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 #ifdef CONFIG_KERNELD
  39 #include <linux/kerneld.h>
  40 #endif
  41
  42 #if defined(CONFIG_SND_HPET) || defined(CONFIG_SND_HPET_MODULE)
  43 #define DEFAULT_TIMER_LIMIT 3
  44 #elif defined(CONFIG_SND_RTCTIMER) || defined(CONFIG_SND_RTCTIMER_MODULE)
  45 #define DEFAULT_TIMER_LIMIT 2
  46 #else
  47 #define DEFAULT_TIMER_LIMIT 1
  48 #endif
  49
  50 static int timer_limit = DEFAULT_TIMER_LIMIT;
  51 MODULE_AUTHOR("Jaroslav Kysela <perex@suse.cz>, Takashi Iwai <tiwai@suse.de>");
  52 MODULE_DESCRIPTION("ALSA timer interface");
  53 MODULE_LICENSE("GPL");
  54 module_param(timer_limit, int, 0444);
  55 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
  56
  57 struct snd_timer_user {
  58         struct snd_timer_instance *timeri;
  59         int tread;              /* enhanced read with timestamps and events */
  60         unsigned long ticks;
  61         unsigned long overrun;
  62         int qhead;
  63         int qtail;
  64         int qused;
  65         int queue_size;
  66         struct snd_timer_read *queue;
  67         struct snd_timer_tread *tqueue;
  68         spinlock_t qlock;
  69         unsigned long last_resolution;
  70         unsigned int filter;
  71         struct timespec tstamp;         /* trigger tstamp */
  72         wait_queue_head_t qchange_sleep;
  73         struct fasync_struct *fasync;
  74         struct mutex tread_sem;
  75 };
  76
  77 /* list of timers */
  78 static LIST_HEAD(snd_timer_list);
  79
  80 /* list of slave instances */
  81 static LIST_HEAD(snd_timer_slave_list);
  82
  83 /* lock for slave active lists */
  84 static DEFINE_SPINLOCK(slave_active_lock);
  85
  86 static DEFINE_MUTEX(register_mutex);
  87
  88 static int snd_timer_free(struct snd_timer *timer);
  89 static int snd_timer_dev_free(struct snd_device *device);
  90 static int snd_timer_dev_register(struct snd_device *device);
  91 static int snd_timer_dev_disconnect(struct snd_device *device);
  92
  93 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
  94
  95 /*
  96  * create a timer instance with the given owner string.
  97  * when timer is not NULL, increments the module counter
  98  */
  99 static struct snd_timer_instance *snd_timer_instance_new(char *owner,
 100                                                          struct snd_timer *timer)
 101 {
 102         struct snd_timer_instance *timeri;
 103         timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
 104         if (timeri == NULL)
 105                 return NULL;
 106         timeri->owner = kstrdup(owner, GFP_KERNEL);
 107         if (! timeri->owner) {
 108                 kfree(timeri);
 109                 return NULL;
 110         }
 111         INIT_LIST_HEAD(&timeri->open_list);
 112         INIT_LIST_HEAD(&timeri->active_list);
 113         INIT_LIST_HEAD(&timeri->ack_list);
 114         INIT_LIST_HEAD(&timeri->slave_list_head);
 115         INIT_LIST_HEAD(&timeri->slave_active_head);
 116
 117         timeri->timer = timer;
 118         if (timer && !try_module_get(timer->module)) {
 119                 kfree(timeri->owner);
 120                 kfree(timeri);
 121                 return NULL;
 122         }
 123
 124         return timeri;
 125 }
 126
 127 /*
 128  * find a timer instance from the given timer id
 129  */
 130 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
 131 {
 132         struct snd_timer *timer = NULL;
 133         struct list_head *p;
 134
 135         list_for_each(p, &snd_timer_list) {
 136                 timer = list_entry(p, struct snd_timer, device_list);
 137
 138                 if (timer->tmr_class != tid->dev_class)
 139                         continue;
 140                 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
 141                      timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
 142                     (timer->card == NULL ||
 143                      timer->card->number != tid->card))
 144                         continue;
 145                 if (timer->tmr_device != tid->device)
 146                         continue;
 147                 if (timer->tmr_subdevice != tid->subdevice)
 148                         continue;
 149                 return timer;
 150         }
 151         return NULL;
 152 }
 153
 154 #ifdef CONFIG_KMOD
 155
 156 static void snd_timer_request(struct snd_timer_id *tid)
 157 {
 158         if (! current->fs->root)
 159                 return;
 160         switch (tid->dev_class) {
 161         case SNDRV_TIMER_CLASS_GLOBAL:
 162                 if (tid->device < timer_limit)
 163                         request_module("snd-timer-%i", tid->device);
 164                 break;
 165         case SNDRV_TIMER_CLASS_CARD:
 166         case SNDRV_TIMER_CLASS_PCM:
 167                 if (tid->card < snd_ecards_limit)
 168                         request_module("snd-card-%i", tid->card);
 169                 break;
 170         default:
 171                 break;
 172         }
 173 }
 174
 175 #endif
 176
 177 /*
 178  * look for a master instance matching with the slave id of the given slave.
 179  * when found, relink the open_link of the slave.
 180  *
 181  * call this with register_mutex down.
 182  */
 183 static void snd_timer_check_slave(struct snd_timer_instance *slave)
 184 {
 185         struct snd_timer *timer;
 186         struct snd_timer_instance *master;
 187         struct list_head *p, *q;
 188
 189         /* FIXME: it's really dumb to look up all entries.. */
 190         list_for_each(p, &snd_timer_list) {
 191                 timer = list_entry(p, struct snd_timer, device_list);
 192                 list_for_each(q, &timer->open_list_head) {
 193                         master = list_entry(q, struct snd_timer_instance, open_list);
 194                         if (slave->slave_class == master->slave_class &&
 195                             slave->slave_id == master->slave_id) {
 196                                 list_del(&slave->open_list);
 197                                 list_add_tail(&slave->open_list,
 198                                               &master->slave_list_head);
 199                                 spin_lock_irq(&slave_active_lock);
 200                                 slave->master = master;
 201                                 slave->timer = master->timer;
 202                                 spin_unlock_irq(&slave_active_lock);
 203                                 return;
 204                         }
 205                 }
 206         }
 207 }
 208
 209 /*
 210  * look for slave instances matching with the slave id of the given master.
 211  * when found, relink the open_link of slaves.
 212  *
 213  * call this with register_mutex down.
 214  */
 215 static void snd_timer_check_master(struct snd_timer_instance *master)
 216 {
 217         struct snd_timer_instance *slave;
 218         struct list_head *p, *n;
 219
 220         /* check all pending slaves */
 221         list_for_each_safe(p, n, &snd_timer_slave_list) {
 222                 slave = list_entry(p, struct snd_timer_instance, open_list);
 223                 if (slave->slave_class == master->slave_class &&
 224                     slave->slave_id == master->slave_id) {
 225                         list_del(p);
 226                         list_add_tail(p, &master->slave_list_head);
 227                         spin_lock_irq(&slave_active_lock);
 228                         slave->master = master;
 229                         slave->timer = master->timer;
 230                         if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
 231                                 list_add_tail(&slave->active_list,
 232                                               &master->slave_active_head);
 233                         spin_unlock_irq(&slave_active_lock);
 234                 }
 235         }
 236 }
 237
 238 /*
 239  * open a timer instance
 240  * when opening a master, the slave id must be here given.
 241  */
 242 int snd_timer_open(struct snd_timer_instance **ti,
 243                    char *owner, struct snd_timer_id *tid,
 244                    unsigned int slave_id)
 245 {
 246         struct snd_timer *timer;
 247         struct snd_timer_instance *timeri = NULL;
 248
 249         if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
 250                 /* open a slave instance */
 251                 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
 252                     tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
 253                         snd_printd("invalid slave class %i\n", tid->dev_sclass);
 254                         return -EINVAL;
 255                 }
 256                 mutex_lock(&register_mutex);
 257                 timeri = snd_timer_instance_new(owner, NULL);
 258                 if (!timeri) {
 259                         mutex_unlock(&register_mutex);
 260                         return -ENOMEM;
 261                 }
 262                 timeri->slave_class = tid->dev_sclass;
 263                 timeri->slave_id = tid->device;
 264                 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
 265                 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
 266                 snd_timer_check_slave(timeri);
 267                 mutex_unlock(&register_mutex);
 268                 *ti = timeri;
 269                 return 0;
 270         }
 271
 272         /* open a master instance */
 273         mutex_lock(&register_mutex);
 274         timer = snd_timer_find(tid);
 275 #ifdef CONFIG_KMOD
 276         if (timer == NULL) {
 277                 mutex_unlock(&register_mutex);
 278                 snd_timer_request(tid);
 279                 mutex_lock(&register_mutex);
 280                 timer = snd_timer_find(tid);
 281         }
 282 #endif
 283         if (!timer) {
 284                 mutex_unlock(&register_mutex);
 285                 return -ENODEV;
 286         }
 287         if (!list_empty(&timer->open_list_head)) {
 288                 timeri = list_entry(timer->open_list_head.next,
 289                                     struct snd_timer_instance, open_list);
 290                 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
 291                         mutex_unlock(&register_mutex);
 292                         return -EBUSY;
 293                 }
 294         }
 295         timeri = snd_timer_instance_new(owner, timer);
 296         if (!timeri) {
 297                 mutex_unlock(&register_mutex);
 298                 return -ENOMEM;
 299         }
 300         timeri->slave_class = tid->dev_sclass;
 301         timeri->slave_id = slave_id;
 302         if (list_empty(&timer->open_list_head) && timer->hw.open)
 303                 timer->hw.open(timer);
 304         list_add_tail(&timeri->open_list, &timer->open_list_head);
 305         snd_timer_check_master(timeri);
 306         mutex_unlock(&register_mutex);
 307         *ti = timeri;
 308         return 0;
 309 }
 310
 311 static int _snd_timer_stop(struct snd_timer_instance *timeri,
 312                            int keep_flag, int event);
 313
 314 /*
 315  * close a timer instance
 316  */
 317 int snd_timer_close(struct snd_timer_instance *timeri)
 318 {
 319         struct snd_timer *timer = NULL;
 320         struct list_head *p, *n;
 321         struct snd_timer_instance *slave;
 322
 323         snd_assert(timeri != NULL, return -ENXIO);
 324
 325         /* force to stop the timer */
 326         snd_timer_stop(timeri);
 327
 328         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 329                 /* wait, until the active callback is finished */
 330                 spin_lock_irq(&slave_active_lock);
 331                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 332                         spin_unlock_irq(&slave_active_lock);
 333                         udelay(10);
 334                         spin_lock_irq(&slave_active_lock);
 335                 }
 336                 spin_unlock_irq(&slave_active_lock);
 337                 mutex_lock(&register_mutex);
 338                 list_del(&timeri->open_list);
 339                 mutex_unlock(&register_mutex);
 340         } else {
 341                 timer = timeri->timer;
 342                 /* wait, until the active callback is finished */
 343                 spin_lock_irq(&timer->lock);
 344                 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 345                         spin_unlock_irq(&timer->lock);
 346                         udelay(10);
 347                         spin_lock_irq(&timer->lock);
 348                 }
 349                 spin_unlock_irq(&timer->lock);
 350                 mutex_lock(&register_mutex);
 351                 list_del(&timeri->open_list);
 352                 if (timer && list_empty(&timer->open_list_head) &&
 353                     timer->hw.close)
 354                         timer->hw.close(timer);
 355                 /* remove slave links */
 356                 list_for_each_safe(p, n, &timeri->slave_list_head) {
 357                         slave = list_entry(p, struct snd_timer_instance, open_list);
 358                         spin_lock_irq(&slave_active_lock);
 359                         _snd_timer_stop(slave, 1, SNDRV_TIMER_EVENT_RESOLUTION);
 360                         list_del(p);
 361                         list_add_tail(p, &snd_timer_slave_list);
 362                         slave->master = NULL;
 363                         slave->timer = NULL;
 364                         spin_unlock_irq(&slave_active_lock);
 365                 }
 366                 mutex_unlock(&register_mutex);
 367         }
 368         if (timeri->private_free)
 369                 timeri->private_free(timeri);
 370         kfree(timeri->owner);
 371         kfree(timeri);
 372         if (timer)
 373                 module_put(timer->module);
 374         return 0;
 375 }
 376
 377 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
 378 {
 379         struct snd_timer * timer;
 380
 381         if (timeri == NULL)
 382                 return 0;
 383         if ((timer = timeri->timer) != NULL) {
 384                 if (timer->hw.c_resolution)
 385                         return timer->hw.c_resolution(timer);
 386                 return timer->hw.resolution;
 387         }
 388         return 0;
 389 }
 390
 391 static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
 392 {
 393         struct snd_timer *timer;
 394         unsigned long flags;
 395         unsigned long resolution = 0;
 396         struct snd_timer_instance *ts;
 397         struct list_head *n;
 398         struct timespec tstamp;
 399
 400         getnstimeofday(&tstamp);
 401         snd_assert(event >= SNDRV_TIMER_EVENT_START &&
 402                    event <= SNDRV_TIMER_EVENT_PAUSE, return);
 403         if (event == SNDRV_TIMER_EVENT_START ||
 404             event == SNDRV_TIMER_EVENT_CONTINUE)
 405                 resolution = snd_timer_resolution(ti);
 406         if (ti->ccallback)
 407                 ti->ccallback(ti, SNDRV_TIMER_EVENT_START, &tstamp, resolution);
 408         if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
 409                 return;
 410         timer = ti->timer;
 411         if (timer == NULL)
 412                 return;
 413         if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 414                 return;
 415         spin_lock_irqsave(&timer->lock, flags);
 416         list_for_each(n, &ti->slave_active_head) {
 417                 ts = list_entry(n, struct snd_timer_instance, active_list);
 418                 if (ts->ccallback)
 419                         ts->ccallback(ti, event + 100, &tstamp, resolution);
 420         }
 421         spin_unlock_irqrestore(&timer->lock, flags);
 422 }
 423
 424 static int snd_timer_start1(struct snd_timer *timer, struct snd_timer_instance *timeri,
 425                             unsigned long sticks)
 426 {
 427         list_del(&timeri->active_list);
 428         list_add_tail(&timeri->active_list, &timer->active_list_head);
 429         if (timer->running) {
 430                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 431                         goto __start_now;
 432                 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
 433                 timeri->flags |= SNDRV_TIMER_IFLG_START;
 434                 return 1;       /* delayed start */
 435         } else {
 436                 timer->sticks = sticks;
 437                 timer->hw.start(timer);
 438               __start_now:
 439                 timer->running++;
 440                 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 441                 return 0;
 442         }
 443 }
 444
 445 static int snd_timer_start_slave(struct snd_timer_instance *timeri)
 446 {
 447         unsigned long flags;
 448
 449         spin_lock_irqsave(&slave_active_lock, flags);
 450         timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 451         if (timeri->master)
 452                 list_add_tail(&timeri->active_list,
 453                               &timeri->master->slave_active_head);
 454         spin_unlock_irqrestore(&slave_active_lock, flags);
 455         return 1; /* delayed start */
 456 }
 457
 458 /*
 459  *  start the timer instance
 460  */
 461 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
 462 {
 463         struct snd_timer *timer;
 464         int result = -EINVAL;
 465         unsigned long flags;
 466
 467         if (timeri == NULL || ticks < 1)
 468                 return -EINVAL;
 469         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 470                 result = snd_timer_start_slave(timeri);
 471                 snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
 472                 return result;
 473         }
 474         timer = timeri->timer;
 475         if (timer == NULL)
 476                 return -EINVAL;
 477         spin_lock_irqsave(&timer->lock, flags);
 478         timeri->ticks = timeri->cticks = ticks;
 479         timeri->pticks = 0;
 480         result = snd_timer_start1(timer, timeri, ticks);
 481         spin_unlock_irqrestore(&timer->lock, flags);
 482         snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_START);
 483         return result;
 484 }
 485
 486 static int _snd_timer_stop(struct snd_timer_instance * timeri,
 487                            int keep_flag, int event)
 488 {
 489         struct snd_timer *timer;
 490         unsigned long flags;
 491
 492         snd_assert(timeri != NULL, return -ENXIO);
 493
 494         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) {
 495                 if (!keep_flag) {
 496                         spin_lock_irqsave(&slave_active_lock, flags);
 497                         timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 498                         spin_unlock_irqrestore(&slave_active_lock, flags);
 499                 }
 500                 goto __end;
 501         }
 502         timer = timeri->timer;
 503         if (!timer)
 504                 return -EINVAL;
 505         spin_lock_irqsave(&timer->lock, flags);
 506         list_del_init(&timeri->ack_list);
 507         list_del_init(&timeri->active_list);
 508         if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
 509             !(--timer->running)) {
 510                 timer->hw.stop(timer);
 511                 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
 512                         timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 513                         snd_timer_reschedule(timer, 0);
 514                         if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
 515                                 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 516                                 timer->hw.start(timer);
 517                         }
 518                 }
 519         }
 520         if (!keep_flag)
 521                 timeri->flags &=
 522                         ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
 523         spin_unlock_irqrestore(&timer->lock, flags);
 524       __end:
 525         if (event != SNDRV_TIMER_EVENT_RESOLUTION)
 526                 snd_timer_notify1(timeri, event);
 527         return 0;
 528 }
 529
 530 /*
 531  * stop the timer instance.
 532  *
 533  * do not call this from the timer callback!
 534  */
 535 int snd_timer_stop(struct snd_timer_instance *timeri)
 536 {
 537         struct snd_timer *timer;
 538         unsigned long flags;
 539         int err;
 540
 541         err = _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_STOP);
 542         if (err < 0)
 543                 return err;
 544         timer = timeri->timer;
 545         spin_lock_irqsave(&timer->lock, flags);
 546         timeri->cticks = timeri->ticks;
 547         timeri->pticks = 0;
 548         spin_unlock_irqrestore(&timer->lock, flags);
 549         return 0;
 550 }
 551
 552 /*
 553  * start again..  the tick is kept.
 554  */
 555 int snd_timer_continue(struct snd_timer_instance *timeri)
 556 {
 557         struct snd_timer *timer;
 558         int result = -EINVAL;
 559         unsigned long flags;
 560
 561         if (timeri == NULL)
 562                 return result;
 563         if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 564                 return snd_timer_start_slave(timeri);
 565         timer = timeri->timer;
 566         if (! timer)
 567                 return -EINVAL;
 568         spin_lock_irqsave(&timer->lock, flags);
 569         if (!timeri->cticks)
 570                 timeri->cticks = 1;
 571         timeri->pticks = 0;
 572         result = snd_timer_start1(timer, timeri, timer->sticks);
 573         spin_unlock_irqrestore(&timer->lock, flags);
 574         snd_timer_notify1(timeri, SNDRV_TIMER_EVENT_CONTINUE);
 575         return result;
 576 }
 577
 578 /*
 579  * pause.. remember the ticks left
 580  */
 581 int snd_timer_pause(struct snd_timer_instance * timeri)
 582 {
 583         return _snd_timer_stop(timeri, 0, SNDRV_TIMER_EVENT_PAUSE);
 584 }
 585
 586 /*
 587  * reschedule the timer
 588  *
 589  * start pending instances and check the scheduling ticks.
 590  * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
 591  */
 592 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
 593 {
 594         struct snd_timer_instance *ti;
 595         unsigned long ticks = ~0UL;
 596         struct list_head *p;
 597
 598         list_for_each(p, &timer->active_list_head) {
 599                 ti = list_entry(p, struct snd_timer_instance, active_list);
 600                 if (ti->flags & SNDRV_TIMER_IFLG_START) {
 601                         ti->flags &= ~SNDRV_TIMER_IFLG_START;
 602                         ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
 603                         timer->running++;
 604                 }
 605                 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
 606                         if (ticks > ti->cticks)
 607                                 ticks = ti->cticks;
 608                 }
 609         }
 610         if (ticks == ~0UL) {
 611                 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 612                 return;
 613         }
 614         if (ticks > timer->hw.ticks)
 615                 ticks = timer->hw.ticks;
 616         if (ticks_left != ticks)
 617                 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 618         timer->sticks = ticks;
 619 }
 620
 621 /*
 622  * timer tasklet
 623  *
 624  */
 625 static void snd_timer_tasklet(unsigned long arg)
 626 {
 627         struct snd_timer *timer = (struct snd_timer *) arg;
 628         struct snd_timer_instance *ti;
 629         struct list_head *p;
 630         unsigned long resolution, ticks;
 631         unsigned long flags;
 632
 633         spin_lock_irqsave(&timer->lock, flags);
 634         /* now process all callbacks */
 635         while (!list_empty(&timer->sack_list_head)) {
 636                 p = timer->sack_list_head.next;         /* get first item */
 637                 ti = list_entry(p, struct snd_timer_instance, ack_list);
 638
 639                 /* remove from ack_list and make empty */
 640                 list_del_init(p);
 641
 642                 ticks = ti->pticks;
 643                 ti->pticks = 0;
 644                 resolution = ti->resolution;
 645
 646                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 647                 spin_unlock(&timer->lock);
 648                 if (ti->callback)
 649                         ti->callback(ti, resolution, ticks);
 650                 spin_lock(&timer->lock);
 651                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 652         }
 653         spin_unlock_irqrestore(&timer->lock, flags);
 654 }
 655
 656 /*
 657  * timer interrupt
 658  *
 659  * ticks_left is usually equal to timer->sticks.
 660  *
 661  */
 662 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
 663 {
 664         struct snd_timer_instance *ti, *ts;
 665         unsigned long resolution, ticks;
 666         struct list_head *p, *q, *n, *ack_list_head;
 667         unsigned long flags;
 668         int use_tasklet = 0;
 669
 670         if (timer == NULL)
 671                 return;
 672
 673         spin_lock_irqsave(&timer->lock, flags);
 674
 675         /* remember the current resolution */
 676         if (timer->hw.c_resolution)
 677                 resolution = timer->hw.c_resolution(timer);
 678         else
 679                 resolution = timer->hw.resolution;
 680
 681         /* loop for all active instances
 682          * Here we cannot use list_for_each because the active_list of a
 683          * processed instance is relinked to done_list_head before the callback
 684          * is called.
 685          */
 686         list_for_each_safe(p, n, &timer->active_list_head) {
 687                 ti = list_entry(p, struct snd_timer_instance, active_list);
 688                 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
 689                         continue;
 690                 ti->pticks += ticks_left;
 691                 ti->resolution = resolution;
 692                 if (ti->cticks < ticks_left)
 693                         ti->cticks = 0;
 694                 else
 695                         ti->cticks -= ticks_left;
 696                 if (ti->cticks) /* not expired */
 697                         continue;
 698                 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
 699                         ti->cticks = ti->ticks;
 700                 } else {
 701                         ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 702                         if (--timer->running)
 703                                 list_del(p);
 704                 }
 705                 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
 706                     (ti->flags & SNDRV_TIMER_IFLG_FAST))
 707                         ack_list_head = &timer->ack_list_head;
 708                 else
 709                         ack_list_head = &timer->sack_list_head;
 710                 if (list_empty(&ti->ack_list))
 711                         list_add_tail(&ti->ack_list, ack_list_head);
 712                 list_for_each(q, &ti->slave_active_head) {
 713                         ts = list_entry(q, struct snd_timer_instance, active_list);
 714                         ts->pticks = ti->pticks;
 715                         ts->resolution = resolution;
 716                         if (list_empty(&ts->ack_list))
 717                                 list_add_tail(&ts->ack_list, ack_list_head);
 718                 }
 719         }
 720         if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
 721                 snd_timer_reschedule(timer, timer->sticks);
 722         if (timer->running) {
 723                 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
 724                         timer->hw.stop(timer);
 725                         timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 726                 }
 727                 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
 728                     (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
 729                         /* restart timer */
 730                         timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 731                         timer->hw.start(timer);
 732                 }
 733         } else {
 734                 timer->hw.stop(timer);
 735         }
 736
 737         /* now process all fast callbacks */
 738         while (!list_empty(&timer->ack_list_head)) {
 739                 p = timer->ack_list_head.next;          /* get first item */
 740                 ti = list_entry(p, struct snd_timer_instance, ack_list);
 741
 742                 /* remove from ack_list and make empty */
 743                 list_del_init(p);
 744
 745                 ticks = ti->pticks;
 746                 ti->pticks = 0;
 747
 748                 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 749                 spin_unlock(&timer->lock);
 750                 if (ti->callback)
 751                         ti->callback(ti, resolution, ticks);
 752                 spin_lock(&timer->lock);
 753                 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 754         }
 755
 756         /* do we have any slow callbacks? */
 757         use_tasklet = !list_empty(&timer->sack_list_head);
 758         spin_unlock_irqrestore(&timer->lock, flags);
 759
 760         if (use_tasklet)
 761                 tasklet_hi_schedule(&timer->task_queue);
 762 }
 763
 764 /*
 765
 766  */
 767
 768 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
 769                   struct snd_timer **rtimer)
 770 {
 771         struct snd_timer *timer;
 772         int err;
 773         static struct snd_device_ops ops = {
 774                 .dev_free = snd_timer_dev_free,
 775                 .dev_register = snd_timer_dev_register,
 776                 .dev_disconnect = snd_timer_dev_disconnect,
 777         };
 778
 779         snd_assert(tid != NULL, return -EINVAL);
 780         snd_assert(rtimer != NULL, return -EINVAL);
 781         *rtimer = NULL;
 782         timer = kzalloc(sizeof(*timer), GFP_KERNEL);
 783         if (timer == NULL) {
 784                 snd_printk(KERN_ERR "timer: cannot allocate\n");
 785                 return -ENOMEM;
 786         }
 787         timer->tmr_class = tid->dev_class;
 788         timer->card = card;
 789         timer->tmr_device = tid->device;
 790         timer->tmr_subdevice = tid->subdevice;
 791         if (id)
 792                 strlcpy(timer->id, id, sizeof(timer->id));
 793         INIT_LIST_HEAD(&timer->device_list);
 794         INIT_LIST_HEAD(&timer->open_list_head);
 795         INIT_LIST_HEAD(&timer->active_list_head);
 796         INIT_LIST_HEAD(&timer->ack_list_head);
 797         INIT_LIST_HEAD(&timer->sack_list_head);
 798         spin_lock_init(&timer->lock);
 799         tasklet_init(&timer->task_queue, snd_timer_tasklet,
 800                      (unsigned long)timer);
 801         if (card != NULL) {
 802                 timer->module = card->module;
 803                 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
 804                 if (err < 0) {
 805                         snd_timer_free(timer);
 806                         return err;
 807                 }
 808         }
 809         *rtimer = timer;
 810         return 0;
 811 }
 812
 813 static int snd_timer_free(struct snd_timer *timer)
 814 {
 815         snd_assert(timer != NULL, return -ENXIO);
 816
 817         mutex_lock(&register_mutex);
 818         if (! list_empty(&timer->open_list_head)) {
 819                 struct list_head *p, *n;
 820                 struct snd_timer_instance *ti;
 821                 snd_printk(KERN_WARNING "timer %p is busy?\n", timer);
 822                 list_for_each_safe(p, n, &timer->open_list_head) {
 823                         list_del_init(p);
 824                         ti = list_entry(p, struct snd_timer_instance, open_list);
 825                         ti->timer = NULL;
 826                 }
 827         }
 828         list_del(&timer->device_list);
 829         mutex_unlock(&register_mutex);
 830
 831         if (timer->private_free)
 832                 timer->private_free(timer);
 833         kfree(timer);
 834         return 0;
 835 }
 836
 837 static int snd_timer_dev_free(struct snd_device *device)
 838 {
 839         struct snd_timer *timer = device->device_data;
 840         return snd_timer_free(timer);
 841 }
 842
 843 static int snd_timer_dev_register(struct snd_device *dev)
 844 {
 845         struct snd_timer *timer = dev->device_data;
 846         struct snd_timer *timer1;
 847         struct list_head *p;
 848
 849         snd_assert(timer != NULL && timer->hw.start != NULL &&
 850                    timer->hw.stop != NULL, return -ENXIO);
 851         if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
 852             !timer->hw.resolution && timer->hw.c_resolution == NULL)
 853                 return -EINVAL;
 854
 855         mutex_lock(&register_mutex);
 856         list_for_each(p, &snd_timer_list) {
 857                 timer1 = list_entry(p, struct snd_timer, device_list);
 858                 if (timer1->tmr_class > timer->tmr_class)
 859                         break;
 860                 if (timer1->tmr_class < timer->tmr_class)
 861                         continue;
 862                 if (timer1->card && timer->card) {
 863                         if (timer1->card->number > timer->card->number)
 864                                 break;
 865                         if (timer1->card->number < timer->card->number)
 866                                 continue;
 867                 }
 868                 if (timer1->tmr_device > timer->tmr_device)
 869                         break;
 870                 if (timer1->tmr_device < timer->tmr_device)
 871                         continue;
 872                 if (timer1->tmr_subdevice > timer->tmr_subdevice)
 873                         break;
 874                 if (timer1->tmr_subdevice < timer->tmr_subdevice)
 875                         continue;
 876                 /* conflicts.. */
 877                 mutex_unlock(&register_mutex);
 878                 return -EBUSY;
 879         }
 880         list_add_tail(&timer->device_list, p);
 881         mutex_unlock(&register_mutex);
 882         return 0;
 883 }
 884
 885 static int snd_timer_dev_disconnect(struct snd_device *device)
 886 {
 887         struct snd_timer *timer = device->device_data;
 888         mutex_lock(&register_mutex);
 889         list_del_init(&timer->device_list);
 890         mutex_unlock(&register_mutex);
 891         return 0;
 892 }
 893
 894 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
 895 {
 896         unsigned long flags;
 897         unsigned long resolution = 0;
 898         struct snd_timer_instance *ti, *ts;
 899         struct list_head *p, *n;
 900
 901         if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
 902                 return;
 903         snd_assert(event >= SNDRV_TIMER_EVENT_MSTART &&
 904                    event <= SNDRV_TIMER_EVENT_MRESUME, return);
 905         spin_lock_irqsave(&timer->lock, flags);
 906         if (event == SNDRV_TIMER_EVENT_MSTART ||
 907             event == SNDRV_TIMER_EVENT_MCONTINUE ||
 908             event == SNDRV_TIMER_EVENT_MRESUME) {
 909                 if (timer->hw.c_resolution)
 910                         resolution = timer->hw.c_resolution(timer);
 911                 else
 912                         resolution = timer->hw.resolution;
 913         }
 914         list_for_each(p, &timer->active_list_head) {
 915                 ti = list_entry(p, struct snd_timer_instance, active_list);
 916                 if (ti->ccallback)
 917                         ti->ccallback(ti, event, tstamp, resolution);
 918                 list_for_each(n, &ti->slave_active_head) {
 919                         ts = list_entry(n, struct snd_timer_instance, active_list);
 920                         if (ts->ccallback)
 921                                 ts->ccallback(ts, event, tstamp, resolution);
 922                 }
 923         }
 924         spin_unlock_irqrestore(&timer->lock, flags);
 925 }
 926
 927 /*
 928  * exported functions for global timers
 929  */
 930 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
 931 {
 932         struct snd_timer_id tid;
 933
 934         tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
 935         tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
 936         tid.card = -1;
 937         tid.device = device;
 938         tid.subdevice = 0;
 939         return snd_timer_new(NULL, id, &tid, rtimer);
 940 }
 941
 942 int snd_timer_global_free(struct snd_timer *timer)
 943 {
 944         return snd_timer_free(timer);
 945 }
 946
 947 int snd_timer_global_register(struct snd_timer *timer)
 948 {
 949         struct snd_device dev;
 950
 951         memset(&dev, 0, sizeof(dev));
 952         dev.device_data = timer;
 953         return snd_timer_dev_register(&dev);
 954 }
 955
 956 /*
 957  *  System timer
 958  */
 959
 960 struct snd_timer_system_private {
 961         struct timer_list tlist;
 962         unsigned long last_expires;
 963         unsigned long last_jiffies;
 964         unsigned long correction;
 965 };
 966
 967 static void snd_timer_s_function(unsigned long data)
 968 {
 969         struct snd_timer *timer = (struct snd_timer *)data;
 970         struct snd_timer_system_private *priv = timer->private_data;
 971         unsigned long jiff = jiffies;
 972         if (time_after(jiff, priv->last_expires))
 973                 priv->correction += (long)jiff - (long)priv->last_expires;
 974         snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
 975 }
 976
 977 static int snd_timer_s_start(struct snd_timer * timer)
 978 {
 979         struct snd_timer_system_private *priv;
 980         unsigned long njiff;
 981
 982         priv = (struct snd_timer_system_private *) timer->private_data;
 983         njiff = (priv->last_jiffies = jiffies);
 984         if (priv->correction > timer->sticks - 1) {
 985                 priv->correction -= timer->sticks - 1;
 986                 njiff++;
 987         } else {
 988                 njiff += timer->sticks - priv->correction;
 989                 priv->correction = 0;
 990         }
 991         priv->last_expires = priv->tlist.expires = njiff;
 992         add_timer(&priv->tlist);
 993         return 0;
 994 }
 995
 996 static int snd_timer_s_stop(struct snd_timer * timer)
 997 {
 998         struct snd_timer_system_private *priv;
 999         unsigned long jiff;
1000
1001         priv = (struct snd_timer_system_private *) timer->private_data;
1002         del_timer(&priv->tlist);
1003         jiff = jiffies;
1004         if (time_before(jiff, priv->last_expires))
1005                 timer->sticks = priv->last_expires - jiff;
1006         else
1007                 timer->sticks = 1;
1008         priv->correction = 0;
1009         return 0;
1010 }
1011
1012 static struct snd_timer_hardware snd_timer_system =
1013 {
1014         .flags =        SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
1015         .resolution =   1000000000L / HZ,
1016         .ticks =        10000000L,
1017         .start =        snd_timer_s_start,
1018         .stop =         snd_timer_s_stop
1019 };
1020
1021 static void snd_timer_free_system(struct snd_timer *timer)
1022 {
1023         kfree(timer->private_data);
1024 }
1025
1026 static int snd_timer_register_system(void)
1027 {
1028         struct snd_timer *timer;
1029         struct snd_timer_system_private *priv;
1030         int err;
1031
1032         err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1033         if (err < 0)
1034                 return err;
1035         strcpy(timer->name, "system timer");
1036         timer->hw = snd_timer_system;
1037         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1038         if (priv == NULL) {
1039                 snd_timer_free(timer);
1040                 return -ENOMEM;
1041         }
1042         init_timer(&priv->tlist);
1043         priv->tlist.function = snd_timer_s_function;
1044         priv->tlist.data = (unsigned long) timer;
1045         timer->private_data = priv;
1046         timer->private_free = snd_timer_free_system;
1047         return snd_timer_global_register(timer);
1048 }
1049
1050 #ifdef CONFIG_PROC_FS
1051 /*
1052  *  Info interface
1053  */
1054
1055 static void snd_timer_proc_read(struct snd_info_entry *entry,
1056                                 struct snd_info_buffer *buffer)
1057 {
1058         struct snd_timer *timer;
1059         struct snd_timer_instance *ti;
1060         struct list_head *p, *q;
1061
1062         mutex_lock(&register_mutex);
1063         list_for_each(p, &snd_timer_list) {
1064                 timer = list_entry(p, struct snd_timer, device_list);
1065                 switch (timer->tmr_class) {
1066                 case SNDRV_TIMER_CLASS_GLOBAL:
1067                         snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1068                         break;
1069                 case SNDRV_TIMER_CLASS_CARD:
1070                         snd_iprintf(buffer, "C%i-%i: ",
1071                                     timer->card->number, timer->tmr_device);
1072                         break;
1073                 case SNDRV_TIMER_CLASS_PCM:
1074                         snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1075                                     timer->tmr_device, timer->tmr_subdevice);
1076                         break;
1077                 default:
1078                         snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1079                                     timer->card ? timer->card->number : -1,
1080                                     timer->tmr_device, timer->tmr_subdevice);
1081                 }
1082                 snd_iprintf(buffer, "%s :", timer->name);
1083                 if (timer->hw.resolution)
1084                         snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1085                                     timer->hw.resolution / 1000,
1086                                     timer->hw.resolution % 1000,
1087                                     timer->hw.ticks);
1088                 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1089                         snd_iprintf(buffer, " SLAVE");
1090                 snd_iprintf(buffer, "\n");
1091                 list_for_each(q, &timer->open_list_head) {
1092                         ti = list_entry(q, struct snd_timer_instance, open_list);
1093                         snd_iprintf(buffer, "  Client %s : %s\n",
1094                                     ti->owner ? ti->owner : "unknown",
1095                                     ti->flags & (SNDRV_TIMER_IFLG_START |
1096                                                  SNDRV_TIMER_IFLG_RUNNING)
1097                                     ? "running" : "stopped");
1098                 }
1099         }
1100         mutex_unlock(&register_mutex);
1101 }
1102
1103 static struct snd_info_entry *snd_timer_proc_entry;
1104
1105 static void __init snd_timer_proc_init(void)
1106 {
1107         struct snd_info_entry *entry;
1108
1109         entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1110         if (entry != NULL) {
1111                 entry->c.text.read = snd_timer_proc_read;
1112                 if (snd_info_register(entry) < 0) {
1113                         snd_info_free_entry(entry);
1114                         entry = NULL;
1115                 }
1116         }
1117         snd_timer_proc_entry = entry;
1118 }
1119
1120 static void __exit snd_timer_proc_done(void)
1121 {
1122         snd_info_free_entry(snd_timer_proc_entry);
1123 }
1124 #else /* !CONFIG_PROC_FS */
1125 #define snd_timer_proc_init()
1126 #define snd_timer_proc_done()
1127 #endif
1128
1129 /*
1130  *  USER SPACE interface
1131  */
1132
1133 static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1134                                      unsigned long resolution,
1135                                      unsigned long ticks)
1136 {
1137         struct snd_timer_user *tu = timeri->callback_data;
1138         struct snd_timer_read *r;
1139         int prev;
1140
1141         spin_lock(&tu->qlock);
1142         if (tu->qused > 0) {
1143                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1144                 r = &tu->queue[prev];
1145                 if (r->resolution == resolution) {
1146                         r->ticks += ticks;
1147                         goto __wake;
1148                 }
1149         }
1150         if (tu->qused >= tu->queue_size) {
1151                 tu->overrun++;
1152         } else {
1153                 r = &tu->queue[tu->qtail++];
1154                 tu->qtail %= tu->queue_size;
1155                 r->resolution = resolution;
1156                 r->ticks = ticks;
1157                 tu->qused++;
1158         }
1159       __wake:
1160         spin_unlock(&tu->qlock);
1161         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1162         wake_up(&tu->qchange_sleep);
1163 }
1164
1165 static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1166                                             struct snd_timer_tread *tread)
1167 {
1168         if (tu->qused >= tu->queue_size) {
1169                 tu->overrun++;
1170         } else {
1171                 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1172                 tu->qtail %= tu->queue_size;
1173                 tu->qused++;
1174         }
1175 }
1176
1177 static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1178                                      int event,
1179                                      struct timespec *tstamp,
1180                                      unsigned long resolution)
1181 {
1182         struct snd_timer_user *tu = timeri->callback_data;
1183         struct snd_timer_tread r1;
1184
1185         if (event >= SNDRV_TIMER_EVENT_START &&
1186             event <= SNDRV_TIMER_EVENT_PAUSE)
1187                 tu->tstamp = *tstamp;
1188         if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1189                 return;
1190         r1.event = event;
1191         r1.tstamp = *tstamp;
1192         r1.val = resolution;
1193         spin_lock(&tu->qlock);
1194         snd_timer_user_append_to_tqueue(tu, &r1);
1195         spin_unlock(&tu->qlock);
1196         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1197         wake_up(&tu->qchange_sleep);
1198 }
1199
1200 static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1201                                       unsigned long resolution,
1202                                       unsigned long ticks)
1203 {
1204         struct snd_timer_user *tu = timeri->callback_data;
1205         struct snd_timer_tread *r, r1;
1206         struct timespec tstamp;
1207         int prev, append = 0;
1208
1209         memset(&tstamp, 0, sizeof(tstamp));
1210         spin_lock(&tu->qlock);
1211         if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1212                            (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1213                 spin_unlock(&tu->qlock);
1214                 return;
1215         }
1216         if (tu->last_resolution != resolution || ticks > 0)
1217                 getnstimeofday(&tstamp);
1218         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1219             tu->last_resolution != resolution) {
1220                 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1221                 r1.tstamp = tstamp;
1222                 r1.val = resolution;
1223                 snd_timer_user_append_to_tqueue(tu, &r1);
1224                 tu->last_resolution = resolution;
1225                 append++;
1226         }
1227         if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1228                 goto __wake;
1229         if (ticks == 0)
1230                 goto __wake;
1231         if (tu->qused > 0) {
1232                 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1233                 r = &tu->tqueue[prev];
1234                 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1235                         r->tstamp = tstamp;
1236                         r->val += ticks;
1237                         append++;
1238                         goto __wake;
1239                 }
1240         }
1241         r1.event = SNDRV_TIMER_EVENT_TICK;
1242         r1.tstamp = tstamp;
1243         r1.val = ticks;
1244         snd_timer_user_append_to_tqueue(tu, &r1);
1245         append++;
1246       __wake:
1247         spin_unlock(&tu->qlock);
1248         if (append == 0)
1249                 return;
1250         kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1251         wake_up(&tu->qchange_sleep);
1252 }
1253
1254 static int snd_timer_user_open(struct inode *inode, struct file *file)
1255 {
1256         struct snd_timer_user *tu;
1257
1258         tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1259         if (tu == NULL)
1260                 return -ENOMEM;
1261         spin_lock_init(&tu->qlock);
1262         init_waitqueue_head(&tu->qchange_sleep);
1263         mutex_init(&tu->tread_sem);
1264         tu->ticks = 1;
1265         tu->queue_size = 128;
1266         tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1267                             GFP_KERNEL);
1268         if (tu->queue == NULL) {
1269                 kfree(tu);
1270                 return -ENOMEM;
1271         }
1272         file->private_data = tu;
1273         return 0;
1274 }
1275
1276 static int snd_timer_user_release(struct inode *inode, struct file *file)
1277 {
1278         struct snd_timer_user *tu;
1279
1280         if (file->private_data) {
1281                 tu = file->private_data;
1282                 file->private_data = NULL;
1283                 fasync_helper(-1, file, 0, &tu->fasync);
1284                 if (tu->timeri)
1285                         snd_timer_close(tu->timeri);
1286                 kfree(tu->queue);
1287                 kfree(tu->tqueue);
1288                 kfree(tu);
1289         }
1290         return 0;
1291 }
1292
1293 static void snd_timer_user_zero_id(struct snd_timer_id *id)
1294 {
1295         id->dev_class = SNDRV_TIMER_CLASS_NONE;
1296         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1297         id->card = -1;
1298         id->device = -1;
1299         id->subdevice = -1;
1300 }
1301
1302 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1303 {
1304         id->dev_class = timer->tmr_class;
1305         id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1306         id->card = timer->card ? timer->card->number : -1;
1307         id->device = timer->tmr_device;
1308         id->subdevice = timer->tmr_subdevice;
1309 }
1310
1311 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1312 {
1313         struct snd_timer_id id;
1314         struct snd_timer *timer;
1315         struct list_head *p;
1316
1317         if (copy_from_user(&id, _tid, sizeof(id)))
1318                 return -EFAULT;
1319         mutex_lock(&register_mutex);
1320         if (id.dev_class < 0) {         /* first item */
1321                 if (list_empty(&snd_timer_list))
1322                         snd_timer_user_zero_id(&id);
1323                 else {
1324                         timer = list_entry(snd_timer_list.next,
1325                                            struct snd_timer, device_list);
1326                         snd_timer_user_copy_id(&id, timer);
1327                 }
1328         } else {
1329                 switch (id.dev_class) {
1330                 case SNDRV_TIMER_CLASS_GLOBAL:
1331                         id.device = id.device < 0 ? 0 : id.device + 1;
1332                         list_for_each(p, &snd_timer_list) {
1333                                 timer = list_entry(p, struct snd_timer, device_list);
1334                                 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1335                                         snd_timer_user_copy_id(&id, timer);
1336                                         break;
1337                                 }
1338                                 if (timer->tmr_device >= id.device) {
1339                                         snd_timer_user_copy_id(&id, timer);
1340                                         break;
1341                                 }
1342                         }
1343                         if (p == &snd_timer_list)
1344                                 snd_timer_user_zero_id(&id);
1345                         break;
1346                 case SNDRV_TIMER_CLASS_CARD:
1347                 case SNDRV_TIMER_CLASS_PCM:
1348                         if (id.card < 0) {
1349                                 id.card = 0;
1350                         } else {
1351                                 if (id.card < 0) {
1352                                         id.card = 0;
1353                                 } else {
1354                                         if (id.device < 0) {
1355                                                 id.device = 0;
1356                                         } else {
1357                                                 if (id.subdevice < 0) {
1358                                                         id.subdevice = 0;
1359                                                 } else {
1360                                                         id.subdevice++;
1361                                                 }
1362                                         }
1363                                 }
1364                         }
1365                         list_for_each(p, &snd_timer_list) {
1366                                 timer = list_entry(p, struct snd_timer, device_list);
1367                                 if (timer->tmr_class > id.dev_class) {
1368                                         snd_timer_user_copy_id(&id, timer);
1369                                         break;
1370                                 }
1371                                 if (timer->tmr_class < id.dev_class)
1372                                         continue;
1373                                 if (timer->card->number > id.card) {
1374                                         snd_timer_user_copy_id(&id, timer);
1375                                         break;
1376                                 }
1377                                 if (timer->card->number < id.card)
1378                                         continue;
1379                                 if (timer->tmr_device > id.device) {
1380                                         snd_timer_user_copy_id(&id, timer);
1381                                         break;
1382                                 }
1383                                 if (timer->tmr_device < id.device)
1384                                         continue;
1385                                 if (timer->tmr_subdevice > id.subdevice) {
1386                                         snd_timer_user_copy_id(&id, timer);
1387                                         break;
1388                                 }
1389                                 if (timer->tmr_subdevice < id.subdevice)
1390                                         continue;
1391                                 snd_timer_user_copy_id(&id, timer);
1392                                 break;
1393                         }
1394                         if (p == &snd_timer_list)
1395                                 snd_timer_user_zero_id(&id);
1396                         break;
1397                 default:
1398                         snd_timer_user_zero_id(&id);
1399                 }
1400         }
1401         mutex_unlock(&register_mutex);
1402         if (copy_to_user(_tid, &id, sizeof(*_tid)))
1403                 return -EFAULT;
1404         return 0;
1405 }
1406
1407 static int snd_timer_user_ginfo(struct file *file,
1408                                 struct snd_timer_ginfo __user *_ginfo)
1409 {
1410         struct snd_timer_ginfo *ginfo;
1411         struct snd_timer_id tid;
1412         struct snd_timer *t;
1413         struct list_head *p;
1414         int err = 0;
1415
1416         ginfo = kmalloc(sizeof(*ginfo), GFP_KERNEL);
1417         if (! ginfo)
1418                 return -ENOMEM;
1419         if (copy_from_user(ginfo, _ginfo, sizeof(*ginfo))) {
1420                 kfree(ginfo);
1421                 return -EFAULT;
1422         }
1423         tid = ginfo->tid;
1424         memset(ginfo, 0, sizeof(*ginfo));
1425         ginfo->tid = tid;
1426         mutex_lock(&register_mutex);
1427         t = snd_timer_find(&tid);
1428         if (t != NULL) {
1429                 ginfo->card = t->card ? t->card->number : -1;
1430                 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1431                         ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1432                 strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1433                 strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1434                 ginfo->resolution = t->hw.resolution;
1435                 if (t->hw.resolution_min > 0) {
1436                         ginfo->resolution_min = t->hw.resolution_min;
1437                         ginfo->resolution_max = t->hw.resolution_max;
1438                 }
1439                 list_for_each(p, &t->open_list_head) {
1440                         ginfo->clients++;
1441                 }
1442         } else {
1443                 err = -ENODEV;
1444         }
1445         mutex_unlock(&register_mutex);
1446         if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1447                 err = -EFAULT;
1448         kfree(ginfo);
1449         return err;
1450 }
1451
1452 static int snd_timer_user_gparams(struct file *file,
1453                                   struct snd_timer_gparams __user *_gparams)
1454 {
1455         struct snd_timer_gparams gparams;
1456         struct snd_timer *t;
1457         int err;
1458
1459         if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1460                 return -EFAULT;
1461         mutex_lock(&register_mutex);
1462         t = snd_timer_find(&gparams.tid);
1463         if (!t) {
1464                 err = -ENODEV;
1465                 goto _error;
1466         }
1467         if (!list_empty(&t->open_list_head)) {
1468                 err = -EBUSY;
1469                 goto _error;
1470         }
1471         if (!t->hw.set_period) {
1472                 err = -ENOSYS;
1473                 goto _error;
1474         }
1475         err = t->hw.set_period(t, gparams.period_num, gparams.period_den);
1476 _error:
1477         mutex_unlock(&register_mutex);
1478         return err;
1479 }
1480
1481 static int snd_timer_user_gstatus(struct file *file,
1482                                   struct snd_timer_gstatus __user *_gstatus)
1483 {
1484         struct snd_timer_gstatus gstatus;
1485         struct snd_timer_id tid;
1486         struct snd_timer *t;
1487         int err = 0;
1488
1489         if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1490                 return -EFAULT;
1491         tid = gstatus.tid;
1492         memset(&gstatus, 0, sizeof(gstatus));
1493         gstatus.tid = tid;
1494         mutex_lock(&register_mutex);
1495         t = snd_timer_find(&tid);
1496         if (t != NULL) {
1497                 if (t->hw.c_resolution)
1498                         gstatus.resolution = t->hw.c_resolution(t);
1499                 else
1500                         gstatus.resolution = t->hw.resolution;
1501                 if (t->hw.precise_resolution) {
1502                         t->hw.precise_resolution(t, &gstatus.resolution_num,
1503                                                  &gstatus.resolution_den);
1504                 } else {
1505                         gstatus.resolution_num = gstatus.resolution;
1506                         gstatus.resolution_den = 1000000000uL;
1507                 }
1508         } else {
1509                 err = -ENODEV;
1510         }
1511         mutex_unlock(&register_mutex);
1512         if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1513                 err = -EFAULT;
1514         return err;
1515 }
1516
1517 static int snd_timer_user_tselect(struct file *file,
1518                                   struct snd_timer_select __user *_tselect)
1519 {
1520         struct snd_timer_user *tu;
1521         struct snd_timer_select tselect;
1522         char str[32];
1523         int err = 0;
1524
1525         tu = file->private_data;
1526         mutex_lock(&tu->tread_sem);
1527         if (tu->timeri) {
1528                 snd_timer_close(tu->timeri);
1529                 tu->timeri = NULL;
1530         }
1531         if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1532                 err = -EFAULT;
1533                 goto __err;
1534         }
1535         sprintf(str, "application %i", current->pid);
1536         if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1537                 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1538         err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1539         if (err < 0)
1540                 goto __err;
1541
1542         kfree(tu->queue);
1543         tu->queue = NULL;
1544         kfree(tu->tqueue);
1545         tu->tqueue = NULL;
1546         if (tu->tread) {
1547                 tu->tqueue = kmalloc(tu->queue_size * sizeof(struct snd_timer_tread),
1548                                      GFP_KERNEL);
1549                 if (tu->tqueue == NULL)
1550                         err = -ENOMEM;
1551         } else {
1552                 tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
1553                                     GFP_KERNEL);
1554                 if (tu->queue == NULL)
1555                         err = -ENOMEM;
1556         }
1557
1558         if (err < 0) {
1559                 snd_timer_close(tu->timeri);
1560                 tu->timeri = NULL;
1561         } else {
1562                 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1563                 tu->timeri->callback = tu->tread
1564                         ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1565                 tu->timeri->ccallback = snd_timer_user_ccallback;
1566                 tu->timeri->callback_data = (void *)tu;
1567         }
1568
1569       __err:
1570         mutex_unlock(&tu->tread_sem);
1571         return err;
1572 }
1573
1574 static int snd_timer_user_info(struct file *file,
1575                                struct snd_timer_info __user *_info)
1576 {
1577         struct snd_timer_user *tu;
1578         struct snd_timer_info *info;
1579         struct snd_timer *t;
1580         int err = 0;
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
1587         info = kzalloc(sizeof(*info), GFP_KERNEL);
1588         if (! info)
1589                 return -ENOMEM;
1590         info->card = t->card ? t->card->number : -1;
1591         if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1592                 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1593         strlcpy(info->id, t->id, sizeof(info->id));
1594         strlcpy(info->name, t->name, sizeof(info->name));
1595         info->resolution = t->hw.resolution;
1596         if (copy_to_user(_info, info, sizeof(*_info)))
1597                 err = -EFAULT;
1598         kfree(info);
1599         return err;
1600 }
1601
1602 static int snd_timer_user_params(struct file *file,
1603                                  struct snd_timer_params __user *_params)
1604 {
1605         struct snd_timer_user *tu;
1606         struct snd_timer_params params;
1607         struct snd_timer *t;
1608         struct snd_timer_read *tr;
1609         struct snd_timer_tread *ttr;
1610         int err;
1611
1612         tu = file->private_data;
1613         snd_assert(tu->timeri != NULL, return -ENXIO);
1614         t = tu->timeri->timer;
1615         snd_assert(t != NULL, return -ENXIO);
1616         if (copy_from_user(&params, _params, sizeof(params)))
1617                 return -EFAULT;
1618         if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE) && params.ticks < 1) {
1619                 err = -EINVAL;
1620                 goto _end;
1621         }
1622         if (params.queue_size > 0 &&
1623             (params.queue_size < 32 || params.queue_size > 1024)) {
1624                 err = -EINVAL;
1625                 goto _end;
1626         }
1627         if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1628                               (1<<SNDRV_TIMER_EVENT_TICK)|
1629                               (1<<SNDRV_TIMER_EVENT_START)|
1630                               (1<<SNDRV_TIMER_EVENT_STOP)|
1631                               (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1632                               (1<<SNDRV_TIMER_EVENT_PAUSE)|
1633                               (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1634                               (1<<SNDRV_TIMER_EVENT_RESUME)|
1635                               (1<<SNDRV_TIMER_EVENT_MSTART)|
1636                               (1<<SNDRV_TIMER_EVENT_MSTOP)|
1637                               (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1638                               (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1639                               (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1640                               (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1641                 err = -EINVAL;
1642                 goto _end;
1643         }
1644         snd_timer_stop(tu->timeri);
1645         spin_lock_irq(&t->lock);
1646         tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1647                                SNDRV_TIMER_IFLG_EXCLUSIVE|
1648                                SNDRV_TIMER_IFLG_EARLY_EVENT);
1649         if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1650                 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1651         if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1652                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1653         if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1654                 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1655         spin_unlock_irq(&t->lock);
1656         if (params.queue_size > 0 &&
1657             (unsigned int)tu->queue_size != params.queue_size) {
1658                 if (tu->tread) {
1659                         ttr = kmalloc(params.queue_size * sizeof(*ttr),
1660                                       GFP_KERNEL);
1661                         if (ttr) {
1662                                 kfree(tu->tqueue);
1663                                 tu->queue_size = params.queue_size;
1664                                 tu->tqueue = ttr;
1665                         }
1666                 } else {
1667                         tr = kmalloc(params.queue_size * sizeof(*tr),
1668                                      GFP_KERNEL);
1669                         if (tr) {
1670                                 kfree(tu->queue);
1671                                 tu->queue_size = params.queue_size;
1672                                 tu->queue = tr;
1673                         }
1674                 }
1675         }
1676         tu->qhead = tu->qtail = tu->qused = 0;
1677         if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1678                 if (tu->tread) {
1679                         struct snd_timer_tread tread;
1680                         tread.event = SNDRV_TIMER_EVENT_EARLY;
1681                         tread.tstamp.tv_sec = 0;
1682                         tread.tstamp.tv_nsec = 0;
1683                         tread.val = 0;
1684                         snd_timer_user_append_to_tqueue(tu, &tread);
1685                 } else {
1686                         struct snd_timer_read *r = &tu->queue[0];
1687                         r->resolution = 0;
1688                         r->ticks = 0;
1689                         tu->qused++;
1690                         tu->qtail++;
1691                 }
1692         }
1693         tu->filter = params.filter;
1694         tu->ticks = params.ticks;
1695         err = 0;
1696  _end:
1697         if (copy_to_user(_params, &params, sizeof(params)))
1698                 return -EFAULT;
1699         return err;
1700 }
1701
1702 static int snd_timer_user_status(struct file *file,
1703                                  struct snd_timer_status __user *_status)
1704 {
1705         struct snd_timer_user *tu;
1706         struct snd_timer_status status;
1707
1708         tu = file->private_data;
1709         snd_assert(tu->timeri != NULL, return -ENXIO);
1710         memset(&status, 0, sizeof(status));
1711         status.tstamp = tu->tstamp;
1712         status.resolution = snd_timer_resolution(tu->timeri);
1713         status.lost = tu->timeri->lost;
1714         status.overrun = tu->overrun;
1715         spin_lock_irq(&tu->qlock);
1716         status.queue = tu->qused;
1717         spin_unlock_irq(&tu->qlock);
1718         if (copy_to_user(_status, &status, sizeof(status)))
1719                 return -EFAULT;
1720         return 0;
1721 }
1722
1723 static int snd_timer_user_start(struct file *file)
1724 {
1725         int err;
1726         struct snd_timer_user *tu;
1727
1728         tu = file->private_data;
1729         snd_assert(tu->timeri != NULL, return -ENXIO);
1730         snd_timer_stop(tu->timeri);
1731         tu->timeri->lost = 0;
1732         tu->last_resolution = 0;
1733         return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0;
1734 }
1735
1736 static int snd_timer_user_stop(struct file *file)
1737 {
1738         int err;
1739         struct snd_timer_user *tu;
1740
1741         tu = file->private_data;
1742         snd_assert(tu->timeri != NULL, return -ENXIO);
1743         return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0;
1744 }
1745
1746 static int snd_timer_user_continue(struct file *file)
1747 {
1748         int err;
1749         struct snd_timer_user *tu;
1750
1751         tu = file->private_data;
1752         snd_assert(tu->timeri != NULL, return -ENXIO);
1753         tu->timeri->lost = 0;
1754         return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0;
1755 }
1756
1757 static int snd_timer_user_pause(struct file *file)
1758 {
1759         int err;
1760         struct snd_timer_user *tu;
1761
1762         tu = file->private_data;
1763         snd_assert(tu->timeri != NULL, return -ENXIO);
1764         return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0;
1765 }
1766
1767 enum {
1768         SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1769         SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1770         SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1771         SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1772 };
1773
1774 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1775                                  unsigned long arg)
1776 {
1777         struct snd_timer_user *tu;
1778         void __user *argp = (void __user *)arg;
1779         int __user *p = argp;
1780
1781         tu = file->private_data;
1782         switch (cmd) {
1783         case SNDRV_TIMER_IOCTL_PVERSION:
1784                 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1785         case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1786                 return snd_timer_user_next_device(argp);
1787         case SNDRV_TIMER_IOCTL_TREAD:
1788         {
1789                 int xarg;
1790
1791                 mutex_lock(&tu->tread_sem);
1792                 if (tu->timeri) {       /* too late */
1793                         mutex_unlock(&tu->tread_sem);
1794                         return -EBUSY;
1795                 }
1796                 if (get_user(xarg, p)) {
1797                         mutex_unlock(&tu->tread_sem);
1798                         return -EFAULT;
1799                 }
1800                 tu->tread = xarg ? 1 : 0;
1801                 mutex_unlock(&tu->tread_sem);
1802                 return 0;
1803         }
1804         case SNDRV_TIMER_IOCTL_GINFO:
1805                 return snd_timer_user_ginfo(file, argp);
1806         case SNDRV_TIMER_IOCTL_GPARAMS:
1807                 return snd_timer_user_gparams(file, argp);
1808         case SNDRV_TIMER_IOCTL_GSTATUS:
1809                 return snd_timer_user_gstatus(file, argp);
1810         case SNDRV_TIMER_IOCTL_SELECT:
1811                 return snd_timer_user_tselect(file, argp);
1812         case SNDRV_TIMER_IOCTL_INFO:
1813                 return snd_timer_user_info(file, argp);
1814         case SNDRV_TIMER_IOCTL_PARAMS:
1815                 return snd_timer_user_params(file, argp);
1816         case SNDRV_TIMER_IOCTL_STATUS:
1817                 return snd_timer_user_status(file, argp);
1818         case SNDRV_TIMER_IOCTL_START:
1819         case SNDRV_TIMER_IOCTL_START_OLD:
1820                 return snd_timer_user_start(file);
1821         case SNDRV_TIMER_IOCTL_STOP:
1822         case SNDRV_TIMER_IOCTL_STOP_OLD:
1823                 return snd_timer_user_stop(file);
1824         case SNDRV_TIMER_IOCTL_CONTINUE:
1825         case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
1826                 return snd_timer_user_continue(file);
1827         case SNDRV_TIMER_IOCTL_PAUSE:
1828         case SNDRV_TIMER_IOCTL_PAUSE_OLD:
1829                 return snd_timer_user_pause(file);
1830         }
1831         return -ENOTTY;
1832 }
1833
1834 static int snd_timer_user_fasync(int fd, struct file * file, int on)
1835 {
1836         struct snd_timer_user *tu;
1837         int err;
1838
1839         tu = file->private_data;
1840         err = fasync_helper(fd, file, on, &tu->fasync);
1841         if (err < 0)
1842                 return err;
1843         return 0;
1844 }
1845
1846 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
1847                                    size_t count, loff_t *offset)
1848 {
1849         struct snd_timer_user *tu;
1850         long result = 0, unit;
1851         int err = 0;
1852
1853         tu = file->private_data;
1854         unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
1855         spin_lock_irq(&tu->qlock);
1856         while ((long)count - result >= unit) {
1857                 while (!tu->qused) {
1858                         wait_queue_t wait;
1859
1860                         if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
1861                                 err = -EAGAIN;
1862                                 break;
1863                         }
1864
1865                         set_current_state(TASK_INTERRUPTIBLE);
1866                         init_waitqueue_entry(&wait, current);
1867                         add_wait_queue(&tu->qchange_sleep, &wait);
1868
1869                         spin_unlock_irq(&tu->qlock);
1870                         schedule();
1871                         spin_lock_irq(&tu->qlock);
1872
1873                         remove_wait_queue(&tu->qchange_sleep, &wait);
1874
1875                         if (signal_pending(current)) {
1876                                 err = -ERESTARTSYS;
1877                                 break;
1878                         }
1879                 }
1880
1881                 spin_unlock_irq(&tu->qlock);
1882                 if (err < 0)
1883                         goto _error;
1884
1885                 if (tu->tread) {
1886                         if (copy_to_user(buffer, &tu->tqueue[tu->qhead++],
1887                                          sizeof(struct snd_timer_tread))) {
1888                                 err = -EFAULT;
1889                                 goto _error;
1890                         }
1891                 } else {
1892                         if (copy_to_user(buffer, &tu->queue[tu->qhead++],
1893                                          sizeof(struct snd_timer_read))) {
1894                                 err = -EFAULT;
1895                                 goto _error;
1896                         }
1897                 }
1898
1899                 tu->qhead %= tu->queue_size;
1900
1901                 result += unit;
1902                 buffer += unit;
1903
1904                 spin_lock_irq(&tu->qlock);
1905                 tu->qused--;
1906         }
1907         spin_unlock_irq(&tu->qlock);
1908  _error:
1909         return result > 0 ? result : err;
1910 }
1911
1912 static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
1913 {
1914         unsigned int mask;
1915         struct snd_timer_user *tu;
1916
1917         tu = file->private_data;
1918
1919         poll_wait(file, &tu->qchange_sleep, wait);
1920
1921         mask = 0;
1922         if (tu->qused)
1923                 mask |= POLLIN | POLLRDNORM;
1924
1925         return mask;
1926 }
1927
1928 #ifdef CONFIG_COMPAT
1929 #include "timer_compat.c"
1930 #else
1931 #define snd_timer_user_ioctl_compat     NULL
1932 #endif
1933
1934 static struct file_operations snd_timer_f_ops =
1935 {
1936         .owner =        THIS_MODULE,
1937         .read =         snd_timer_user_read,
1938         .open =         snd_timer_user_open,
1939         .release =      snd_timer_user_release,
1940         .poll =         snd_timer_user_poll,
1941         .unlocked_ioctl =       snd_timer_user_ioctl,
1942         .compat_ioctl = snd_timer_user_ioctl_compat,
1943         .fasync =       snd_timer_user_fasync,
1944 };
1945
1946 /*
1947  *  ENTRY functions
1948  */
1949
1950 static int __init alsa_timer_init(void)
1951 {
1952         int err;
1953
1954 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
1955         snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
1956                               "system timer");
1957 #endif
1958
1959         if ((err = snd_timer_register_system()) < 0)
1960                 snd_printk(KERN_ERR "unable to register system timer (%i)\n",
1961                            err);
1962         if ((err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
1963                                        &snd_timer_f_ops, NULL, "timer")) < 0)
1964                 snd_printk(KERN_ERR "unable to register timer device (%i)\n",
1965                            err);
1966         snd_timer_proc_init();
1967         return 0;
1968 }
1969
1970 static void __exit alsa_timer_exit(void)
1971 {
1972         struct list_head *p, *n;
1973
1974         snd_unregister_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0);
1975         /* unregister the system timer */
1976         list_for_each_safe(p, n, &snd_timer_list) {
1977                 struct snd_timer *timer = list_entry(p, struct snd_timer, device_list);
1978                 snd_timer_free(timer);
1979         }
1980         snd_timer_proc_done();
1981 #ifdef SNDRV_OSS_INFO_DEV_TIMERS
1982         snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
1983 #endif
1984 }
1985
1986 module_init(alsa_timer_init)
1987 module_exit(alsa_timer_exit)
1988
1989 EXPORT_SYMBOL(snd_timer_open);
1990 EXPORT_SYMBOL(snd_timer_close);
1991 EXPORT_SYMBOL(snd_timer_resolution);
1992 EXPORT_SYMBOL(snd_timer_start);
1993 EXPORT_SYMBOL(snd_timer_stop);
1994 EXPORT_SYMBOL(snd_timer_continue);
1995 EXPORT_SYMBOL(snd_timer_pause);
1996 EXPORT_SYMBOL(snd_timer_new);
1997 EXPORT_SYMBOL(snd_timer_notify);
1998 EXPORT_SYMBOL(snd_timer_global_new);
1999 EXPORT_SYMBOL(snd_timer_global_free);
2000 EXPORT_SYMBOL(snd_timer_global_register);
2001 EXPORT_SYMBOL(snd_timer_interrupt);