linux/sound/core/timer.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  Timers abstract layer
   4 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   5 */
   6
   7#include <linux/delay.h>
   8#include <linux/init.h>
   9#include <linux/slab.h>
  10#include <linux/time.h>
  11#include <linux/mutex.h>
  12#include <linux/device.h>
  13#include <linux/module.h>
  14#include <linux/string.h>
  15#include <linux/sched/signal.h>
  16#include <sound/core.h>
  17#include <sound/timer.h>
  18#include <sound/control.h>
  19#include <sound/info.h>
  20#include <sound/minors.h>
  21#include <sound/initval.h>
  22#include <linux/kmod.h>
  23
  24/* internal flags */
  25#define SNDRV_TIMER_IFLG_PAUSED         0x00010000
  26#define SNDRV_TIMER_IFLG_DEAD           0x00020000
  27
  28#if IS_ENABLED(CONFIG_SND_HRTIMER)
  29#define DEFAULT_TIMER_LIMIT 4
  30#else
  31#define DEFAULT_TIMER_LIMIT 1
  32#endif
  33
  34static int timer_limit = DEFAULT_TIMER_LIMIT;
  35static int timer_tstamp_monotonic = 1;
  36MODULE_AUTHOR("Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>");
  37MODULE_DESCRIPTION("ALSA timer interface");
  38MODULE_LICENSE("GPL");
  39module_param(timer_limit, int, 0444);
  40MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
  41module_param(timer_tstamp_monotonic, int, 0444);
  42MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
  43
  44MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
  45MODULE_ALIAS("devname:snd/timer");
  46
  47struct snd_timer_user {
  48        struct snd_timer_instance *timeri;
  49        int tread;              /* enhanced read with timestamps and events */
  50        unsigned long ticks;
  51        unsigned long overrun;
  52        int qhead;
  53        int qtail;
  54        int qused;
  55        int queue_size;
  56        bool disconnected;
  57        struct snd_timer_read *queue;
  58        struct snd_timer_tread *tqueue;
  59        spinlock_t qlock;
  60        unsigned long last_resolution;
  61        unsigned int filter;
  62        struct timespec tstamp;         /* trigger tstamp */
  63        wait_queue_head_t qchange_sleep;
  64        struct fasync_struct *fasync;
  65        struct mutex ioctl_lock;
  66};
  67
  68/* list of timers */
  69static LIST_HEAD(snd_timer_list);
  70
  71/* list of slave instances */
  72static LIST_HEAD(snd_timer_slave_list);
  73
  74/* lock for slave active lists */
  75static DEFINE_SPINLOCK(slave_active_lock);
  76
  77static DEFINE_MUTEX(register_mutex);
  78
  79static int snd_timer_free(struct snd_timer *timer);
  80static int snd_timer_dev_free(struct snd_device *device);
  81static int snd_timer_dev_register(struct snd_device *device);
  82static int snd_timer_dev_disconnect(struct snd_device *device);
  83
  84static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
  85
  86/*
  87 * create a timer instance with the given owner string.
  88 * when timer is not NULL, increments the module counter
  89 */
  90static struct snd_timer_instance *snd_timer_instance_new(char *owner,
  91                                                         struct snd_timer *timer)
  92{
  93        struct snd_timer_instance *timeri;
  94        timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
  95        if (timeri == NULL)
  96                return NULL;
  97        timeri->owner = kstrdup(owner, GFP_KERNEL);
  98        if (! timeri->owner) {
  99                kfree(timeri);
 100                return NULL;
 101        }
 102        INIT_LIST_HEAD(&timeri->open_list);
 103        INIT_LIST_HEAD(&timeri->active_list);
 104        INIT_LIST_HEAD(&timeri->ack_list);
 105        INIT_LIST_HEAD(&timeri->slave_list_head);
 106        INIT_LIST_HEAD(&timeri->slave_active_head);
 107
 108        timeri->timer = timer;
 109        if (timer && !try_module_get(timer->module)) {
 110                kfree(timeri->owner);
 111                kfree(timeri);
 112                return NULL;
 113        }
 114
 115        return timeri;
 116}
 117
 118/*
 119 * find a timer instance from the given timer id
 120 */
 121static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
 122{
 123        struct snd_timer *timer = NULL;
 124
 125        list_for_each_entry(timer, &snd_timer_list, device_list) {
 126                if (timer->tmr_class != tid->dev_class)
 127                        continue;
 128                if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
 129                     timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
 130                    (timer->card == NULL ||
 131                     timer->card->number != tid->card))
 132                        continue;
 133                if (timer->tmr_device != tid->device)
 134                        continue;
 135                if (timer->tmr_subdevice != tid->subdevice)
 136                        continue;
 137                return timer;
 138        }
 139        return NULL;
 140}
 141
 142#ifdef CONFIG_MODULES
 143
 144static void snd_timer_request(struct snd_timer_id *tid)
 145{
 146        switch (tid->dev_class) {
 147        case SNDRV_TIMER_CLASS_GLOBAL:
 148                if (tid->device < timer_limit)
 149                        request_module("snd-timer-%i", tid->device);
 150                break;
 151        case SNDRV_TIMER_CLASS_CARD:
 152        case SNDRV_TIMER_CLASS_PCM:
 153                if (tid->card < snd_ecards_limit)
 154                        request_module("snd-card-%i", tid->card);
 155                break;
 156        default:
 157                break;
 158        }
 159}
 160
 161#endif
 162
 163/*
 164 * look for a master instance matching with the slave id of the given slave.
 165 * when found, relink the open_link of the slave.
 166 *
 167 * call this with register_mutex down.
 168 */
 169static int snd_timer_check_slave(struct snd_timer_instance *slave)
 170{
 171        struct snd_timer *timer;
 172        struct snd_timer_instance *master;
 173
 174        /* FIXME: it's really dumb to look up all entries.. */
 175        list_for_each_entry(timer, &snd_timer_list, device_list) {
 176                list_for_each_entry(master, &timer->open_list_head, open_list) {
 177                        if (slave->slave_class == master->slave_class &&
 178                            slave->slave_id == master->slave_id) {
 179                                if (master->timer->num_instances >=
 180                                    master->timer->max_instances)
 181                                        return -EBUSY;
 182                                list_move_tail(&slave->open_list,
 183                                               &master->slave_list_head);
 184                                master->timer->num_instances++;
 185                                spin_lock_irq(&slave_active_lock);
 186                                slave->master = master;
 187                                slave->timer = master->timer;
 188                                spin_unlock_irq(&slave_active_lock);
 189                                return 0;
 190                        }
 191                }
 192        }
 193        return 0;
 194}
 195
 196/*
 197 * look for slave instances matching with the slave id of the given master.
 198 * when found, relink the open_link of slaves.
 199 *
 200 * call this with register_mutex down.
 201 */
 202static int snd_timer_check_master(struct snd_timer_instance *master)
 203{
 204        struct snd_timer_instance *slave, *tmp;
 205
 206        /* check all pending slaves */
 207        list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
 208                if (slave->slave_class == master->slave_class &&
 209                    slave->slave_id == master->slave_id) {
 210                        if (master->timer->num_instances >=
 211                            master->timer->max_instances)
 212                                return -EBUSY;
 213                        list_move_tail(&slave->open_list, &master->slave_list_head);
 214                        master->timer->num_instances++;
 215                        spin_lock_irq(&slave_active_lock);
 216                        spin_lock(&master->timer->lock);
 217                        slave->master = master;
 218                        slave->timer = master->timer;
 219                        if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
 220                                list_add_tail(&slave->active_list,
 221                                              &master->slave_active_head);
 222                        spin_unlock(&master->timer->lock);
 223                        spin_unlock_irq(&slave_active_lock);
 224                }
 225        }
 226        return 0;
 227}
 228
 229static int snd_timer_close_locked(struct snd_timer_instance *timeri);
 230
 231/*
 232 * open a timer instance
 233 * when opening a master, the slave id must be here given.
 234 */
 235int snd_timer_open(struct snd_timer_instance **ti,
 236                   char *owner, struct snd_timer_id *tid,
 237                   unsigned int slave_id)
 238{
 239        struct snd_timer *timer;
 240        struct snd_timer_instance *timeri = NULL;
 241        int err;
 242
 243        mutex_lock(&register_mutex);
 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                        err = -EINVAL;
 251                        goto unlock;
 252                }
 253                timeri = snd_timer_instance_new(owner, NULL);
 254                if (!timeri) {
 255                        err = -ENOMEM;
 256                        goto unlock;
 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                err = snd_timer_check_slave(timeri);
 263                if (err < 0) {
 264                        snd_timer_close_locked(timeri);
 265                        timeri = NULL;
 266                }
 267                goto unlock;
 268        }
 269
 270        /* open a master instance */
 271        timer = snd_timer_find(tid);
 272#ifdef CONFIG_MODULES
 273        if (!timer) {
 274                mutex_unlock(&register_mutex);
 275                snd_timer_request(tid);
 276                mutex_lock(&register_mutex);
 277                timer = snd_timer_find(tid);
 278        }
 279#endif
 280        if (!timer) {
 281                err = -ENODEV;
 282                goto unlock;
 283        }
 284        if (!list_empty(&timer->open_list_head)) {
 285                timeri = list_entry(timer->open_list_head.next,
 286                                    struct snd_timer_instance, open_list);
 287                if (timeri->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
 288                        err = -EBUSY;
 289                        timeri = NULL;
 290                        goto unlock;
 291                }
 292        }
 293        if (timer->num_instances >= timer->max_instances) {
 294                err = -EBUSY;
 295                goto unlock;
 296        }
 297        timeri = snd_timer_instance_new(owner, timer);
 298        if (!timeri) {
 299                err = -ENOMEM;
 300                goto unlock;
 301        }
 302        /* take a card refcount for safe disconnection */
 303        if (timer->card)
 304                get_device(&timer->card->card_dev);
 305        timeri->slave_class = tid->dev_sclass;
 306        timeri->slave_id = slave_id;
 307
 308        if (list_empty(&timer->open_list_head) && timer->hw.open) {
 309                err = timer->hw.open(timer);
 310                if (err) {
 311                        kfree(timeri->owner);
 312                        kfree(timeri);
 313                        timeri = NULL;
 314
 315                        if (timer->card)
 316                                put_device(&timer->card->card_dev);
 317                        module_put(timer->module);
 318                        goto unlock;
 319                }
 320        }
 321
 322        list_add_tail(&timeri->open_list, &timer->open_list_head);
 323        timer->num_instances++;
 324        err = snd_timer_check_master(timeri);
 325        if (err < 0) {
 326                snd_timer_close_locked(timeri);
 327                timeri = NULL;
 328        }
 329
 330 unlock:
 331        mutex_unlock(&register_mutex);
 332        *ti = timeri;
 333        return err;
 334}
 335EXPORT_SYMBOL(snd_timer_open);
 336
 337/*
 338 * close a timer instance
 339 * call this with register_mutex down.
 340 */
 341static int snd_timer_close_locked(struct snd_timer_instance *timeri)
 342{
 343        struct snd_timer *timer = timeri->timer;
 344        struct snd_timer_instance *slave, *tmp;
 345
 346        if (timer) {
 347                spin_lock_irq(&timer->lock);
 348                timeri->flags |= SNDRV_TIMER_IFLG_DEAD;
 349                spin_unlock_irq(&timer->lock);
 350        }
 351
 352        list_del(&timeri->open_list);
 353
 354        /* force to stop the timer */
 355        snd_timer_stop(timeri);
 356
 357        if (timer) {
 358                timer->num_instances--;
 359                /* wait, until the active callback is finished */
 360                spin_lock_irq(&timer->lock);
 361                while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 362                        spin_unlock_irq(&timer->lock);
 363                        udelay(10);
 364                        spin_lock_irq(&timer->lock);
 365                }
 366                spin_unlock_irq(&timer->lock);
 367
 368                /* remove slave links */
 369                spin_lock_irq(&slave_active_lock);
 370                spin_lock(&timer->lock);
 371                list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
 372                                         open_list) {
 373                        list_move_tail(&slave->open_list, &snd_timer_slave_list);
 374                        timer->num_instances--;
 375                        slave->master = NULL;
 376                        slave->timer = NULL;
 377                        list_del_init(&slave->ack_list);
 378                        list_del_init(&slave->active_list);
 379                }
 380                spin_unlock(&timer->lock);
 381                spin_unlock_irq(&slave_active_lock);
 382
 383                /* slave doesn't need to release timer resources below */
 384                if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 385                        timer = NULL;
 386        }
 387
 388        if (timeri->private_free)
 389                timeri->private_free(timeri);
 390        kfree(timeri->owner);
 391        kfree(timeri);
 392
 393        if (timer) {
 394                if (list_empty(&timer->open_list_head) && timer->hw.close)
 395                        timer->hw.close(timer);
 396                /* release a card refcount for safe disconnection */
 397                if (timer->card)
 398                        put_device(&timer->card->card_dev);
 399                module_put(timer->module);
 400        }
 401
 402        return 0;
 403}
 404
 405/*
 406 * close a timer instance
 407 */
 408int snd_timer_close(struct snd_timer_instance *timeri)
 409{
 410        int err;
 411
 412        if (snd_BUG_ON(!timeri))
 413                return -ENXIO;
 414
 415        mutex_lock(&register_mutex);
 416        err = snd_timer_close_locked(timeri);
 417        mutex_unlock(&register_mutex);
 418        return err;
 419}
 420EXPORT_SYMBOL(snd_timer_close);
 421
 422static unsigned long snd_timer_hw_resolution(struct snd_timer *timer)
 423{
 424        if (timer->hw.c_resolution)
 425                return timer->hw.c_resolution(timer);
 426        else
 427                return timer->hw.resolution;
 428}
 429
 430unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
 431{
 432        struct snd_timer * timer;
 433        unsigned long ret = 0;
 434        unsigned long flags;
 435
 436        if (timeri == NULL)
 437                return 0;
 438        timer = timeri->timer;
 439        if (timer) {
 440                spin_lock_irqsave(&timer->lock, flags);
 441                ret = snd_timer_hw_resolution(timer);
 442                spin_unlock_irqrestore(&timer->lock, flags);
 443        }
 444        return ret;
 445}
 446EXPORT_SYMBOL(snd_timer_resolution);
 447
 448static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
 449{
 450        struct snd_timer *timer = ti->timer;
 451        unsigned long resolution = 0;
 452        struct snd_timer_instance *ts;
 453        struct timespec tstamp;
 454
 455        if (timer_tstamp_monotonic)
 456                ktime_get_ts(&tstamp);
 457        else
 458                getnstimeofday(&tstamp);
 459        if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
 460                       event > SNDRV_TIMER_EVENT_PAUSE))
 461                return;
 462        if (timer &&
 463            (event == SNDRV_TIMER_EVENT_START ||
 464             event == SNDRV_TIMER_EVENT_CONTINUE))
 465                resolution = snd_timer_hw_resolution(timer);
 466        if (ti->ccallback)
 467                ti->ccallback(ti, event, &tstamp, resolution);
 468        if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
 469                return;
 470        if (timer == NULL)
 471                return;
 472        if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 473                return;
 474        list_for_each_entry(ts, &ti->slave_active_head, active_list)
 475                if (ts->ccallback)
 476                        ts->ccallback(ts, event + 100, &tstamp, resolution);
 477}
 478
 479/* start/continue a master timer */
 480static int snd_timer_start1(struct snd_timer_instance *timeri,
 481                            bool start, unsigned long ticks)
 482{
 483        struct snd_timer *timer;
 484        int result;
 485        unsigned long flags;
 486
 487        timer = timeri->timer;
 488        if (!timer)
 489                return -EINVAL;
 490
 491        spin_lock_irqsave(&timer->lock, flags);
 492        if (timeri->flags & SNDRV_TIMER_IFLG_DEAD) {
 493                result = -EINVAL;
 494                goto unlock;
 495        }
 496        if (timer->card && timer->card->shutdown) {
 497                result = -ENODEV;
 498                goto unlock;
 499        }
 500        if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 501                             SNDRV_TIMER_IFLG_START)) {
 502                result = -EBUSY;
 503                goto unlock;
 504        }
 505
 506        if (start)
 507                timeri->ticks = timeri->cticks = ticks;
 508        else if (!timeri->cticks)
 509                timeri->cticks = 1;
 510        timeri->pticks = 0;
 511
 512        list_move_tail(&timeri->active_list, &timer->active_list_head);
 513        if (timer->running) {
 514                if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 515                        goto __start_now;
 516                timer->flags |= SNDRV_TIMER_FLG_RESCHED;
 517                timeri->flags |= SNDRV_TIMER_IFLG_START;
 518                result = 1; /* delayed start */
 519        } else {
 520                if (start)
 521                        timer->sticks = ticks;
 522                timer->hw.start(timer);
 523              __start_now:
 524                timer->running++;
 525                timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 526                result = 0;
 527        }
 528        snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 529                          SNDRV_TIMER_EVENT_CONTINUE);
 530 unlock:
 531        spin_unlock_irqrestore(&timer->lock, flags);
 532        return result;
 533}
 534
 535/* start/continue a slave timer */
 536static int snd_timer_start_slave(struct snd_timer_instance *timeri,
 537                                 bool start)
 538{
 539        unsigned long flags;
 540        int err;
 541
 542        spin_lock_irqsave(&slave_active_lock, flags);
 543        if (timeri->flags & SNDRV_TIMER_IFLG_DEAD) {
 544                err = -EINVAL;
 545                goto unlock;
 546        }
 547        if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) {
 548                err = -EBUSY;
 549                goto unlock;
 550        }
 551        timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 552        if (timeri->master && timeri->timer) {
 553                spin_lock(&timeri->timer->lock);
 554                list_add_tail(&timeri->active_list,
 555                              &timeri->master->slave_active_head);
 556                snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 557                                  SNDRV_TIMER_EVENT_CONTINUE);
 558                spin_unlock(&timeri->timer->lock);
 559        }
 560        err = 1; /* delayed start */
 561 unlock:
 562        spin_unlock_irqrestore(&slave_active_lock, flags);
 563        return err;
 564}
 565
 566/* stop/pause a master timer */
 567static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
 568{
 569        struct snd_timer *timer;
 570        int result = 0;
 571        unsigned long flags;
 572
 573        timer = timeri->timer;
 574        if (!timer)
 575                return -EINVAL;
 576        spin_lock_irqsave(&timer->lock, flags);
 577        if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 578                               SNDRV_TIMER_IFLG_START))) {
 579                result = -EBUSY;
 580                goto unlock;
 581        }
 582        list_del_init(&timeri->ack_list);
 583        list_del_init(&timeri->active_list);
 584        if (timer->card && timer->card->shutdown)
 585                goto unlock;
 586        if (stop) {
 587                timeri->cticks = timeri->ticks;
 588                timeri->pticks = 0;
 589        }
 590        if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
 591            !(--timer->running)) {
 592                timer->hw.stop(timer);
 593                if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
 594                        timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 595                        snd_timer_reschedule(timer, 0);
 596                        if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
 597                                timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 598                                timer->hw.start(timer);
 599                        }
 600                }
 601        }
 602        timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
 603        if (stop)
 604                timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
 605        else
 606                timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
 607        snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 608                          SNDRV_TIMER_EVENT_PAUSE);
 609 unlock:
 610        spin_unlock_irqrestore(&timer->lock, flags);
 611        return result;
 612}
 613
 614/* stop/pause a slave timer */
 615static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
 616{
 617        unsigned long flags;
 618
 619        spin_lock_irqsave(&slave_active_lock, flags);
 620        if (!(timeri->flags & SNDRV_TIMER_IFLG_RUNNING)) {
 621                spin_unlock_irqrestore(&slave_active_lock, flags);
 622                return -EBUSY;
 623        }
 624        timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 625        if (timeri->timer) {
 626                spin_lock(&timeri->timer->lock);
 627                list_del_init(&timeri->ack_list);
 628                list_del_init(&timeri->active_list);
 629                snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 630                                  SNDRV_TIMER_EVENT_PAUSE);
 631                spin_unlock(&timeri->timer->lock);
 632        }
 633        spin_unlock_irqrestore(&slave_active_lock, flags);
 634        return 0;
 635}
 636
 637/*
 638 *  start the timer instance
 639 */
 640int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
 641{
 642        if (timeri == NULL || ticks < 1)
 643                return -EINVAL;
 644        if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 645                return snd_timer_start_slave(timeri, true);
 646        else
 647                return snd_timer_start1(timeri, true, ticks);
 648}
 649EXPORT_SYMBOL(snd_timer_start);
 650
 651/*
 652 * stop the timer instance.
 653 *
 654 * do not call this from the timer callback!
 655 */
 656int snd_timer_stop(struct snd_timer_instance *timeri)
 657{
 658        if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 659                return snd_timer_stop_slave(timeri, true);
 660        else
 661                return snd_timer_stop1(timeri, true);
 662}
 663EXPORT_SYMBOL(snd_timer_stop);
 664
 665/*
 666 * start again..  the tick is kept.
 667 */
 668int snd_timer_continue(struct snd_timer_instance *timeri)
 669{
 670        /* timer can continue only after pause */
 671        if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
 672                return -EINVAL;
 673
 674        if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 675                return snd_timer_start_slave(timeri, false);
 676        else
 677                return snd_timer_start1(timeri, false, 0);
 678}
 679EXPORT_SYMBOL(snd_timer_continue);
 680
 681/*
 682 * pause.. remember the ticks left
 683 */
 684int snd_timer_pause(struct snd_timer_instance * timeri)
 685{
 686        if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 687                return snd_timer_stop_slave(timeri, false);
 688        else
 689                return snd_timer_stop1(timeri, false);
 690}
 691EXPORT_SYMBOL(snd_timer_pause);
 692
 693/*
 694 * reschedule the timer
 695 *
 696 * start pending instances and check the scheduling ticks.
 697 * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
 698 */
 699static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
 700{
 701        struct snd_timer_instance *ti;
 702        unsigned long ticks = ~0UL;
 703
 704        list_for_each_entry(ti, &timer->active_list_head, active_list) {
 705                if (ti->flags & SNDRV_TIMER_IFLG_START) {
 706                        ti->flags &= ~SNDRV_TIMER_IFLG_START;
 707                        ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
 708                        timer->running++;
 709                }
 710                if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
 711                        if (ticks > ti->cticks)
 712                                ticks = ti->cticks;
 713                }
 714        }
 715        if (ticks == ~0UL) {
 716                timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 717                return;
 718        }
 719        if (ticks > timer->hw.ticks)
 720                ticks = timer->hw.ticks;
 721        if (ticks_left != ticks)
 722                timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 723        timer->sticks = ticks;
 724}
 725
 726/* call callbacks in timer ack list */
 727static void snd_timer_process_callbacks(struct snd_timer *timer,
 728                                        struct list_head *head)
 729{
 730        struct snd_timer_instance *ti;
 731        unsigned long resolution, ticks;
 732
 733        while (!list_empty(head)) {
 734                ti = list_first_entry(head, struct snd_timer_instance,
 735                                      ack_list);
 736
 737                /* remove from ack_list and make empty */
 738                list_del_init(&ti->ack_list);
 739
 740                if (!(ti->flags & SNDRV_TIMER_IFLG_DEAD)) {
 741                        ticks = ti->pticks;
 742                        ti->pticks = 0;
 743                        resolution = ti->resolution;
 744                        ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 745                        spin_unlock(&timer->lock);
 746                        if (ti->callback)
 747                                ti->callback(ti, resolution, ticks);
 748                        spin_lock(&timer->lock);
 749                        ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 750                }
 751        }
 752}
 753
 754/* clear pending instances from ack list */
 755static void snd_timer_clear_callbacks(struct snd_timer *timer,
 756                                      struct list_head *head)
 757{
 758        unsigned long flags;
 759
 760        spin_lock_irqsave(&timer->lock, flags);
 761        while (!list_empty(head))
 762                list_del_init(head->next);
 763        spin_unlock_irqrestore(&timer->lock, flags);
 764}
 765
 766/*
 767 * timer tasklet
 768 *
 769 */
 770static void snd_timer_tasklet(unsigned long arg)
 771{
 772        struct snd_timer *timer = (struct snd_timer *) arg;
 773        unsigned long flags;
 774
 775        if (timer->card && timer->card->shutdown) {
 776                snd_timer_clear_callbacks(timer, &timer->sack_list_head);
 777                return;
 778        }
 779
 780        spin_lock_irqsave(&timer->lock, flags);
 781        snd_timer_process_callbacks(timer, &timer->sack_list_head);
 782        spin_unlock_irqrestore(&timer->lock, flags);
 783}
 784
 785/*
 786 * timer interrupt
 787 *
 788 * ticks_left is usually equal to timer->sticks.
 789 *
 790 */
 791void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
 792{
 793        struct snd_timer_instance *ti, *ts, *tmp;
 794        unsigned long resolution;
 795        struct list_head *ack_list_head;
 796        unsigned long flags;
 797        int use_tasklet = 0;
 798
 799        if (timer == NULL)
 800                return;
 801
 802        if (timer->card && timer->card->shutdown) {
 803                snd_timer_clear_callbacks(timer, &timer->ack_list_head);
 804                return;
 805        }
 806
 807        spin_lock_irqsave(&timer->lock, flags);
 808
 809        /* remember the current resolution */
 810        resolution = snd_timer_hw_resolution(timer);
 811
 812        /* loop for all active instances
 813         * Here we cannot use list_for_each_entry because the active_list of a
 814         * processed instance is relinked to done_list_head before the callback
 815         * is called.
 816         */
 817        list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
 818                                 active_list) {
 819                if (ti->flags & SNDRV_TIMER_IFLG_DEAD)
 820                        continue;
 821                if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
 822                        continue;
 823                ti->pticks += ticks_left;
 824                ti->resolution = resolution;
 825                if (ti->cticks < ticks_left)
 826                        ti->cticks = 0;
 827                else
 828                        ti->cticks -= ticks_left;
 829                if (ti->cticks) /* not expired */
 830                        continue;
 831                if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
 832                        ti->cticks = ti->ticks;
 833                } else {
 834                        ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 835                        --timer->running;
 836                        list_del_init(&ti->active_list);
 837                }
 838                if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
 839                    (ti->flags & SNDRV_TIMER_IFLG_FAST))
 840                        ack_list_head = &timer->ack_list_head;
 841                else
 842                        ack_list_head = &timer->sack_list_head;
 843                if (list_empty(&ti->ack_list))
 844                        list_add_tail(&ti->ack_list, ack_list_head);
 845                list_for_each_entry(ts, &ti->slave_active_head, active_list) {
 846                        ts->pticks = ti->pticks;
 847                        ts->resolution = resolution;
 848                        if (list_empty(&ts->ack_list))
 849                                list_add_tail(&ts->ack_list, ack_list_head);
 850                }
 851        }
 852        if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
 853                snd_timer_reschedule(timer, timer->sticks);
 854        if (timer->running) {
 855                if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
 856                        timer->hw.stop(timer);
 857                        timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 858                }
 859                if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
 860                    (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
 861                        /* restart timer */
 862                        timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 863                        timer->hw.start(timer);
 864                }
 865        } else {
 866                timer->hw.stop(timer);
 867        }
 868
 869        /* now process all fast callbacks */
 870        snd_timer_process_callbacks(timer, &timer->ack_list_head);
 871
 872        /* do we have any slow callbacks? */
 873        use_tasklet = !list_empty(&timer->sack_list_head);
 874        spin_unlock_irqrestore(&timer->lock, flags);
 875
 876        if (use_tasklet)
 877                tasklet_schedule(&timer->task_queue);
 878}
 879EXPORT_SYMBOL(snd_timer_interrupt);
 880
 881/*
 882
 883 */
 884
 885int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
 886                  struct snd_timer **rtimer)
 887{
 888        struct snd_timer *timer;
 889        int err;
 890        static struct snd_device_ops ops = {
 891                .dev_free = snd_timer_dev_free,
 892                .dev_register = snd_timer_dev_register,
 893                .dev_disconnect = snd_timer_dev_disconnect,
 894        };
 895
 896        if (snd_BUG_ON(!tid))
 897                return -EINVAL;
 898        if (tid->dev_class == SNDRV_TIMER_CLASS_CARD ||
 899            tid->dev_class == SNDRV_TIMER_CLASS_PCM) {
 900                if (WARN_ON(!card))
 901                        return -EINVAL;
 902        }
 903        if (rtimer)
 904                *rtimer = NULL;
 905        timer = kzalloc(sizeof(*timer), GFP_KERNEL);
 906        if (!timer)
 907                return -ENOMEM;
 908        timer->tmr_class = tid->dev_class;
 909        timer->card = card;
 910        timer->tmr_device = tid->device;
 911        timer->tmr_subdevice = tid->subdevice;
 912        if (id)
 913                strlcpy(timer->id, id, sizeof(timer->id));
 914        timer->sticks = 1;
 915        INIT_LIST_HEAD(&timer->device_list);
 916        INIT_LIST_HEAD(&timer->open_list_head);
 917        INIT_LIST_HEAD(&timer->active_list_head);
 918        INIT_LIST_HEAD(&timer->ack_list_head);
 919        INIT_LIST_HEAD(&timer->sack_list_head);
 920        spin_lock_init(&timer->lock);
 921        tasklet_init(&timer->task_queue, snd_timer_tasklet,
 922                     (unsigned long)timer);
 923        timer->max_instances = 1000; /* default limit per timer */
 924        if (card != NULL) {
 925                timer->module = card->module;
 926                err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
 927                if (err < 0) {
 928                        snd_timer_free(timer);
 929                        return err;
 930                }
 931        }
 932        if (rtimer)
 933                *rtimer = timer;
 934        return 0;
 935}
 936EXPORT_SYMBOL(snd_timer_new);
 937
 938static int snd_timer_free(struct snd_timer *timer)
 939{
 940        if (!timer)
 941                return 0;
 942
 943        mutex_lock(&register_mutex);
 944        if (! list_empty(&timer->open_list_head)) {
 945                struct list_head *p, *n;
 946                struct snd_timer_instance *ti;
 947                pr_warn("ALSA: timer %p is busy?\n", timer);
 948                list_for_each_safe(p, n, &timer->open_list_head) {
 949                        list_del_init(p);
 950                        ti = list_entry(p, struct snd_timer_instance, open_list);
 951                        ti->timer = NULL;
 952                }
 953        }
 954        list_del(&timer->device_list);
 955        mutex_unlock(&register_mutex);
 956
 957        if (timer->private_free)
 958                timer->private_free(timer);
 959        kfree(timer);
 960        return 0;
 961}
 962
 963static int snd_timer_dev_free(struct snd_device *device)
 964{
 965        struct snd_timer *timer = device->device_data;
 966        return snd_timer_free(timer);
 967}
 968
 969static int snd_timer_dev_register(struct snd_device *dev)
 970{
 971        struct snd_timer *timer = dev->device_data;
 972        struct snd_timer *timer1;
 973
 974        if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
 975                return -ENXIO;
 976        if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
 977            !timer->hw.resolution && timer->hw.c_resolution == NULL)
 978                return -EINVAL;
 979
 980        mutex_lock(&register_mutex);
 981        list_for_each_entry(timer1, &snd_timer_list, device_list) {
 982                if (timer1->tmr_class > timer->tmr_class)
 983                        break;
 984                if (timer1->tmr_class < timer->tmr_class)
 985                        continue;
 986                if (timer1->card && timer->card) {
 987                        if (timer1->card->number > timer->card->number)
 988                                break;
 989                        if (timer1->card->number < timer->card->number)
 990                                continue;
 991                }
 992                if (timer1->tmr_device > timer->tmr_device)
 993                        break;
 994                if (timer1->tmr_device < timer->tmr_device)
 995                        continue;
 996                if (timer1->tmr_subdevice > timer->tmr_subdevice)
 997                        break;
 998                if (timer1->tmr_subdevice < timer->tmr_subdevice)
 999                        continue;
1000                /* conflicts.. */
1001                mutex_unlock(&register_mutex);
1002                return -EBUSY;
1003        }
1004        list_add_tail(&timer->device_list, &timer1->device_list);
1005        mutex_unlock(&register_mutex);
1006        return 0;
1007}
1008
1009static int snd_timer_dev_disconnect(struct snd_device *device)
1010{
1011        struct snd_timer *timer = device->device_data;
1012        struct snd_timer_instance *ti;
1013
1014        mutex_lock(&register_mutex);
1015        list_del_init(&timer->device_list);
1016        /* wake up pending sleepers */
1017        list_for_each_entry(ti, &timer->open_list_head, open_list) {
1018                if (ti->disconnect)
1019                        ti->disconnect(ti);
1020        }
1021        mutex_unlock(&register_mutex);
1022        return 0;
1023}
1024
1025void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstamp)
1026{
1027        unsigned long flags;
1028        unsigned long resolution = 0;
1029        struct snd_timer_instance *ti, *ts;
1030
1031        if (timer->card && timer->card->shutdown)
1032                return;
1033        if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
1034                return;
1035        if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
1036                       event > SNDRV_TIMER_EVENT_MRESUME))
1037                return;
1038        spin_lock_irqsave(&timer->lock, flags);
1039        if (event == SNDRV_TIMER_EVENT_MSTART ||
1040            event == SNDRV_TIMER_EVENT_MCONTINUE ||
1041            event == SNDRV_TIMER_EVENT_MRESUME)
1042                resolution = snd_timer_hw_resolution(timer);
1043        list_for_each_entry(ti, &timer->active_list_head, active_list) {
1044                if (ti->ccallback)
1045                        ti->ccallback(ti, event, tstamp, resolution);
1046                list_for_each_entry(ts, &ti->slave_active_head, active_list)
1047                        if (ts->ccallback)
1048                                ts->ccallback(ts, event, tstamp, resolution);
1049        }
1050        spin_unlock_irqrestore(&timer->lock, flags);
1051}
1052EXPORT_SYMBOL(snd_timer_notify);
1053
1054/*
1055 * exported functions for global timers
1056 */
1057int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
1058{
1059        struct snd_timer_id tid;
1060
1061        tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
1062        tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1063        tid.card = -1;
1064        tid.device = device;
1065        tid.subdevice = 0;
1066        return snd_timer_new(NULL, id, &tid, rtimer);
1067}
1068EXPORT_SYMBOL(snd_timer_global_new);
1069
1070int snd_timer_global_free(struct snd_timer *timer)
1071{
1072        return snd_timer_free(timer);
1073}
1074EXPORT_SYMBOL(snd_timer_global_free);
1075
1076int snd_timer_global_register(struct snd_timer *timer)
1077{
1078        struct snd_device dev;
1079
1080        memset(&dev, 0, sizeof(dev));
1081        dev.device_data = timer;
1082        return snd_timer_dev_register(&dev);
1083}
1084EXPORT_SYMBOL(snd_timer_global_register);
1085
1086/*
1087 *  System timer
1088 */
1089
1090struct snd_timer_system_private {
1091        struct timer_list tlist;
1092        struct snd_timer *snd_timer;
1093        unsigned long last_expires;
1094        unsigned long last_jiffies;
1095        unsigned long correction;
1096};
1097
1098static void snd_timer_s_function(struct timer_list *t)
1099{
1100        struct snd_timer_system_private *priv = from_timer(priv, t,
1101                                                                tlist);
1102        struct snd_timer *timer = priv->snd_timer;
1103        unsigned long jiff = jiffies;
1104        if (time_after(jiff, priv->last_expires))
1105                priv->correction += (long)jiff - (long)priv->last_expires;
1106        snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1107}
1108
1109static int snd_timer_s_start(struct snd_timer * timer)
1110{
1111        struct snd_timer_system_private *priv;
1112        unsigned long njiff;
1113
1114        priv = (struct snd_timer_system_private *) timer->private_data;
1115        njiff = (priv->last_jiffies = jiffies);
1116        if (priv->correction > timer->sticks - 1) {
1117                priv->correction -= timer->sticks - 1;
1118                njiff++;
1119        } else {
1120                njiff += timer->sticks - priv->correction;
1121                priv->correction = 0;
1122        }
1123        priv->last_expires = njiff;
1124        mod_timer(&priv->tlist, njiff);
1125        return 0;
1126}
1127
1128static int snd_timer_s_stop(struct snd_timer * timer)
1129{
1130        struct snd_timer_system_private *priv;
1131        unsigned long jiff;
1132
1133        priv = (struct snd_timer_system_private *) timer->private_data;
1134        del_timer(&priv->tlist);
1135        jiff = jiffies;
1136        if (time_before(jiff, priv->last_expires))
1137                timer->sticks = priv->last_expires - jiff;
1138        else
1139                timer->sticks = 1;
1140        priv->correction = 0;
1141        return 0;
1142}
1143
1144static int snd_timer_s_close(struct snd_timer *timer)
1145{
1146        struct snd_timer_system_private *priv;
1147
1148        priv = (struct snd_timer_system_private *)timer->private_data;
1149        del_timer_sync(&priv->tlist);
1150        return 0;
1151}
1152
1153static struct snd_timer_hardware snd_timer_system =
1154{
1155        .flags =        SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_TASKLET,
1156        .resolution =   1000000000L / HZ,
1157        .ticks =        10000000L,
1158        .close =        snd_timer_s_close,
1159        .start =        snd_timer_s_start,
1160        .stop =         snd_timer_s_stop
1161};
1162
1163static void snd_timer_free_system(struct snd_timer *timer)
1164{
1165        kfree(timer->private_data);
1166}
1167
1168static int snd_timer_register_system(void)
1169{
1170        struct snd_timer *timer;
1171        struct snd_timer_system_private *priv;
1172        int err;
1173
1174        err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1175        if (err < 0)
1176                return err;
1177        strcpy(timer->name, "system timer");
1178        timer->hw = snd_timer_system;
1179        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1180        if (priv == NULL) {
1181                snd_timer_free(timer);
1182                return -ENOMEM;
1183        }
1184        priv->snd_timer = timer;
1185        timer_setup(&priv->tlist, snd_timer_s_function, 0);
1186        timer->private_data = priv;
1187        timer->private_free = snd_timer_free_system;
1188        return snd_timer_global_register(timer);
1189}
1190
1191#ifdef CONFIG_SND_PROC_FS
1192/*
1193 *  Info interface
1194 */
1195
1196static void snd_timer_proc_read(struct snd_info_entry *entry,
1197                                struct snd_info_buffer *buffer)
1198{
1199        struct snd_timer *timer;
1200        struct snd_timer_instance *ti;
1201
1202        mutex_lock(&register_mutex);
1203        list_for_each_entry(timer, &snd_timer_list, device_list) {
1204                if (timer->card && timer->card->shutdown)
1205                        continue;
1206                switch (timer->tmr_class) {
1207                case SNDRV_TIMER_CLASS_GLOBAL:
1208                        snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1209                        break;
1210                case SNDRV_TIMER_CLASS_CARD:
1211                        snd_iprintf(buffer, "C%i-%i: ",
1212                                    timer->card->number, timer->tmr_device);
1213                        break;
1214                case SNDRV_TIMER_CLASS_PCM:
1215                        snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1216                                    timer->tmr_device, timer->tmr_subdevice);
1217                        break;
1218                default:
1219                        snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1220                                    timer->card ? timer->card->number : -1,
1221                                    timer->tmr_device, timer->tmr_subdevice);
1222                }
1223                snd_iprintf(buffer, "%s :", timer->name);
1224                if (timer->hw.resolution)
1225                        snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1226                                    timer->hw.resolution / 1000,
1227                                    timer->hw.resolution % 1000,
1228                                    timer->hw.ticks);
1229                if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1230                        snd_iprintf(buffer, " SLAVE");
1231                snd_iprintf(buffer, "\n");
1232                list_for_each_entry(ti, &timer->open_list_head, open_list)
1233                        snd_iprintf(buffer, "  Client %s : %s\n",
1234                                    ti->owner ? ti->owner : "unknown",
1235                                    ti->flags & (SNDRV_TIMER_IFLG_START |
1236                                                 SNDRV_TIMER_IFLG_RUNNING)
1237                                    ? "running" : "stopped");
1238        }
1239        mutex_unlock(&register_mutex);
1240}
1241
1242static struct snd_info_entry *snd_timer_proc_entry;
1243
1244static void __init snd_timer_proc_init(void)
1245{
1246        struct snd_info_entry *entry;
1247
1248        entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1249        if (entry != NULL) {
1250                entry->c.text.read = snd_timer_proc_read;
1251                if (snd_info_register(entry) < 0) {
1252                        snd_info_free_entry(entry);
1253                        entry = NULL;
1254                }
1255        }
1256        snd_timer_proc_entry = entry;
1257}
1258
1259static void __exit snd_timer_proc_done(void)
1260{
1261        snd_info_free_entry(snd_timer_proc_entry);
1262}
1263#else /* !CONFIG_SND_PROC_FS */
1264#define snd_timer_proc_init()
1265#define snd_timer_proc_done()
1266#endif
1267
1268/*
1269 *  USER SPACE interface
1270 */
1271
1272static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1273                                     unsigned long resolution,
1274                                     unsigned long ticks)
1275{
1276        struct snd_timer_user *tu = timeri->callback_data;
1277        struct snd_timer_read *r;
1278        int prev;
1279
1280        spin_lock(&tu->qlock);
1281        if (tu->qused > 0) {
1282                prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1283                r = &tu->queue[prev];
1284                if (r->resolution == resolution) {
1285                        r->ticks += ticks;
1286                        goto __wake;
1287                }
1288        }
1289        if (tu->qused >= tu->queue_size) {
1290                tu->overrun++;
1291        } else {
1292                r = &tu->queue[tu->qtail++];
1293                tu->qtail %= tu->queue_size;
1294                r->resolution = resolution;
1295                r->ticks = ticks;
1296                tu->qused++;
1297        }
1298      __wake:
1299        spin_unlock(&tu->qlock);
1300        kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1301        wake_up(&tu->qchange_sleep);
1302}
1303
1304static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1305                                            struct snd_timer_tread *tread)
1306{
1307        if (tu->qused >= tu->queue_size) {
1308                tu->overrun++;
1309        } else {
1310                memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1311                tu->qtail %= tu->queue_size;
1312                tu->qused++;
1313        }
1314}
1315
1316static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1317                                     int event,
1318                                     struct timespec *tstamp,
1319                                     unsigned long resolution)
1320{
1321        struct snd_timer_user *tu = timeri->callback_data;
1322        struct snd_timer_tread r1;
1323        unsigned long flags;
1324
1325        if (event >= SNDRV_TIMER_EVENT_START &&
1326            event <= SNDRV_TIMER_EVENT_PAUSE)
1327                tu->tstamp = *tstamp;
1328        if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1329                return;
1330        memset(&r1, 0, sizeof(r1));
1331        r1.event = event;
1332        r1.tstamp = *tstamp;
1333        r1.val = resolution;
1334        spin_lock_irqsave(&tu->qlock, flags);
1335        snd_timer_user_append_to_tqueue(tu, &r1);
1336        spin_unlock_irqrestore(&tu->qlock, flags);
1337        kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1338        wake_up(&tu->qchange_sleep);
1339}
1340
1341static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1342{
1343        struct snd_timer_user *tu = timeri->callback_data;
1344
1345        tu->disconnected = true;
1346        wake_up(&tu->qchange_sleep);
1347}
1348
1349static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1350                                      unsigned long resolution,
1351                                      unsigned long ticks)
1352{
1353        struct snd_timer_user *tu = timeri->callback_data;
1354        struct snd_timer_tread *r, r1;
1355        struct timespec tstamp;
1356        int prev, append = 0;
1357
1358        memset(&r1, 0, sizeof(r1));
1359        memset(&tstamp, 0, sizeof(tstamp));
1360        spin_lock(&tu->qlock);
1361        if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1362                           (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1363                spin_unlock(&tu->qlock);
1364                return;
1365        }
1366        if (tu->last_resolution != resolution || ticks > 0) {
1367                if (timer_tstamp_monotonic)
1368                        ktime_get_ts(&tstamp);
1369                else
1370                        getnstimeofday(&tstamp);
1371        }
1372        if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1373            tu->last_resolution != resolution) {
1374                r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1375                r1.tstamp = tstamp;
1376                r1.val = resolution;
1377                snd_timer_user_append_to_tqueue(tu, &r1);
1378                tu->last_resolution = resolution;
1379                append++;
1380        }
1381        if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1382                goto __wake;
1383        if (ticks == 0)
1384                goto __wake;
1385        if (tu->qused > 0) {
1386                prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1387                r = &tu->tqueue[prev];
1388                if (r->event == SNDRV_TIMER_EVENT_TICK) {
1389                        r->tstamp = tstamp;
1390                        r->val += ticks;
1391                        append++;
1392                        goto __wake;
1393                }
1394        }
1395        r1.event = SNDRV_TIMER_EVENT_TICK;
1396        r1.tstamp = tstamp;
1397        r1.val = ticks;
1398        snd_timer_user_append_to_tqueue(tu, &r1);
1399        append++;
1400      __wake:
1401        spin_unlock(&tu->qlock);
1402        if (append == 0)
1403                return;
1404        kill_fasync(&tu->fasync, SIGIO, POLL_IN);
1405        wake_up(&tu->qchange_sleep);
1406}
1407
1408static int realloc_user_queue(struct snd_timer_user *tu, int size)
1409{
1410        struct snd_timer_read *queue = NULL;
1411        struct snd_timer_tread *tqueue = NULL;
1412
1413        if (tu->tread) {
1414                tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL);
1415                if (!tqueue)
1416                        return -ENOMEM;
1417        } else {
1418                queue = kcalloc(size, sizeof(*queue), GFP_KERNEL);
1419                if (!queue)
1420                        return -ENOMEM;
1421        }
1422
1423        spin_lock_irq(&tu->qlock);
1424        kfree(tu->queue);
1425        kfree(tu->tqueue);
1426        tu->queue_size = size;
1427        tu->queue = queue;
1428        tu->tqueue = tqueue;
1429        tu->qhead = tu->qtail = tu->qused = 0;
1430        spin_unlock_irq(&tu->qlock);
1431
1432        return 0;
1433}
1434
1435static int snd_timer_user_open(struct inode *inode, struct file *file)
1436{
1437        struct snd_timer_user *tu;
1438        int err;
1439
1440        err = stream_open(inode, file);
1441        if (err < 0)
1442                return err;
1443
1444        tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1445        if (tu == NULL)
1446                return -ENOMEM;
1447        spin_lock_init(&tu->qlock);
1448        init_waitqueue_head(&tu->qchange_sleep);
1449        mutex_init(&tu->ioctl_lock);
1450        tu->ticks = 1;
1451        if (realloc_user_queue(tu, 128) < 0) {
1452                kfree(tu);
1453                return -ENOMEM;
1454        }
1455        file->private_data = tu;
1456        return 0;
1457}
1458
1459static int snd_timer_user_release(struct inode *inode, struct file *file)
1460{
1461        struct snd_timer_user *tu;
1462
1463        if (file->private_data) {
1464                tu = file->private_data;
1465                file->private_data = NULL;
1466                mutex_lock(&tu->ioctl_lock);
1467                if (tu->timeri)
1468                        snd_timer_close(tu->timeri);
1469                mutex_unlock(&tu->ioctl_lock);
1470                kfree(tu->queue);
1471                kfree(tu->tqueue);
1472                kfree(tu);
1473        }
1474        return 0;
1475}
1476
1477static void snd_timer_user_zero_id(struct snd_timer_id *id)
1478{
1479        id->dev_class = SNDRV_TIMER_CLASS_NONE;
1480        id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1481        id->card = -1;
1482        id->device = -1;
1483        id->subdevice = -1;
1484}
1485
1486static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1487{
1488        id->dev_class = timer->tmr_class;
1489        id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1490        id->card = timer->card ? timer->card->number : -1;
1491        id->device = timer->tmr_device;
1492        id->subdevice = timer->tmr_subdevice;
1493}
1494
1495static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1496{
1497        struct snd_timer_id id;
1498        struct snd_timer *timer;
1499        struct list_head *p;
1500
1501        if (copy_from_user(&id, _tid, sizeof(id)))
1502                return -EFAULT;
1503        mutex_lock(&register_mutex);
1504        if (id.dev_class < 0) {         /* first item */
1505                if (list_empty(&snd_timer_list))
1506                        snd_timer_user_zero_id(&id);
1507                else {
1508                        timer = list_entry(snd_timer_list.next,
1509                                           struct snd_timer, device_list);
1510                        snd_timer_user_copy_id(&id, timer);
1511                }
1512        } else {
1513                switch (id.dev_class) {
1514                case SNDRV_TIMER_CLASS_GLOBAL:
1515                        id.device = id.device < 0 ? 0 : id.device + 1;
1516                        list_for_each(p, &snd_timer_list) {
1517                                timer = list_entry(p, struct snd_timer, device_list);
1518                                if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1519                                        snd_timer_user_copy_id(&id, timer);
1520                                        break;
1521                                }
1522                                if (timer->tmr_device >= id.device) {
1523                                        snd_timer_user_copy_id(&id, timer);
1524                                        break;
1525                                }
1526                        }
1527                        if (p == &snd_timer_list)
1528                                snd_timer_user_zero_id(&id);
1529                        break;
1530                case SNDRV_TIMER_CLASS_CARD:
1531                case SNDRV_TIMER_CLASS_PCM:
1532                        if (id.card < 0) {
1533                                id.card = 0;
1534                        } else {
1535                                if (id.device < 0) {
1536                                        id.device = 0;
1537                                } else {
1538                                        if (id.subdevice < 0)
1539                                                id.subdevice = 0;
1540                                        else if (id.subdevice < INT_MAX)
1541                                                id.subdevice++;
1542                                }
1543                        }
1544                        list_for_each(p, &snd_timer_list) {
1545                                timer = list_entry(p, struct snd_timer, device_list);
1546                                if (timer->tmr_class > id.dev_class) {
1547                                        snd_timer_user_copy_id(&id, timer);
1548                                        break;
1549                                }
1550                                if (timer->tmr_class < id.dev_class)
1551                                        continue;
1552                                if (timer->card->number > id.card) {
1553                                        snd_timer_user_copy_id(&id, timer);
1554                                        break;
1555                                }
1556                                if (timer->card->number < id.card)
1557                                        continue;
1558                                if (timer->tmr_device > id.device) {
1559                                        snd_timer_user_copy_id(&id, timer);
1560                                        break;
1561                                }
1562                                if (timer->tmr_device < id.device)
1563                                        continue;
1564                                if (timer->tmr_subdevice > id.subdevice) {
1565                                        snd_timer_user_copy_id(&id, timer);
1566                                        break;
1567                                }
1568                                if (timer->tmr_subdevice < id.subdevice)
1569                                        continue;
1570                                snd_timer_user_copy_id(&id, timer);
1571                                break;
1572                        }
1573                        if (p == &snd_timer_list)
1574                                snd_timer_user_zero_id(&id);
1575                        break;
1576                default:
1577                        snd_timer_user_zero_id(&id);
1578                }
1579        }
1580        mutex_unlock(&register_mutex);
1581        if (copy_to_user(_tid, &id, sizeof(*_tid)))
1582                return -EFAULT;
1583        return 0;
1584}
1585
1586static int snd_timer_user_ginfo(struct file *file,
1587                                struct snd_timer_ginfo __user *_ginfo)
1588{
1589        struct snd_timer_ginfo *ginfo;
1590        struct snd_timer_id tid;
1591        struct snd_timer *t;
1592        struct list_head *p;
1593        int err = 0;
1594
1595        ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1596        if (IS_ERR(ginfo))
1597                return PTR_ERR(ginfo);
1598
1599        tid = ginfo->tid;
1600        memset(ginfo, 0, sizeof(*ginfo));
1601        ginfo->tid = tid;
1602        mutex_lock(&register_mutex);
1603        t = snd_timer_find(&tid);
1604        if (t != NULL) {
1605                ginfo->card = t->card ? t->card->number : -1;
1606                if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1607                        ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1608                strlcpy(ginfo->id, t->id, sizeof(ginfo->id));
1609                strlcpy(ginfo->name, t->name, sizeof(ginfo->name));
1610                ginfo->resolution = t->hw.resolution;
1611                if (t->hw.resolution_min > 0) {
1612                        ginfo->resolution_min = t->hw.resolution_min;
1613                        ginfo->resolution_max = t->hw.resolution_max;
1614                }
1615                list_for_each(p, &t->open_list_head) {
1616                        ginfo->clients++;
1617                }
1618        } else {
1619                err = -ENODEV;
1620        }
1621        mutex_unlock(&register_mutex);
1622        if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1623                err = -EFAULT;
1624        kfree(ginfo);
1625        return err;
1626}
1627
1628static int timer_set_gparams(struct snd_timer_gparams *gparams)
1629{
1630        struct snd_timer *t;
1631        int err;
1632
1633        mutex_lock(&register_mutex);
1634        t = snd_timer_find(&gparams->tid);
1635        if (!t) {
1636                err = -ENODEV;
1637                goto _error;
1638        }
1639        if (!list_empty(&t->open_list_head)) {
1640                err = -EBUSY;
1641                goto _error;
1642        }
1643        if (!t->hw.set_period) {
1644                err = -ENOSYS;
1645                goto _error;
1646        }
1647        err = t->hw.set_period(t, gparams->period_num, gparams->period_den);
1648_error:
1649        mutex_unlock(&register_mutex);
1650        return err;
1651}
1652
1653static int snd_timer_user_gparams(struct file *file,
1654                                  struct snd_timer_gparams __user *_gparams)
1655{
1656        struct snd_timer_gparams gparams;
1657
1658        if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1659                return -EFAULT;
1660        return timer_set_gparams(&gparams);
1661}
1662
1663static int snd_timer_user_gstatus(struct file *file,
1664                                  struct snd_timer_gstatus __user *_gstatus)
1665{
1666        struct snd_timer_gstatus gstatus;
1667        struct snd_timer_id tid;
1668        struct snd_timer *t;
1669        int err = 0;
1670
1671        if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1672                return -EFAULT;
1673        tid = gstatus.tid;
1674        memset(&gstatus, 0, sizeof(gstatus));
1675        gstatus.tid = tid;
1676        mutex_lock(&register_mutex);
1677        t = snd_timer_find(&tid);
1678        if (t != NULL) {
1679                spin_lock_irq(&t->lock);
1680                gstatus.resolution = snd_timer_hw_resolution(t);
1681                if (t->hw.precise_resolution) {
1682                        t->hw.precise_resolution(t, &gstatus.resolution_num,
1683                                                 &gstatus.resolution_den);
1684                } else {
1685                        gstatus.resolution_num = gstatus.resolution;
1686                        gstatus.resolution_den = 1000000000uL;
1687                }
1688                spin_unlock_irq(&t->lock);
1689        } else {
1690                err = -ENODEV;
1691        }
1692        mutex_unlock(&register_mutex);
1693        if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1694                err = -EFAULT;
1695        return err;
1696}
1697
1698static int snd_timer_user_tselect(struct file *file,
1699                                  struct snd_timer_select __user *_tselect)
1700{
1701        struct snd_timer_user *tu;
1702        struct snd_timer_select tselect;
1703        char str[32];
1704        int err = 0;
1705
1706        tu = file->private_data;
1707        if (tu->timeri) {
1708                snd_timer_close(tu->timeri);
1709                tu->timeri = NULL;
1710        }
1711        if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1712                err = -EFAULT;
1713                goto __err;
1714        }
1715        sprintf(str, "application %i", current->pid);
1716        if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1717                tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1718        err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid);
1719        if (err < 0)
1720                goto __err;
1721
1722        tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1723        tu->timeri->callback = tu->tread
1724                        ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1725        tu->timeri->ccallback = snd_timer_user_ccallback;
1726        tu->timeri->callback_data = (void *)tu;
1727        tu->timeri->disconnect = snd_timer_user_disconnect;
1728
1729      __err:
1730        return err;
1731}
1732
1733static int snd_timer_user_info(struct file *file,
1734                               struct snd_timer_info __user *_info)
1735{
1736        struct snd_timer_user *tu;
1737        struct snd_timer_info *info;
1738        struct snd_timer *t;
1739        int err = 0;
1740
1741        tu = file->private_data;
1742        if (!tu->timeri)
1743                return -EBADFD;
1744        t = tu->timeri->timer;
1745        if (!t)
1746                return -EBADFD;
1747
1748        info = kzalloc(sizeof(*info), GFP_KERNEL);
1749        if (! info)
1750                return -ENOMEM;
1751        info->card = t->card ? t->card->number : -1;
1752        if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1753                info->flags |= SNDRV_TIMER_FLG_SLAVE;
1754        strlcpy(info->id, t->id, sizeof(info->id));
1755        strlcpy(info->name, t->name, sizeof(info->name));
1756        info->resolution = t->hw.resolution;
1757        if (copy_to_user(_info, info, sizeof(*_info)))
1758                err = -EFAULT;
1759        kfree(info);
1760        return err;
1761}
1762
1763static int snd_timer_user_params(struct file *file,
1764                                 struct snd_timer_params __user *_params)
1765{
1766        struct snd_timer_user *tu;
1767        struct snd_timer_params params;
1768        struct snd_timer *t;
1769        int err;
1770
1771        tu = file->private_data;
1772        if (!tu->timeri)
1773                return -EBADFD;
1774        t = tu->timeri->timer;
1775        if (!t)
1776                return -EBADFD;
1777        if (copy_from_user(&params, _params, sizeof(params)))
1778                return -EFAULT;
1779        if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1780                u64 resolution;
1781
1782                if (params.ticks < 1) {
1783                        err = -EINVAL;
1784                        goto _end;
1785                }
1786
1787                /* Don't allow resolution less than 1ms */
1788                resolution = snd_timer_resolution(tu->timeri);
1789                resolution *= params.ticks;
1790                if (resolution < 1000000) {
1791                        err = -EINVAL;
1792                        goto _end;
1793                }
1794        }
1795        if (params.queue_size > 0 &&
1796            (params.queue_size < 32 || params.queue_size > 1024)) {
1797                err = -EINVAL;
1798                goto _end;
1799        }
1800        if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1801                              (1<<SNDRV_TIMER_EVENT_TICK)|
1802                              (1<<SNDRV_TIMER_EVENT_START)|
1803                              (1<<SNDRV_TIMER_EVENT_STOP)|
1804                              (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1805                              (1<<SNDRV_TIMER_EVENT_PAUSE)|
1806                              (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1807                              (1<<SNDRV_TIMER_EVENT_RESUME)|
1808                              (1<<SNDRV_TIMER_EVENT_MSTART)|
1809                              (1<<SNDRV_TIMER_EVENT_MSTOP)|
1810                              (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1811                              (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1812                              (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1813                              (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1814                err = -EINVAL;
1815                goto _end;
1816        }
1817        snd_timer_stop(tu->timeri);
1818        spin_lock_irq(&t->lock);
1819        tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1820                               SNDRV_TIMER_IFLG_EXCLUSIVE|
1821                               SNDRV_TIMER_IFLG_EARLY_EVENT);
1822        if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1823                tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1824        if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1825                tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1826        if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1827                tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1828        spin_unlock_irq(&t->lock);
1829        if (params.queue_size > 0 &&
1830            (unsigned int)tu->queue_size != params.queue_size) {
1831                err = realloc_user_queue(tu, params.queue_size);
1832                if (err < 0)
1833                        goto _end;
1834        }
1835        spin_lock_irq(&tu->qlock);
1836        tu->qhead = tu->qtail = tu->qused = 0;
1837        if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1838                if (tu->tread) {
1839                        struct snd_timer_tread tread;
1840                        memset(&tread, 0, sizeof(tread));
1841                        tread.event = SNDRV_TIMER_EVENT_EARLY;
1842                        tread.tstamp.tv_sec = 0;
1843                        tread.tstamp.tv_nsec = 0;
1844                        tread.val = 0;
1845                        snd_timer_user_append_to_tqueue(tu, &tread);
1846                } else {
1847                        struct snd_timer_read *r = &tu->queue[0];
1848                        r->resolution = 0;
1849                        r->ticks = 0;
1850                        tu->qused++;
1851                        tu->qtail++;
1852                }
1853        }
1854        tu->filter = params.filter;
1855        tu->ticks = params.ticks;
1856        spin_unlock_irq(&tu->qlock);
1857        err = 0;
1858 _end:
1859        if (copy_to_user(_params, &params, sizeof(params)))
1860                return -EFAULT;
1861        return err;
1862}
1863
1864static int snd_timer_user_status(struct file *file,
1865                                 struct snd_timer_status __user *_status)
1866{
1867        struct snd_timer_user *tu;
1868        struct snd_timer_status status;
1869
1870        tu = file->private_data;
1871        if (!tu->timeri)
1872                return -EBADFD;
1873        memset(&status, 0, sizeof(status));
1874        status.tstamp = tu->tstamp;
1875        status.resolution = snd_timer_resolution(tu->timeri);
1876        status.lost = tu->timeri->lost;
1877        status.overrun = tu->overrun;
1878        spin_lock_irq(&tu->qlock);
1879        status.queue = tu->qused;
1880        spin_unlock_irq(&tu->qlock);
1881        if (copy_to_user(_status, &status, sizeof(status)))
1882                return -EFAULT;
1883        return 0;
1884}
1885
1886static int snd_timer_user_start(struct file *file)
1887{
1888        int err;
1889        struct snd_timer_user *tu;
1890
1891        tu = file->private_data;
1892        if (!tu->timeri)
1893                return -EBADFD;
1894        snd_timer_stop(tu->timeri);
1895        tu->timeri->lost = 0;
1896        tu->last_resolution = 0;
1897        err = snd_timer_start(tu->timeri, tu->ticks);
1898        if (err < 0)
1899                return err;
1900        return 0;
1901}
1902
1903static int snd_timer_user_stop(struct file *file)
1904{
1905        int err;
1906        struct snd_timer_user *tu;
1907
1908        tu = file->private_data;
1909        if (!tu->timeri)
1910                return -EBADFD;
1911        err = snd_timer_stop(tu->timeri);
1912        if (err < 0)
1913                return err;
1914        return 0;
1915}
1916
1917static int snd_timer_user_continue(struct file *file)
1918{
1919        int err;
1920        struct snd_timer_user *tu;
1921
1922        tu = file->private_data;
1923        if (!tu->timeri)
1924                return -EBADFD;
1925        /* start timer instead of continue if it's not used before */
1926        if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
1927                return snd_timer_user_start(file);
1928        tu->timeri->lost = 0;
1929        err = snd_timer_continue(tu->timeri);
1930        if (err < 0)
1931                return err;
1932        return 0;
1933}
1934
1935static int snd_timer_user_pause(struct file *file)
1936{
1937        int err;
1938        struct snd_timer_user *tu;
1939
1940        tu = file->private_data;
1941        if (!tu->timeri)
1942                return -EBADFD;
1943        err = snd_timer_pause(tu->timeri);
1944        if (err < 0)
1945                return err;
1946        return 0;
1947}
1948
1949enum {
1950        SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
1951        SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
1952        SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
1953        SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
1954};
1955
1956static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
1957                                 unsigned long arg)
1958{
1959        struct snd_timer_user *tu;
1960        void __user *argp = (void __user *)arg;
1961        int __user *p = argp;
1962
1963        tu = file->private_data;
1964        switch (cmd) {
1965        case SNDRV_TIMER_IOCTL_PVERSION:
1966                return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
1967        case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
1968                return snd_timer_user_next_device(argp);
1969        case SNDRV_TIMER_IOCTL_TREAD:
1970        {
1971                int xarg, old_tread;
1972
1973                if (tu->timeri) /* too late */
1974                        return -EBUSY;
1975                if (get_user(xarg, p))
1976                        return -EFAULT;
1977                old_tread = tu->tread;
1978                tu->tread = xarg ? 1 : 0;
1979                if (tu->tread != old_tread &&
1980                    realloc_user_queue(tu, tu->queue_size) < 0) {
1981                        tu->tread = old_tread;
1982                        return -ENOMEM;
1983                }
1984                return 0;
1985        }
1986        case SNDRV_TIMER_IOCTL_GINFO:
1987                return snd_timer_user_ginfo(file, argp);
1988        case SNDRV_TIMER_IOCTL_GPARAMS:
1989                return snd_timer_user_gparams(file, argp);
1990        case SNDRV_TIMER_IOCTL_GSTATUS:
1991                return snd_timer_user_gstatus(file, argp);
1992        case SNDRV_TIMER_IOCTL_SELECT:
1993                return snd_timer_user_tselect(file, argp);
1994        case SNDRV_TIMER_IOCTL_INFO:
1995                return snd_timer_user_info(file, argp);
1996        case SNDRV_TIMER_IOCTL_PARAMS:
1997                return snd_timer_user_params(file, argp);
1998        case SNDRV_TIMER_IOCTL_STATUS:
1999                return snd_timer_user_status(file, argp);
2000        case SNDRV_TIMER_IOCTL_START:
2001        case SNDRV_TIMER_IOCTL_START_OLD:
2002                return snd_timer_user_start(file);
2003        case SNDRV_TIMER_IOCTL_STOP:
2004        case SNDRV_TIMER_IOCTL_STOP_OLD:
2005                return snd_timer_user_stop(file);
2006        case SNDRV_TIMER_IOCTL_CONTINUE:
2007        case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
2008                return snd_timer_user_continue(file);
2009        case SNDRV_TIMER_IOCTL_PAUSE:
2010        case SNDRV_TIMER_IOCTL_PAUSE_OLD:
2011                return snd_timer_user_pause(file);
2012        }
2013        return -ENOTTY;
2014}
2015
2016static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2017                                 unsigned long arg)
2018{
2019        struct snd_timer_user *tu = file->private_data;
2020        long ret;
2021
2022        mutex_lock(&tu->ioctl_lock);
2023        ret = __snd_timer_user_ioctl(file, cmd, arg);
2024        mutex_unlock(&tu->ioctl_lock);
2025        return ret;
2026}
2027
2028static int snd_timer_user_fasync(int fd, struct file * file, int on)
2029{
2030        struct snd_timer_user *tu;
2031
2032        tu = file->private_data;
2033        return fasync_helper(fd, file, on, &tu->fasync);
2034}
2035
2036static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2037                                   size_t count, loff_t *offset)
2038{
2039        struct snd_timer_user *tu;
2040        long result = 0, unit;
2041        int qhead;
2042        int err = 0;
2043
2044        tu = file->private_data;
2045        unit = tu->tread ? sizeof(struct snd_timer_tread) : sizeof(struct snd_timer_read);
2046        mutex_lock(&tu->ioctl_lock);
2047        spin_lock_irq(&tu->qlock);
2048        while ((long)count - result >= unit) {
2049                while (!tu->qused) {
2050                        wait_queue_entry_t wait;
2051
2052                        if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2053                                err = -EAGAIN;
2054                                goto _error;
2055                        }
2056
2057                        set_current_state(TASK_INTERRUPTIBLE);
2058                        init_waitqueue_entry(&wait, current);
2059                        add_wait_queue(&tu->qchange_sleep, &wait);
2060
2061                        spin_unlock_irq(&tu->qlock);
2062                        mutex_unlock(&tu->ioctl_lock);
2063                        schedule();
2064                        mutex_lock(&tu->ioctl_lock);
2065                        spin_lock_irq(&tu->qlock);
2066
2067                        remove_wait_queue(&tu->qchange_sleep, &wait);
2068
2069                        if (tu->disconnected) {
2070                                err = -ENODEV;
2071                                goto _error;
2072                        }
2073                        if (signal_pending(current)) {
2074                                err = -ERESTARTSYS;
2075                                goto _error;
2076                        }
2077                }
2078
2079                qhead = tu->qhead++;
2080                tu->qhead %= tu->queue_size;
2081                tu->qused--;
2082                spin_unlock_irq(&tu->qlock);
2083
2084                if (tu->tread) {
2085                        if (copy_to_user(buffer, &tu->tqueue[qhead],
2086                                         sizeof(struct snd_timer_tread)))
2087                                err = -EFAULT;
2088                } else {
2089                        if (copy_to_user(buffer, &tu->queue[qhead],
2090                                         sizeof(struct snd_timer_read)))
2091                                err = -EFAULT;
2092                }
2093
2094                spin_lock_irq(&tu->qlock);
2095                if (err < 0)
2096                        goto _error;
2097                result += unit;
2098                buffer += unit;
2099        }
2100 _error:
2101        spin_unlock_irq(&tu->qlock);
2102        mutex_unlock(&tu->ioctl_lock);
2103        return result > 0 ? result : err;
2104}
2105
2106static __poll_t snd_timer_user_poll(struct file *file, poll_table * wait)
2107{
2108        __poll_t mask;
2109        struct snd_timer_user *tu;
2110
2111        tu = file->private_data;
2112
2113        poll_wait(file, &tu->qchange_sleep, wait);
2114
2115        mask = 0;
2116        spin_lock_irq(&tu->qlock);
2117        if (tu->qused)
2118                mask |= EPOLLIN | EPOLLRDNORM;
2119        if (tu->disconnected)
2120                mask |= EPOLLERR;
2121        spin_unlock_irq(&tu->qlock);
2122
2123        return mask;
2124}
2125
2126#ifdef CONFIG_COMPAT
2127#include "timer_compat.c"
2128#else
2129#define snd_timer_user_ioctl_compat     NULL
2130#endif
2131
2132static const struct file_operations snd_timer_f_ops =
2133{
2134        .owner =        THIS_MODULE,
2135        .read =         snd_timer_user_read,
2136        .open =         snd_timer_user_open,
2137        .release =      snd_timer_user_release,
2138        .llseek =       no_llseek,
2139        .poll =         snd_timer_user_poll,
2140        .unlocked_ioctl =       snd_timer_user_ioctl,
2141        .compat_ioctl = snd_timer_user_ioctl_compat,
2142        .fasync =       snd_timer_user_fasync,
2143};
2144
2145/* unregister the system timer */
2146static void snd_timer_free_all(void)
2147{
2148        struct snd_timer *timer, *n;
2149
2150        list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2151                snd_timer_free(timer);
2152}
2153
2154static struct device timer_dev;
2155
2156/*
2157 *  ENTRY functions
2158 */
2159
2160static int __init alsa_timer_init(void)
2161{
2162        int err;
2163
2164        snd_device_initialize(&timer_dev, NULL);
2165        dev_set_name(&timer_dev, "timer");
2166
2167#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2168        snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2169                              "system timer");
2170#endif
2171
2172        err = snd_timer_register_system();
2173        if (err < 0) {
2174                pr_err("ALSA: unable to register system timer (%i)\n", err);
2175                goto put_timer;
2176        }
2177
2178        err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2179                                  &snd_timer_f_ops, NULL, &timer_dev);
2180        if (err < 0) {
2181                pr_err("ALSA: unable to register timer device (%i)\n", err);
2182                snd_timer_free_all();
2183                goto put_timer;
2184        }
2185
2186        snd_timer_proc_init();
2187        return 0;
2188
2189put_timer:
2190        put_device(&timer_dev);
2191        return err;
2192}
2193
2194static void __exit alsa_timer_exit(void)
2195{
2196        snd_unregister_device(&timer_dev);
2197        snd_timer_free_all();
2198        put_device(&timer_dev);
2199        snd_timer_proc_done();
2200#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2201        snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2202#endif
2203}
2204
2205module_init(alsa_timer_init)
2206module_exit(alsa_timer_exit)
2207