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/device.h> 28 #include <linux/module.h> 29 #include <linux/string.h> 30 #include <linux/sched/signal.h> 31 #include <sound/core.h> 32 #include <sound/timer.h> 33 #include <sound/control.h> 34 #include <sound/info.h> 35 #include <sound/minors.h> 36 #include <sound/initval.h> 37 #include <linux/kmod.h> 38 39 /* internal flags */ 40 #define SNDRV_TIMER_IFLG_PAUSED 0x00010000 41 42 #if IS_ENABLED(CONFIG_SND_HRTIMER) 43 #define DEFAULT_TIMER_LIMIT 4 44 #else 45 #define DEFAULT_TIMER_LIMIT 1 46 #endif 47 48 static int timer_limit = DEFAULT_TIMER_LIMIT; 49 static int timer_tstamp_monotonic = 1; 50 MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>"); 51 MODULE_DESCRIPTION("ALSA timer interface"); 52 MODULE_LICENSE("GPL"); 53 module_param(timer_limit, int, 0444); 54 MODULE_PARM_DESC(timer_limit, "Maximum global timers in system."); 55 module_param(timer_tstamp_monotonic, int, 0444); 56 MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default)."); 57 58 MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER); 59 MODULE_ALIAS("devname:snd/timer"); 60 61 struct snd_timer_user { 62 struct snd_timer_instance *timeri; 63 int tread; /* enhanced read with timestamps and events */ 64 unsigned long ticks; 65 unsigned long overrun; 66 int qhead; 67 int qtail; 68 int qused; 69 int queue_size; 70 bool disconnected; 71 struct snd_timer_read *queue; 72 struct snd_timer_tread *tqueue; 73 spinlock_t qlock; 74 unsigned long last_resolution; 75 unsigned int filter; 76 struct timespec tstamp; /* trigger tstamp */ 77 wait_queue_head_t qchange_sleep; 78 struct fasync_struct *fasync; 79 struct mutex ioctl_lock; 80 }; 81 82 /* list of timers */ 83 static LIST_HEAD(snd_timer_list); 84 85 /* list of slave instances */ 86 static LIST_HEAD(snd_timer_slave_list); 87 88 /* lock for slave active lists */ 89 static DEFINE_SPINLOCK(slave_active_lock); 90 91 static DEFINE_MUTEX(register_mutex); 92 93 static int snd_timer_free(struct snd_timer *timer); 94 static int snd_timer_dev_free(struct snd_device *device); 95 static int snd_timer_dev_register(struct snd_device *device); 96 static int snd_timer_dev_disconnect(struct snd_device *device); 97 98 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left); 99 100 /* 101 * create a timer instance with the given owner string. 102 * when timer is not NULL, increments the module counter 103 */ 104 static struct snd_timer_instance *snd_timer_instance_new(char *owner, 105 struct snd_timer *timer) 106 { 107 struct snd_timer_instance *timeri; 108 timeri = kzalloc(sizeof(*timeri), GFP_KERNEL); 109 if (timeri == NULL) 110 return NULL; 111 timeri->owner = kstrdup(owner, GFP_KERNEL); 112 if (! timeri->owner) { 113 kfree(timeri); 114 return NULL; 115 } 116 INIT_LIST_HEAD(&timeri->open_list); 117 INIT_LIST_HEAD(&timeri->active_list); 118 INIT_LIST_HEAD(&timeri->ack_list); 119 INIT_LIST_HEAD(&timeri->slave_list_head); 120 INIT_LIST_HEAD(&timeri->slave_active_head); 121 122 timeri->timer = timer; 123 if (timer && !try_module_get(timer->module)) { 124 kfree(timeri->owner); 125 kfree(timeri); 126 return NULL; 127 } 128 129 return timeri; 130 } 131 132 /* 133 * find a timer instance from the given timer id 134 */ 135 static struct snd_timer *snd_timer_find(struct snd_timer_id *tid) 136 { 137 struct snd_timer *timer = NULL; 138 139 list_for_each_entry(timer, &snd_timer_list, device_list) { 140 if (timer->tmr_class != tid->dev_class) 141 continue; 142 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD || 143 timer->tmr_class == SNDRV_TIMER_CLASS_PCM) && 144 (timer->card == NULL || 145 timer->card->number != tid->card)) 146 continue; 147 if (timer->tmr_device != tid->device) 148 continue; 149 if (timer->tmr_subdevice != tid->subdevice) 150 continue; 151 return timer; 152 } 153 return NULL; 154 } 155 156 #ifdef CONFIG_MODULES 157 158 static void snd_timer_request(struct snd_timer_id *tid) 159 { 160 switch (tid->dev_class) { 161 case SNDRV_TIMER_CLASS_GLOBAL: 162 if (tid->device < timer_limit) 163 request_module("snd-timer-%i", tid->device); 164 break; 165 case SNDRV_TIMER_CLASS_CARD: 166 case SNDRV_TIMER_CLASS_PCM: 167 if (tid->card < snd_ecards_limit) 168 request_module("snd-card-%i", tid->card); 169 break; 170 default: 171 break; 172 } 173 } 174 175 #endif 176 177 /* 178 * look for a master instance matching with the slave id of the given slave. 179 * when found, relink the open_link of the slave. 180 * 181 * call this with register_mutex down. 182 */ 183 static void snd_timer_check_slave(struct snd_timer_instance *slave) 184 { 185 struct snd_timer *timer; 186 struct snd_timer_instance *master; 187 188 /* FIXME: it's really dumb to look up all entries.. */ 189 list_for_each_entry(timer, &snd_timer_list, device_list) { 190 list_for_each_entry(master, &timer->open_list_head, open_list) { 191 if (slave->slave_class == master->slave_class && 192 slave->slave_id == master->slave_id) { 193 list_move_tail(&slave->open_list, 194 &master->slave_list_head); 195 spin_lock_irq(&slave_active_lock); 196 slave->master = master; 197 slave->timer = master->timer; 198 spin_unlock_irq(&slave_active_lock); 199 return; 200 } 201 } 202 } 203 } 204 205 /* 206 * look for slave instances matching with the slave id of the given master. 207 * when found, relink the open_link of slaves. 208 * 209 * call this with register_mutex down. 210 */ 211 static void snd_timer_check_master(struct snd_timer_instance *master) 212 { 213 struct snd_timer_instance *slave, *tmp; 214 215 /* check all pending slaves */ 216 list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) { 217 if (slave->slave_class == master->slave_class && 218 slave->slave_id == master->slave_id) { 219 list_move_tail(&slave->open_list, &master->slave_list_head); 220 spin_lock_irq(&slave_active_lock); 221 spin_lock(&master->timer->lock); 222 slave->master = master; 223 slave->timer = master->timer; 224 if (slave->flags & SNDRV_TIMER_IFLG_RUNNING) 225 list_add_tail(&slave->active_list, 226 &master->slave_active_head); 227 spin_unlock(&master->timer->lock); 228 spin_unlock_irq(&slave_active_lock); 229 } 230 } 231 } 232 233 /* 234 * open a timer instance 235 * when opening a master, the slave id must be here given. 236 */ 237 int snd_timer_open(struct snd_timer_instance **ti, 238 char *owner, struct snd_timer_id *tid, 239 unsigned int slave_id) 240 { 241 struct snd_timer *timer; 242 struct snd_timer_instance *timeri = NULL; 243 244 if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) { 245 /* open a slave instance */ 246 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE || 247 tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) { 248 pr_debug("ALSA: timer: invalid slave class %i\n", 249 tid->dev_sclass); 250 return -EINVAL; 251 } 252 mutex_lock(®ister_mutex); 253 timeri = snd_timer_instance_new(owner, NULL); 254 if (!timeri) { 255 mutex_unlock(®ister_mutex); 256 return -ENOMEM; 257 } 258 timeri->slave_class = tid->dev_sclass; 259 timeri->slave_id = tid->device; 260 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE; 261 list_add_tail(&timeri->open_list, &snd_timer_slave_list); 262 snd_timer_check_slave(timeri); 263 mutex_unlock(®ister_mutex); 264 *ti = timeri; 265 return 0; 266 } 267 268 /* open a master instance */ 269 mutex_lock(®ister_mutex); 270 timer = snd_timer_find(tid); 271 #ifdef CONFIG_MODULES 272 if (!timer) { 273 mutex_unlock(®ister_mutex); 274 snd_timer_request(tid); 275 mutex_lock(®ister_mutex); 276 timer = snd_timer_find(tid); 277 } 278 #endif 279 if (!timer) { 280 mutex_unlock(®ister_mutex); 281 return -ENODEV; 282 } 283 if (!list_empty(&timer->open_list_head)) { 284 timeri = list_entry(timer->open_list_head.next, 285 struct snd_timer_instance, open_list); 286 if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) { 287 mutex_unlock(®ister_mutex); 288 return -EBUSY; 289 } 290 } 291 timeri = snd_timer_instance_new(owner, timer); 292 if (!timeri) { 293 mutex_unlock(®ister_mutex); 294 return -ENOMEM; 295 } 296 /* take a card refcount for safe disconnection */ 297 if (timer->card) 298 get_device(&timer->card->card_dev); 299 timeri->slave_class = tid->dev_sclass; 300 timeri->slave_id = slave_id; 301 302 if (list_empty(&timer->open_list_head) && timer->hw.open) { 303 int err = timer->hw.open(timer); 304 if (err) { 305 kfree(timeri->owner); 306 kfree(timeri); 307 308 if (timer->card) 309 put_device(&timer->card->card_dev); 310 module_put(timer->module); 311 mutex_unlock(®ister_mutex); 312 return err; 313 } 314 } 315 316 list_add_tail(&timeri->open_list, &timer->open_list_head); 317 snd_timer_check_master(timeri); 318 mutex_unlock(®ister_mutex); 319 *ti = timeri; 320 return 0; 321 } 322 EXPORT_SYMBOL(snd_timer_open); 323 324 /* 325 * close a timer instance 326 */ 327 int snd_timer_close(struct snd_timer_instance *timeri) 328 { 329 struct snd_timer *timer = NULL; 330 struct snd_timer_instance *slave, *tmp; 331 332 if (snd_BUG_ON(!timeri)) 333 return -ENXIO; 334 335 mutex_lock(®ister_mutex); 336 list_del(&timeri->open_list); 337 338 /* force to stop the timer */ 339 snd_timer_stop(timeri); 340 341 timer = timeri->timer; 342 if (timer) { 343 /* wait, until the active callback is finished */ 344 spin_lock_irq(&timer->lock); 345 while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) { 346 spin_unlock_irq(&timer->lock); 347 udelay(10); 348 spin_lock_irq(&timer->lock); 349 } 350 spin_unlock_irq(&timer->lock); 351 352 /* remove slave links */ 353 spin_lock_irq(&slave_active_lock); 354 spin_lock(&timer->lock); 355 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head, 356 open_list) { 357 list_move_tail(&slave->open_list, &snd_timer_slave_list); 358 slave->master = NULL; 359 slave->timer = NULL; 360 list_del_init(&slave->ack_list); 361 list_del_init(&slave->active_list); 362 } 363 spin_unlock(&timer->lock); 364 spin_unlock_irq(&slave_active_lock); 365 366 /* slave doesn't need to release timer resources below */ 367 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) 368 timer = NULL; 369 } 370 371 if (timeri->private_free) 372 timeri->private_free(timeri); 373 kfree(timeri->owner); 374 kfree(timeri); 375 376 if (timer) { 377 if (list_empty(&timer->open_list_head) && timer->hw.close) 378 timer->hw.close(timer); 379 /* release a card refcount for safe disconnection */ 380 if (timer->card) 381 put_device(&timer->card->card_dev); 382 module_put(timer->module); 383 } 384 385 mutex_unlock(®ister_mutex); 386 return 0; 387 } 388 EXPORT_SYMBOL(snd_timer_close); 389 390 unsigned long snd_timer_resolution(struct snd_timer_instance *timeri) 391 { 392 struct snd_timer * timer; 393 394 if (timeri == NULL) 395 return 0; 396 timer = timeri->timer; 397 if (timer) { 398 if (timer->hw.c_resolution) 399 return timer->hw.c_resolution(timer); 400 return timer->hw.resolution; 401 } 402 return 0; 403 } 404 EXPORT_SYMBOL(snd_timer_resolution); 405 406 static void snd_timer_notify1(struct snd_timer_instance *ti, int event) 407 { 408 struct snd_timer *timer; 409 unsigned long resolution = 0; 410 struct snd_timer_instance *ts; 411 struct timespec tstamp; 412 413 if (timer_tstamp_monotonic) 414 ktime_get_ts(&tstamp); 415 else 416 getnstimeofday(&tstamp); 417 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START || 418 event > SNDRV_TIMER_EVENT_PAUSE)) 419 return; 420 if (event == SNDRV_TIMER_EVENT_START || 421 event == SNDRV_TIMER_EVENT_CONTINUE) 422 resolution = snd_timer_resolution(ti); 423 if (ti->ccallback) 424 ti->ccallback(ti, event, &tstamp, resolution); 425 if (ti->flags & SNDRV_TIMER_IFLG_SLAVE) 426 return; 427 timer = ti->timer; 428 if (timer == NULL) 429 return; 430 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE) 431 return; 432 list_for_each_entry(ts, &ti->slave_active_head, active_list) 433 if (ts->ccallback) 434 ts->ccallback(ts, event + 100, &tstamp, resolution); 435 } 436 437 /* start/continue a master timer */ 438 static int snd_timer_start1(struct snd_timer_instance *timeri, 439 bool start, unsigned long ticks) 440 { 441 struct snd_timer *timer; 442 int result; 443 unsigned long flags; 444 445 timer = timeri->timer; 446 if (!timer) 447 return -EINVAL; 448 449 spin_lock_irqsave(&timer->lock, flags); 450 if (timer->card && timer->card->shutdown) { 451 result = -ENODEV; 452 goto unlock; 453 } 454 if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING | 455 SNDRV_TIMER_IFLG_START)) { 456 result = -EBUSY; 457 goto unlock; 458 } 459 460 if (start) 461 timeri->ticks = timeri->cticks = ticks; 462 else if (!timeri->cticks) 463 timeri->cticks = 1; 464 timeri->pticks = 0; 465 466 list_move_tail(&timeri->active_list, &timer->active_list_head); 467 if (timer->running) { 468 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE) 469 goto __start_now; 470 timer->flags |= SNDRV_TIMER_FLG_RESCHED; 471 timeri->flags |= SNDRV_TIMER_IFLG_START; 472 result = 1; /* delayed start */ 473 } else { 474 if (start) 475 timer->sticks = ticks; 476 timer->hw.start(timer); 477 __start_now: 478 timer->running++; 479 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING; 480 result = 0; 481 } 482 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START : 483 SNDRV_TIMER_EVENT_CONTINUE); 484 unlock: 485 spin_unlock_irqrestore(&timer->lock, flags); 486 return result; 487 } 488 489 /* start/continue a slave timer */ 490 static int snd_timer_start_slave(struct snd_timer_instance *timeri, 491 bool start) 492 { 493 unsigned long flags; 494 495 spin_lock_irqsave(&slave_active_lock, flags); 496 if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) { 497 spin_unlock_irqrestore(&slave_active_lock, flags); 498 return -EBUSY; 499 } 500 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING; 501 if (timeri->master && timeri->timer) { 502 spin_lock(&timeri->timer->lock); 503 list_add_tail(&timeri->active_list, 504 &timeri->master->slave_active_head); 505 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START : 506 SNDRV_TIMER_EVENT_CONTINUE); 507 spin_unlock(&timeri->timer->lock); 508 } 509 spin_unlock_irqrestore(&slave_active_lock, flags); 510 return 1; /* delayed start */ 511 } 512 513 /* stop/pause a master timer */ 514 static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop) 515 { 516 struct snd_timer *timer; 517 int result = 0; 518 unsigned long flags; 519 520 timer = timeri->timer; 521 if (!timer) 522 return -EINVAL; 523 spin_lock_irqsave(&timer->lock, flags); 524 if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING | 525 SNDRV_TIMER_IFLG_START))) { 526 result = -EBUSY; 527 goto unlock; 528 } 529 list_del_init(&timeri->ack_list); 530 list_del_init(&timeri->active_list); 531 if (timer->card && timer->card->shutdown) 532 goto unlock; 533 if (stop) { 534 timeri->cticks = timeri->ticks; 535 timeri->pticks = 0; 536 } 537 if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) && 538 !(--timer->running)) { 539 timer->hw.stop(timer); 540 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) { 541 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED; 542 snd_timer_reschedule(timer, 0); 543 if (timer->flags & SNDRV_TIMER_FLG_CHANGE) { 544 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE; 545 timer->hw.start(timer); 546 } 547 } 548 } 549 timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START); 550 if (stop) 551 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED; 552 else 553 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED; 554 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP : 555 SNDRV_TIMER_EVENT_CONTINUE); 556 unlock: 557 spin_unlock_irqrestore(&timer->lock, flags); 558 return result; 559 } 560 561 /* stop/pause a slave timer */ 562 static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop) 563 { 564 unsigned long flags; 565 566 spin_lock_irqsave(&slave_active_lock, flags); 567 if (!(timeri->flags & SNDRV_TIMER_IFLG_RUNNING)) { 568 spin_unlock_irqrestore(&slave_active_lock, flags); 569 return -EBUSY; 570 } 571 timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING; 572 if (timeri->timer) { 573 spin_lock(&timeri->timer->lock); 574 list_del_init(&timeri->ack_list); 575 list_del_init(&timeri->active_list); 576 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP : 577 SNDRV_TIMER_EVENT_CONTINUE); 578 spin_unlock(&timeri->timer->lock); 579 } 580 spin_unlock_irqrestore(&slave_active_lock, flags); 581 return 0; 582 } 583 584 /* 585 * start the timer instance 586 */ 587 int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks) 588 { 589 if (timeri == NULL || ticks < 1) 590 return -EINVAL; 591 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) 592 return snd_timer_start_slave(timeri, true); 593 else 594 return snd_timer_start1(timeri, true, ticks); 595 } 596 EXPORT_SYMBOL(snd_timer_start); 597 598 /* 599 * stop the timer instance. 600 * 601 * do not call this from the timer callback! 602 */ 603 int snd_timer_stop(struct snd_timer_instance *timeri) 604 { 605 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) 606 return snd_timer_stop_slave(timeri, true); 607 else 608 return snd_timer_stop1(timeri, true); 609 } 610 EXPORT_SYMBOL(snd_timer_stop); 611 612 /* 613 * start again.. the tick is kept. 614 */ 615 int snd_timer_continue(struct snd_timer_instance *timeri) 616 { 617 /* timer can continue only after pause */ 618 if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED)) 619 return -EINVAL; 620 621 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) 622 return snd_timer_start_slave(timeri, false); 623 else 624 return snd_timer_start1(timeri, false, 0); 625 } 626 EXPORT_SYMBOL(snd_timer_continue); 627 628 /* 629 * pause.. remember the ticks left 630 */ 631 int snd_timer_pause(struct snd_timer_instance * timeri) 632 { 633 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE) 634 return snd_timer_stop_slave(timeri, false); 635 else 636 return snd_timer_stop1(timeri, false); 637 } 638 EXPORT_SYMBOL(snd_timer_pause); 639 640 /* 641 * reschedule the timer 642 * 643 * start pending instances and check the scheduling ticks. 644 * when the scheduling ticks is changed set CHANGE flag to reprogram the timer. 645 */ 646 static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left) 647 { 648 struct snd_timer_instance *ti; 649 unsigned long ticks = ~0UL; 650 651 list_for_each_entry(ti, &timer->active_list_head, active_list) { 652 if (ti->flags & SNDRV_TIMER_IFLG_START) { 653 ti->flags &= ~SNDRV_TIMER_IFLG_START; 654 ti->flags |= SNDRV_TIMER_IFLG_RUNNING; 655 timer->running++; 656 } 657 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) { 658 if (ticks > ti->cticks) 659 ticks = ti->cticks; 660 } 661 } 662 if (ticks == ~0UL) { 663 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED; 664 return; 665 } 666 if (ticks > timer->hw.ticks) 667 ticks = timer->hw.ticks; 668 if (ticks_left != ticks) 669 timer->flags |= SNDRV_TIMER_FLG_CHANGE; 670 timer->sticks = ticks; 671 } 672 673 /* 674 * timer tasklet 675 * 676 */ 677 static void snd_timer_tasklet(unsigned long arg) 678 { 679 struct snd_timer *timer = (struct snd_timer *) arg; 680 struct snd_timer_instance *ti; 681 struct list_head *p; 682 unsigned long resolution, ticks; 683 unsigned long flags; 684 685 if (timer->card && timer->card->shutdown) 686 return; 687 688 spin_lock_irqsave(&timer->lock, flags); 689 /* now process all callbacks */ 690 while (!list_empty(&timer->sack_list_head)) { 691 p = timer->sack_list_head.next; /* get first item */ 692 ti = list_entry(p, struct snd_timer_instance, ack_list); 693 694 /* remove from ack_list and make empty */ 695 list_del_init(p); 696 697 ticks = ti->pticks; 698 ti->pticks = 0; 699 resolution = ti->resolution; 700 701 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK; 702 spin_unlock(&timer->lock); 703 if (ti->callback) 704 ti->callback(ti, resolution, ticks); 705 spin_lock(&timer->lock); 706 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK; 707 } 708 spin_unlock_irqrestore(&timer->lock, flags); 709 } 710 711 /* 712 * timer interrupt 713 * 714 * ticks_left is usually equal to timer->sticks. 715 * 716 */ 717 void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left) 718 { 719 struct snd_timer_instance *ti, *ts, *tmp; 720 unsigned long resolution, ticks; 721 struct list_head *p, *ack_list_head; 722 unsigned long flags; 723 int use_tasklet = 0; 724 725 if (timer == NULL) 726 return; 727 728 if (timer->card && timer->card->shutdown) 729 return; 730 731 spin_lock_irqsave(&timer->lock, flags); 732 733 /* remember the current resolution */ 734 if (timer->hw.c_resolution) 735 resolution = timer->hw.c_resolution(timer); 736 else 737 resolution = timer->hw.resolution; 738 739 /* loop for all active instances 740 * Here we cannot use list_for_each_entry because the active_list of a 741 * processed instance is relinked to done_list_head before the callback 742 * is called. 743 */ 744 list_for_each_entry_safe(ti, tmp, &timer->active_list_head, 745 active_list) { 746 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING)) 747 continue; 748 ti->pticks += ticks_left; 749 ti->resolution = resolution; 750 if (ti->cticks < ticks_left) 751 ti->cticks = 0; 752 else 753 ti->cticks -= ticks_left; 754 if (ti->cticks) /* not expired */ 755 continue; 756 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) { 757 ti->cticks = ti->ticks; 758 } else { 759 ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING; 760 --timer->running; 761 list_del_init(&ti->active_list); 762 } 763 if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) || 764 (ti->flags & SNDRV_TIMER_IFLG_FAST)) 765 ack_list_head = &timer->ack_list_head; 766 else 767 ack_list_head = &timer->sack_list_head; 768 if (list_empty(&ti->ack_list)) 769 list_add_tail(&ti->ack_list, ack_list_head); 770 list_for_each_entry(ts, &ti->slave_active_head, active_list) { 771 ts->pticks = ti->pticks; 772 ts->resolution = resolution; 773 if (list_empty(&ts->ack_list)) 774 list_add_tail(&ts->ack_list, ack_list_head); 775 } 776 } 777 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) 778 snd_timer_reschedule(timer, timer->sticks); 779 if (timer->running) { 780 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) { 781 timer->hw.stop(timer); 782 timer->flags |= SNDRV_TIMER_FLG_CHANGE; 783 } 784 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) || 785 (timer->flags & SNDRV_TIMER_FLG_CHANGE)) { 786 /* restart timer */ 787 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE; 788 timer->hw.start(timer); 789 } 790 } else { 791 timer->hw.stop(timer); 792 } 793 794 /* now process all fast callbacks */ 795 while (!list_empty(&timer->ack_list_head)) { 796 p = timer->ack_list_head.next; /* get first item */ 797 ti = list_entry(p, struct snd_timer_instance, ack_list); 798 799 /* remove from ack_list and make empty */ 800 list_del_init(p); 801 802 ticks = ti->pticks; 803 ti->pticks = 0; 804 805 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK; 806 spin_unlock(&timer->lock); 807 if (ti->callback) 808 ti->callback(ti, resolution, ticks); 809 spin_lock(&timer->lock); 810 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK; 811 } 812 813 /* do we have any slow callbacks? */ 814 use_tasklet = !list_empty(&timer->sack_list_head); 815 spin_unlock_irqrestore(&timer->lock, flags); 816 817 if (use_tasklet) 818 tasklet_schedule(&timer->task_queue); 819 } 820 EXPORT_SYMBOL(snd_timer_interrupt); 821 822 /* 823 824 */ 825 826 int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid, 827 struct snd_timer **rtimer) 828 { 829 struct snd_timer *timer; 830 int err; 831 static struct snd_device_ops ops = { 832 .dev_free = snd_timer_dev_free, 833 .dev_register = snd_timer_dev_register, 834 .dev_disconnect = snd_timer_dev_disconnect, 835 }; 836 837 if (snd_BUG_ON(!tid)) 838 return -EINVAL; 839 if (rtimer) 840 *rtimer = NULL; 841 timer = kzalloc(sizeof(*timer), GFP_KERNEL); 842 if (!timer) 843 return -ENOMEM; 844 timer->tmr_class = tid->dev_class; 845 timer->card = card; 846 timer->tmr_device = tid->device; 847 timer->tmr_subdevice = tid->subdevice; 848 if (id) 849 strlcpy(timer->id, id, sizeof(timer->id)); 850 timer->sticks = 1; 851 INIT_LIST_HEAD(&timer->device_list); 852 INIT_LIST_HEAD(&timer->open_list_head); 853 INIT_LIST_HEAD(&timer->active_list_head); 854 INIT_LIST_HEAD(&timer->ack_list_head); 855 INIT_LIST_HEAD(&timer->sack_list_head); 856 spin_lock_init(&timer->lock); 857 tasklet_init(&timer->task_queue, snd_timer_tasklet, 858 (unsigned long)timer); 859 if (card != NULL) { 860 timer->module = card->module; 861 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops); 862 if (err < 0) { 863 snd_timer_free(timer); 864 return err; 865 } 866 } 867 if (rtimer) 868 *rtimer = timer; 869 return 0; 870 } 871 EXPORT_SYMBOL(snd_timer_new); 872 873 static int snd_timer_free(struct snd_timer *timer) 874 { 875 if (!timer) 876 return 0; 877 878 mutex_lock(®ister_mutex); 879 if (! list_empty(&timer->open_list_head)) { 880 struct list_head *p, *n; 881 struct snd_timer_instance *ti; 882 pr_warn("ALSA: timer %p is busy?\n", timer); 883 list_for_each_safe(p, n, &timer->open_list_head) { 884 list_del_init(p); 885 ti = list_entry(p, struct snd_timer_instance, open_list); 886 ti->timer = NULL; 887 } 888 } 889 list_del(&timer->device_list); 890 mutex_unlock(®ister_mutex); 891 892 if (timer->private_free) 893 timer->private_free(timer); 894 kfree(timer); 895 return 0; 896 } 897 898 static int snd_timer_dev_free(struct snd_device *device) 899 { 900 struct snd_timer *timer = device->device_data; 901 return snd_timer_free(timer); 902 } 903 904 static int snd_timer_dev_register(struct snd_device *dev) 905 { 906 struct snd_timer *timer = dev->device_data; 907 struct snd_timer *timer1; 908 909 if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop)) 910 return -ENXIO; 911 if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) && 912 !timer->hw.resolution && timer->hw.c_resolution == NULL) 913 return -EINVAL; 914 915 mutex_lock(®ister_mutex); 916 list_for_each_entry(timer1, &snd_timer_list, device_list) { 917 if (timer1->tmr_class > timer->tmr_class) 918 break; 919 if (timer1->tmr_class < timer->tmr_class) 920 continue; 921 if (timer1->card && timer->card) { 922 if (timer1->card->number > timer->card->number) 923 break; 924 if (timer1->card->number < timer->card->number) 925 continue; 926 } 927 if (timer1->tmr_device > timer->tmr_device) 928 break; 929 if (timer1->tmr_device < timer->tmr_device) 930 continue; 931 if (timer1->tmr_subdevice > timer->tmr_subdevice) 932 break; 933 if (timer1->tmr_subdevice < timer->tmr_subdevice) 934 continue; 935 /* conflicts.. */ 936 mutex_unlock(®ister_mutex); 937 return -EBUSY; 938 } 939 list_add_tail(&timer->device_list, &timer1->device_list); 940 mutex_unlock(®ister_mutex); 941 return 0; 942 } 943 944 static int snd_timer_dev_disconnect(struct snd_device *device) 945 { 946 struct snd_timer *timer = device->device_data; 947 struct snd_timer_instance *ti; 948 949 mutex_lock(®ister_mutex); 950 list_del_init(&timer->device_list); 951 /* wake up pending sleepers */ 952 list_for_each_entry(ti, &timer->open_list_head, open_list) { 953 if (ti->disconnect) 954 ti->disconnect(ti); 955 } 956 mutex_unlock(®ister_mutex); 957 return 0; 958 } 959 960 void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp) 961 { 962 unsigned long flags; 963 unsigned long resolution = 0; 964 struct snd_timer_instance *ti, *ts; 965 966 if (timer->card && timer->card->shutdown) 967 return; 968 if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)) 969 return; 970 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART || 971 event > SNDRV_TIMER_EVENT_MRESUME)) 972 return; 973 spin_lock_irqsave(&timer->lock, flags); 974 if (event == SNDRV_TIMER_EVENT_MSTART || 975 event == SNDRV_TIMER_EVENT_MCONTINUE || 976 event == SNDRV_TIMER_EVENT_MRESUME) { 977 if (timer->hw.c_resolution) 978 resolution = timer->hw.c_resolution(timer); 979 else 980 resolution = timer->hw.resolution; 981 } 982 list_for_each_entry(ti, &timer->active_list_head, active_list) { 983 if (ti->ccallback) 984 ti->ccallback(ti, event, tstamp, resolution); 985 list_for_each_entry(ts, &ti->slave_active_head, active_list) 986 if (ts->ccallback) 987 ts->ccallback(ts, event, tstamp, resolution); 988 } 989 spin_unlock_irqrestore(&timer->lock, flags); 990 } 991 EXPORT_SYMBOL(snd_timer_notify); 992 993 /* 994 * exported functions for global timers 995 */ 996 int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer) 997 { 998 struct snd_timer_id tid; 999 1000 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL; 1001 tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE; 1002 tid.card = -1; 1003 tid.device = device; 1004 tid.subdevice = 0; 1005 return snd_timer_new(NULL, id, &tid, rtimer); 1006 } 1007 EXPORT_SYMBOL(snd_timer_global_new); 1008 1009 int snd_timer_global_free(struct snd_timer *timer) 1010 { 1011 return snd_timer_free(timer); 1012 } 1013 EXPORT_SYMBOL(snd_timer_global_free); 1014 1015 int snd_timer_global_register(struct snd_timer *timer) 1016 { 1017 struct snd_device dev; 1018 1019 memset(&dev, 0, sizeof(dev)); 1020 dev.device_data = timer; 1021 return snd_timer_dev_register(&dev); 1022 } 1023 EXPORT_SYMBOL(snd_timer_global_register); 1024 1025 /* 1026 * System timer 1027 */ 1028 1029 struct snd_timer_system_private { 1030 struct timer_list tlist; 1031 unsigned long last_expires; 1032 unsigned long last_jiffies; 1033 unsigned long correction; 1034 }; 1035 1036 static void snd_timer_s_function(unsigned long data) 1037 { 1038 struct snd_timer *timer = (struct snd_timer *)data; 1039 struct snd_timer_system_private *priv = timer->private_data; 1040 unsigned long jiff = jiffies; 1041 if (time_after(jiff, priv->last_expires)) 1042 priv->correction += (long)jiff - (long)priv->last_expires; 1043 snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies); 1044 } 1045 1046 static int snd_timer_s_start(struct snd_timer * timer) 1047 { 1048 struct snd_timer_system_private *priv; 1049 unsigned long njiff; 1050 1051 priv = (struct snd_timer_system_private *) timer->private_data; 1052 njiff = (priv->last_jiffies = jiffies); 1053 if (priv->correction > timer->sticks - 1) { 1054 priv->correction -= timer->sticks - 1; 1055 njiff++; 1056 } else { 1057 njiff += timer->sticks - priv->correction; 1058 priv->correction = 0; 1059 } 1060 priv->last_expires = njiff; 1061 mod_timer(&priv->tlist, njiff); 1062 return 0; 1063 } 1064 1065 static int snd_timer_s_stop(struct snd_timer * timer) 1066 { 1067 struct snd_timer_system_private *priv; 1068 unsigned long jiff; 1069 1070 priv = (struct snd_timer_system_private *) timer->private_data; 1071 del_timer(&priv->tlist); 1072 jiff = jiffies; 1073 if (time_before(jiff, priv->last_expires)) 1074 timer->sticks = priv->last_expires - jiff; 1075 else 1076 timer->sticks = 1; 1077 priv->correction = 0; 1078 return 0; 1079 } 1080 1081 static int snd_timer_s_close(struct snd_timer *timer) 1082 { 1083 struct snd_timer_system_private *priv; 1084 1085 priv = (struct snd_timer_system_private *)timer->private_data; 1086 del_timer_sync(&priv->tlist); 1087 return 0; 1088 } 1089 1090 static struct snd_timer_hardware snd_timer_system = 1091 { 1092 .flags = SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET, 1093 .resolution = 1000000000L / HZ, 1094 .ticks = 10000000L, 1095 .close = snd_timer_s_close, 1096 .start = snd_timer_s_start, 1097 .stop = snd_timer_s_stop 1098 }; 1099 1100 static void snd_timer_free_system(struct snd_timer *timer) 1101 { 1102 kfree(timer->private_data); 1103 } 1104 1105 static int snd_timer_register_system(void) 1106 { 1107 struct snd_timer *timer; 1108 struct snd_timer_system_private *priv; 1109 int err; 1110 1111 err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer); 1112 if (err < 0) 1113 return err; 1114 strcpy(timer->name, "system timer"); 1115 timer->hw = snd_timer_system; 1116 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 1117 if (priv == NULL) { 1118 snd_timer_free(timer); 1119 return -ENOMEM; 1120 } 1121 setup_timer(&priv->tlist, snd_timer_s_function, (unsigned long) timer); 1122 timer->private_data = priv; 1123 timer->private_free = snd_timer_free_system; 1124 return snd_timer_global_register(timer); 1125 } 1126 1127 #ifdef CONFIG_SND_PROC_FS 1128 /* 1129 * Info interface 1130 */ 1131 1132 static void snd_timer_proc_read(struct snd_info_entry *entry, 1133 struct snd_info_buffer *buffer) 1134 { 1135 struct snd_timer *timer; 1136 struct snd_timer_instance *ti; 1137 1138 mutex_lock(®ister_mutex); 1139 list_for_each_entry(timer, &snd_timer_list, device_list) { 1140 if (timer->card && timer->card->shutdown) 1141 continue; 1142 switch (timer->tmr_class) { 1143 case SNDRV_TIMER_CLASS_GLOBAL: 1144 snd_iprintf(buffer, "G%i: ", timer->tmr_device); 1145 break; 1146 case SNDRV_TIMER_CLASS_CARD: 1147 snd_iprintf(buffer, "C%i-%i: ", 1148 timer->card->number, timer->tmr_device); 1149 break; 1150 case SNDRV_TIMER_CLASS_PCM: 1151 snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number, 1152 timer->tmr_device, timer->tmr_subdevice); 1153 break; 1154 default: 1155 snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class, 1156 timer->card ? timer->card->number : -1, 1157 timer->tmr_device, timer->tmr_subdevice); 1158 } 1159 snd_iprintf(buffer, "%s :", timer->name); 1160 if (timer->hw.resolution) 1161 snd_iprintf(buffer, " %lu.%03luus (%lu ticks)", 1162 timer->hw.resolution / 1000, 1163 timer->hw.resolution % 1000, 1164 timer->hw.ticks); 1165 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE) 1166 snd_iprintf(buffer, " SLAVE"); 1167 snd_iprintf(buffer, "\n"); 1168 list_for_each_entry(ti, &timer->open_list_head, open_list) 1169 snd_iprintf(buffer, " Client %s : %s\n", 1170 ti->owner ? ti->owner : "unknown", 1171 ti->flags & (SNDRV_TIMER_IFLG_START | 1172 SNDRV_TIMER_IFLG_RUNNING) 1173 ? "running" : "stopped"); 1174 } 1175 mutex_unlock(®ister_mutex); 1176 } 1177 1178 static struct snd_info_entry *snd_timer_proc_entry; 1179 1180 static void __init snd_timer_proc_init(void) 1181 { 1182 struct snd_info_entry *entry; 1183 1184 entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL); 1185 if (entry != NULL) { 1186 entry->c.text.read = snd_timer_proc_read; 1187 if (snd_info_register(entry) < 0) { 1188 snd_info_free_entry(entry); 1189 entry = NULL; 1190 } 1191 } 1192 snd_timer_proc_entry = entry; 1193 } 1194 1195 static void __exit snd_timer_proc_done(void) 1196 { 1197 snd_info_free_entry(snd_timer_proc_entry); 1198 } 1199 #else /* !CONFIG_SND_PROC_FS */ 1200 #define snd_timer_proc_init() 1201 #define snd_timer_proc_done() 1202 #endif 1203 1204 /* 1205 * USER SPACE interface 1206 */ 1207 1208 static void snd_timer_user_interrupt(struct snd_timer_instance *timeri, 1209 unsigned long resolution, 1210 unsigned long ticks) 1211 { 1212 struct snd_timer_user *tu = timeri->callback_data; 1213 struct snd_timer_read *r; 1214 int prev; 1215 1216 spin_lock(&tu->qlock); 1217 if (tu->qused > 0) { 1218 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1; 1219 r = &tu->queue[prev]; 1220 if (r->resolution == resolution) { 1221 r->ticks += ticks; 1222 goto __wake; 1223 } 1224 } 1225 if (tu->qused >= tu->queue_size) { 1226 tu->overrun++; 1227 } else { 1228 r = &tu->queue[tu->qtail++]; 1229 tu->qtail %= tu->queue_size; 1230 r->resolution = resolution; 1231 r->ticks = ticks; 1232 tu->qused++; 1233 } 1234 __wake: 1235 spin_unlock(&tu->qlock); 1236 kill_fasync(&tu->fasync, SIGIO, POLL_IN); 1237 wake_up(&tu->qchange_sleep); 1238 } 1239 1240 static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu, 1241 struct snd_timer_tread *tread) 1242 { 1243 if (tu->qused >= tu->queue_size) { 1244 tu->overrun++; 1245 } else { 1246 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread)); 1247 tu->qtail %= tu->queue_size; 1248 tu->qused++; 1249 } 1250 } 1251 1252 static void snd_timer_user_ccallback(struct snd_timer_instance *timeri, 1253 int event, 1254 struct timespec *tstamp, 1255 unsigned long resolution) 1256 { 1257 struct snd_timer_user *tu = timeri->callback_data; 1258 struct snd_timer_tread r1; 1259 unsigned long flags; 1260 1261 if (event >= SNDRV_TIMER_EVENT_START && 1262 event <= SNDRV_TIMER_EVENT_PAUSE) 1263 tu->tstamp = *tstamp; 1264 if ((tu->filter & (1 << event)) == 0 || !tu->tread) 1265 return; 1266 memset(&r1, 0, sizeof(r1)); 1267 r1.event = event; 1268 r1.tstamp = *tstamp; 1269 r1.val = resolution; 1270 spin_lock_irqsave(&tu->qlock, flags); 1271 snd_timer_user_append_to_tqueue(tu, &r1); 1272 spin_unlock_irqrestore(&tu->qlock, flags); 1273 kill_fasync(&tu->fasync, SIGIO, POLL_IN); 1274 wake_up(&tu->qchange_sleep); 1275 } 1276 1277 static void snd_timer_user_disconnect(struct snd_timer_instance *timeri) 1278 { 1279 struct snd_timer_user *tu = timeri->callback_data; 1280 1281 tu->disconnected = true; 1282 wake_up(&tu->qchange_sleep); 1283 } 1284 1285 static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri, 1286 unsigned long resolution, 1287 unsigned long ticks) 1288 { 1289 struct snd_timer_user *tu = timeri->callback_data; 1290 struct snd_timer_tread *r, r1; 1291 struct timespec tstamp; 1292 int prev, append = 0; 1293 1294 memset(&r1, 0, sizeof(r1)); 1295 memset(&tstamp, 0, sizeof(tstamp)); 1296 spin_lock(&tu->qlock); 1297 if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) | 1298 (1 << SNDRV_TIMER_EVENT_TICK))) == 0) { 1299 spin_unlock(&tu->qlock); 1300 return; 1301 } 1302 if (tu->last_resolution != resolution || ticks > 0) { 1303 if (timer_tstamp_monotonic) 1304 ktime_get_ts(&tstamp); 1305 else 1306 getnstimeofday(&tstamp); 1307 } 1308 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) && 1309 tu->last_resolution != resolution) { 1310 r1.event = SNDRV_TIMER_EVENT_RESOLUTION; 1311 r1.tstamp = tstamp; 1312 r1.val = resolution; 1313 snd_timer_user_append_to_tqueue(tu, &r1); 1314 tu->last_resolution = resolution; 1315 append++; 1316 } 1317 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0) 1318 goto __wake; 1319 if (ticks == 0) 1320 goto __wake; 1321 if (tu->qused > 0) { 1322 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1; 1323 r = &tu->tqueue[prev]; 1324 if (r->event == SNDRV_TIMER_EVENT_TICK) { 1325 r->tstamp = tstamp; 1326 r->val += ticks; 1327 append++; 1328 goto __wake; 1329 } 1330 } 1331 r1.event = SNDRV_TIMER_EVENT_TICK; 1332 r1.tstamp = tstamp; 1333 r1.val = ticks; 1334 snd_timer_user_append_to_tqueue(tu, &r1); 1335 append++; 1336 __wake: 1337 spin_unlock(&tu->qlock); 1338 if (append == 0) 1339 return; 1340 kill_fasync(&tu->fasync, SIGIO, POLL_IN); 1341 wake_up(&tu->qchange_sleep); 1342 } 1343 1344 static int realloc_user_queue(struct snd_timer_user *tu, int size) 1345 { 1346 struct snd_timer_read *queue = NULL; 1347 struct snd_timer_tread *tqueue = NULL; 1348 1349 if (tu->tread) { 1350 tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL); 1351 if (!tqueue) 1352 return -ENOMEM; 1353 } else { 1354 queue = kcalloc(size, sizeof(*queue), GFP_KERNEL); 1355 if (!queue) 1356 return -ENOMEM; 1357 } 1358 1359 spin_lock_irq(&tu->qlock); 1360 kfree(tu->queue); 1361 kfree(tu->tqueue); 1362 tu->queue_size = size; 1363 tu->queue = queue; 1364 tu->tqueue = tqueue; 1365 tu->qhead = tu->qtail = tu->qused = 0; 1366 spin_unlock_irq(&tu->qlock); 1367 1368 return 0; 1369 } 1370 1371 static int snd_timer_user_open(struct inode *inode, struct file *file) 1372 { 1373 struct snd_timer_user *tu; 1374 int err; 1375 1376 err = nonseekable_open(inode, file); 1377 if (err < 0) 1378 return err; 1379 1380 tu = kzalloc(sizeof(*tu), GFP_KERNEL); 1381 if (tu == NULL) 1382 return -ENOMEM; 1383 spin_lock_init(&tu->qlock); 1384 init_waitqueue_head(&tu->qchange_sleep); 1385 mutex_init(&tu->ioctl_lock); 1386 tu->ticks = 1; 1387 if (realloc_user_queue(tu, 128) < 0) { 1388 kfree(tu); 1389 return -ENOMEM; 1390 } 1391 file->private_data = tu; 1392 return 0; 1393 } 1394 1395 static int snd_timer_user_release(struct inode *inode, struct file *file) 1396 { 1397 struct snd_timer_user *tu; 1398 1399 if (file->private_data) { 1400 tu = file->private_data; 1401 file->private_data = NULL; 1402 mutex_lock(&tu->ioctl_lock); 1403 if (tu->timeri) 1404 snd_timer_close(tu->timeri); 1405 mutex_unlock(&tu->ioctl_lock); 1406 kfree(tu->queue); 1407 kfree(tu->tqueue); 1408 kfree(tu); 1409 } 1410 return 0; 1411 } 1412 1413 static void snd_timer_user_zero_id(struct snd_timer_id *id) 1414 { 1415 id->dev_class = SNDRV_TIMER_CLASS_NONE; 1416 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE; 1417 id->card = -1; 1418 id->device = -1; 1419 id->subdevice = -1; 1420 } 1421 1422 static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer) 1423 { 1424 id->dev_class = timer->tmr_class; 1425 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE; 1426 id->card = timer->card ? timer->card->number : -1; 1427 id->device = timer->tmr_device; 1428 id->subdevice = timer->tmr_subdevice; 1429 } 1430 1431 static int snd_timer_user_next_device(struct snd_timer_id __user *_tid) 1432 { 1433 struct snd_timer_id id; 1434 struct snd_timer *timer; 1435 struct list_head *p; 1436 1437 if (copy_from_user(&id, _tid, sizeof(id))) 1438 return -EFAULT; 1439 mutex_lock(®ister_mutex); 1440 if (id.dev_class < 0) { /* first item */ 1441 if (list_empty(&snd_timer_list)) 1442 snd_timer_user_zero_id(&id); 1443 else { 1444 timer = list_entry(snd_timer_list.next, 1445 struct snd_timer, device_list); 1446 snd_timer_user_copy_id(&id, timer); 1447 } 1448 } else { 1449 switch (id.dev_class) { 1450 case SNDRV_TIMER_CLASS_GLOBAL: 1451 id.device = id.device < 0 ? 0 : id.device + 1; 1452 list_for_each(p, &snd_timer_list) { 1453 timer = list_entry(p, struct snd_timer, device_list); 1454 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) { 1455 snd_timer_user_copy_id(&id, timer); 1456 break; 1457 } 1458 if (timer->tmr_device >= id.device) { 1459 snd_timer_user_copy_id(&id, timer); 1460 break; 1461 } 1462 } 1463 if (p == &snd_timer_list) 1464 snd_timer_user_zero_id(&id); 1465 break; 1466 case SNDRV_TIMER_CLASS_CARD: 1467 case SNDRV_TIMER_CLASS_PCM: 1468 if (id.card < 0) { 1469 id.card = 0; 1470 } else { 1471 if (id.device < 0) { 1472 id.device = 0; 1473 } else { 1474 if (id.subdevice < 0) 1475 id.subdevice = 0; 1476 else 1477 id.subdevice++; 1478 } 1479 } 1480 list_for_each(p, &snd_timer_list) { 1481 timer = list_entry(p, struct snd_timer, device_list); 1482 if (timer->tmr_class > id.dev_class) { 1483 snd_timer_user_copy_id(&id, timer); 1484 break; 1485 } 1486 if (timer->tmr_class < id.dev_class) 1487 continue; 1488 if (timer->card->number > id.card) { 1489 snd_timer_user_copy_id(&id, timer); 1490 break; 1491 } 1492 if (timer->card->number < id.card) 1493 continue; 1494 if (timer->tmr_device > id.device) { 1495 snd_timer_user_copy_id(&id, timer); 1496 break; 1497 } 1498 if (timer->tmr_device < id.device) 1499 continue; 1500 if (timer->tmr_subdevice > id.subdevice) { 1501 snd_timer_user_copy_id(&id, timer); 1502 break; 1503 } 1504 if (timer->tmr_subdevice < id.subdevice) 1505 continue; 1506 snd_timer_user_copy_id(&id, timer); 1507 break; 1508 } 1509 if (p == &snd_timer_list) 1510 snd_timer_user_zero_id(&id); 1511 break; 1512 default: 1513 snd_timer_user_zero_id(&id); 1514 } 1515 } 1516 mutex_unlock(®ister_mutex); 1517 if (copy_to_user(_tid, &id, sizeof(*_tid))) 1518 return -EFAULT; 1519 return 0; 1520 } 1521 1522 static int snd_timer_user_ginfo(struct file *file, 1523 struct snd_timer_ginfo __user *_ginfo) 1524 { 1525 struct snd_timer_ginfo *ginfo; 1526 struct snd_timer_id tid; 1527 struct snd_timer *t; 1528 struct list_head *p; 1529 int err = 0; 1530 1531 ginfo = memdup_user(_ginfo, sizeof(*ginfo)); 1532 if (IS_ERR(ginfo)) 1533 return PTR_ERR(ginfo); 1534 1535 tid = ginfo->tid; 1536 memset(ginfo, 0, sizeof(*ginfo)); 1537 ginfo->tid = tid; 1538 mutex_lock(®ister_mutex); 1539 t = snd_timer_find(&tid); 1540 if (t != NULL) { 1541 ginfo->card = t->card ? t->card->number : -1; 1542 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE) 1543 ginfo->flags |= SNDRV_TIMER_FLG_SLAVE; 1544 strlcpy(ginfo->id, t->id, sizeof(ginfo->id)); 1545 strlcpy(ginfo->name, t->name, sizeof(ginfo->name)); 1546 ginfo->resolution = t->hw.resolution; 1547 if (t->hw.resolution_min > 0) { 1548 ginfo->resolution_min = t->hw.resolution_min; 1549 ginfo->resolution_max = t->hw.resolution_max; 1550 } 1551 list_for_each(p, &t->open_list_head) { 1552 ginfo->clients++; 1553 } 1554 } else { 1555 err = -ENODEV; 1556 } 1557 mutex_unlock(®ister_mutex); 1558 if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo))) 1559 err = -EFAULT; 1560 kfree(ginfo); 1561 return err; 1562 } 1563 1564 static int timer_set_gparams(struct snd_timer_gparams *gparams) 1565 { 1566 struct snd_timer *t; 1567 int err; 1568 1569 mutex_lock(®ister_mutex); 1570 t = snd_timer_find(&gparams->tid); 1571 if (!t) { 1572 err = -ENODEV; 1573 goto _error; 1574 } 1575 if (!list_empty(&t->open_list_head)) { 1576 err = -EBUSY; 1577 goto _error; 1578 } 1579 if (!t->hw.set_period) { 1580 err = -ENOSYS; 1581 goto _error; 1582 } 1583 err = t->hw.set_period(t, gparams->period_num, gparams->period_den); 1584 _error: 1585 mutex_unlock(®ister_mutex); 1586 return err; 1587 } 1588 1589 static int snd_timer_user_gparams(struct file *file, 1590 struct snd_timer_gparams __user *_gparams) 1591 { 1592 struct snd_timer_gparams gparams; 1593 1594 if (copy_from_user(&gparams, _gparams, sizeof(gparams))) 1595 return -EFAULT; 1596 return timer_set_gparams(&gparams); 1597 } 1598 1599 static int snd_timer_user_gstatus(struct file *file, 1600 struct snd_timer_gstatus __user *_gstatus) 1601 { 1602 struct snd_timer_gstatus gstatus; 1603 struct snd_timer_id tid; 1604 struct snd_timer *t; 1605 int err = 0; 1606 1607 if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus))) 1608 return -EFAULT; 1609 tid = gstatus.tid; 1610 memset(&gstatus, 0, sizeof(gstatus)); 1611 gstatus.tid = tid; 1612 mutex_lock(®ister_mutex); 1613 t = snd_timer_find(&tid); 1614 if (t != NULL) { 1615 if (t->hw.c_resolution) 1616 gstatus.resolution = t->hw.c_resolution(t); 1617 else 1618 gstatus.resolution = t->hw.resolution; 1619 if (t->hw.precise_resolution) { 1620 t->hw.precise_resolution(t, &gstatus.resolution_num, 1621 &gstatus.resolution_den); 1622 } else { 1623 gstatus.resolution_num = gstatus.resolution; 1624 gstatus.resolution_den = 1000000000uL; 1625 } 1626 } else { 1627 err = -ENODEV; 1628 } 1629 mutex_unlock(®ister_mutex); 1630 if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus))) 1631 err = -EFAULT; 1632 return err; 1633 } 1634 1635 static int snd_timer_user_tselect(struct file *file, 1636 struct snd_timer_select __user *_tselect) 1637 { 1638 struct snd_timer_user *tu; 1639 struct snd_timer_select tselect; 1640 char str[32]; 1641 int err = 0; 1642 1643 tu = file->private_data; 1644 if (tu->timeri) { 1645 snd_timer_close(tu->timeri); 1646 tu->timeri = NULL; 1647 } 1648 if (copy_from_user(&tselect, _tselect, sizeof(tselect))) { 1649 err = -EFAULT; 1650 goto __err; 1651 } 1652 sprintf(str, "application %i", current->pid); 1653 if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE) 1654 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION; 1655 err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid); 1656 if (err < 0) 1657 goto __err; 1658 1659 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST; 1660 tu->timeri->callback = tu->tread 1661 ? snd_timer_user_tinterrupt : snd_timer_user_interrupt; 1662 tu->timeri->ccallback = snd_timer_user_ccallback; 1663 tu->timeri->callback_data = (void *)tu; 1664 tu->timeri->disconnect = snd_timer_user_disconnect; 1665 1666 __err: 1667 return err; 1668 } 1669 1670 static int snd_timer_user_info(struct file *file, 1671 struct snd_timer_info __user *_info) 1672 { 1673 struct snd_timer_user *tu; 1674 struct snd_timer_info *info; 1675 struct snd_timer *t; 1676 int err = 0; 1677 1678 tu = file->private_data; 1679 if (!tu->timeri) 1680 return -EBADFD; 1681 t = tu->timeri->timer; 1682 if (!t) 1683 return -EBADFD; 1684 1685 info = kzalloc(sizeof(*info), GFP_KERNEL); 1686 if (! info) 1687 return -ENOMEM; 1688 info->card = t->card ? t->card->number : -1; 1689 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE) 1690 info->flags |= SNDRV_TIMER_FLG_SLAVE; 1691 strlcpy(info->id, t->id, sizeof(info->id)); 1692 strlcpy(info->name, t->name, sizeof(info->name)); 1693 info->resolution = t->hw.resolution; 1694 if (copy_to_user(_info, info, sizeof(*_info))) 1695 err = -EFAULT; 1696 kfree(info); 1697 return err; 1698 } 1699 1700 static int snd_timer_user_params(struct file *file, 1701 struct snd_timer_params __user *_params) 1702 { 1703 struct snd_timer_user *tu; 1704 struct snd_timer_params params; 1705 struct snd_timer *t; 1706 int err; 1707 1708 tu = file->private_data; 1709 if (!tu->timeri) 1710 return -EBADFD; 1711 t = tu->timeri->timer; 1712 if (!t) 1713 return -EBADFD; 1714 if (copy_from_user(¶ms, _params, sizeof(params))) 1715 return -EFAULT; 1716 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) { 1717 u64 resolution; 1718 1719 if (params.ticks < 1) { 1720 err = -EINVAL; 1721 goto _end; 1722 } 1723 1724 /* Don't allow resolution less than 1ms */ 1725 resolution = snd_timer_resolution(tu->timeri); 1726 resolution *= params.ticks; 1727 if (resolution < 1000000) { 1728 err = -EINVAL; 1729 goto _end; 1730 } 1731 } 1732 if (params.queue_size > 0 && 1733 (params.queue_size < 32 || params.queue_size > 1024)) { 1734 err = -EINVAL; 1735 goto _end; 1736 } 1737 if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)| 1738 (1<<SNDRV_TIMER_EVENT_TICK)| 1739 (1<<SNDRV_TIMER_EVENT_START)| 1740 (1<<SNDRV_TIMER_EVENT_STOP)| 1741 (1<<SNDRV_TIMER_EVENT_CONTINUE)| 1742 (1<<SNDRV_TIMER_EVENT_PAUSE)| 1743 (1<<SNDRV_TIMER_EVENT_SUSPEND)| 1744 (1<<SNDRV_TIMER_EVENT_RESUME)| 1745 (1<<SNDRV_TIMER_EVENT_MSTART)| 1746 (1<<SNDRV_TIMER_EVENT_MSTOP)| 1747 (1<<SNDRV_TIMER_EVENT_MCONTINUE)| 1748 (1<<SNDRV_TIMER_EVENT_MPAUSE)| 1749 (1<<SNDRV_TIMER_EVENT_MSUSPEND)| 1750 (1<<SNDRV_TIMER_EVENT_MRESUME))) { 1751 err = -EINVAL; 1752 goto _end; 1753 } 1754 snd_timer_stop(tu->timeri); 1755 spin_lock_irq(&t->lock); 1756 tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO| 1757 SNDRV_TIMER_IFLG_EXCLUSIVE| 1758 SNDRV_TIMER_IFLG_EARLY_EVENT); 1759 if (params.flags & SNDRV_TIMER_PSFLG_AUTO) 1760 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO; 1761 if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE) 1762 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE; 1763 if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT) 1764 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT; 1765 spin_unlock_irq(&t->lock); 1766 if (params.queue_size > 0 && 1767 (unsigned int)tu->queue_size != params.queue_size) { 1768 err = realloc_user_queue(tu, params.queue_size); 1769 if (err < 0) 1770 goto _end; 1771 } 1772 spin_lock_irq(&tu->qlock); 1773 tu->qhead = tu->qtail = tu->qused = 0; 1774 if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) { 1775 if (tu->tread) { 1776 struct snd_timer_tread tread; 1777 memset(&tread, 0, sizeof(tread)); 1778 tread.event = SNDRV_TIMER_EVENT_EARLY; 1779 tread.tstamp.tv_sec = 0; 1780 tread.tstamp.tv_nsec = 0; 1781 tread.val = 0; 1782 snd_timer_user_append_to_tqueue(tu, &tread); 1783 } else { 1784 struct snd_timer_read *r = &tu->queue[0]; 1785 r->resolution = 0; 1786 r->ticks = 0; 1787 tu->qused++; 1788 tu->qtail++; 1789 } 1790 } 1791 tu->filter = params.filter; 1792 tu->ticks = params.ticks; 1793 spin_unlock_irq(&tu->qlock); 1794 err = 0; 1795 _end: 1796 if (copy_to_user(_params, ¶ms, sizeof(params))) 1797 return -EFAULT; 1798 return err; 1799 } 1800 1801 static int snd_timer_user_status(struct file *file, 1802 struct snd_timer_status __user *_status) 1803 { 1804 struct snd_timer_user *tu; 1805 struct snd_timer_status status; 1806 1807 tu = file->private_data; 1808 if (!tu->timeri) 1809 return -EBADFD; 1810 memset(&status, 0, sizeof(status)); 1811 status.tstamp = tu->tstamp; 1812 status.resolution = snd_timer_resolution(tu->timeri); 1813 status.lost = tu->timeri->lost; 1814 status.overrun = tu->overrun; 1815 spin_lock_irq(&tu->qlock); 1816 status.queue = tu->qused; 1817 spin_unlock_irq(&tu->qlock); 1818 if (copy_to_user(_status, &status, sizeof(status))) 1819 return -EFAULT; 1820 return 0; 1821 } 1822 1823 static int snd_timer_user_start(struct file *file) 1824 { 1825 int err; 1826 struct snd_timer_user *tu; 1827 1828 tu = file->private_data; 1829 if (!tu->timeri) 1830 return -EBADFD; 1831 snd_timer_stop(tu->timeri); 1832 tu->timeri->lost = 0; 1833 tu->last_resolution = 0; 1834 return (err = snd_timer_start(tu->timeri, tu->ticks)) < 0 ? err : 0; 1835 } 1836 1837 static int snd_timer_user_stop(struct file *file) 1838 { 1839 int err; 1840 struct snd_timer_user *tu; 1841 1842 tu = file->private_data; 1843 if (!tu->timeri) 1844 return -EBADFD; 1845 return (err = snd_timer_stop(tu->timeri)) < 0 ? err : 0; 1846 } 1847 1848 static int snd_timer_user_continue(struct file *file) 1849 { 1850 int err; 1851 struct snd_timer_user *tu; 1852 1853 tu = file->private_data; 1854 if (!tu->timeri) 1855 return -EBADFD; 1856 /* start timer instead of continue if it's not used before */ 1857 if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED)) 1858 return snd_timer_user_start(file); 1859 tu->timeri->lost = 0; 1860 return (err = snd_timer_continue(tu->timeri)) < 0 ? err : 0; 1861 } 1862 1863 static int snd_timer_user_pause(struct file *file) 1864 { 1865 int err; 1866 struct snd_timer_user *tu; 1867 1868 tu = file->private_data; 1869 if (!tu->timeri) 1870 return -EBADFD; 1871 return (err = snd_timer_pause(tu->timeri)) < 0 ? err : 0; 1872 } 1873 1874 enum { 1875 SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20), 1876 SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21), 1877 SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22), 1878 SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23), 1879 }; 1880 1881 static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd, 1882 unsigned long arg) 1883 { 1884 struct snd_timer_user *tu; 1885 void __user *argp = (void __user *)arg; 1886 int __user *p = argp; 1887 1888 tu = file->private_data; 1889 switch (cmd) { 1890 case SNDRV_TIMER_IOCTL_PVERSION: 1891 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0; 1892 case SNDRV_TIMER_IOCTL_NEXT_DEVICE: 1893 return snd_timer_user_next_device(argp); 1894 case SNDRV_TIMER_IOCTL_TREAD: 1895 { 1896 int xarg, old_tread; 1897 1898 if (tu->timeri) /* too late */ 1899 return -EBUSY; 1900 if (get_user(xarg, p)) 1901 return -EFAULT; 1902 old_tread = tu->tread; 1903 tu->tread = xarg ? 1 : 0; 1904 if (tu->tread != old_tread && 1905 realloc_user_queue(tu, tu->queue_size) < 0) { 1906 tu->tread = old_tread; 1907 return -ENOMEM; 1908 } 1909 return 0; 1910 } 1911 case SNDRV_TIMER_IOCTL_GINFO: 1912 return snd_timer_user_ginfo(file, argp); 1913 case SNDRV_TIMER_IOCTL_GPARAMS: 1914 return snd_timer_user_gparams(file, argp); 1915 case SNDRV_TIMER_IOCTL_GSTATUS: 1916 return snd_timer_user_gstatus(file, argp); 1917 case SNDRV_TIMER_IOCTL_SELECT: 1918 return snd_timer_user_tselect(file, argp); 1919 case SNDRV_TIMER_IOCTL_INFO: 1920 return snd_timer_user_info(file, argp); 1921 case SNDRV_TIMER_IOCTL_PARAMS: 1922 return snd_timer_user_params(file, argp); 1923 case SNDRV_TIMER_IOCTL_STATUS: 1924 return snd_timer_user_status(file, argp); 1925 case SNDRV_TIMER_IOCTL_START: 1926 case SNDRV_TIMER_IOCTL_START_OLD: 1927 return snd_timer_user_start(file); 1928 case SNDRV_TIMER_IOCTL_STOP: 1929 case SNDRV_TIMER_IOCTL_STOP_OLD: 1930 return snd_timer_user_stop(file); 1931 case SNDRV_TIMER_IOCTL_CONTINUE: 1932 case SNDRV_TIMER_IOCTL_CONTINUE_OLD: 1933 return snd_timer_user_continue(file); 1934 case SNDRV_TIMER_IOCTL_PAUSE: 1935 case SNDRV_TIMER_IOCTL_PAUSE_OLD: 1936 return snd_timer_user_pause(file); 1937 } 1938 return -ENOTTY; 1939 } 1940 1941 static long snd_timer_user_ioctl(struct file *file, unsigned int cmd, 1942 unsigned long arg) 1943 { 1944 struct snd_timer_user *tu = file->private_data; 1945 long ret; 1946 1947 mutex_lock(&tu->ioctl_lock); 1948 ret = __snd_timer_user_ioctl(file, cmd, arg); 1949 mutex_unlock(&tu->ioctl_lock); 1950 return ret; 1951 } 1952 1953 static int snd_timer_user_fasync(int fd, struct file * file, int on) 1954 { 1955 struct snd_timer_user *tu; 1956 1957 tu = file->private_data; 1958 return fasync_helper(fd, file, on, &tu->fasync); 1959 } 1960 1961 static ssize_t snd_timer_user_read(struct file *file, char __user *buffer, 1962 size_t count, loff_t *offset) 1963 { 1964 struct snd_timer_user *tu; 1965 long result = 0, unit; 1966 int qhead; 1967 int err = 0; 1968 1969 tu = file->private_data; 1970 unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read); 1971 mutex_lock(&tu->ioctl_lock); 1972 spin_lock_irq(&tu->qlock); 1973 while ((long)count - result >= unit) { 1974 while (!tu->qused) { 1975 wait_queue_entry_t wait; 1976 1977 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) { 1978 err = -EAGAIN; 1979 goto _error; 1980 } 1981 1982 set_current_state(TASK_INTERRUPTIBLE); 1983 init_waitqueue_entry(&wait, current); 1984 add_wait_queue(&tu->qchange_sleep, &wait); 1985 1986 spin_unlock_irq(&tu->qlock); 1987 mutex_unlock(&tu->ioctl_lock); 1988 schedule(); 1989 mutex_lock(&tu->ioctl_lock); 1990 spin_lock_irq(&tu->qlock); 1991 1992 remove_wait_queue(&tu->qchange_sleep, &wait); 1993 1994 if (tu->disconnected) { 1995 err = -ENODEV; 1996 goto _error; 1997 } 1998 if (signal_pending(current)) { 1999 err = -ERESTARTSYS; 2000 goto _error; 2001 } 2002 } 2003 2004 qhead = tu->qhead++; 2005 tu->qhead %= tu->queue_size; 2006 tu->qused--; 2007 spin_unlock_irq(&tu->qlock); 2008 2009 if (tu->tread) { 2010 if (copy_to_user(buffer, &tu->tqueue[qhead], 2011 sizeof(struct snd_timer_tread))) 2012 err = -EFAULT; 2013 } else { 2014 if (copy_to_user(buffer, &tu->queue[qhead], 2015 sizeof(struct snd_timer_read))) 2016 err = -EFAULT; 2017 } 2018 2019 spin_lock_irq(&tu->qlock); 2020 if (err < 0) 2021 goto _error; 2022 result += unit; 2023 buffer += unit; 2024 } 2025 _error: 2026 spin_unlock_irq(&tu->qlock); 2027 mutex_unlock(&tu->ioctl_lock); 2028 return result > 0 ? result : err; 2029 } 2030 2031 static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait) 2032 { 2033 unsigned int mask; 2034 struct snd_timer_user *tu; 2035 2036 tu = file->private_data; 2037 2038 poll_wait(file, &tu->qchange_sleep, wait); 2039 2040 mask = 0; 2041 spin_lock_irq(&tu->qlock); 2042 if (tu->qused) 2043 mask |= POLLIN | POLLRDNORM; 2044 if (tu->disconnected) 2045 mask |= POLLERR; 2046 spin_unlock_irq(&tu->qlock); 2047 2048 return mask; 2049 } 2050 2051 #ifdef CONFIG_COMPAT 2052 #include "timer_compat.c" 2053 #else 2054 #define snd_timer_user_ioctl_compat NULL 2055 #endif 2056 2057 static const struct file_operations snd_timer_f_ops = 2058 { 2059 .owner = THIS_MODULE, 2060 .read = snd_timer_user_read, 2061 .open = snd_timer_user_open, 2062 .release = snd_timer_user_release, 2063 .llseek = no_llseek, 2064 .poll = snd_timer_user_poll, 2065 .unlocked_ioctl = snd_timer_user_ioctl, 2066 .compat_ioctl = snd_timer_user_ioctl_compat, 2067 .fasync = snd_timer_user_fasync, 2068 }; 2069 2070 /* unregister the system timer */ 2071 static void snd_timer_free_all(void) 2072 { 2073 struct snd_timer *timer, *n; 2074 2075 list_for_each_entry_safe(timer, n, &snd_timer_list, device_list) 2076 snd_timer_free(timer); 2077 } 2078 2079 static struct device timer_dev; 2080 2081 /* 2082 * ENTRY functions 2083 */ 2084 2085 static int __init alsa_timer_init(void) 2086 { 2087 int err; 2088 2089 snd_device_initialize(&timer_dev, NULL); 2090 dev_set_name(&timer_dev, "timer"); 2091 2092 #ifdef SNDRV_OSS_INFO_DEV_TIMERS 2093 snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1, 2094 "system timer"); 2095 #endif 2096 2097 err = snd_timer_register_system(); 2098 if (err < 0) { 2099 pr_err("ALSA: unable to register system timer (%i)\n", err); 2100 goto put_timer; 2101 } 2102 2103 err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0, 2104 &snd_timer_f_ops, NULL, &timer_dev); 2105 if (err < 0) { 2106 pr_err("ALSA: unable to register timer device (%i)\n", err); 2107 snd_timer_free_all(); 2108 goto put_timer; 2109 } 2110 2111 snd_timer_proc_init(); 2112 return 0; 2113 2114 put_timer: 2115 put_device(&timer_dev); 2116 return err; 2117 } 2118 2119 static void __exit alsa_timer_exit(void) 2120 { 2121 snd_unregister_device(&timer_dev); 2122 snd_timer_free_all(); 2123 put_device(&timer_dev); 2124 snd_timer_proc_done(); 2125 #ifdef SNDRV_OSS_INFO_DEV_TIMERS 2126 snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1); 2127 #endif 2128 } 2129 2130 module_init(alsa_timer_init) 2131 module_exit(alsa_timer_exit) 2132