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
  47enum timer_tread_format {
  48	TREAD_FORMAT_NONE = 0,
  49	TREAD_FORMAT_TIME64,
  50	TREAD_FORMAT_TIME32,
  51};
  52
  53struct snd_timer_tread32 {
  54	int event;
  55	s32 tstamp_sec;
  56	s32 tstamp_nsec;
  57	unsigned int val;
  58};
  59
  60struct snd_timer_tread64 {
  61	int event;
  62	u8 pad1[4];
  63	s64 tstamp_sec;
  64	s64 tstamp_nsec;
  65	unsigned int val;
  66	u8 pad2[4];
  67};
  68
  69struct snd_timer_user {
  70	struct snd_timer_instance *timeri;
  71	int tread;		/* enhanced read with timestamps and events */
  72	unsigned long ticks;
  73	unsigned long overrun;
  74	int qhead;
  75	int qtail;
  76	int qused;
  77	int queue_size;
  78	bool disconnected;
  79	struct snd_timer_read *queue;
  80	struct snd_timer_tread64 *tqueue;
  81	spinlock_t qlock;
  82	unsigned long last_resolution;
  83	unsigned int filter;
  84	struct timespec64 tstamp;		/* trigger tstamp */
  85	wait_queue_head_t qchange_sleep;
  86	struct snd_fasync *fasync;
  87	struct mutex ioctl_lock;
  88};
  89
  90struct snd_timer_status32 {
  91	s32 tstamp_sec;			/* Timestamp - last update */
  92	s32 tstamp_nsec;
  93	unsigned int resolution;	/* current period resolution in ns */
  94	unsigned int lost;		/* counter of master tick lost */
  95	unsigned int overrun;		/* count of read queue overruns */
  96	unsigned int queue;		/* used queue size */
  97	unsigned char reserved[64];	/* reserved */
  98};
  99
 100#define SNDRV_TIMER_IOCTL_STATUS32	_IOR('T', 0x14, struct snd_timer_status32)
 101
 102struct snd_timer_status64 {
 103	s64 tstamp_sec;			/* Timestamp - last update */
 104	s64 tstamp_nsec;
 105	unsigned int resolution;	/* current period resolution in ns */
 106	unsigned int lost;		/* counter of master tick lost */
 107	unsigned int overrun;		/* count of read queue overruns */
 108	unsigned int queue;		/* used queue size */
 109	unsigned char reserved[64];	/* reserved */
 110};
 111
 112#define SNDRV_TIMER_IOCTL_STATUS64	_IOR('T', 0x14, struct snd_timer_status64)
 113
 114/* list of timers */
 115static LIST_HEAD(snd_timer_list);
 116
 117/* list of slave instances */
 118static LIST_HEAD(snd_timer_slave_list);
 119
 120/* lock for slave active lists */
 121static DEFINE_SPINLOCK(slave_active_lock);
 122
 123#define MAX_SLAVE_INSTANCES	1000
 124static int num_slaves;
 125
 126static DEFINE_MUTEX(register_mutex);
 127
 128static int snd_timer_free(struct snd_timer *timer);
 129static int snd_timer_dev_free(struct snd_device *device);
 130static int snd_timer_dev_register(struct snd_device *device);
 131static int snd_timer_dev_disconnect(struct snd_device *device);
 132
 133static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
 134
 135/*
 136 * create a timer instance with the given owner string.
 137 */
 138struct snd_timer_instance *snd_timer_instance_new(const char *owner)
 139{
 140	struct snd_timer_instance *timeri;
 141
 142	timeri = kzalloc(sizeof(*timeri), GFP_KERNEL);
 143	if (timeri == NULL)
 144		return NULL;
 145	timeri->owner = kstrdup(owner, GFP_KERNEL);
 146	if (! timeri->owner) {
 147		kfree(timeri);
 148		return NULL;
 149	}
 150	INIT_LIST_HEAD(&timeri->open_list);
 151	INIT_LIST_HEAD(&timeri->active_list);
 152	INIT_LIST_HEAD(&timeri->ack_list);
 153	INIT_LIST_HEAD(&timeri->slave_list_head);
 154	INIT_LIST_HEAD(&timeri->slave_active_head);
 155
 156	return timeri;
 157}
 158EXPORT_SYMBOL(snd_timer_instance_new);
 159
 160void snd_timer_instance_free(struct snd_timer_instance *timeri)
 161{
 162	if (timeri) {
 163		if (timeri->private_free)
 164			timeri->private_free(timeri);
 165		kfree(timeri->owner);
 166		kfree(timeri);
 167	}
 168}
 169EXPORT_SYMBOL(snd_timer_instance_free);
 170
 171/*
 172 * find a timer instance from the given timer id
 173 */
 174static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
 175{
 176	struct snd_timer *timer;
 177
 178	list_for_each_entry(timer, &snd_timer_list, device_list) {
 179		if (timer->tmr_class != tid->dev_class)
 180			continue;
 181		if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
 182		     timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
 183		    (timer->card == NULL ||
 184		     timer->card->number != tid->card))
 185			continue;
 186		if (timer->tmr_device != tid->device)
 187			continue;
 188		if (timer->tmr_subdevice != tid->subdevice)
 189			continue;
 190		return timer;
 191	}
 192	return NULL;
 193}
 194
 195#ifdef CONFIG_MODULES
 196
 197static void snd_timer_request(struct snd_timer_id *tid)
 198{
 199	switch (tid->dev_class) {
 200	case SNDRV_TIMER_CLASS_GLOBAL:
 201		if (tid->device < timer_limit)
 202			request_module("snd-timer-%i", tid->device);
 203		break;
 204	case SNDRV_TIMER_CLASS_CARD:
 205	case SNDRV_TIMER_CLASS_PCM:
 206		if (tid->card < snd_ecards_limit)
 207			request_module("snd-card-%i", tid->card);
 208		break;
 209	default:
 210		break;
 211	}
 212}
 213
 214#endif
 215
 216/* move the slave if it belongs to the master; return 1 if match */
 217static int check_matching_master_slave(struct snd_timer_instance *master,
 218				       struct snd_timer_instance *slave)
 219{
 220	if (slave->slave_class != master->slave_class ||
 221	    slave->slave_id != master->slave_id)
 222		return 0;
 223	if (master->timer->num_instances >= master->timer->max_instances)
 224		return -EBUSY;
 225	list_move_tail(&slave->open_list, &master->slave_list_head);
 226	master->timer->num_instances++;
 227	spin_lock_irq(&slave_active_lock);
 228	spin_lock(&master->timer->lock);
 229	slave->master = master;
 230	slave->timer = master->timer;
 231	if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
 232		list_add_tail(&slave->active_list, &master->slave_active_head);
 233	spin_unlock(&master->timer->lock);
 234	spin_unlock_irq(&slave_active_lock);
 235	return 1;
 236}
 237
 238/*
 239 * look for a master instance matching with the slave id of the given slave.
 240 * when found, relink the open_link of the slave.
 241 *
 242 * call this with register_mutex down.
 243 */
 244static int snd_timer_check_slave(struct snd_timer_instance *slave)
 245{
 246	struct snd_timer *timer;
 247	struct snd_timer_instance *master;
 248	int err = 0;
 249
 250	/* FIXME: it's really dumb to look up all entries.. */
 251	list_for_each_entry(timer, &snd_timer_list, device_list) {
 252		list_for_each_entry(master, &timer->open_list_head, open_list) {
 253			err = check_matching_master_slave(master, slave);
 254			if (err != 0) /* match found or error */
 255				goto out;
 256		}
 257	}
 258 out:
 259	return err < 0 ? err : 0;
 260}
 261
 262/*
 263 * look for slave instances matching with the slave id of the given master.
 264 * when found, relink the open_link of slaves.
 265 *
 266 * call this with register_mutex down.
 267 */
 268static int snd_timer_check_master(struct snd_timer_instance *master)
 269{
 270	struct snd_timer_instance *slave, *tmp;
 271	int err = 0;
 272
 273	/* check all pending slaves */
 274	list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
 275		err = check_matching_master_slave(master, slave);
 276		if (err < 0)
 277			break;
 278	}
 279	return err < 0 ? err : 0;
 280}
 281
 282static void snd_timer_close_locked(struct snd_timer_instance *timeri,
 283				   struct device **card_devp_to_put);
 284
 285/*
 286 * open a timer instance
 287 * when opening a master, the slave id must be here given.
 288 */
 289int snd_timer_open(struct snd_timer_instance *timeri,
 290		   struct snd_timer_id *tid,
 291		   unsigned int slave_id)
 292{
 293	struct snd_timer *timer;
 294	struct device *card_dev_to_put = NULL;
 295	int err;
 296
 297	mutex_lock(&register_mutex);
 298	if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
 299		/* open a slave instance */
 300		if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
 301		    tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
 302			pr_debug("ALSA: timer: invalid slave class %i\n",
 303				 tid->dev_sclass);
 304			err = -EINVAL;
 305			goto unlock;
 306		}
 307		if (num_slaves >= MAX_SLAVE_INSTANCES) {
 308			err = -EBUSY;
 309			goto unlock;
 310		}
 311		timeri->slave_class = tid->dev_sclass;
 312		timeri->slave_id = tid->device;
 313		timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
 314		list_add_tail(&timeri->open_list, &snd_timer_slave_list);
 315		num_slaves++;
 316		err = snd_timer_check_slave(timeri);
 317		goto list_added;
 318	}
 319
 320	/* open a master instance */
 321	timer = snd_timer_find(tid);
 322#ifdef CONFIG_MODULES
 323	if (!timer) {
 324		mutex_unlock(&register_mutex);
 325		snd_timer_request(tid);
 326		mutex_lock(&register_mutex);
 327		timer = snd_timer_find(tid);
 328	}
 329#endif
 330	if (!timer) {
 331		err = -ENODEV;
 332		goto unlock;
 333	}
 334	if (!list_empty(&timer->open_list_head)) {
 335		struct snd_timer_instance *t =
 336			list_entry(timer->open_list_head.next,
 337				    struct snd_timer_instance, open_list);
 338		if (t->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
 339			err = -EBUSY;
 340			goto unlock;
 341		}
 342	}
 343	if (timer->num_instances >= timer->max_instances) {
 344		err = -EBUSY;
 345		goto unlock;
 346	}
 347	if (!try_module_get(timer->module)) {
 348		err = -EBUSY;
 349		goto unlock;
 350	}
 351	/* take a card refcount for safe disconnection */
 352	if (timer->card) {
 353		get_device(&timer->card->card_dev);
 354		card_dev_to_put = &timer->card->card_dev;
 355	}
 356
 357	if (list_empty(&timer->open_list_head) && timer->hw.open) {
 358		err = timer->hw.open(timer);
 359		if (err) {
 360			module_put(timer->module);
 361			goto unlock;
 362		}
 363	}
 364
 365	timeri->timer = timer;
 366	timeri->slave_class = tid->dev_sclass;
 367	timeri->slave_id = slave_id;
 368
 369	list_add_tail(&timeri->open_list, &timer->open_list_head);
 370	timer->num_instances++;
 371	err = snd_timer_check_master(timeri);
 372list_added:
 373	if (err < 0)
 374		snd_timer_close_locked(timeri, &card_dev_to_put);
 375
 376 unlock:
 377	mutex_unlock(&register_mutex);
 378	/* put_device() is called after unlock for avoiding deadlock */
 379	if (err < 0 && card_dev_to_put)
 380		put_device(card_dev_to_put);
 381	return err;
 382}
 383EXPORT_SYMBOL(snd_timer_open);
 384
 385/*
 386 * close a timer instance
 387 * call this with register_mutex down.
 388 */
 389static void snd_timer_close_locked(struct snd_timer_instance *timeri,
 390				   struct device **card_devp_to_put)
 391{
 392	struct snd_timer *timer = timeri->timer;
 393	struct snd_timer_instance *slave, *tmp;
 394
 395	if (timer) {
 396		spin_lock_irq(&timer->lock);
 397		timeri->flags |= SNDRV_TIMER_IFLG_DEAD;
 398		spin_unlock_irq(&timer->lock);
 399	}
 400
 401	if (!list_empty(&timeri->open_list)) {
 402		list_del_init(&timeri->open_list);
 403		if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 404			num_slaves--;
 405	}
 406
 407	/* force to stop the timer */
 408	snd_timer_stop(timeri);
 409
 410	if (timer) {
 411		timer->num_instances--;
 412		/* wait, until the active callback is finished */
 413		spin_lock_irq(&timer->lock);
 414		while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) {
 415			spin_unlock_irq(&timer->lock);
 416			udelay(10);
 417			spin_lock_irq(&timer->lock);
 418		}
 419		spin_unlock_irq(&timer->lock);
 420
 421		/* remove slave links */
 422		spin_lock_irq(&slave_active_lock);
 423		spin_lock(&timer->lock);
 424		timeri->timer = NULL;
 425		list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
 426					 open_list) {
 427			list_move_tail(&slave->open_list, &snd_timer_slave_list);
 428			timer->num_instances--;
 429			slave->master = NULL;
 430			slave->timer = NULL;
 431			list_del_init(&slave->ack_list);
 432			list_del_init(&slave->active_list);
 433		}
 434		spin_unlock(&timer->lock);
 435		spin_unlock_irq(&slave_active_lock);
 436
 437		/* slave doesn't need to release timer resources below */
 438		if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 439			timer = NULL;
 440	}
 441
 442	if (timer) {
 443		if (list_empty(&timer->open_list_head) && timer->hw.close)
 444			timer->hw.close(timer);
 445		/* release a card refcount for safe disconnection */
 446		if (timer->card)
 447			*card_devp_to_put = &timer->card->card_dev;
 448		module_put(timer->module);
 449	}
 450}
 451
 452/*
 453 * close a timer instance
 454 */
 455void snd_timer_close(struct snd_timer_instance *timeri)
 456{
 457	struct device *card_dev_to_put = NULL;
 458
 459	if (snd_BUG_ON(!timeri))
 460		return;
 461
 462	mutex_lock(&register_mutex);
 463	snd_timer_close_locked(timeri, &card_dev_to_put);
 464	mutex_unlock(&register_mutex);
 465	/* put_device() is called after unlock for avoiding deadlock */
 466	if (card_dev_to_put)
 467		put_device(card_dev_to_put);
 468}
 469EXPORT_SYMBOL(snd_timer_close);
 470
 471static unsigned long snd_timer_hw_resolution(struct snd_timer *timer)
 472{
 473	if (timer->hw.c_resolution)
 474		return timer->hw.c_resolution(timer);
 475	else
 476		return timer->hw.resolution;
 477}
 478
 479unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
 480{
 481	struct snd_timer * timer;
 482	unsigned long ret = 0;
 483	unsigned long flags;
 484
 485	if (timeri == NULL)
 486		return 0;
 487	timer = timeri->timer;
 488	if (timer) {
 489		spin_lock_irqsave(&timer->lock, flags);
 490		ret = snd_timer_hw_resolution(timer);
 491		spin_unlock_irqrestore(&timer->lock, flags);
 492	}
 493	return ret;
 494}
 495EXPORT_SYMBOL(snd_timer_resolution);
 496
 497static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
 498{
 499	struct snd_timer *timer = ti->timer;
 500	unsigned long resolution = 0;
 501	struct snd_timer_instance *ts;
 502	struct timespec64 tstamp;
 503
 504	if (timer_tstamp_monotonic)
 505		ktime_get_ts64(&tstamp);
 506	else
 507		ktime_get_real_ts64(&tstamp);
 508	if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
 509		       event > SNDRV_TIMER_EVENT_PAUSE))
 510		return;
 511	if (timer &&
 512	    (event == SNDRV_TIMER_EVENT_START ||
 513	     event == SNDRV_TIMER_EVENT_CONTINUE))
 514		resolution = snd_timer_hw_resolution(timer);
 515	if (ti->ccallback)
 516		ti->ccallback(ti, event, &tstamp, resolution);
 517	if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
 518		return;
 519	if (timer == NULL)
 520		return;
 521	if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 522		return;
 523	event += 10; /* convert to SNDRV_TIMER_EVENT_MXXX */
 524	list_for_each_entry(ts, &ti->slave_active_head, active_list)
 525		if (ts->ccallback)
 526			ts->ccallback(ts, event, &tstamp, resolution);
 527}
 528
 529/* start/continue a master timer */
 530static int snd_timer_start1(struct snd_timer_instance *timeri,
 531			    bool start, unsigned long ticks)
 532{
 533	struct snd_timer *timer;
 534	int result;
 535	unsigned long flags;
 536
 537	timer = timeri->timer;
 538	if (!timer)
 539		return -EINVAL;
 540
 541	spin_lock_irqsave(&timer->lock, flags);
 542	if (timeri->flags & SNDRV_TIMER_IFLG_DEAD) {
 543		result = -EINVAL;
 544		goto unlock;
 545	}
 546	if (timer->card && timer->card->shutdown) {
 547		result = -ENODEV;
 548		goto unlock;
 549	}
 550	if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 551			     SNDRV_TIMER_IFLG_START)) {
 552		result = -EBUSY;
 553		goto unlock;
 554	}
 555
 556	if (start)
 557		timeri->ticks = timeri->cticks = ticks;
 558	else if (!timeri->cticks)
 559		timeri->cticks = 1;
 560	timeri->pticks = 0;
 561
 562	list_move_tail(&timeri->active_list, &timer->active_list_head);
 563	if (timer->running) {
 564		if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
 565			goto __start_now;
 566		timer->flags |= SNDRV_TIMER_FLG_RESCHED;
 567		timeri->flags |= SNDRV_TIMER_IFLG_START;
 568		result = 1; /* delayed start */
 569	} else {
 570		if (start)
 571			timer->sticks = ticks;
 572		timer->hw.start(timer);
 573	      __start_now:
 574		timer->running++;
 575		timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 576		result = 0;
 577	}
 578	snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 579			  SNDRV_TIMER_EVENT_CONTINUE);
 580 unlock:
 581	spin_unlock_irqrestore(&timer->lock, flags);
 582	return result;
 583}
 584
 585/* start/continue a slave timer */
 586static int snd_timer_start_slave(struct snd_timer_instance *timeri,
 587				 bool start)
 588{
 589	unsigned long flags;
 590	int err;
 591
 592	spin_lock_irqsave(&slave_active_lock, flags);
 593	if (timeri->flags & SNDRV_TIMER_IFLG_DEAD) {
 594		err = -EINVAL;
 595		goto unlock;
 596	}
 597	if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING) {
 598		err = -EBUSY;
 599		goto unlock;
 600	}
 601	timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
 602	if (timeri->master && timeri->timer) {
 603		spin_lock(&timeri->timer->lock);
 604		list_add_tail(&timeri->active_list,
 605			      &timeri->master->slave_active_head);
 606		snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
 607				  SNDRV_TIMER_EVENT_CONTINUE);
 608		spin_unlock(&timeri->timer->lock);
 609	}
 610	err = 1; /* delayed start */
 611 unlock:
 612	spin_unlock_irqrestore(&slave_active_lock, flags);
 613	return err;
 614}
 615
 616/* stop/pause a master timer */
 617static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
 618{
 619	struct snd_timer *timer;
 620	int result = 0;
 621	unsigned long flags;
 622
 623	timer = timeri->timer;
 624	if (!timer)
 625		return -EINVAL;
 626	spin_lock_irqsave(&timer->lock, flags);
 627	list_del_init(&timeri->ack_list);
 628	list_del_init(&timeri->active_list);
 629	if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
 630			       SNDRV_TIMER_IFLG_START))) {
 631		result = -EBUSY;
 632		goto unlock;
 633	}
 
 
 634	if (timer->card && timer->card->shutdown)
 635		goto unlock;
 636	if (stop) {
 637		timeri->cticks = timeri->ticks;
 638		timeri->pticks = 0;
 639	}
 640	if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
 641	    !(--timer->running)) {
 642		timer->hw.stop(timer);
 643		if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
 644			timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 645			snd_timer_reschedule(timer, 0);
 646			if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
 647				timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 648				timer->hw.start(timer);
 649			}
 650		}
 651	}
 652	timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
 653	if (stop)
 654		timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
 655	else
 656		timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
 657	snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 658			  SNDRV_TIMER_EVENT_PAUSE);
 659 unlock:
 660	spin_unlock_irqrestore(&timer->lock, flags);
 661	return result;
 662}
 663
 664/* stop/pause a slave timer */
 665static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
 666{
 667	unsigned long flags;
 668	bool running;
 669
 670	spin_lock_irqsave(&slave_active_lock, flags);
 671	running = timeri->flags & SNDRV_TIMER_IFLG_RUNNING;
 
 
 
 672	timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 673	if (timeri->timer) {
 674		spin_lock(&timeri->timer->lock);
 675		list_del_init(&timeri->ack_list);
 676		list_del_init(&timeri->active_list);
 677		if (running)
 678			snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
 679					  SNDRV_TIMER_EVENT_PAUSE);
 680		spin_unlock(&timeri->timer->lock);
 681	}
 682	spin_unlock_irqrestore(&slave_active_lock, flags);
 683	return running ? 0 : -EBUSY;
 684}
 685
 686/*
 687 *  start the timer instance
 688 */
 689int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
 690{
 691	if (timeri == NULL || ticks < 1)
 692		return -EINVAL;
 693	if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 694		return snd_timer_start_slave(timeri, true);
 695	else
 696		return snd_timer_start1(timeri, true, ticks);
 697}
 698EXPORT_SYMBOL(snd_timer_start);
 699
 700/*
 701 * stop the timer instance.
 702 *
 703 * do not call this from the timer callback!
 704 */
 705int snd_timer_stop(struct snd_timer_instance *timeri)
 706{
 707	if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 708		return snd_timer_stop_slave(timeri, true);
 709	else
 710		return snd_timer_stop1(timeri, true);
 711}
 712EXPORT_SYMBOL(snd_timer_stop);
 713
 714/*
 715 * start again..  the tick is kept.
 716 */
 717int snd_timer_continue(struct snd_timer_instance *timeri)
 718{
 719	/* timer can continue only after pause */
 720	if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
 721		return -EINVAL;
 722
 723	if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 724		return snd_timer_start_slave(timeri, false);
 725	else
 726		return snd_timer_start1(timeri, false, 0);
 727}
 728EXPORT_SYMBOL(snd_timer_continue);
 729
 730/*
 731 * pause.. remember the ticks left
 732 */
 733int snd_timer_pause(struct snd_timer_instance * timeri)
 734{
 735	if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
 736		return snd_timer_stop_slave(timeri, false);
 737	else
 738		return snd_timer_stop1(timeri, false);
 739}
 740EXPORT_SYMBOL(snd_timer_pause);
 741
 742/*
 743 * reschedule the timer
 744 *
 745 * start pending instances and check the scheduling ticks.
 746 * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
 747 */
 748static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
 749{
 750	struct snd_timer_instance *ti;
 751	unsigned long ticks = ~0UL;
 752
 753	list_for_each_entry(ti, &timer->active_list_head, active_list) {
 754		if (ti->flags & SNDRV_TIMER_IFLG_START) {
 755			ti->flags &= ~SNDRV_TIMER_IFLG_START;
 756			ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
 757			timer->running++;
 758		}
 759		if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
 760			if (ticks > ti->cticks)
 761				ticks = ti->cticks;
 762		}
 763	}
 764	if (ticks == ~0UL) {
 765		timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
 766		return;
 767	}
 768	if (ticks > timer->hw.ticks)
 769		ticks = timer->hw.ticks;
 770	if (ticks_left != ticks)
 771		timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 772	timer->sticks = ticks;
 773}
 774
 775/* call callbacks in timer ack list */
 776static void snd_timer_process_callbacks(struct snd_timer *timer,
 777					struct list_head *head)
 778{
 779	struct snd_timer_instance *ti;
 780	unsigned long resolution, ticks;
 781
 782	while (!list_empty(head)) {
 783		ti = list_first_entry(head, struct snd_timer_instance,
 784				      ack_list);
 785
 786		/* remove from ack_list and make empty */
 787		list_del_init(&ti->ack_list);
 788
 789		if (!(ti->flags & SNDRV_TIMER_IFLG_DEAD)) {
 790			ticks = ti->pticks;
 791			ti->pticks = 0;
 792			resolution = ti->resolution;
 793			ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
 794			spin_unlock(&timer->lock);
 795			if (ti->callback)
 796				ti->callback(ti, resolution, ticks);
 797			spin_lock(&timer->lock);
 798			ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
 799		}
 800	}
 801}
 802
 803/* clear pending instances from ack list */
 804static void snd_timer_clear_callbacks(struct snd_timer *timer,
 805				      struct list_head *head)
 806{
 807	unsigned long flags;
 808
 809	spin_lock_irqsave(&timer->lock, flags);
 810	while (!list_empty(head))
 811		list_del_init(head->next);
 812	spin_unlock_irqrestore(&timer->lock, flags);
 813}
 814
 815/*
 816 * timer work
 817 *
 818 */
 819static void snd_timer_work(struct work_struct *work)
 820{
 821	struct snd_timer *timer = container_of(work, struct snd_timer, task_work);
 822	unsigned long flags;
 823
 824	if (timer->card && timer->card->shutdown) {
 825		snd_timer_clear_callbacks(timer, &timer->sack_list_head);
 826		return;
 827	}
 828
 829	spin_lock_irqsave(&timer->lock, flags);
 830	snd_timer_process_callbacks(timer, &timer->sack_list_head);
 831	spin_unlock_irqrestore(&timer->lock, flags);
 832}
 833
 834/*
 835 * timer interrupt
 836 *
 837 * ticks_left is usually equal to timer->sticks.
 838 *
 839 */
 840void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
 841{
 842	struct snd_timer_instance *ti, *ts, *tmp;
 843	unsigned long resolution;
 844	struct list_head *ack_list_head;
 845	unsigned long flags;
 846	bool use_work = false;
 847
 848	if (timer == NULL)
 849		return;
 850
 851	if (timer->card && timer->card->shutdown) {
 852		snd_timer_clear_callbacks(timer, &timer->ack_list_head);
 853		return;
 854	}
 855
 856	spin_lock_irqsave(&timer->lock, flags);
 857
 858	/* remember the current resolution */
 859	resolution = snd_timer_hw_resolution(timer);
 860
 861	/* loop for all active instances
 862	 * Here we cannot use list_for_each_entry because the active_list of a
 863	 * processed instance is relinked to done_list_head before the callback
 864	 * is called.
 865	 */
 866	list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
 867				 active_list) {
 868		if (ti->flags & SNDRV_TIMER_IFLG_DEAD)
 869			continue;
 870		if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
 871			continue;
 872		ti->pticks += ticks_left;
 873		ti->resolution = resolution;
 874		if (ti->cticks < ticks_left)
 875			ti->cticks = 0;
 876		else
 877			ti->cticks -= ticks_left;
 878		if (ti->cticks) /* not expired */
 879			continue;
 880		if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
 881			ti->cticks = ti->ticks;
 882		} else {
 883			ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
 884			--timer->running;
 885			list_del_init(&ti->active_list);
 886		}
 887		if ((timer->hw.flags & SNDRV_TIMER_HW_WORK) ||
 888		    (ti->flags & SNDRV_TIMER_IFLG_FAST))
 889			ack_list_head = &timer->ack_list_head;
 890		else
 891			ack_list_head = &timer->sack_list_head;
 892		if (list_empty(&ti->ack_list))
 893			list_add_tail(&ti->ack_list, ack_list_head);
 894		list_for_each_entry(ts, &ti->slave_active_head, active_list) {
 895			ts->pticks = ti->pticks;
 896			ts->resolution = resolution;
 897			if (list_empty(&ts->ack_list))
 898				list_add_tail(&ts->ack_list, ack_list_head);
 899		}
 900	}
 901	if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
 902		snd_timer_reschedule(timer, timer->sticks);
 903	if (timer->running) {
 904		if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
 905			timer->hw.stop(timer);
 906			timer->flags |= SNDRV_TIMER_FLG_CHANGE;
 907		}
 908		if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
 909		    (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
 910			/* restart timer */
 911			timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
 912			timer->hw.start(timer);
 913		}
 914	} else {
 915		timer->hw.stop(timer);
 916	}
 917
 918	/* now process all fast callbacks */
 919	snd_timer_process_callbacks(timer, &timer->ack_list_head);
 920
 921	/* do we have any slow callbacks? */
 922	use_work = !list_empty(&timer->sack_list_head);
 923	spin_unlock_irqrestore(&timer->lock, flags);
 924
 925	if (use_work)
 926		queue_work(system_highpri_wq, &timer->task_work);
 927}
 928EXPORT_SYMBOL(snd_timer_interrupt);
 929
 930/*
 931
 932 */
 933
 934int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
 935		  struct snd_timer **rtimer)
 936{
 937	struct snd_timer *timer;
 938	int err;
 939	static const struct snd_device_ops ops = {
 940		.dev_free = snd_timer_dev_free,
 941		.dev_register = snd_timer_dev_register,
 942		.dev_disconnect = snd_timer_dev_disconnect,
 943	};
 944
 945	if (snd_BUG_ON(!tid))
 946		return -EINVAL;
 947	if (tid->dev_class == SNDRV_TIMER_CLASS_CARD ||
 948	    tid->dev_class == SNDRV_TIMER_CLASS_PCM) {
 949		if (WARN_ON(!card))
 950			return -EINVAL;
 951	}
 952	if (rtimer)
 953		*rtimer = NULL;
 954	timer = kzalloc(sizeof(*timer), GFP_KERNEL);
 955	if (!timer)
 956		return -ENOMEM;
 957	timer->tmr_class = tid->dev_class;
 958	timer->card = card;
 959	timer->tmr_device = tid->device;
 960	timer->tmr_subdevice = tid->subdevice;
 961	if (id)
 962		strscpy(timer->id, id, sizeof(timer->id));
 963	timer->sticks = 1;
 964	INIT_LIST_HEAD(&timer->device_list);
 965	INIT_LIST_HEAD(&timer->open_list_head);
 966	INIT_LIST_HEAD(&timer->active_list_head);
 967	INIT_LIST_HEAD(&timer->ack_list_head);
 968	INIT_LIST_HEAD(&timer->sack_list_head);
 969	spin_lock_init(&timer->lock);
 970	INIT_WORK(&timer->task_work, snd_timer_work);
 971	timer->max_instances = 1000; /* default limit per timer */
 972	if (card != NULL) {
 973		timer->module = card->module;
 974		err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
 975		if (err < 0) {
 976			snd_timer_free(timer);
 977			return err;
 978		}
 979	}
 980	if (rtimer)
 981		*rtimer = timer;
 982	return 0;
 983}
 984EXPORT_SYMBOL(snd_timer_new);
 985
 986static int snd_timer_free(struct snd_timer *timer)
 987{
 988	if (!timer)
 989		return 0;
 990
 991	mutex_lock(&register_mutex);
 992	if (! list_empty(&timer->open_list_head)) {
 993		struct list_head *p, *n;
 994		struct snd_timer_instance *ti;
 995		pr_warn("ALSA: timer %p is busy?\n", timer);
 996		list_for_each_safe(p, n, &timer->open_list_head) {
 997			list_del_init(p);
 998			ti = list_entry(p, struct snd_timer_instance, open_list);
 999			ti->timer = NULL;
1000		}
1001	}
1002	list_del(&timer->device_list);
1003	mutex_unlock(&register_mutex);
1004
1005	if (timer->private_free)
1006		timer->private_free(timer);
1007	kfree(timer);
1008	return 0;
1009}
1010
1011static int snd_timer_dev_free(struct snd_device *device)
1012{
1013	struct snd_timer *timer = device->device_data;
1014	return snd_timer_free(timer);
1015}
1016
1017static int snd_timer_dev_register(struct snd_device *dev)
1018{
1019	struct snd_timer *timer = dev->device_data;
1020	struct snd_timer *timer1;
1021
1022	if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
1023		return -ENXIO;
1024	if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
1025	    !timer->hw.resolution && timer->hw.c_resolution == NULL)
1026	    	return -EINVAL;
1027
1028	mutex_lock(&register_mutex);
1029	list_for_each_entry(timer1, &snd_timer_list, device_list) {
1030		if (timer1->tmr_class > timer->tmr_class)
1031			break;
1032		if (timer1->tmr_class < timer->tmr_class)
1033			continue;
1034		if (timer1->card && timer->card) {
1035			if (timer1->card->number > timer->card->number)
1036				break;
1037			if (timer1->card->number < timer->card->number)
1038				continue;
1039		}
1040		if (timer1->tmr_device > timer->tmr_device)
1041			break;
1042		if (timer1->tmr_device < timer->tmr_device)
1043			continue;
1044		if (timer1->tmr_subdevice > timer->tmr_subdevice)
1045			break;
1046		if (timer1->tmr_subdevice < timer->tmr_subdevice)
1047			continue;
1048		/* conflicts.. */
1049		mutex_unlock(&register_mutex);
1050		return -EBUSY;
1051	}
1052	list_add_tail(&timer->device_list, &timer1->device_list);
1053	mutex_unlock(&register_mutex);
1054	return 0;
1055}
1056
1057static int snd_timer_dev_disconnect(struct snd_device *device)
1058{
1059	struct snd_timer *timer = device->device_data;
1060	struct snd_timer_instance *ti;
1061
1062	mutex_lock(&register_mutex);
1063	list_del_init(&timer->device_list);
1064	/* wake up pending sleepers */
1065	list_for_each_entry(ti, &timer->open_list_head, open_list) {
1066		if (ti->disconnect)
1067			ti->disconnect(ti);
1068	}
1069	mutex_unlock(&register_mutex);
1070	return 0;
1071}
1072
1073void snd_timer_notify(struct snd_timer *timer, int event, struct timespec64 *tstamp)
1074{
1075	unsigned long flags;
1076	unsigned long resolution = 0;
1077	struct snd_timer_instance *ti, *ts;
1078
1079	if (timer->card && timer->card->shutdown)
1080		return;
1081	if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
1082		return;
1083	if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
1084		       event > SNDRV_TIMER_EVENT_MRESUME))
1085		return;
1086	spin_lock_irqsave(&timer->lock, flags);
1087	if (event == SNDRV_TIMER_EVENT_MSTART ||
1088	    event == SNDRV_TIMER_EVENT_MCONTINUE ||
1089	    event == SNDRV_TIMER_EVENT_MRESUME)
1090		resolution = snd_timer_hw_resolution(timer);
1091	list_for_each_entry(ti, &timer->active_list_head, active_list) {
1092		if (ti->ccallback)
1093			ti->ccallback(ti, event, tstamp, resolution);
1094		list_for_each_entry(ts, &ti->slave_active_head, active_list)
1095			if (ts->ccallback)
1096				ts->ccallback(ts, event, tstamp, resolution);
1097	}
1098	spin_unlock_irqrestore(&timer->lock, flags);
1099}
1100EXPORT_SYMBOL(snd_timer_notify);
1101
1102/*
1103 * exported functions for global timers
1104 */
1105int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
1106{
1107	struct snd_timer_id tid;
1108
1109	tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
1110	tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1111	tid.card = -1;
1112	tid.device = device;
1113	tid.subdevice = 0;
1114	return snd_timer_new(NULL, id, &tid, rtimer);
1115}
1116EXPORT_SYMBOL(snd_timer_global_new);
1117
1118int snd_timer_global_free(struct snd_timer *timer)
1119{
1120	return snd_timer_free(timer);
1121}
1122EXPORT_SYMBOL(snd_timer_global_free);
1123
1124int snd_timer_global_register(struct snd_timer *timer)
1125{
1126	struct snd_device dev;
1127
1128	memset(&dev, 0, sizeof(dev));
1129	dev.device_data = timer;
1130	return snd_timer_dev_register(&dev);
1131}
1132EXPORT_SYMBOL(snd_timer_global_register);
1133
1134/*
1135 *  System timer
1136 */
1137
1138struct snd_timer_system_private {
1139	struct timer_list tlist;
1140	struct snd_timer *snd_timer;
1141	unsigned long last_expires;
1142	unsigned long last_jiffies;
1143	unsigned long correction;
1144};
1145
1146static void snd_timer_s_function(struct timer_list *t)
1147{
1148	struct snd_timer_system_private *priv = from_timer(priv, t,
1149								tlist);
1150	struct snd_timer *timer = priv->snd_timer;
1151	unsigned long jiff = jiffies;
1152	if (time_after(jiff, priv->last_expires))
1153		priv->correction += (long)jiff - (long)priv->last_expires;
1154	snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1155}
1156
1157static int snd_timer_s_start(struct snd_timer * timer)
1158{
1159	struct snd_timer_system_private *priv;
1160	unsigned long njiff;
1161
1162	priv = (struct snd_timer_system_private *) timer->private_data;
1163	njiff = (priv->last_jiffies = jiffies);
1164	if (priv->correction > timer->sticks - 1) {
1165		priv->correction -= timer->sticks - 1;
1166		njiff++;
1167	} else {
1168		njiff += timer->sticks - priv->correction;
1169		priv->correction = 0;
1170	}
1171	priv->last_expires = njiff;
1172	mod_timer(&priv->tlist, njiff);
1173	return 0;
1174}
1175
1176static int snd_timer_s_stop(struct snd_timer * timer)
1177{
1178	struct snd_timer_system_private *priv;
1179	unsigned long jiff;
1180
1181	priv = (struct snd_timer_system_private *) timer->private_data;
1182	del_timer(&priv->tlist);
1183	jiff = jiffies;
1184	if (time_before(jiff, priv->last_expires))
1185		timer->sticks = priv->last_expires - jiff;
1186	else
1187		timer->sticks = 1;
1188	priv->correction = 0;
1189	return 0;
1190}
1191
1192static int snd_timer_s_close(struct snd_timer *timer)
1193{
1194	struct snd_timer_system_private *priv;
1195
1196	priv = (struct snd_timer_system_private *)timer->private_data;
1197	del_timer_sync(&priv->tlist);
1198	return 0;
1199}
1200
1201static const struct snd_timer_hardware snd_timer_system =
1202{
1203	.flags =	SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_WORK,
1204	.resolution =	1000000000L / HZ,
1205	.ticks =	10000000L,
1206	.close =	snd_timer_s_close,
1207	.start =	snd_timer_s_start,
1208	.stop =		snd_timer_s_stop
1209};
1210
1211static void snd_timer_free_system(struct snd_timer *timer)
1212{
1213	kfree(timer->private_data);
1214}
1215
1216static int snd_timer_register_system(void)
1217{
1218	struct snd_timer *timer;
1219	struct snd_timer_system_private *priv;
1220	int err;
1221
1222	err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1223	if (err < 0)
1224		return err;
1225	strcpy(timer->name, "system timer");
1226	timer->hw = snd_timer_system;
1227	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
1228	if (priv == NULL) {
1229		snd_timer_free(timer);
1230		return -ENOMEM;
1231	}
1232	priv->snd_timer = timer;
1233	timer_setup(&priv->tlist, snd_timer_s_function, 0);
1234	timer->private_data = priv;
1235	timer->private_free = snd_timer_free_system;
1236	return snd_timer_global_register(timer);
1237}
1238
1239#ifdef CONFIG_SND_PROC_FS
1240/*
1241 *  Info interface
1242 */
1243
1244static void snd_timer_proc_read(struct snd_info_entry *entry,
1245				struct snd_info_buffer *buffer)
1246{
1247	struct snd_timer *timer;
1248	struct snd_timer_instance *ti;
1249
1250	mutex_lock(&register_mutex);
1251	list_for_each_entry(timer, &snd_timer_list, device_list) {
1252		if (timer->card && timer->card->shutdown)
1253			continue;
1254		switch (timer->tmr_class) {
1255		case SNDRV_TIMER_CLASS_GLOBAL:
1256			snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1257			break;
1258		case SNDRV_TIMER_CLASS_CARD:
1259			snd_iprintf(buffer, "C%i-%i: ",
1260				    timer->card->number, timer->tmr_device);
1261			break;
1262		case SNDRV_TIMER_CLASS_PCM:
1263			snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1264				    timer->tmr_device, timer->tmr_subdevice);
1265			break;
1266		default:
1267			snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1268				    timer->card ? timer->card->number : -1,
1269				    timer->tmr_device, timer->tmr_subdevice);
1270		}
1271		snd_iprintf(buffer, "%s :", timer->name);
1272		if (timer->hw.resolution)
1273			snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1274				    timer->hw.resolution / 1000,
1275				    timer->hw.resolution % 1000,
1276				    timer->hw.ticks);
1277		if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1278			snd_iprintf(buffer, " SLAVE");
1279		snd_iprintf(buffer, "\n");
1280		list_for_each_entry(ti, &timer->open_list_head, open_list)
1281			snd_iprintf(buffer, "  Client %s : %s\n",
1282				    ti->owner ? ti->owner : "unknown",
1283				    (ti->flags & (SNDRV_TIMER_IFLG_START |
1284						  SNDRV_TIMER_IFLG_RUNNING))
1285				    ? "running" : "stopped");
1286	}
1287	mutex_unlock(&register_mutex);
1288}
1289
1290static struct snd_info_entry *snd_timer_proc_entry;
1291
1292static void __init snd_timer_proc_init(void)
1293{
1294	struct snd_info_entry *entry;
1295
1296	entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1297	if (entry != NULL) {
1298		entry->c.text.read = snd_timer_proc_read;
1299		if (snd_info_register(entry) < 0) {
1300			snd_info_free_entry(entry);
1301			entry = NULL;
1302		}
1303	}
1304	snd_timer_proc_entry = entry;
1305}
1306
1307static void __exit snd_timer_proc_done(void)
1308{
1309	snd_info_free_entry(snd_timer_proc_entry);
1310}
1311#else /* !CONFIG_SND_PROC_FS */
1312#define snd_timer_proc_init()
1313#define snd_timer_proc_done()
1314#endif
1315
1316/*
1317 *  USER SPACE interface
1318 */
1319
1320static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1321				     unsigned long resolution,
1322				     unsigned long ticks)
1323{
1324	struct snd_timer_user *tu = timeri->callback_data;
1325	struct snd_timer_read *r;
1326	int prev;
1327
1328	spin_lock(&tu->qlock);
1329	if (tu->qused > 0) {
1330		prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1331		r = &tu->queue[prev];
1332		if (r->resolution == resolution) {
1333			r->ticks += ticks;
1334			goto __wake;
1335		}
1336	}
1337	if (tu->qused >= tu->queue_size) {
1338		tu->overrun++;
1339	} else {
1340		r = &tu->queue[tu->qtail++];
1341		tu->qtail %= tu->queue_size;
1342		r->resolution = resolution;
1343		r->ticks = ticks;
1344		tu->qused++;
1345	}
1346      __wake:
1347	spin_unlock(&tu->qlock);
1348	snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1349	wake_up(&tu->qchange_sleep);
1350}
1351
1352static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1353					    struct snd_timer_tread64 *tread)
1354{
1355	if (tu->qused >= tu->queue_size) {
1356		tu->overrun++;
1357	} else {
1358		memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1359		tu->qtail %= tu->queue_size;
1360		tu->qused++;
1361	}
1362}
1363
1364static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1365				     int event,
1366				     struct timespec64 *tstamp,
1367				     unsigned long resolution)
1368{
1369	struct snd_timer_user *tu = timeri->callback_data;
1370	struct snd_timer_tread64 r1;
1371	unsigned long flags;
1372
1373	if (event >= SNDRV_TIMER_EVENT_START &&
1374	    event <= SNDRV_TIMER_EVENT_PAUSE)
1375		tu->tstamp = *tstamp;
1376	if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1377		return;
1378	memset(&r1, 0, sizeof(r1));
1379	r1.event = event;
1380	r1.tstamp_sec = tstamp->tv_sec;
1381	r1.tstamp_nsec = tstamp->tv_nsec;
1382	r1.val = resolution;
1383	spin_lock_irqsave(&tu->qlock, flags);
1384	snd_timer_user_append_to_tqueue(tu, &r1);
1385	spin_unlock_irqrestore(&tu->qlock, flags);
1386	snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1387	wake_up(&tu->qchange_sleep);
1388}
1389
1390static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1391{
1392	struct snd_timer_user *tu = timeri->callback_data;
1393
1394	tu->disconnected = true;
1395	wake_up(&tu->qchange_sleep);
1396}
1397
1398static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1399				      unsigned long resolution,
1400				      unsigned long ticks)
1401{
1402	struct snd_timer_user *tu = timeri->callback_data;
1403	struct snd_timer_tread64 *r, r1;
1404	struct timespec64 tstamp;
1405	int prev, append = 0;
1406
1407	memset(&r1, 0, sizeof(r1));
1408	memset(&tstamp, 0, sizeof(tstamp));
1409	spin_lock(&tu->qlock);
1410	if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1411			   (1 << SNDRV_TIMER_EVENT_TICK))) == 0) {
1412		spin_unlock(&tu->qlock);
1413		return;
1414	}
1415	if (tu->last_resolution != resolution || ticks > 0) {
1416		if (timer_tstamp_monotonic)
1417			ktime_get_ts64(&tstamp);
1418		else
1419			ktime_get_real_ts64(&tstamp);
1420	}
1421	if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1422	    tu->last_resolution != resolution) {
1423		r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1424		r1.tstamp_sec = tstamp.tv_sec;
1425		r1.tstamp_nsec = tstamp.tv_nsec;
1426		r1.val = resolution;
1427		snd_timer_user_append_to_tqueue(tu, &r1);
1428		tu->last_resolution = resolution;
1429		append++;
1430	}
1431	if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1432		goto __wake;
1433	if (ticks == 0)
1434		goto __wake;
1435	if (tu->qused > 0) {
1436		prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1437		r = &tu->tqueue[prev];
1438		if (r->event == SNDRV_TIMER_EVENT_TICK) {
1439			r->tstamp_sec = tstamp.tv_sec;
1440			r->tstamp_nsec = tstamp.tv_nsec;
1441			r->val += ticks;
1442			append++;
1443			goto __wake;
1444		}
1445	}
1446	r1.event = SNDRV_TIMER_EVENT_TICK;
1447	r1.tstamp_sec = tstamp.tv_sec;
1448	r1.tstamp_nsec = tstamp.tv_nsec;
1449	r1.val = ticks;
1450	snd_timer_user_append_to_tqueue(tu, &r1);
1451	append++;
1452      __wake:
1453	spin_unlock(&tu->qlock);
1454	if (append == 0)
1455		return;
1456	snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1457	wake_up(&tu->qchange_sleep);
1458}
1459
1460static int realloc_user_queue(struct snd_timer_user *tu, int size)
1461{
1462	struct snd_timer_read *queue = NULL;
1463	struct snd_timer_tread64 *tqueue = NULL;
1464
1465	if (tu->tread) {
1466		tqueue = kcalloc(size, sizeof(*tqueue), GFP_KERNEL);
1467		if (!tqueue)
1468			return -ENOMEM;
1469	} else {
1470		queue = kcalloc(size, sizeof(*queue), GFP_KERNEL);
1471		if (!queue)
1472			return -ENOMEM;
1473	}
1474
1475	spin_lock_irq(&tu->qlock);
1476	kfree(tu->queue);
1477	kfree(tu->tqueue);
1478	tu->queue_size = size;
1479	tu->queue = queue;
1480	tu->tqueue = tqueue;
1481	tu->qhead = tu->qtail = tu->qused = 0;
1482	spin_unlock_irq(&tu->qlock);
1483
1484	return 0;
1485}
1486
1487static int snd_timer_user_open(struct inode *inode, struct file *file)
1488{
1489	struct snd_timer_user *tu;
1490	int err;
1491
1492	err = stream_open(inode, file);
1493	if (err < 0)
1494		return err;
1495
1496	tu = kzalloc(sizeof(*tu), GFP_KERNEL);
1497	if (tu == NULL)
1498		return -ENOMEM;
1499	spin_lock_init(&tu->qlock);
1500	init_waitqueue_head(&tu->qchange_sleep);
1501	mutex_init(&tu->ioctl_lock);
1502	tu->ticks = 1;
1503	if (realloc_user_queue(tu, 128) < 0) {
1504		kfree(tu);
1505		return -ENOMEM;
1506	}
1507	file->private_data = tu;
1508	return 0;
1509}
1510
1511static int snd_timer_user_release(struct inode *inode, struct file *file)
1512{
1513	struct snd_timer_user *tu;
1514
1515	if (file->private_data) {
1516		tu = file->private_data;
1517		file->private_data = NULL;
1518		mutex_lock(&tu->ioctl_lock);
1519		if (tu->timeri) {
1520			snd_timer_close(tu->timeri);
1521			snd_timer_instance_free(tu->timeri);
1522		}
1523		mutex_unlock(&tu->ioctl_lock);
1524		snd_fasync_free(tu->fasync);
1525		kfree(tu->queue);
1526		kfree(tu->tqueue);
1527		kfree(tu);
1528	}
1529	return 0;
1530}
1531
1532static void snd_timer_user_zero_id(struct snd_timer_id *id)
1533{
1534	id->dev_class = SNDRV_TIMER_CLASS_NONE;
1535	id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1536	id->card = -1;
1537	id->device = -1;
1538	id->subdevice = -1;
1539}
1540
1541static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1542{
1543	id->dev_class = timer->tmr_class;
1544	id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1545	id->card = timer->card ? timer->card->number : -1;
1546	id->device = timer->tmr_device;
1547	id->subdevice = timer->tmr_subdevice;
1548}
1549
1550static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1551{
1552	struct snd_timer_id id;
1553	struct snd_timer *timer;
1554	struct list_head *p;
1555
1556	if (copy_from_user(&id, _tid, sizeof(id)))
1557		return -EFAULT;
1558	mutex_lock(&register_mutex);
1559	if (id.dev_class < 0) {		/* first item */
1560		if (list_empty(&snd_timer_list))
1561			snd_timer_user_zero_id(&id);
1562		else {
1563			timer = list_entry(snd_timer_list.next,
1564					   struct snd_timer, device_list);
1565			snd_timer_user_copy_id(&id, timer);
1566		}
1567	} else {
1568		switch (id.dev_class) {
1569		case SNDRV_TIMER_CLASS_GLOBAL:
1570			id.device = id.device < 0 ? 0 : id.device + 1;
1571			list_for_each(p, &snd_timer_list) {
1572				timer = list_entry(p, struct snd_timer, device_list);
1573				if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1574					snd_timer_user_copy_id(&id, timer);
1575					break;
1576				}
1577				if (timer->tmr_device >= id.device) {
1578					snd_timer_user_copy_id(&id, timer);
1579					break;
1580				}
1581			}
1582			if (p == &snd_timer_list)
1583				snd_timer_user_zero_id(&id);
1584			break;
1585		case SNDRV_TIMER_CLASS_CARD:
1586		case SNDRV_TIMER_CLASS_PCM:
1587			if (id.card < 0) {
1588				id.card = 0;
1589			} else {
1590				if (id.device < 0) {
1591					id.device = 0;
1592				} else {
1593					if (id.subdevice < 0)
1594						id.subdevice = 0;
1595					else if (id.subdevice < INT_MAX)
1596						id.subdevice++;
1597				}
1598			}
1599			list_for_each(p, &snd_timer_list) {
1600				timer = list_entry(p, struct snd_timer, device_list);
1601				if (timer->tmr_class > id.dev_class) {
1602					snd_timer_user_copy_id(&id, timer);
1603					break;
1604				}
1605				if (timer->tmr_class < id.dev_class)
1606					continue;
1607				if (timer->card->number > id.card) {
1608					snd_timer_user_copy_id(&id, timer);
1609					break;
1610				}
1611				if (timer->card->number < id.card)
1612					continue;
1613				if (timer->tmr_device > id.device) {
1614					snd_timer_user_copy_id(&id, timer);
1615					break;
1616				}
1617				if (timer->tmr_device < id.device)
1618					continue;
1619				if (timer->tmr_subdevice > id.subdevice) {
1620					snd_timer_user_copy_id(&id, timer);
1621					break;
1622				}
1623				if (timer->tmr_subdevice < id.subdevice)
1624					continue;
1625				snd_timer_user_copy_id(&id, timer);
1626				break;
1627			}
1628			if (p == &snd_timer_list)
1629				snd_timer_user_zero_id(&id);
1630			break;
1631		default:
1632			snd_timer_user_zero_id(&id);
1633		}
1634	}
1635	mutex_unlock(&register_mutex);
1636	if (copy_to_user(_tid, &id, sizeof(*_tid)))
1637		return -EFAULT;
1638	return 0;
1639}
1640
1641static int snd_timer_user_ginfo(struct file *file,
1642				struct snd_timer_ginfo __user *_ginfo)
1643{
1644	struct snd_timer_ginfo *ginfo;
1645	struct snd_timer_id tid;
1646	struct snd_timer *t;
1647	struct list_head *p;
1648	int err = 0;
1649
1650	ginfo = memdup_user(_ginfo, sizeof(*ginfo));
1651	if (IS_ERR(ginfo))
1652		return PTR_ERR(ginfo);
1653
1654	tid = ginfo->tid;
1655	memset(ginfo, 0, sizeof(*ginfo));
1656	ginfo->tid = tid;
1657	mutex_lock(&register_mutex);
1658	t = snd_timer_find(&tid);
1659	if (t != NULL) {
1660		ginfo->card = t->card ? t->card->number : -1;
1661		if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1662			ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1663		strscpy(ginfo->id, t->id, sizeof(ginfo->id));
1664		strscpy(ginfo->name, t->name, sizeof(ginfo->name));
1665		ginfo->resolution = t->hw.resolution;
1666		if (t->hw.resolution_min > 0) {
1667			ginfo->resolution_min = t->hw.resolution_min;
1668			ginfo->resolution_max = t->hw.resolution_max;
1669		}
1670		list_for_each(p, &t->open_list_head) {
1671			ginfo->clients++;
1672		}
1673	} else {
1674		err = -ENODEV;
1675	}
1676	mutex_unlock(&register_mutex);
1677	if (err >= 0 && copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1678		err = -EFAULT;
1679	kfree(ginfo);
1680	return err;
1681}
1682
1683static int timer_set_gparams(struct snd_timer_gparams *gparams)
1684{
1685	struct snd_timer *t;
1686	int err;
1687
1688	mutex_lock(&register_mutex);
1689	t = snd_timer_find(&gparams->tid);
1690	if (!t) {
1691		err = -ENODEV;
1692		goto _error;
1693	}
1694	if (!list_empty(&t->open_list_head)) {
1695		err = -EBUSY;
1696		goto _error;
1697	}
1698	if (!t->hw.set_period) {
1699		err = -ENOSYS;
1700		goto _error;
1701	}
1702	err = t->hw.set_period(t, gparams->period_num, gparams->period_den);
1703_error:
1704	mutex_unlock(&register_mutex);
1705	return err;
1706}
1707
1708static int snd_timer_user_gparams(struct file *file,
1709				  struct snd_timer_gparams __user *_gparams)
1710{
1711	struct snd_timer_gparams gparams;
1712
1713	if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1714		return -EFAULT;
1715	return timer_set_gparams(&gparams);
1716}
1717
1718static int snd_timer_user_gstatus(struct file *file,
1719				  struct snd_timer_gstatus __user *_gstatus)
1720{
1721	struct snd_timer_gstatus gstatus;
1722	struct snd_timer_id tid;
1723	struct snd_timer *t;
1724	int err = 0;
1725
1726	if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1727		return -EFAULT;
1728	tid = gstatus.tid;
1729	memset(&gstatus, 0, sizeof(gstatus));
1730	gstatus.tid = tid;
1731	mutex_lock(&register_mutex);
1732	t = snd_timer_find(&tid);
1733	if (t != NULL) {
1734		spin_lock_irq(&t->lock);
1735		gstatus.resolution = snd_timer_hw_resolution(t);
1736		if (t->hw.precise_resolution) {
1737			t->hw.precise_resolution(t, &gstatus.resolution_num,
1738						 &gstatus.resolution_den);
1739		} else {
1740			gstatus.resolution_num = gstatus.resolution;
1741			gstatus.resolution_den = 1000000000uL;
1742		}
1743		spin_unlock_irq(&t->lock);
1744	} else {
1745		err = -ENODEV;
1746	}
1747	mutex_unlock(&register_mutex);
1748	if (err >= 0 && copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1749		err = -EFAULT;
1750	return err;
1751}
1752
1753static int snd_timer_user_tselect(struct file *file,
1754				  struct snd_timer_select __user *_tselect)
1755{
1756	struct snd_timer_user *tu;
1757	struct snd_timer_select tselect;
1758	char str[32];
1759	int err = 0;
1760
1761	tu = file->private_data;
1762	if (tu->timeri) {
1763		snd_timer_close(tu->timeri);
1764		snd_timer_instance_free(tu->timeri);
1765		tu->timeri = NULL;
1766	}
1767	if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1768		err = -EFAULT;
1769		goto __err;
1770	}
1771	sprintf(str, "application %i", current->pid);
1772	if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1773		tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1774	tu->timeri = snd_timer_instance_new(str);
1775	if (!tu->timeri) {
1776		err = -ENOMEM;
1777		goto __err;
1778	}
1779
1780	tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1781	tu->timeri->callback = tu->tread
1782			? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1783	tu->timeri->ccallback = snd_timer_user_ccallback;
1784	tu->timeri->callback_data = (void *)tu;
1785	tu->timeri->disconnect = snd_timer_user_disconnect;
1786
1787	err = snd_timer_open(tu->timeri, &tselect.id, current->pid);
1788	if (err < 0) {
1789		snd_timer_instance_free(tu->timeri);
1790		tu->timeri = NULL;
1791	}
1792
1793      __err:
1794	return err;
1795}
1796
1797static int snd_timer_user_info(struct file *file,
1798			       struct snd_timer_info __user *_info)
1799{
1800	struct snd_timer_user *tu;
1801	struct snd_timer_info *info;
1802	struct snd_timer *t;
1803	int err = 0;
1804
1805	tu = file->private_data;
1806	if (!tu->timeri)
1807		return -EBADFD;
1808	t = tu->timeri->timer;
1809	if (!t)
1810		return -EBADFD;
1811
1812	info = kzalloc(sizeof(*info), GFP_KERNEL);
1813	if (! info)
1814		return -ENOMEM;
1815	info->card = t->card ? t->card->number : -1;
1816	if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1817		info->flags |= SNDRV_TIMER_FLG_SLAVE;
1818	strscpy(info->id, t->id, sizeof(info->id));
1819	strscpy(info->name, t->name, sizeof(info->name));
1820	info->resolution = t->hw.resolution;
1821	if (copy_to_user(_info, info, sizeof(*_info)))
1822		err = -EFAULT;
1823	kfree(info);
1824	return err;
1825}
1826
1827static int snd_timer_user_params(struct file *file,
1828				 struct snd_timer_params __user *_params)
1829{
1830	struct snd_timer_user *tu;
1831	struct snd_timer_params params;
1832	struct snd_timer *t;
1833	int err;
1834
1835	tu = file->private_data;
1836	if (!tu->timeri)
1837		return -EBADFD;
1838	t = tu->timeri->timer;
1839	if (!t)
1840		return -EBADFD;
1841	if (copy_from_user(&params, _params, sizeof(params)))
1842		return -EFAULT;
1843	if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1844		u64 resolution;
1845
1846		if (params.ticks < 1) {
1847			err = -EINVAL;
1848			goto _end;
1849		}
1850
1851		/* Don't allow resolution less than 1ms */
1852		resolution = snd_timer_resolution(tu->timeri);
1853		resolution *= params.ticks;
1854		if (resolution < 1000000) {
1855			err = -EINVAL;
1856			goto _end;
1857		}
1858	}
1859	if (params.queue_size > 0 &&
1860	    (params.queue_size < 32 || params.queue_size > 1024)) {
1861		err = -EINVAL;
1862		goto _end;
1863	}
1864	if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1865			      (1<<SNDRV_TIMER_EVENT_TICK)|
1866			      (1<<SNDRV_TIMER_EVENT_START)|
1867			      (1<<SNDRV_TIMER_EVENT_STOP)|
1868			      (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1869			      (1<<SNDRV_TIMER_EVENT_PAUSE)|
1870			      (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1871			      (1<<SNDRV_TIMER_EVENT_RESUME)|
1872			      (1<<SNDRV_TIMER_EVENT_MSTART)|
1873			      (1<<SNDRV_TIMER_EVENT_MSTOP)|
1874			      (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1875			      (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1876			      (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1877			      (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1878		err = -EINVAL;
1879		goto _end;
1880	}
1881	snd_timer_stop(tu->timeri);
1882	spin_lock_irq(&t->lock);
1883	tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1884			       SNDRV_TIMER_IFLG_EXCLUSIVE|
1885			       SNDRV_TIMER_IFLG_EARLY_EVENT);
1886	if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1887		tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1888	if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1889		tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1890	if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1891		tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1892	spin_unlock_irq(&t->lock);
1893	if (params.queue_size > 0 &&
1894	    (unsigned int)tu->queue_size != params.queue_size) {
1895		err = realloc_user_queue(tu, params.queue_size);
1896		if (err < 0)
1897			goto _end;
1898	}
1899	spin_lock_irq(&tu->qlock);
1900	tu->qhead = tu->qtail = tu->qused = 0;
1901	if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1902		if (tu->tread) {
1903			struct snd_timer_tread64 tread;
1904			memset(&tread, 0, sizeof(tread));
1905			tread.event = SNDRV_TIMER_EVENT_EARLY;
1906			tread.tstamp_sec = 0;
1907			tread.tstamp_nsec = 0;
1908			tread.val = 0;
1909			snd_timer_user_append_to_tqueue(tu, &tread);
1910		} else {
1911			struct snd_timer_read *r = &tu->queue[0];
1912			r->resolution = 0;
1913			r->ticks = 0;
1914			tu->qused++;
1915			tu->qtail++;
1916		}
1917	}
1918	tu->filter = params.filter;
1919	tu->ticks = params.ticks;
1920	spin_unlock_irq(&tu->qlock);
1921	err = 0;
1922 _end:
1923	if (copy_to_user(_params, &params, sizeof(params)))
1924		return -EFAULT;
1925	return err;
1926}
1927
1928static int snd_timer_user_status32(struct file *file,
1929				   struct snd_timer_status32 __user *_status)
1930 {
1931	struct snd_timer_user *tu;
1932	struct snd_timer_status32 status;
1933
1934	tu = file->private_data;
1935	if (!tu->timeri)
1936		return -EBADFD;
1937	memset(&status, 0, sizeof(status));
1938	status.tstamp_sec = tu->tstamp.tv_sec;
1939	status.tstamp_nsec = tu->tstamp.tv_nsec;
1940	status.resolution = snd_timer_resolution(tu->timeri);
1941	status.lost = tu->timeri->lost;
1942	status.overrun = tu->overrun;
1943	spin_lock_irq(&tu->qlock);
1944	status.queue = tu->qused;
1945	spin_unlock_irq(&tu->qlock);
1946	if (copy_to_user(_status, &status, sizeof(status)))
1947		return -EFAULT;
1948	return 0;
1949}
1950
1951static int snd_timer_user_status64(struct file *file,
1952				   struct snd_timer_status64 __user *_status)
1953{
1954	struct snd_timer_user *tu;
1955	struct snd_timer_status64 status;
1956
1957	tu = file->private_data;
1958	if (!tu->timeri)
1959		return -EBADFD;
1960	memset(&status, 0, sizeof(status));
1961	status.tstamp_sec = tu->tstamp.tv_sec;
1962	status.tstamp_nsec = tu->tstamp.tv_nsec;
1963	status.resolution = snd_timer_resolution(tu->timeri);
1964	status.lost = tu->timeri->lost;
1965	status.overrun = tu->overrun;
1966	spin_lock_irq(&tu->qlock);
1967	status.queue = tu->qused;
1968	spin_unlock_irq(&tu->qlock);
1969	if (copy_to_user(_status, &status, sizeof(status)))
1970		return -EFAULT;
1971	return 0;
1972}
1973
1974static int snd_timer_user_start(struct file *file)
1975{
1976	int err;
1977	struct snd_timer_user *tu;
1978
1979	tu = file->private_data;
1980	if (!tu->timeri)
1981		return -EBADFD;
1982	snd_timer_stop(tu->timeri);
1983	tu->timeri->lost = 0;
1984	tu->last_resolution = 0;
1985	err = snd_timer_start(tu->timeri, tu->ticks);
1986	if (err < 0)
1987		return err;
1988	return 0;
1989}
1990
1991static int snd_timer_user_stop(struct file *file)
1992{
1993	int err;
1994	struct snd_timer_user *tu;
1995
1996	tu = file->private_data;
1997	if (!tu->timeri)
1998		return -EBADFD;
1999	err = snd_timer_stop(tu->timeri);
2000	if (err < 0)
2001		return err;
2002	return 0;
2003}
2004
2005static int snd_timer_user_continue(struct file *file)
2006{
2007	int err;
2008	struct snd_timer_user *tu;
2009
2010	tu = file->private_data;
2011	if (!tu->timeri)
2012		return -EBADFD;
2013	/* start timer instead of continue if it's not used before */
2014	if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
2015		return snd_timer_user_start(file);
2016	tu->timeri->lost = 0;
2017	err = snd_timer_continue(tu->timeri);
2018	if (err < 0)
2019		return err;
2020	return 0;
2021}
2022
2023static int snd_timer_user_pause(struct file *file)
2024{
2025	int err;
2026	struct snd_timer_user *tu;
2027
2028	tu = file->private_data;
2029	if (!tu->timeri)
2030		return -EBADFD;
2031	err = snd_timer_pause(tu->timeri);
2032	if (err < 0)
2033		return err;
2034	return 0;
2035}
2036
2037static int snd_timer_user_tread(void __user *argp, struct snd_timer_user *tu,
2038				unsigned int cmd, bool compat)
2039{
2040	int __user *p = argp;
2041	int xarg, old_tread;
2042
2043	if (tu->timeri)	/* too late */
2044		return -EBUSY;
2045	if (get_user(xarg, p))
2046		return -EFAULT;
2047
2048	old_tread = tu->tread;
2049
2050	if (!xarg)
2051		tu->tread = TREAD_FORMAT_NONE;
2052	else if (cmd == SNDRV_TIMER_IOCTL_TREAD64 ||
2053		 (IS_ENABLED(CONFIG_64BIT) && !compat))
2054		tu->tread = TREAD_FORMAT_TIME64;
2055	else
2056		tu->tread = TREAD_FORMAT_TIME32;
2057
2058	if (tu->tread != old_tread &&
2059	    realloc_user_queue(tu, tu->queue_size) < 0) {
2060		tu->tread = old_tread;
2061		return -ENOMEM;
2062	}
2063
2064	return 0;
2065}
2066
2067enum {
2068	SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
2069	SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
2070	SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
2071	SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
2072};
2073
2074static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2075				 unsigned long arg, bool compat)
2076{
2077	struct snd_timer_user *tu;
2078	void __user *argp = (void __user *)arg;
2079	int __user *p = argp;
2080
2081	tu = file->private_data;
2082	switch (cmd) {
2083	case SNDRV_TIMER_IOCTL_PVERSION:
2084		return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
2085	case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
2086		return snd_timer_user_next_device(argp);
2087	case SNDRV_TIMER_IOCTL_TREAD_OLD:
2088	case SNDRV_TIMER_IOCTL_TREAD64:
2089		return snd_timer_user_tread(argp, tu, cmd, compat);
2090	case SNDRV_TIMER_IOCTL_GINFO:
2091		return snd_timer_user_ginfo(file, argp);
2092	case SNDRV_TIMER_IOCTL_GPARAMS:
2093		return snd_timer_user_gparams(file, argp);
2094	case SNDRV_TIMER_IOCTL_GSTATUS:
2095		return snd_timer_user_gstatus(file, argp);
2096	case SNDRV_TIMER_IOCTL_SELECT:
2097		return snd_timer_user_tselect(file, argp);
2098	case SNDRV_TIMER_IOCTL_INFO:
2099		return snd_timer_user_info(file, argp);
2100	case SNDRV_TIMER_IOCTL_PARAMS:
2101		return snd_timer_user_params(file, argp);
2102	case SNDRV_TIMER_IOCTL_STATUS32:
2103		return snd_timer_user_status32(file, argp);
2104	case SNDRV_TIMER_IOCTL_STATUS64:
2105		return snd_timer_user_status64(file, argp);
2106	case SNDRV_TIMER_IOCTL_START:
2107	case SNDRV_TIMER_IOCTL_START_OLD:
2108		return snd_timer_user_start(file);
2109	case SNDRV_TIMER_IOCTL_STOP:
2110	case SNDRV_TIMER_IOCTL_STOP_OLD:
2111		return snd_timer_user_stop(file);
2112	case SNDRV_TIMER_IOCTL_CONTINUE:
2113	case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
2114		return snd_timer_user_continue(file);
2115	case SNDRV_TIMER_IOCTL_PAUSE:
2116	case SNDRV_TIMER_IOCTL_PAUSE_OLD:
2117		return snd_timer_user_pause(file);
2118	}
2119	return -ENOTTY;
2120}
2121
2122static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2123				 unsigned long arg)
2124{
2125	struct snd_timer_user *tu = file->private_data;
2126	long ret;
2127
2128	mutex_lock(&tu->ioctl_lock);
2129	ret = __snd_timer_user_ioctl(file, cmd, arg, false);
2130	mutex_unlock(&tu->ioctl_lock);
2131	return ret;
2132}
2133
2134static int snd_timer_user_fasync(int fd, struct file * file, int on)
2135{
2136	struct snd_timer_user *tu;
2137
2138	tu = file->private_data;
2139	return snd_fasync_helper(fd, file, on, &tu->fasync);
2140}
2141
2142static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2143				   size_t count, loff_t *offset)
2144{
2145	struct snd_timer_tread64 *tread;
2146	struct snd_timer_tread32 tread32;
2147	struct snd_timer_user *tu;
2148	long result = 0, unit;
2149	int qhead;
2150	int err = 0;
2151
2152	tu = file->private_data;
2153	switch (tu->tread) {
2154	case TREAD_FORMAT_TIME64:
2155		unit = sizeof(struct snd_timer_tread64);
2156		break;
2157	case TREAD_FORMAT_TIME32:
2158		unit = sizeof(struct snd_timer_tread32);
2159		break;
2160	case TREAD_FORMAT_NONE:
2161		unit = sizeof(struct snd_timer_read);
2162		break;
2163	default:
2164		WARN_ONCE(1, "Corrupt snd_timer_user\n");
2165		return -ENOTSUPP;
2166	}
2167
2168	mutex_lock(&tu->ioctl_lock);
2169	spin_lock_irq(&tu->qlock);
2170	while ((long)count - result >= unit) {
2171		while (!tu->qused) {
2172			wait_queue_entry_t wait;
2173
2174			if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2175				err = -EAGAIN;
2176				goto _error;
2177			}
2178
2179			set_current_state(TASK_INTERRUPTIBLE);
2180			init_waitqueue_entry(&wait, current);
2181			add_wait_queue(&tu->qchange_sleep, &wait);
2182
2183			spin_unlock_irq(&tu->qlock);
2184			mutex_unlock(&tu->ioctl_lock);
2185			schedule();
2186			mutex_lock(&tu->ioctl_lock);
2187			spin_lock_irq(&tu->qlock);
2188
2189			remove_wait_queue(&tu->qchange_sleep, &wait);
2190
2191			if (tu->disconnected) {
2192				err = -ENODEV;
2193				goto _error;
2194			}
2195			if (signal_pending(current)) {
2196				err = -ERESTARTSYS;
2197				goto _error;
2198			}
2199		}
2200
2201		qhead = tu->qhead++;
2202		tu->qhead %= tu->queue_size;
2203		tu->qused--;
2204		spin_unlock_irq(&tu->qlock);
2205
2206		tread = &tu->tqueue[qhead];
2207
2208		switch (tu->tread) {
2209		case TREAD_FORMAT_TIME64:
2210			if (copy_to_user(buffer, tread,
2211					 sizeof(struct snd_timer_tread64)))
2212				err = -EFAULT;
2213			break;
2214		case TREAD_FORMAT_TIME32:
2215			memset(&tread32, 0, sizeof(tread32));
2216			tread32 = (struct snd_timer_tread32) {
2217				.event = tread->event,
2218				.tstamp_sec = tread->tstamp_sec,
2219				.tstamp_nsec = tread->tstamp_nsec,
2220				.val = tread->val,
2221			};
2222
2223			if (copy_to_user(buffer, &tread32, sizeof(tread32)))
2224				err = -EFAULT;
2225			break;
2226		case TREAD_FORMAT_NONE:
2227			if (copy_to_user(buffer, &tu->queue[qhead],
2228					 sizeof(struct snd_timer_read)))
2229				err = -EFAULT;
2230			break;
2231		default:
2232			err = -ENOTSUPP;
2233			break;
2234		}
2235
2236		spin_lock_irq(&tu->qlock);
2237		if (err < 0)
2238			goto _error;
2239		result += unit;
2240		buffer += unit;
2241	}
2242 _error:
2243	spin_unlock_irq(&tu->qlock);
2244	mutex_unlock(&tu->ioctl_lock);
2245	return result > 0 ? result : err;
2246}
2247
2248static __poll_t snd_timer_user_poll(struct file *file, poll_table * wait)
2249{
2250        __poll_t mask;
2251        struct snd_timer_user *tu;
2252
2253        tu = file->private_data;
2254
2255        poll_wait(file, &tu->qchange_sleep, wait);
2256
2257	mask = 0;
2258	spin_lock_irq(&tu->qlock);
2259	if (tu->qused)
2260		mask |= EPOLLIN | EPOLLRDNORM;
2261	if (tu->disconnected)
2262		mask |= EPOLLERR;
2263	spin_unlock_irq(&tu->qlock);
2264
2265	return mask;
2266}
2267
2268#ifdef CONFIG_COMPAT
2269#include "timer_compat.c"
2270#else
2271#define snd_timer_user_ioctl_compat	NULL
2272#endif
2273
2274static const struct file_operations snd_timer_f_ops =
2275{
2276	.owner =	THIS_MODULE,
2277	.read =		snd_timer_user_read,
2278	.open =		snd_timer_user_open,
2279	.release =	snd_timer_user_release,
2280	.llseek =	no_llseek,
2281	.poll =		snd_timer_user_poll,
2282	.unlocked_ioctl =	snd_timer_user_ioctl,
2283	.compat_ioctl =	snd_timer_user_ioctl_compat,
2284	.fasync = 	snd_timer_user_fasync,
2285};
2286
2287/* unregister the system timer */
2288static void snd_timer_free_all(void)
2289{
2290	struct snd_timer *timer, *n;
2291
2292	list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2293		snd_timer_free(timer);
2294}
2295
2296static struct device timer_dev;
2297
2298/*
2299 *  ENTRY functions
2300 */
2301
2302static int __init alsa_timer_init(void)
2303{
2304	int err;
2305
2306	snd_device_initialize(&timer_dev, NULL);
2307	dev_set_name(&timer_dev, "timer");
2308
2309#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2310	snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2311			      "system timer");
2312#endif
2313
2314	err = snd_timer_register_system();
2315	if (err < 0) {
2316		pr_err("ALSA: unable to register system timer (%i)\n", err);
2317		goto put_timer;
2318	}
2319
2320	err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2321				  &snd_timer_f_ops, NULL, &timer_dev);
2322	if (err < 0) {
2323		pr_err("ALSA: unable to register timer device (%i)\n", err);
2324		snd_timer_free_all();
2325		goto put_timer;
2326	}
2327
2328	snd_timer_proc_init();
2329	return 0;
2330
2331put_timer:
2332	put_device(&timer_dev);
2333	return err;
2334}
2335
2336static void __exit alsa_timer_exit(void)
2337{
2338	snd_unregister_device(&timer_dev);
2339	snd_timer_free_all();
2340	put_device(&timer_dev);
2341	snd_timer_proc_done();
2342#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2343	snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2344#endif
2345}
2346
2347module_init(alsa_timer_init)
2348module_exit(alsa_timer_exit)