD(&timeri->open_list);
 110         INIT_LIST_HEAD(&timeri->active_list);
 111         INIT_LIST_HEAD(&timeri->ack_list);
 112         INIT_LIST_HEAD(&timeri->slave_list_head);
 113         INIT_LIST_HEAD(&timeri->slave_active_head);
 114
 115         timeri->timer = timer;
 116         if (timer && !try_module_get(timer->module)) {
 117                 kfree(timeri->owner);
 118                 kfree(timeri);
 119                 return NULL;
 120         }
 121
 122         return timeri;
 123 }
 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_KMOD
 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 /*
 171  * look for a master instance matching with the slave id of the given slave.
 172  * when found, relink the open_link of the slave.
 173  *
 174  * call this with register_mutex down.
 175  */
 176 static void snd_timer_check_slave(struct snd_timer_instance *slave)
 177 {
 178         struct snd_timer *timer;
 179         struct snd_timer_instance *master;
 180
 181         /* FIXME: it's really dumb to look up all entries.. */
 182         list_for_each_entry(timer, &snd_timer_list, device_list) {
 183                 list_for_each_entry(master, &timer->open_list_head, open_list) {
 184                         if (slave->slave_class == master->slave_class &&
 185                             slave->slave_id == master->slave_id) {
 186                                 list_del(&slave->open_list);
 187                                 list_add_tail(&slave->open_list,
 188                                               &master->slave_list_head);
 189                                 spin_lock_irq(&slave_active_lock);
 190                                 slave->master = master;
 191                                 slave->timer = master->timer;
 192                                 spin_unlock_irq(&slave_active_lock);
 193                                 return;
 194                         }
 195                 }
 196         }
 197 }
 198
 199 /*
 200  * look for slave instances matching with the slave id of the given master.
 201  * when found, relink the open_link of slaves.
 202  *
 203  * call this with register_mutex down.
 204  */
 205 static void snd_timer_check_master(struct snd_timer_instance *master)
 206 {
 207         struct snd_timer_instance *slave, *tmp;
 208
 209         /* check all pending slaves */
 210         list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
 211                 if (slave->slave_class == master->slave_class &&
 212                     slave->slave_id == master->slave_id) {
 213                         list_move_tail(&slave->open_list, &master->slave_list_head);
 214                         spin_lock_irq(&slave_active_lock);
 215                         slave->master = master;
 216                         slave->timer = master->timer;
 217                         if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
 218                                 list_add_tail(&slave->active_list,
 219                                               &master->slave_active_head);
 220                         spin_unlock_irq(&slave_active_lock);
 221                 }
 222         }
 223 }
 224
 225 /*
 226  * open a timer instance
 227  * when opening a master, the slave id must be here given.
 228  */
 229 int snd_timer_open(struct snd_timer_instance **ti,
 230                    char *owner, struct snd_timer_id *tid,
 231                    unsigned int slave_id)
 232 {
 233         struct snd_timer *timer;
 234         struct snd_timer_instance *timeri = NULL;
 235
 236         if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
 237                 /* open a slave instance */
 238                 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
 239                     tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
 240                         snd_printd("invalid slave class %i\n", tid->dev_sclass);
 241                         return -EINVAL;
 242                 }
 243                 mutex_lock(&register_mutex);
 244                 timeri = snd_timer_instance_new(owner, NULL);
 245                 if (!timeri) {
 246                         mutex_unlock(&register_mutex);
 247                         return -ENOMEM;
 248                 }
 249                 timeri->slave_class = tid->dev_sclass;
 250                 timeri->slave_id = tid->device;
 251                 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
 252                 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
 253                 snd_timer_check_slave(timeri);
 254                 mutex_unlock(&register_mutex);
 255                 *ti = timeri;
 256                 return 0;
 257         }
 258
 259         /* open a master instance */
 260         mutex_lock(&register_mutex);
 261         timer = snd_timer_find(tid);
 262 #ifdef CONFIG_KMOD
 263         if (timer == NULL) {
 264                 mutex_unlock(&register_mutex);
 265                 snd_timer_request(tid);
 266                 mutex_lock(&register_mutex);
 267                 timer = snd_timer_find(tid);
 268         }
 269 #endif
 270         if (!timer) {
 271                 mutex_unlock(&register_mutex);
 272                 return -ENODEV;
 273         }
 274         if (!list_empty(&timer->open_list_head)) {
 275                 timeri = list_entry(timer->open_list_head.next,
 276                                     struct snd_timer_instance, open_list);
 277                 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
 278                         mutex_unlock(&register_mutex);
 279                         return -EBUSY;
 280                 }
 281         }
 282         timeri = snd_timer_instance_new(owner, timer);
 283         if (!timeri) {
 284                 mutex_unlock(&register_mutex);
 285                 return -ENOMEM;
 286         }
 287         timeri->slave_class = tid->dev_sclass;
 288         timeri->slave_id = slave_id;
 289         if (list_empty(&timer->open_list_head) && timer->hw.open)
 290                 timer->hw.open(timer);
 291         list_add_tail(&timeri->open_list, &timer->open_list_head);
 292         snd_timer_check_master(timeri);
 293         mutex_unlock(&register_mutex);
 294         *ti = timeri;
 295         return 0;
 296 }
 297
 298 static int _snd_timer_stop(struct snd_timer_instance *timeri,
 299                            int keep_flag, int event);
 300
 301 /*
 302  * close a timer instance
 303  */
 304 int snd_timer_close(struct snd_timer_instance *timeri)
 305 {
 306         struct snd_timer *timer = NULL;
 307         struct snd_timer_instance *slave, *tmp;
 308
 309         snd_assert(timeri != NULL, return -ENXIO);
 310
 311         /* force to stop the timer */
 312         snd_timer_stop(timeri);
 313
 314         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 315                 /* wait, until the active callback is finished */
 316                 spin_lock_irq(&slave_active_lock);
 317                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 318                         spin_unlock_irq(&slave_active_lock);
 319                         udelay(10);
 320                         spin_lock_irq(&slave_active_lock);
 321                 }
 322                 spin_unlock_irq(&slave_active_lock);
 323                 mutex_lock(&register_mutex);
 324                 list_del(&timeri->open_list);
 325                 mutex_unlock(&register_mutex);
 326         } else {
 327                 timer = timeri->timer;
 328                 /* wait, until the active callback is finished */
 329                 spin_lock_irq(&timer->lock);
 330                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 331                         spin_unlock_irq(&timer->lock);
 332                         udelay(10);
 333                         spin_lock_irq(&timer->lock);
 334                 }
 335                 spin_unlock_irq(&timer->lock);
 336                 mutex_lock(&register_mutex);
 337                 list_del(&timeri->open_list);
 338                 if (timer && list_empty(&timer->open_list_head) &&
 339                     timer->hw.close)
 340                         timer->hw.close(timer);
 341                 /* remove slave links */
 342                 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
 343                                          open_list) {
 344                         spin_lock_irq(&slave_active_lock);
 345                         _snd_timer_stop(slave, 1, SNDRV_TIMER_EVENT_RESOLUTION);
 346                         list_move_tail(&slave->open_list, &snd_timer_slave_list);
 347                         slave->master = NULL;
 348                         slave->timer = NULL;
 349                         spin_unlock_irq(&slave_active_lock);
 350                 }
 351                 mutex_unlock(&register_mutex);
 352         }
 353         if (timeri->private_free)
 354                 timeri->private_free(timeri);
 355         kfree(timeri->owner);
 356         kfree(timeri);
 357         if (timer)
 358                 module_put(timer->module);
 359         return 0;
 360 }
 361
 362 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
 363 {
 364         struct snd_timer * timer;
 365
 366         if (timeri == NULL)
 367                 return 0;
 368         if ((timer = timeri->timer) != NULL) {
 369                 if (timer->hw.c_resolution)
 370                         return timer->hw.c_resolution(timer);
 371                 return timer->hw.resolution;
 372         }
 373         return 0;
 374 }
 375
 376 static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
 377 {
 378         struct snd_timer *timer;
 379         unsigned long flags;
 380         unsigned long resolution = 0;
 381         struct snd_timer_instance *ts;
 382         struct timespec tstamp;
 383
 384         if (timer_tstamp_monotonic)
 385                 do_posix_clock_monotonic_gettime(&tstamp);
 386         else
 387                 getnstimeofday(&tstamp);
 388         snd_assert(event >= SNDRV_TIMER_EVENT_START &&
 389                    event <= SNDRV_TIMER_EVENT_PAUSE, return);
 390         if (event == SNDRV_TIMER_EVENT_START ||
 391             event == SNDRV_TIMER_EVENT_CONTINUE)
 392                 resolution = snd_timer_resolution(ti);
 393         if (ti->ccallback)
 394                 ti->ccallback(ti, SNDRV_TIMER_EVENT_START, &tstamp, resolution);
 395         if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
 396                 return;
 397         timer = ti->timer;
 398         if (timer == NULL)
 399                 return;
 400         if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 401                 return;
 402         spin_lock_irqsave(&timer->lock, flags);
 403         list_for_each_entry(ts, &ti->slave_active_head, active_list)
 404                 if (ts->ccallback)
 405                         ts->ccallback(ti, event + 100, &tstamp, resolution);
 406         spin_unlock_irqrestore(&timer->lock, flags);
 407 }
 408
 409 static int snd_timer_start1(struct snd_timer *timer, struct snd_timer_instance *timeri,
 410                             unsigned long sticks)
 411 {
 412         list_del(&timeri->active_list);
 413         list_add_tail(&timeri->active_list, &timer->active_list_head);
 414         if (timer->running) {
 415                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 416                         goto __start_now;
 417                 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
 418                 timeri->flags |= SNDRV_TIMER_IFLG_START;
 419                 return 1;       /* delayed start */
 420         } else {
 421                 timer->sticks = sticks;
 422                 timer->hw.start(timer);
 423               __start_now:
 424                 timer->running++;
 425                 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 426                 return 0;
 427         }
 428 }
 429
 430 static int snd_timer_start_slave(struct snd_timer_instance *timeri)
 431 {
 432         unsigned long flags;
 433
 434         spin_lock_irqsave(&slave_active_lock, flags);
 435         timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 436         if (timeri->master)
 437                 list_add_tail(&timeri->active_list,
 438                               &timeri->master->slave_active_head);
 439         spin_unlock_irqrestore(&slave_active_lock, flags);
 440         return 1; /* delayed start */
 441 }
 442
 443 /*
 444  *  start the timer instance
 445  */
 446 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
 447 {
 448         struct snd_timer *timer;
 449         int result = -EINVAL;
 450         unsigned long flags;
 451
 452         if (timeri == NULL || ticks < 1)
 453                 return -EINVAL;
 454         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 455                 result = snd_timer_start_slave(timeri);
 456                 snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
 457                 return result;
 458         }
 459         timer = timeri->timer;
 460         if (timer == NULL)
 461                 return -EINVAL;
 462         spin_lock_irqsave(&timer->lock, flags);
 463         timeri->ticks = timeri->cticks = ticks;
 464         timeri->pticks = 0;
 465         result = snd_timer_start1(timer, timeri, ticks);
 466         spin_unlock_irqrestore(&timer->lock, flags);
 467         snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
 468         return result;
 469 }
 470
 471 static int _snd_timer_stop(struct snd_timer_instance * timeri,
 472                            int keep_flag, int event)
 473 {
 474         struct snd_timer *timer;
 475         unsigned long flags;
 476
 477         snd_assert(timeri != NULL, return -ENXIO);
 478
 479         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 480                 if (!keep_flag) {
 481                         spin_lock_irqsave(&slave_active_lock, flags);
 482                         timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 483                         spin_unlock_irqrestore(&slave_active_lock, flags);
 484                 }
 485                 goto __end;
 486         }
 487         timer = timeri->timer;
 488         if (!timer)
 489                 return -EINVAL;
 490         spin_lock_irqsave(&timer->lock, flags);
 491         list_del_init(&timeri->ack_list);
 492         list_del_init(&timeri->active_list);
 493         if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
 494             !(--timer->running)) {
 495                 timer->hw.stop(timer);
 496                 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
 497                         timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 498                         snd_timer_reschedule(timer, 0);
 499                         if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
 500                                 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 501                                 timer->hw.start(timer);
 502                         }
 503                 }
 504         }
 505         if (!keep_flag)
 506                 timeri->flags &=
 507                         ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
 508         spin_unlock_irqrestore(&timer->lock, flags);
 509       __end:
 510         if (event != SNDRV_TIMER_EVENT_RESOLUTION)
 511                 snd_timer_notify1(timeri, event);
 512         return 0;
 513 }
 514
 515 /*
 516  * stop the timer instance.
 517  *
 518  * do not call this from the timer callback!
 519  */
 520 int snd_timer_stop(struct snd_timer_instance *timeri)
 521 {
 522         struct snd_timer *timer;
 523         unsigned long flags;
 524         int err;
 525
 526         err = _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_STOP);
 527         if (err < 0)
 528                 return err;
 529         timer = timeri->timer;
 530         spin_lock_irqsave(&timer->lock, flags);
 531         timeri->cticks = timeri->ticks;
 532         timeri->pticks = 0;
 533         spin_unlock_irqrestore(&timer->lock, flags);
 534         return 0;
 535 }
 536
 537 /*
 538  * start again..  the tick is kept.
 539  */
 540 int snd_timer_continue(struct snd_timer_instance *timeri)
 541 {
 542         struct snd_timer *timer;
 543         int result = -EINVAL;
 544         unsigned long flags;
 545
 546         if (timeri == NULL)
 547                 return result;
 548         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 549                 return snd_timer_start_slave(timeri);
 550         timer = timeri->timer;
 551         if (! timer)
 552                 return -EINVAL;
 553         spin_lock_irqsave(&timer->lock, flags);
 554         if (!timeri->cticks)
 555                 timeri->cticks = 1;
 556         timeri->pticks = 0;
 557         result = snd_timer_start1(timer, timeri, timer->sticks);
 558         spin_unlock_irqrestore(&timer->lock, flags);
 559         snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_CONTINUE);
 560         return result;
 561 }
 562
 563 /*
 564  * pause.. remember the ticks left
 565  */
 566 int snd_timer_pause(struct snd_timer_instance * timeri)
 567 {
 568         return _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_PAUSE);
 569 }
 570
 571 /*
 572  * reschedule the timer
 573  *
 574  * start pending instances and check the scheduling ticks.
 575  * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
 576  */
 577 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
 578 {
 579         struct snd_timer_instance *ti;
 580         unsigned long ticks = ~0UL;
 581
 582         list_for_each_entry(ti, &timer->active_list_head, active_list) {
 583                 if (ti->flags & SNDRV_TIMER_IFLG_START) {
 584                         ti->flags &= ~SNDRV_TIMER_IFLG_START;
 585                         ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
 586                         timer->running++;
 587                 }
 588                 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
 589                         if (ticks > ti->cticks)
 590                                 ticks = ti->cticks;
 591                 }
 592         }
 593         if (ticks == ~0UL) {
 594                 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 595                 return;
 596         }
 597         if (ticks > timer->hw.ticks)
 598                 ticks = timer->hw.ticks;
 599         if (ticks_left != ticks)
 600                 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 601         timer->sticks = ticks;
 602 }
 603
 604 /*
 605  * timer tasklet
 606  *
 607  */
 608 static void snd_timer_tasklet(unsigned long arg)
 609 {
 610         struct snd_timer *timer = (struct snd_timer *) arg;
 611         struct snd_timer_instance *ti;
 612         struct list_head *p;
 613         unsigned long resolution, ticks;
 614         unsigned long flags;
 615
 616         spin_lock_irqsave(&timer->lock, flags);
 617         /* now process all callbacks */
 618         while (!list_empty(&timer->sack_list_head)) {
 619                 p = timer->sack_list_head.next;         /* get first item */
 620                 ti = list_entry(p, struct snd_timer_instance, ack_list);
 621
 622                 /* remove from ack_list and make empty */
 623                 list_del_init(p);
 624
 625                 ticks = ti->pticks;
 626                 ti->pticks = 0;
 627                 resolution = ti->resolution;
 628
 629                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 630                 spin_unlock(&timer->lock);
 631                 if (ti->callback)
 632                         ti->callback(ti, resolution, ticks);
 633                 spin_lock(&timer->lock);
 634                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 635         }
 636         spin_unlock_irqrestore(&timer->lock, flags);
 637 }
 638
 639 /*
 640  * timer interrupt
 641  *
 642  * ticks_left is usually equal to timer->sticks.
 643  *
 644  */
 645 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
 646 {
 647         struct snd_timer_instance *ti, *ts, *tmp;
 648         unsigned long resolution, ticks;
 649         struct list_head *p, *ack_list_head;
 650         unsigned long flags;
 651         int use_tasklet = 0;
 652
 653         if (timer == NULL)
 654                 return;
 655
 656         spin_lock_irqsave(&timer->lock, flags);
 657
 658         /* remember the current resolution */
 659         if (timer->hw.c_resolution)
 660                 resolution = timer->hw.c_resolution(timer);
 661         else
 662                 resolution = timer->hw.resolution;
 663
 664         /* loop for all active instances
 665          * Here we cannot use list_for_each_entry because the active_list of a
 666          * processed instance is relinked to done_list_head before the callback
 667          * is called.
 668          */
 669         list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
 670                                  active_list) {
 671                 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
 672                         continue;
 673                 ti->pticks += ticks_left;
 674                 ti->resolution = resolution;
 675                 if (ti->cticks < ticks_left)
 676                         ti->cticks = 0;
 677                 else
 678                         ti->cticks -= ticks_left;
 679                 if (ti->cticks) /* not expired */
 680                         continue;
 681                 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
 682                         ti->cticks = ti->ticks;
 683                 } else {
 684                         ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 685                         if (--timer->running)
 686                                 list_del(&ti->active_list);
 687                 }
 688                 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
 689                     (ti->flags & SNDRV_TIMER_IFLG_FAST))
 690                         ack_list_head = &timer->ack_list_head;
 691                 else
 692                         ack_list_head = &timer->sack_list_head;
 693                 if (list_empty(&ti->ack_list))
 694                         list_add_tail(&ti->ack_list, ack_list_head);
 695                 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
 696                         ts->pticks = ti->pticks;
 697                         ts->resolution = resolution;
 698                         if (list_empty(&ts->ack_list))
 699                                 list_add_tail(&ts->ack_list, ack_list_head);
 700                 }
 701         }
 702         if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
 703                 snd_timer_reschedule(timer, timer->sticks);
 704         if (timer->running) {
 705                 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
 706                         timer->hw.stop(timer);
 707                         timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 708                 }
 709                 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
 710                     (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
 711                         /* restart timer */
 712                         timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 713                         timer->hw.start(timer);
 714                 }
 715         } else {
 716                 timer->hw.stop(timer);
 717         }
 718
 719         /* now process all fast callbacks */
 720         while (!list_empty(&timer->ack_list_head)) {
 721                 p = timer->ack_list_head.next;          /* get first item */
 722                 ti = list_entry(p, struct snd_timer_instance, ack_list);
 723
 724                 /* remove from ack_list and make empty */
 725                 list_del_init(p);
 726
 727                 ticks = ti->pticks;
 728                 ti->pticks = 0;
 729
 730                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 731                 spin_unlock(&timer->lock);
 732                 if (ti->callback)
 733                         ti->callback(ti, resolution, ticks);
 734                 spin_lock(&timer->lock);
 735                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 736         }
 737
 738         /* do we have any slow callbacks? */
 739         use_tasklet = !list_empty(&timer->sack_list_head);
 740         spin_unlock_irqrestore(&timer->lock, flags);
 741
 742         if (use_tasklet)
 743                 tasklet_hi_schedule(&timer->task_queue);
 744 }
 745
 746 /*
 747
 748  */
 749
 750 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
 751                   struct snd_timer **rtimer)
 752 {
 753         struct snd_timer *timer;
 754         int err;
 755         static struct snd_device_ops ops = {
 756                 .dev_free = snd_timer_dev_free,
 757                 .dev_register = snd_timer_dev_register,
 758                 .dev_disconnect = snd_timer_dev_disconnect,
 759         };
 760
 761         snd_assert(tid != NULL, return -EINVAL);
 762         snd_assert(rtimer != NULL, return -EINVAL);
 763         *rtimer = NULL;
 764         timer = kzalloc(sizeof(*timer), GFP_KERNEL);
 765         if (timer == NULL) {
 766                 snd_printk(KERN_ERR "timer: cannot allocate\n");
 767                 return -ENOMEM;
 768         }
 769         timer->tmr_class = tid->dev_class;
 770         timer->card = card;
 771         timer->tmr_device = tid->device;
 772         timer->tmr_subdevice = tid->subdevice;
 773         if (id)
 774                 strlcpy(timer->id, id, sizeof(timer->id));
 775         INIT_LIST_HEAD(&timer->device_list);
 776         INIT_LIST_HEAD(&timer->open_list_head);
 777         INIT_LIST_HEAD(&timer->active_list_head);
 778         INIT_LIST_HEAD(&timer->ack_list_head);
 779         INIT_LIST_HEAD(&timer->sack_list_head);
 780         spin_lock_init(&timer->lock);
 781         tasklet_init(&timer->task_queue, snd_timer_tasklet,
 782                      (unsigned long)timer);
 783         if (card != NULL) {
 784                 timer->module = card->module;
 785                 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
 786                 if (err < 0) {
 787                         snd_timer_free(timer);
 788                         return err;
 789                 }
 790         }
 791         *rtimer = timer;
 792         return 0;
 793 }
 794
 795 static int snd_timer_free(struct snd_timer *timer)
 796 {
 797         snd_assert(timer != NULL, return -ENXIO);
 798
 799         mutex_lock(&register_mutex);
 800         if (! list_empty(&timer->open_list_head)) {
 801                 struct list_head *p, *n;
 802                 struct snd_timer_instance *ti;
 803                 snd_printk(KERN_WARNING "timer %p is busy?\n", timer);
 804                 list_for_each_safe(p, n, &timer->open_list_head) {
 805                         list_del_init(p);
 806                         ti = list_entry(p, struct snd_timer_instance, open_list);
 807                         ti->timer = NULL;
 808                 }
 809         }
 810         list_del(&timer->device_list);
 811         mutex_unlock(&register_mutex);
 812
 813         if (timer->private_free)
 814                 timer->private_free(timer);
 815         kfree(timer);
 816         return 0;
 817 }
 818
 819 static int snd_timer_dev_free(struct snd_device *device)
 820 {
 821         struct snd_timer *timer = device->device_data;
 822         return snd_timer_free(timer);
 823 }
 824
 825 static int snd_timer_dev_register(struct snd_device *dev)
 826 {
 827         struct snd_timer *timer = dev->device_data;
 828         struct snd_timer *timer1;
 829
 830         snd_assert(timer != NULL && timer->hw.start != NULL &&
 831                    timer->hw.stop != NULL, return -ENXIO);
 832         if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
 833             !timer->hw.resolution && timer->hw.c_resolution == NULL)
 834                 return -EINVAL;
 835
 836         mutex_lock(&register_mutex);
 837         list_for_each_entry(timer1, &snd_timer_list, device_list) {
 838                 if (timer1->tmr_class > timer->tmr_class)
 839                         break;
 840                 if (timer1->tmr_class < timer->tmr_class)
 841                         continue;
 842                 if (timer1->card && timer->card) {
 843                         if (timer1->card->number > timer->card->number)
 844                                 break;
 845                         if (timer1->card->number < timer->card->number)
 846                                 continue;
 847                 }
 848                 if (timer1->tmr_device > timer->tmr_device)
 849                         break;
 850                 if (timer1->tmr_device < timer->tmr_device)
 851                         continue;
 852                 if (timer1->tmr_subdevice > timer->tmr_subdevice)
 853                         break;
 854                 if (timer1->tmr_subdevice < timer->tmr_subdevice)
 855                         continue;
 856                 /* conflicts.. */
 857                 mutex_unlock(&register_mutex);
 858                 return -EBUSY;
 859         }
 860         list_add_tail(&timer->device_list, &timer1->device_list);
 861         mutex_unlock(&register_mutex);
 862         return 0;
 863 }
 864
 865 static int snd_timer_dev_disconnect(struct snd_device *device)
 866 {
 867         struct snd_timer *timer = device->device_data;
 868         mutex_lock(&register_mutex);
 869         list_del_init(&timer->device_list);
 870         mutex_unlock(&register_mutex);
 871         return 0;
 872 }
 873
 874 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
 875 {
 876         unsigned long flags;
 877         unsigned long resolution = 0;
 878         struct snd_timer_instance *ti, *ts;
 879
 880         if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
 881                 return;
 882         snd_assert(event >= SNDRV_TIMER_EVENT_MSTART &&
 883                    event <= SNDRV_TIMER_EVENT_MRESUME, return);
 884         spin_lock_irqsave(&timer->lock, flags);
 885         if (event == SNDRV_TIMER_EVENT_MSTART ||
 886             event == SNDRV_TIMER_EVENT_MCONTINUE ||
 887             event == SNDRV_TIMER_EVENT_MRESUME) {
 888                 if (timer->hw.c_resolution)
 889                         resolution = timer->hw.c_resolution(timer);
 890                 else
 891                         resolution = timer->hw.resolution;
 892         }
 893         list_for_each_entry(ti, &timer->active_list_head, active_list) {
 894                 if (ti->ccallback)
 895                         ti->ccallback(ti, event, tstamp, resolution);
 896                 list_for_each_entry(ts, &ti->slave_active_head, active_list)
 897                         if (ts->ccallback)
 898                                 ts->ccallback(ts, event, tstamp, resolution);
 899         }
 900         spin_unlock_irqrestore(&timer->lock, flags);
 901 }
 902
 903 /*
 904  * exported functions for global timers
 905  */
 906 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
 907 {
 908         struct snd_timer_id tid;
 909
 910         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
 911         tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
 912         tid.card = -1;
 913         tid.device = device;
 914         tid.subdevice = 0;
 915         return snd_timer_new(NULL, id, &tid, rtimer);
 916 }
 917
 918 int snd_timer_global_free(struct snd_timer *timer)
 919 {
 920         return snd_timer_free(timer);
 921 }
 922
 923 int snd_timer_global_register(struct snd_timer *timer)
 924 {
 925         struct snd_device dev;
 926
 927         memset(&dev, 0, sizeof(dev));
 928         dev.device_data = timer;
 929         return snd_timer_dev_register(&dev);
 930 }
 931
 932 /*
 933  *  System timer
 934  */
 935
 936 struct snd_timer_system_private {
 937         struct timer_list tlist;
 938         unsigned long last_expires;
 939         unsigned long last_jiffies;
 940         unsigned long correction;
 941 };
 942
 943 static void snd_timer_s_function(unsigned long data)
 944 {
 945         struct snd_timer *timer = (struct snd_timer *)data;
 946         struct snd_timer_system_private *priv = timer->private_data;
 947         unsigned long jiff = jiffies;
 948         if (time_after(jiff, priv->last_expires))
 949                 priv->correction += (long)jiff - (long)priv->last_expires;
 950         snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
 951 }
 952
 953 static int snd_timer_s_start(struct snd_timer * timer)
 954 {
 955         struct snd_timer_system_private *priv;
 956         unsigned long njiff;
 957
 958         priv = (struct snd_timer_system_private *) timer->private_data;
 959         njiff = (priv->last_jiffies = jiffies);
 960         if (priv->correction > timer->sticks - 1) {
 961                 priv->correction -= timer->sticks - 1;
 962                 njiff++;
 963         } else {
 964                 njiff += timer->sticks - priv->correction;
 965                 priv->correction = 0;
 966         }
 967         priv->last_expires = priv->tlist.expires = njiff;
 968         add_timer(&priv->tlist);
 969         return 0;
 970 }
 971
 972 static int snd_timer_s_stop(struct snd_timer * timer)
 973 {
 974         struct snd_timer_system_private *priv;
 975         unsigned long jiff;
 976
 977         priv = (struct snd_timer_system_private *) timer->private_data;
 978         del_timer(&priv->tlist);
 979         jiff = jiffies;
 980         if (time_before(jiff, priv->last_expires))
 981                 timer->sticks = priv->last_expires - jiff;
 982         else
 983                 timer->sticks = 1;
 984         priv->correction = 0;
 985         return 0;
 986 }
 987
 988 static struct snd_timer_hardware snd_timer_system =
 989 {
 990         .flags =        SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
 991         .resolution =   1000000000L / HZ,
 992         .ticks =        10000000L,
 993         .start =        snd_timer_s_start,
 994         .stop =         snd_timer_s_stop
 995 };
 996
 997 static void snd_timer_free_system(struct snd_timer *timer)
 998 {
 999         kfree(timer->private_data);
1000 }
1001
1002 static int snd_timer_register_system(void)
1003 {
1004         struct snd_timer *timer;
1005         struct snd_timer_system_private *priv;
1006         int err;
1007
1008         err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1009         if (err < 0)
1010                 return err;
1011         strcpy(timer->name, "system timer");
1012         timer->hw = snd_timer_system;
1013         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1014         if (priv == NULL) {
1015                 snd_timer_free(timer);
1016                 return -ENOMEM;
1017         }
1018         init_timer(&priv->tlist);
1019         priv->tlist.function = snd_timer_s_function;
1020         priv->tlist.data = (unsigned long) timer;
1021         timer->private_data = priv;
1022         timer->private_free = snd_timer_free_system;
1023         return snd_timer_global_register(timer);
1024 }
1025
1026 #ifdef CONFIG_PROC_FS
1027 /*
1028  *  Info interface
1029  */
1030
1031 static void snd_timer_proc_read(struct snd_info_entry *entry,
1032                                 struct snd_info_buffer *buffer)
1033 {
1034         struct snd_timer *timer;
1035         struct snd_timer_instance *ti;
1036
1037         mutex_lock(&register_mutex);
1038         list_for_each_entry(timer, &snd_timer_list, device_list) {
1039                 switch (timer->tmr_class) {
1040                 case SNDRV_TIMER_CLASS_GLOBAL:
1041                         snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1042                         break;
1043                 case SNDRV_TIMER_CLASS_CARD:
1044                         snd_iprintf(buffer, "C%i-%i: ",
1045                                     timer->card->number, timer->tmr_device);
1046                         break;
1047                 case SNDRV_TIMER_CLASS_PCM:
1048                         snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1049                                     timer->tmr_device, timer->tmr_subdevice);
1050                         break;
1051                 default:
1052                         snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1053                                     timer->card ? timer->card->number : -1,
1054                                     timer->tmr_device, timer->tmr_subdevice);
1055                 }
1056                 snd_iprintf(buffer, "%s :", timer->name);
1057                 if (timer->hw.resolution)
1058                         snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1059                                     timer->hw.resolution / 1000,
1060                                     timer->hw.resolution % 1000,
1061                                     timer->hw.ticks);
1062                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1063                         snd_iprintf(buffer, " SLAVE");
1064                 snd_iprintf(buffer, "\n");
1065                 list_for_each_entry(ti, &timer->open_list_head, open_list)
1066                         snd_iprintf(buffer, "  Client %s : %s\n",
1067                                     ti->owner ? ti->owner : "unknown",
1068                                     ti->flags & (SNDRV_TIMER_IFLG_START |
1069                                                  SNDRV_TIMER_IFLG_RUNNING)
1070                                     ? "running" : "stopped");
1071         }
1072         mutex_unlock(&register_mutex);
1073 }
1074
1075 static struct snd_info_entry *snd_timer_proc_entry;
1076
1077 static void __init snd_timer_proc_init(void)
1078 {
1079         struct snd_info_entry *entry;
1080
1081         entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1082         if (entry != NULL) {
1083                 entry->c.text.read = snd_timer_proc_read;
1084                 if (snd_info_register(entry) < 0) {
1085                         snd_info_free_entry(entry);
1086                         entry = NULL;
1087                 }
1088         }
1089         snd_timer_proc_entry = entry;
1090 }
1091
1092 static void __exit snd_timer_proc_done(void)
1093 {
1094         snd_info_free_entry(snd_timer_proc_entry);
1095 }
1096 #else /* !CONFIG_PROC_FS */
1097 #define snd_timer_proc_init()
1098 #define snd_timer_proc_done()
1099 #endif
1100
1101 /*
1102  *  USER SPACE interface
1103  */
1104
1105 static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1106                                      unsigned long resolution,
1107                                      unsigned long ticks)
1108 {
1109         struct snd_timer_user *tu = timeri->callback_data;
1110         struct snd_timer_read *r;
1111         int prev;
1112
1113         spin_lock(&tu->qlock);
1114         if (tu->qused > 0) {
1115                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1116                 r = &tu->queue[prev];
1117                 if (r->resolution == resolution) {
1118                         r->ticks += ticks;
1119                         goto __wake;
1120                 }
1121         }
1122         if (tu->qused >= tu->queue_size) {
1123                 tu->overrun++;
1124         } else {
1125                 r = &tu->queue[tu->qtail++];
1126                 tu->qtail %= tu->queue_size;
1127                 r->resolution = resolution;
1128                 r->ticks = ticks;
1129                 tu->qused++;
1130         }
1131       __wake:
1132         spin_unlock(&tu->qlock);
1133         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1134         wake_up(&tu->qchange_sleep);
1135 }
1136
1137 static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1138                                             struct snd_timer_tread *tread)
1139 {
1140         if (tu->qused >= tu->queue_size) {
1141                 tu->overrun++;
1142         } else {
1143                 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1144                 tu->qtail %= tu->queue_size;
1145                 tu->qused++;
1146         }
1147 }
1148
1149 static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1150                                      int event,
1151                                      struct timespec *tstamp,
1152                                      unsigned long resolution)
1153 {
1154         struct snd_timer_user *tu = timeri->callback_data;
1155         struct snd_timer_tread r1;
1156
1157         if (event >= SNDRV_TIMER_EVENT_START &&
1158             event <= SNDRV_TIMER_EVENT_PAUSE)
1159                 tu->tstamp = *tstamp;
1160         if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1161                 return;
1162         r1.event = event;
1163         r1.tstamp = *tstamp;
1164         r1.val = resolution;
1165         spin_lock(&tu->qlock);
1166         snd_timer_user_append_to_tqueue(tu, &r1);
1167         spin_unlock(&tu->qlock);
1168         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1169         wake_up(&tu->qchange_sleep);
1170 }
1171
1172 static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1173                                       unsigned long resolution,
1174                                       unsigned long ticks)
1175 {
1176         struct snd_timer_user *tu = timeri->callback_data;
1177         struct snd_timer_tread *r, r1;
1178         struct timespec tstamp;
1179         int prev, append = 0;
1180
1181         memset(&tstamp, 0, sizeof(tstamp));
1182         spin_lock(&tu->qlock);
1183         if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1184                            (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1185                 spin_unlock(&tu->qlock);
1186                 return;
1187         }
1188         if (tu->last_resolution != resolution || ticks > 0) {
1189                 if (timer_tstamp_monotonic)
1190                         do_posix_clock_monotonic_gettime(&tstamp);
1191                 else
1192                         getnstimeofday(&tstamp);
1193         }
1194         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1195             tu->last_resolution != resolution) {
1196                 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1197                 r1.tstamp = tstamp;
1198                 r1.val = resolution;
1199                 snd_timer_user_append_to_tqueue(tu, &r1);
1200                 tu->last_resolution = resolution;
1201                 append++;
1202         }
1203         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1204                 goto __wake;
1205         if (ticks == 0)
1206                 goto __wake;
1207         if (tu->qused > 0) {
1208                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1209                 r = &tu->tqueue[prev];
1210                 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1211                         r->tstamp = tstamp;
1212                         r->val += ticks;
1213                         append++;
1214                         goto __wake;
1215                 }
1216         }
1217         r1.event = SNDRV_TIMER_EVENT_TICK;
1218         r1.tstamp = tstamp;
1219         r1.val = ticks;
1220         snd_timer_user_append_to_tqueue(tu, &r1);
1221         append++;
1222       __wake:
1223         spin_unlock(&tu->qlock);
1224         if (append == 0)
1225                 return;
1226         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1227         wake_up(&tu->qchange_sleep);
1228 }
1229
1230 static int snd_timer_user_open(struct inode *inode, struct file *file)
1231 {
1232         struct snd_timer_user *tu;
1233
1234         tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1235         if (tu == NULL)
1236                 return -ENOMEM;
1237         spin_lock_init(&tu->qlock);
1238         init_waitqueue_head(&tu->qchange_sleep);
1239         mutex_init(&tu->tread_sem);
1240         tu->ticks = 1;
1241         tu->queue_size = 128;
1242         tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1243                             GFP_KERNEL);
1244         if (tu->queue == NULL) {
1245                 kfree(tu);
1246                 return -ENOMEM;
1247         }
1248         file->private_data = tu;
1249         return 0;
1250 }
1251
1252 static int snd_timer_user_release(struct inode *inode, struct file *file)
1253 {
1254         struct snd_timer_user *tu;
1255
1256         if (file->private_data) {
1257                 tu = file->private_data;
1258                 file->private_data = NULL;
1259                 fasync_helper(-1, file, 0, &tu->fasync);
1260                 if (tu->timeri)
1261                         snd_timer_close(tu->timeri);
1262                 kfree(tu->queue);
1263                 kfree(tu->tqueue);
1264                 kfree(tu);
1265         }
1266         return 0;
1267 }
1268
1269 static void snd_timer_user_zero_id(struct snd_timer_id *id)
1270 {
1271         id->dev_class = SNDRV_TIMER_CLASS_NONE;
1272         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1273         id->card = -1;
1274         id->device = -1;
1275         id->subdevice = -1;
1276 }
1277
1278 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1279 {
1280         id->dev_class = timer->tmr_class;
1281         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1282         id->card = timer->card ? timer->card->number : -1;
1283         id->device = timer->tmr_device;
1284         id->subdevice = timer->tmr_subdevice;
1285 }
1286
1287 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1288 {
1289         struct snd_timer_id id;
1290         struct snd_timer *timer;
1291         struct list_head *p;
1292
1293         if (copy_from_user(&id, _tid, sizeof(id)))
1294                 return -EFAULT;
1295         mutex_lock(&register_mutex);
1296         if (id.dev_class < 0) {         /* first item */
1297                 if (list_empty(&snd_timer_list))
1298                         snd_timer_user_zero_id(&id);
1299                 else {
1300                         timer = list_entry(snd_timer_list.next,
1301                                            struct snd_timer, device_list);
1302                         snd_timer_user_copy_id(&id, timer);
1303                 }
1304         } else {
1305                 switch (id.dev_class) {
1306                 case SNDRV_TIMER_CLASS_GLOBAL:
1307                         id.device = id.device < 0 ? 0 : id.device + 1;
1308                         list_for_each(p, &snd_timer_list) {
1309                                 timer = list_entry(p, struct snd_timer, device_list);
1310                                 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1311                                         snd_timer_user_copy_id(&id, timer);
1312                                         break;
1313                                 }
1314                                 if (timer->tmr_device >= id.device) {
1315                                         snd_timer_user_copy_id(&id, timer);
1316                                         break;
1317                                 }
1318                         }
1319                         if (p == &snd_timer_list)
1320                                 snd_timer_user_zero_id(&id);
1321                         break;
1322                 case SNDRV_TIMER_CLASS_CARD:
1323                 case SNDRV_TIMER_CLASS_PCM:
1324                         if (id.card < 0) {
1325                                 id.card = 0;
1326                         } else {
1327                                 if (id.card < 0) {
1328                                         id.card = 0;
1329                                 } else {
1330                                         if (id.device < 0) {
1331                                                 id.device = 0;
1332                                         } else {
1333                                                 if (id.subdevice < 0) {
1334                                                         id.subdevice = 0;
1335                                                 } else {
1336                                                         id.subdevice++;
1337                                                 }
1338                                         }
1339                                 }
1340                         }
1341                         list_for_each(p, &snd_timer_list) {
1342                                 timer = list_entry(p, struct snd_timer, device_list);
1343                                 if (timer->tmr_class > id.dev_class) {
1344                                         snd_timer_user_copy_id(&id, timer);
1345                                         break;
1346                                 }
1347                                 if (timer->tmr_class < id.dev_class)
1348                                         continue;
1349                                 if (timer->card->number > id.card) {
1350                                         snd_timer_user_copy_id(&id, timer);
1351                                         break;
1352                                 }
1353                                 if (timer->card->number < id.card)
1354                                         continue;
1355                                 if (timer->tmr_device > id.device) {
1356                                         snd_timer_user_copy_id(&id, timer);
1357                                         break;
1358                                 }
1359                                 if (timer->tmr_device < id.device)
1360                                         continue;
1361                                 if (timer->tmr_subdevice > id.subdevice) {
1362                                         snd_timer_user_copy_id(&id, timer);
1363                                         break;
1364                                 }
1365                                 if (timer->tmr_subdevice < id.subdevice)
1366                                         continue;
1367                                 snd_timer_user_copy_id(&id, timer);
1368                                 break;
1369                         }
1370                         if (p == &snd_timer_list)
1371                                 snd_timer_user_zero_id(&id);
1372                         break;
1373                 default:
1374                         snd_timer_user_zero_id(&id);
1375                 }
1376         }
1377         mutex_unlock(&register_mutex);
1378         if (copy_to_user(_tid, &id, sizeof(*_tid)))
1379                 return -EFAULT;
1380         return 0;
1381 }
1382
1383 static int snd_timer_user_ginfo(struct file *file,
1384                                 struct snd_timer_ginfo __user *_ginfo)
1385 {
1386         struct snd_timer_ginfo *ginfo;
1387         struct snd_timer_id tid;
1388         struct snd_timer *t;
1389         struct list_head *p;
1390         int err = 0;
1391
1392         ginfo = kmalloc(sizeof(*ginfo), GFP_KERNEL);
1393         if (! ginfo)
1394                 return -ENOMEM;
1395         if (copy_from_user(ginfo, _ginfo, sizeof(*ginfo))) {
1396                 kfree(ginfo);
1397                 return -EFAULT;
1398         }
1399         tid = ginfo->tid;
1400         memset(ginfo, 0, sizeof(*ginfo));
1401         ginfo->tid = tid;
1402         mutex_lock(&register_mutex);
1403         t = snd_timer_find(&tid);
1404         if (t != NULL) {
1405                 ginfo->card = t->card ? t->card->number : -1;
1406                 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1407                         ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1408                 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1409                 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1410                 ginfo->resolution = t->hw.resolution;
1411                 if (t->hw.resolution_min > 0) {
1412                         ginfo->resolution_min = t->hw.resolution_min;
1413                         ginfo->resolution_max = t->hw.resolution_max;
1414                 }
1415                 list_for_each(p, &t->open_list_head) {
1416                         ginfo->clients++;
1417                 }
1418         } else {
1419                 err = -ENODEV;
1420         }
1421         mutex_unlock(&register_mutex);
1422         if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1423                 err = -EFAULT;
1424         kfree(ginfo);
1425         return err;
1426 }
1427
1428 static int snd_timer_user_gparams(struct file *file,
1429                                   struct snd_timer_gparams __user *_gparams)
1430 {
1431         struct snd_timer_gparams gparams;
1432         struct snd_timer *t;
1433         int err;
1434
1435         if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1436                 return -EFAULT;
1437         mutex_lock(&register_mutex);
1438         t = snd_timer_find(&gparams.tid);
1439         if (!t) {
1440                 err = -ENODEV;
1441                 goto _error;
1442         }
1443         if (!list_empty(&t->open_list_head)) {
1444                 err = -EBUSY;
1445                 goto _error;
1446         }
1447         if (!t->hw.set_period) {
1448                 err = -ENOSYS;
1449                 goto _error;
1450         }
1451         err = t->hw.set_period(t, gparams.period_num, gparams.period_den);
1452 _error:
1453         mutex_unlock(&register_mutex);
1454         return err;
1455 }
1456
1457 static int snd_timer_user_gstatus(struct file *file,
1458                                   struct snd_timer_gstatus __user *_gstatus)
1459 {
1460         struct snd_timer_gstatus gstatus;
1461         struct snd_timer_id tid;
1462         struct snd_timer *t;
1463         int err = 0;
1464
1465         if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1466                 return -EFAULT;
1467         tid = gstatus.tid;
1468         memset(&gstatus, 0, sizeof(gstatus));
1469         gstatus.tid = tid;
1470         mutex_lock(&register_mutex);
1471         t = snd_timer_find(&tid);
1472         if (t != NULL) {
1473                 if (t->hw.c_resolution)
1474                         gstatus.resolution = t->hw.c_resolution(t);
1475                 else
1476                         gstatus.resolution = t->hw.resolution;
1477                 if (t->hw.precise_resolution) {
1478                         t->hw.precise_resolution(t, &gstatus.resolution_num,
1479                                                  &gstatus.resolution_den);
1480                 } else {
1481                         gstatus.resolution_num = gstatus.resolution;
1482                         gstatus.resolution_den = 1000000000uL;
1483                 }
1484         } else {
1485                 err = -ENODEV;
1486         }
1487         mutex_unlock(&register_mutex);
1488         if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1489                 err = -EFAULT;
1490         return err;
1491 }
1492
1493 static int snd_timer_user_tselect(struct file *file,
1494                                   struct snd_timer_select __user *_tselect)
1495 {
1496         struct snd_timer_user *tu;
1497         struct snd_timer_select tselect;
1498         char str[32];
1499         int err = 0;
1500
1501         tu = file->private_data;
1502         mutex_lock(&tu->tread_sem);
1503         if (tu->timeri) {
1504                 snd_timer_close(tu->timeri);
1505                 tu->timeri = NULL;
1506         }
1507         if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1508                 err = -EFAULT;
1509                 goto __err;
1510         }
1511         sprintf(str, "application %i", current->pid);
1512         if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1513                 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1514         err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1515         if (err < 0)
1516                 goto __err;
1517
1518         kfree(tu->queue);
1519         tu->queue = NULL;
1520         kfree(tu->tqueue);
1521         tu->tqueue = NULL;
1522         if (tu->tread) {
1523                 tu->tqueue = kmalloc(tu->queue_size * sizeof(struct snd_timer_tread),
1524                                      GFP_KERNEL);
1525                 if (tu->tqueue == NULL)
1526                         err = -ENOMEM;
1527         } else {
1528                 tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1529                                     GFP_KERNEL);
1530                 if (tu->queue == NULL)
1531                         err = -ENOMEM;
1532         }
1533
1534         if (err < 0) {
1535                 snd_timer_close(tu->timeri);
1536                 tu->timeri = NULL;
1537         } else {
1538                 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1539                 tu->timeri->callback = tu->tread
1540                         ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1541                 tu->timeri->ccallback = snd_timer_user_ccallback;
1542                 tu->timeri->callback_data = (void *)tu;
1543         }
1544
1545       __err:
1546         mutex_unlock(&tu->tread_sem);
1547         return err;
1548 }
1549
1550 static int snd_timer_user_info(struct file *file,
1551                                struct snd_timer_info __user *_info)
1552 {
1553         struct snd_timer_user *tu;
1554         struct snd_timer_info *info;
1555         struct snd_timer *t;
1556         int err = 0;
1557
1558         tu = file->private_data;
1559         if (!tu->timeri)
1560                 return -EBADFD;
1561         t = tu->timeri->timer;
1562         if (!t)
1563                 return -EBADFD;
1564
1565         info = kzalloc(sizeof(*info), GFP_KERNEL);
1566         if (! info)
1567                 return -ENOMEM;
1568         info->card = t->card ? t->card->number : -1;
1569         if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1570                 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1571         strlcpy(info->id, t->id, sizeof(info->id));
1572         strlcpy(info->name, t->name, sizeof(info->name));
1573         info->resolution = t->hw.resolution;
1574         if (copy_to_user(_info, info, sizeof(*_info)))
1575                 err = -EFAULT;
1576         kfree(info);
1577         return err;
1578 }
1579
1580 static int snd_timer_user_params(struct file *file,
1581                                  struct snd_timer_params __user *_params)
1582 {
1583         struct snd_timer_user *tu;
1584         struct snd_timer_params params;
1585         struct snd_timer *t;
1586         struct snd_timer_read *tr;
1587         struct snd_timer_tread *ttr;
1588         int err;
1589
1590         tu = file->private_data;
1591         if (!tu->timeri)
1592                 return -EBADFD;
1593         t = tu->timeri->timer;
1594         if (!t)
1595                 return -EBADFD;
1596         if (copy_from_user(&params, _params, sizeof(params)))
1597                 return -EFAULT;
1598         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE) && params.ticks < 1) {
1599                 err = -EINVAL;
1600                 goto _end;
1601         }
1602         if (params.queue_size > 0 &&
1603             (params.queue_size < 32 || params.queue_size > 1024)) {
1604                 err = -EINVAL;
1605                 goto _end;
1606         }
1607         if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1608                               (1<<SNDRV_TIMER_EVENT_TICK)|
1609                               (1<<SNDRV_TIMER_EVENT_START)|
1610                               (1<<SNDRV_TIMER_EVENT_STOP)|
1611                               (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1612                               (1<<SNDRV_TIMER_EVENT_PAUSE)|
1613                               (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1614                               (1<<SNDRV_TIMER_EVENT_RESUME)|
1615                               (1<<SNDRV_TIMER_EVENT_MSTART)|
1616                               (1<<SNDRV_TIMER_EVENT_MSTOP)|
1617                               (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1618                               (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1619                               (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1620                               (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1621                 err = -EINVAL;
1622                 goto _end;
1623         }
1624         snd_timer_stop(tu->timeri);
1625         spin_lock_irq(&t->lock);
1626         tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1627                                SNDRV_TIMER_IFLG_EXCLUSIVE|
1628                                SNDRV_TIMER_IFLG_EARLY_EVENT);
1629         if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1630                 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1631         if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1632                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1633         if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1634                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1635         spin_unlock_irq(&t->lock);
1636         if (params.queue_size > 0 &&
1637             (unsigned int)tu->queue_size != params.queue_size) {
1638                 if (tu->tread) {
1639                         ttr = kmalloc(params.queue_size * sizeof(*ttr),
1640                                       GFP_KERNEL);
1641                         if (ttr) {
1642                                 kfree(tu->tqueue);
1643                                 tu->queue_size = params.queue_size;
1644                                 tu->tqueue = ttr;
1645                         }
1646                 } else {
1647                         tr = kmalloc(params.queue_size * sizeof(*tr),
1648                                      GFP_KERNEL);
1649                         if (tr) {
1650                                 kfree(tu->queue);
1651                                 tu->queue_size = params.queue_size;
1652                                 tu->queue = tr;
1653                         }
1654                 }
1655         }
1656         tu->qhead = tu->qtail = tu->qused = 0;
1657         if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1658                 if (tu->tread) {
1659                         struct snd_timer_tread tread;
1660                         tread.event = SNDRV_TIMER_EVENT_EARLY;
1661                         tread.tstamp.tv_sec = 0;
1662                         tread.tstamp.tv_nsec = 0;
1663                         tread.val = 0;
1664                         snd_timer_user_append_to_tqueue(tu, &tread);
1665                 } else {
1666                         struct snd_timer_read *r = &tu->queue[0];
1667                         r->resolution = 0;
1668                         r->ticks = 0;
1669                         tu->qused++;
1670                         tu->qtail++;
1671                 }
1672         }
1673         tu->filter = params.filter;
1674         tu->ticks = params.ticks;
1675         err = 0;
1676  _end:
1677         if (copy_to_user(_params, &params, sizeof(params)))
1678                 return -EFAULT;
1679         return err;
1680 }
1681
1682 static int snd_timer_user_status(struct file *file,
1683                                  struct snd_timer_status __user *_status)
1684 {
1685         struct snd_timer_user *tu;
1686         struct snd_timer_status status;
1687
1688         tu = file->private_data;
1689         if (!tu->timeri)
1690                 return -EBADFD;
1691         memset(&status, 0, sizeof(status));
1692         status.tstamp = tu->tstamp;
1693         status.resolution = snd_timer_resolution(tu->timeri);
1694         status.lost = tu->timeri->lost;
1695         status.overrun = tu->overrun;
1696         spin_lock_irq(&tu->qlock);
1697         status.queue = tu->qused;
1698         spin_unlock_irq(&tu->qlock);
1699         if (copy_to_user(_status, &status, sizeof(status)))
1700                 return -EFAULT;
1701         return 0;
1702 }
1703
1704 static int snd_timer_user_start(struct file *file)
1705 {
1706         int err;
1707         struct snd_timer_user *tu;
1708
1709         tu = file->private_data;
1710         if (!tu->timeri)
1711                 return -EBADFD;
1712         snd_timer_stop(tu->timeri);
1713         tu->timeri->lost = 0;
1714         tu->last_resolution = 0;
1715         return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1716 }
1717
1718 static int snd_timer_user_stop(struct file *file)
1719 {
1720         int err;
1721         struct snd_timer_user *tu;
1722
1723         tu = file->private_data;
1724         if (!tu->timeri)
1725                 return -EBADFD;
1726         return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1727 }
1728
1729 static int snd_timer_user_continue(struct file *file)
1730 {
1731         int err;
1732         struct snd_timer_user *tu;
1733
1734         tu = file->private_data;
1735         if (!tu->timeri)
1736                 return -EBADFD;
1737         tu->timeri->lost = 0;
1738         return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1739 }
1740
1741 static int snd_timer_user_pause(struct file *file)
1742 {
1743         int err;
1744         struct snd_timer_user *tu;
1745
1746         tu = file->private_data;
1747         if (!tu->timeri)
1748                 return -EBADFD;
1749         return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1750 }
1751
1752 enum {
1753         SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1754         SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1755         SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1756         SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1757 };
1758
1759 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1760                                  unsigned long arg)
1761 {
1762         struct snd_timer_user *tu;
1763         void __user *argp = (void __user *)arg;
1764         int __user *p = argp;
1765
1766         tu = file->private_data;
1767         switch (cmd) {
1768         case SNDRV_TIMER_IOCTL_PVERSION:
1769                 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1770         case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1771                 return snd_timer_user_next_device(argp);
1772         case SNDRV_TIMER_IOCTL_TREAD:
1773         {
1774                 int xarg;
1775
1776                 mutex_lock(&tu->tread_sem);
1777                 if (tu->timeri) {       /* too late */
1778                         mutex_unlock(&tu->tread_sem);
1779                         return -EBUSY;
1780                 }
1781                 if (get_user(xarg, p)) {
1782                         mutex_unlock(&tu->tread_sem);
1783                         return -EFAULT;
1784                 }
1785                 tu->tread = xarg ? 1 : 0;
1786                 mutex_unlock(&tu->tread_sem);
1787                 return 0;
1788         }
1789         case SNDRV_TIMER_IOCTL_GINFO:
1790                 return snd_timer_user_ginfo(file, argp);
1791         case SNDRV_TIMER_IOCTL_GPARAMS:
1792                 return snd_timer_user_gparams(file, argp);
1793         case SNDRV_TIMER_IOCTL_GSTATUS:
1794                 return snd_timer_user_gstatus(file, argp);
1795         case SNDRV_TIMER_IOCTL_SELECT:
1796                 return snd_timer_user_tselect(file, argp);
1797         case SNDRV_TIMER_IOCTL_INFO:
1798                 return snd_timer_user_info(file, argp);
1799         case SNDRV_TIMER_IOCTL_PARAMS:
1800                 return snd_timer_user_params(file, argp);
1801         case SNDRV_TIMER_IOCTL_STATUS:
1802                 return snd_timer_user_status(file, argp);
1803         case SNDRV_TIMER_IOCTL_START:
1804         case SNDRV_TIMER_IOCTL_START_OLD:
1805                 return snd_timer_user_start(file);
1806         case SNDRV_TIMER_IOCTL_STOP:
1807         case SNDRV_TIMER_IOCTL_STOP_OLD:
1808                 return snd_timer_user_stop(file);
1809         case SNDRV_TIMER_IOCTL_CONTINUE:
1810         case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1811                 return snd_timer_user_continue(file);
1812         case SNDRV_TIMER_IOCTL_PAUSE:
1813         case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1814                 return snd_timer_user_pause(file);
1815         }
1816         return -ENOTTY;
1817 }
1818
1819 static int snd_timer_user_fasync(int fd, struct file * file, int on)
1820 {
1821         struct snd_timer_user *tu;
1822         int err;
1823
1824         tu = file->private_data;
1825         err = fasync_helper(fd, file, on, &tu->fasync);
1826         if (err < 0)
1827                 return err;
1828         return 0;
1829 }
1830
1831 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
1832                                    size_t count, loff_t *offset)
1833 {
1834         struct snd_timer_user *tu;
1835         long result = 0, unit;
1836         int err = 0;
1837
1838         tu = file->private_data;
1839         unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
1840         spin_lock_irq(&tu->qlock);
1841         while ((long)count - result >= unit) {
1842                 while (!tu->qused) {
1843                         wait_queue_t wait;
1844
1845                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1846                                 err = -EAGAIN;
1847                                 break;
1848                         }
1849
1850                         set_current_state(TASK_INTERRUPTIBLE);
1851                         init_waitqueue_entry(&wait, current);
1852                         add_wait_queue(&tu->qchange_sleep, &wait);
1853
1854                         spin_unlock_irq(&tu->qlock);
1855                         schedule();
1856                         spin_lock_irq(&tu->qlock);
1857
1858                         remove_wait_queue(&tu->qchange_sleep, &wait);
1859
1860                         if (signal_pending(current)) {
1861                                 err = -ERESTARTSYS;
1862                                 break;
1863                         }
1864                 }
1865
1866                 spin_unlock_irq(&tu->qlock);
1867                 if (err < 0)
1868                         goto _error;
1869
1870                 if (tu->tread) {
1871                         if (copy_to_user(buffer, &tu->tqueue[tu->qhead++],
1872                                          sizeof(struct snd_timer_tread))) {
1873                                 err = -EFAULT;
1874                                 goto _error;
1875                         }
1876                 } else {
1877                         if (copy_to_user(buffer, &tu->queue[tu->qhead++],
1878                                          sizeof(struct snd_timer_read))) {
1879                                 err = -EFAULT;
1880                                 goto _error;
1881                         }
1882                 }
1883
1884                 tu->qhead %= tu->queue_size;
1885
1886                 result += unit;
1887                 buffer += unit;
1888
1889                 spin_lock_irq(&tu->qlock);
1890                 tu->qused--;
1891         }
1892         spin_unlock_irq(&tu->qlock);
1893  _error:
1894         return result > 0 ? result : err;
1895 }
1896
1897 static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
1898 {
1899         unsigned int mask;
1900         struct snd_timer_user *tu;
1901
1902         tu = file->private_data;
1903
1904         poll_wait(file, &tu->qchange_sleep, wait);
1905
1906         mask = 0;
1907         if (tu->qused)
1908                 mask |= POLLIN | POLLRDNORM;
1909
1910         return mask;
1911 }
1912
1913 #ifdef CONFIG_COMPAT
1914 #include "timer_compat.c"
1915 #else
1916 #define snd_timer_user_ioctl_compat     NULL
1917 #endif
1918
1919 static const struct file_operations snd_timer_f_ops =
1920 {
1921         .owner =        THIS_MODULE,
1922         .read =         snd_timer_user_read,
1923         .open =         snd_timer_user_open,
1924         .release =      snd_timer_user_release,
1925         .poll =         snd_timer_user_poll,
1926         .unlocked_ioctl =       snd_timer_user_ioctl,
1927         .compat_ioctl = snd_timer_user_ioctl_compat,
1928         .fasync =       snd_timer_user_fasync,
1929 };
1930
1931 /*
1932  *  ENTRY functions
1933  */
1934
1935 static int __init alsa_timer_init(void)
1936 {
1937         int err;
1938
1939 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
1940         snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
1941                               "system timer");
1942 #endif
1943
1944         if ((err = snd_timer_register_system()) < 0)
1945                 snd_printk(KERN_ERR "unable to register system timer (%i)\n",
1946                            err);
1947         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
1948                                        &snd_timer_f_ops, NULL, "timer")) < 0)
1949                 snd_printk(KERN_ERR "unable to register timer device (%i)\n",
1950                            err);
1951         snd_timer_proc_init();
1952         return 0;
1953 }
1954
1955 static void __exit alsa_timer_exit(void)
1956 {
1957         struct list_head *p, *n;
1958
1959         snd_unregister_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0);
1960         /* unregister the system timer */
1961         list_for_each_safe(p, n, &snd_timer_list) {
1962                 struct snd_timer *timer = list_entry(p, struct snd_timer, device_list);
1963                 snd_timer_free(timer);
1964         }
1965         snd_timer_proc_done();
1966 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
1967         snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
1968 #endif
1969 }
1970
1971 module_init(alsa_timer_init)
1972 module_exit(alsa_timer_exit)
1973
1974 EXPORT_SYMBOL(snd_timer_open);
1975 EXPORT_SYMBOL(snd_timer_close);
1976 EXPORT_SYMBOL(snd_timer_resolution);
1977 EXPORT_SYMBOL(snd_timer_start);
1978 EXPORT_SYMBOL(snd_timer_stop);
1979 EXPORT_SYMBOL(snd_timer_continue);
1980 EXPORT_SYMBOL(snd_timer_pause);
1981 EXPORT_SYMBOL(snd_timer_new);
1982 EXPORT_SYMBOL(snd_timer_notify);
1983 EXPORT_SYMBOL(snd_timer_global_new);
1984 EXPORT_SYMBOL(snd_timer_global_free);
1985 EXPORT_SYMBOL(snd_timer_global_register);
1986 EXPORT_SYMBOL(snd_timer_interrupt);