[linux-block.git] / sound / core / seq / seq_timer.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *   ALSA sequencer Timer
 *   Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
 *                              Jaroslav Kysela <perex@perex.cz>
 */

#include <sound/core.h>
#include <linux/slab.h>
#include "seq_timer.h"
#include "seq_queue.h"
#include "seq_info.h"

/* allowed sequencer timer frequencies, in Hz */
#define MIN_FREQUENCY		10
#define MAX_FREQUENCY		6250
#define DEFAULT_FREQUENCY	1000

#define SKEW_BASE	0x10000	/* 16bit shift */

static void snd_seq_timer_set_tick_resolution(struct snd_seq_timer *tmr)
{
	if (tmr->tempo < 1000000)
		tmr->tick.resolution = (tmr->tempo * 1000) / tmr->ppq;
	else {
		/* might overflow.. */
		unsigned int s;
		s = tmr->tempo % tmr->ppq;
		s = (s * 1000) / tmr->ppq;
		tmr->tick.resolution = (tmr->tempo / tmr->ppq) * 1000;
		tmr->tick.resolution += s;
	}
	if (tmr->tick.resolution <= 0)
		tmr->tick.resolution = 1;
	snd_seq_timer_update_tick(&tmr->tick, 0);
}

/* create new timer (constructor) */
struct snd_seq_timer *snd_seq_timer_new(void)
{
	struct snd_seq_timer *tmr;
	
	tmr = kzalloc(sizeof(*tmr), GFP_KERNEL);
	if (!tmr)
		return NULL;
	spin_lock_init(&tmr->lock);

	/* reset setup to defaults */
	snd_seq_timer_defaults(tmr);
	
	/* reset time */
	snd_seq_timer_reset(tmr);
	
	return tmr;
}

/* delete timer (destructor) */
void snd_seq_timer_delete(struct snd_seq_timer **tmr)
{
	struct snd_seq_timer *t = *tmr;
	*tmr = NULL;

	if (t == NULL) {
		pr_debug("ALSA: seq: snd_seq_timer_delete() called with NULL timer\n");
		return;
	}
	t->running = 0;

	/* reset time */
	snd_seq_timer_stop(t);
	snd_seq_timer_reset(t);

	kfree(t);
}

void snd_seq_timer_defaults(struct snd_seq_timer * tmr)
{
	unsigned long flags;

	spin_lock_irqsave(&tmr->lock, flags);
	/* setup defaults */
	tmr->ppq = 96;		/* 96 PPQ */
	tmr->tempo = 500000;	/* 120 BPM */
	snd_seq_timer_set_tick_resolution(tmr);
	tmr->running = 0;

	tmr->type = SNDRV_SEQ_TIMER_ALSA;
	tmr->alsa_id.dev_class = seq_default_timer_class;
	tmr->alsa_id.dev_sclass = seq_default_timer_sclass;
	tmr->alsa_id.card = seq_default_timer_card;
	tmr->alsa_id.device = seq_default_timer_device;
	tmr->alsa_id.subdevice = seq_default_timer_subdevice;
	tmr->preferred_resolution = seq_default_timer_resolution;

	tmr->skew = tmr->skew_base = SKEW_BASE;
	spin_unlock_irqrestore(&tmr->lock, flags);
}

static void seq_timer_reset(struct snd_seq_timer *tmr)
{
	/* reset time & songposition */
	tmr->cur_time.tv_sec = 0;
	tmr->cur_time.tv_nsec = 0;

	tmr->tick.cur_tick = 0;
	tmr->tick.fraction = 0;
}

void snd_seq_timer_reset(struct snd_seq_timer *tmr)
{
	unsigned long flags;

	spin_lock_irqsave(&tmr->lock, flags);
	seq_timer_reset(tmr);
	spin_unlock_irqrestore(&tmr->lock, flags);
}


/* called by timer interrupt routine. the period time since previous invocation is passed */
static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri,
				    unsigned long resolution,
				    unsigned long ticks)
{
	unsigned long flags;
	struct snd_seq_queue *q = timeri->callback_data;
	struct snd_seq_timer *tmr;

	if (q == NULL)
		return;
	tmr = q->timer;
	if (tmr == NULL)
		return;
	spin_lock_irqsave(&tmr->lock, flags);
	if (!tmr->running) {
		spin_unlock_irqrestore(&tmr->lock, flags);
		return;
	}

	resolution *= ticks;
	if (tmr->skew != tmr->skew_base) {
		/* FIXME: assuming skew_base = 0x10000 */
		resolution = (resolution >> 16) * tmr->skew +
			(((resolution & 0xffff) * tmr->skew) >> 16);
	}

	/* update timer */
	snd_seq_inc_time_nsec(&tmr->cur_time, resolution);

	/* calculate current tick */
	snd_seq_timer_update_tick(&tmr->tick, resolution);

	/* register actual time of this timer update */
	ktime_get_ts64(&tmr->last_update);

	spin_unlock_irqrestore(&tmr->lock, flags);

	/* check queues and dispatch events */
	snd_seq_check_queue(q, 1, 0);
}

/* set current tempo */
int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo)
{
	unsigned long flags;

	if (snd_BUG_ON(!tmr))
		return -EINVAL;
	if (tempo <= 0)
		return -EINVAL;
	spin_lock_irqsave(&tmr->lock, flags);
	if ((unsigned int)tempo != tmr->tempo) {
		tmr->tempo = tempo;
		snd_seq_timer_set_tick_resolution(tmr);
	}
	spin_unlock_irqrestore(&tmr->lock, flags);
	return 0;
}

/* set current tempo and ppq in a shot */
int snd_seq_timer_set_tempo_ppq(struct snd_seq_timer *tmr, int tempo, int ppq)
{
	int changed;
	unsigned long flags;

	if (snd_BUG_ON(!tmr))
		return -EINVAL;
	if (tempo <= 0 || ppq <= 0)
		return -EINVAL;
	spin_lock_irqsave(&tmr->lock, flags);
	if (tmr->running && (ppq != tmr->ppq)) {
		/* refuse to change ppq on running timers */
		/* because it will upset the song position (ticks) */
		spin_unlock_irqrestore(&tmr->lock, flags);
		pr_debug("ALSA: seq: cannot change ppq of a running timer\n");
		return -EBUSY;
	}
	changed = (tempo != tmr->tempo) || (ppq != tmr->ppq);
	tmr->tempo = tempo;
	tmr->ppq = ppq;
	if (changed)
		snd_seq_timer_set_tick_resolution(tmr);
	spin_unlock_irqrestore(&tmr->lock, flags);
	return 0;
}

/* set current tick position */
int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr,
				    snd_seq_tick_time_t position)
{
	unsigned long flags;

	if (snd_BUG_ON(!tmr))
		return -EINVAL;

	spin_lock_irqsave(&tmr->lock, flags);
	tmr->tick.cur_tick = position;
	tmr->tick.fraction = 0;
	spin_unlock_irqrestore(&tmr->lock, flags);
	return 0;
}

/* set current real-time position */
int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr,
				    snd_seq_real_time_t position)
{
	unsigned long flags;

	if (snd_BUG_ON(!tmr))
		return -EINVAL;

	snd_seq_sanity_real_time(&position);
	spin_lock_irqsave(&tmr->lock, flags);
	tmr->cur_time = position;
	spin_unlock_irqrestore(&tmr->lock, flags);
	return 0;
}

/* set timer skew */
int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew,
			   unsigned int base)
{
	unsigned long flags;

	if (snd_BUG_ON(!tmr))
		return -EINVAL;

	/* FIXME */
	if (base != SKEW_BASE) {
		pr_debug("ALSA: seq: invalid skew base 0x%x\n", base);
		return -EINVAL;
	}
	spin_lock_irqsave(&tmr->lock, flags);
	tmr->skew = skew;
	spin_unlock_irqrestore(&tmr->lock, flags);
	return 0;
}

int snd_seq_timer_open(struct snd_seq_queue *q)
{
	struct snd_timer_instance *t;
	struct snd_seq_timer *tmr;
	char str[32];
	int err;

	tmr = q->timer;
	if (snd_BUG_ON(!tmr))
		return -EINVAL;
	if (tmr->timeri)
		return -EBUSY;
	sprintf(str, "sequencer queue %i", q->queue);
	if (tmr->type != SNDRV_SEQ_TIMER_ALSA)	/* standard ALSA timer */
		return -EINVAL;
	if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
		tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
	t = snd_timer_instance_new(str);
	if (!t)
		return -ENOMEM;
	t->callback = snd_seq_timer_interrupt;
	t->callback_data = q;
	t->flags |= SNDRV_TIMER_IFLG_AUTO;
	err = snd_timer_open(t, &tmr->alsa_id, q->queue);
	if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) {
		if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL ||
		    tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) {
			struct snd_timer_id tid;
			memset(&tid, 0, sizeof(tid));
			tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
			tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
			tid.card = -1;
			tid.device = SNDRV_TIMER_GLOBAL_SYSTEM;
			err = snd_timer_open(t, &tid, q->queue);
		}
	}
	if (err < 0) {
		pr_err("ALSA: seq fatal error: cannot create timer (%i)\n", err);
		snd_timer_instance_free(t);
		return err;
	}
	spin_lock_irq(&tmr->lock);
	tmr->timeri = t;
	spin_unlock_irq(&tmr->lock);
	return 0;
}

int snd_seq_timer_close(struct snd_seq_queue *q)
{
	struct snd_seq_timer *tmr;
	struct snd_timer_instance *t;
	
	tmr = q->timer;
	if (snd_BUG_ON(!tmr))
		return -EINVAL;
	spin_lock_irq(&tmr->lock);
	t = tmr->timeri;
	tmr->timeri = NULL;
	spin_unlock_irq(&tmr->lock);
	if (t) {
		snd_timer_close(t);
		snd_timer_instance_free(t);
	}
	return 0;
}

static int seq_timer_stop(struct snd_seq_timer *tmr)
{
	if (! tmr->timeri)
		return -EINVAL;
	if (!tmr->running)
		return 0;
	tmr->running = 0;
	snd_timer_pause(tmr->timeri);
	return 0;
}

int snd_seq_timer_stop(struct snd_seq_timer *tmr)
{
	unsigned long flags;
	int err;

	spin_lock_irqsave(&tmr->lock, flags);
	err = seq_timer_stop(tmr);
	spin_unlock_irqrestore(&tmr->lock, flags);
	return err;
}

static int initialize_timer(struct snd_seq_timer *tmr)
{
	struct snd_timer *t;
	unsigned long freq;

	t = tmr->timeri->timer;
	if (!t)
		return -EINVAL;

	freq = tmr->preferred_resolution;
	if (!freq)
		freq = DEFAULT_FREQUENCY;
	else if (freq < MIN_FREQUENCY)
		freq = MIN_FREQUENCY;
	else if (freq > MAX_FREQUENCY)
		freq = MAX_FREQUENCY;

	tmr->ticks = 1;
	if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
		unsigned long r = snd_timer_resolution(tmr->timeri);
		if (r) {
			tmr->ticks = (unsigned int)(1000000000uL / (r * freq));
			if (! tmr->ticks)
				tmr->ticks = 1;
		}
	}
	tmr->initialized = 1;
	return 0;
}

static int seq_timer_start(struct snd_seq_timer *tmr)
{
	if (! tmr->timeri)
		return -EINVAL;
	if (tmr->running)
		seq_timer_stop(tmr);
	seq_timer_reset(tmr);
	if (initialize_timer(tmr) < 0)
		return -EINVAL;
	snd_timer_start(tmr->timeri, tmr->ticks);
	tmr->running = 1;
	ktime_get_ts64(&tmr->last_update);
	return 0;
}

int snd_seq_timer_start(struct snd_seq_timer *tmr)
{
	unsigned long flags;
	int err;

	spin_lock_irqsave(&tmr->lock, flags);
	err = seq_timer_start(tmr);
	spin_unlock_irqrestore(&tmr->lock, flags);
	return err;
}

static int seq_timer_continue(struct snd_seq_timer *tmr)
{
	if (! tmr->timeri)
		return -EINVAL;
	if (tmr->running)
		return -EBUSY;
	if (! tmr->initialized) {
		seq_timer_reset(tmr);
		if (initialize_timer(tmr) < 0)
			return -EINVAL;
	}
	snd_timer_start(tmr->timeri, tmr->ticks);
	tmr->running = 1;
	ktime_get_ts64(&tmr->last_update);
	return 0;
}

int snd_seq_timer_continue(struct snd_seq_timer *tmr)
{
	unsigned long flags;
	int err;

	spin_lock_irqsave(&tmr->lock, flags);
	err = seq_timer_continue(tmr);
	spin_unlock_irqrestore(&tmr->lock, flags);
	return err;
}

/* return current 'real' time. use timeofday() to get better granularity. */
snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr,
					       bool adjust_ktime)
{
	snd_seq_real_time_t cur_time;
	unsigned long flags;

	spin_lock_irqsave(&tmr->lock, flags);
	cur_time = tmr->cur_time;
	if (adjust_ktime && tmr->running) {
		struct timespec64 tm;

		ktime_get_ts64(&tm);
		tm = timespec64_sub(tm, tmr->last_update);
		cur_time.tv_nsec += tm.tv_nsec;
		cur_time.tv_sec += tm.tv_sec;
		snd_seq_sanity_real_time(&cur_time);
	}
	spin_unlock_irqrestore(&tmr->lock, flags);
	return cur_time;	
}

/* TODO: use interpolation on tick queue (will only be useful for very
 high PPQ values) */
snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr)
{
	snd_seq_tick_time_t cur_tick;
	unsigned long flags;

	spin_lock_irqsave(&tmr->lock, flags);
	cur_tick = tmr->tick.cur_tick;
	spin_unlock_irqrestore(&tmr->lock, flags);
	return cur_tick;
}


#ifdef CONFIG_SND_PROC_FS
/* exported to seq_info.c */
void snd_seq_info_timer_read(struct snd_info_entry *entry,
			     struct snd_info_buffer *buffer)
{
	int idx;
	struct snd_seq_queue *q;
	struct snd_seq_timer *tmr;
	struct snd_timer_instance *ti;
	unsigned long resolution;
	
	for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) {
		q = queueptr(idx);
		if (q == NULL)
			continue;
		mutex_lock(&q->timer_mutex);
		tmr = q->timer;
		if (!tmr)
			goto unlock;
		ti = tmr->timeri;
		if (!ti)
			goto unlock;
		snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name);
		resolution = snd_timer_resolution(ti) * tmr->ticks;
		snd_iprintf(buffer, "  Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000);
		snd_iprintf(buffer, "  Skew : %u / %u\n", tmr->skew, tmr->skew_base);
unlock:
		mutex_unlock(&q->timer_mutex);
		queuefree(q);
 	}
}
#endif /* CONFIG_SND_PROC_FS */
Commit	Line	Data
1a59d1b8	1	// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4 LT	2	/*
	3	* ALSA sequencer Timer
	4	* Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
c1017a4c	5	* Jaroslav Kysela <perex@perex.cz>
1da177e4 LT	6	*/
1da177e4 LT	7
1da177e4 LT	8	#include <sound/core.h>
	9	#include <linux/slab.h>
	10	#include "seq_timer.h"
	11	#include "seq_queue.h"
	12	#include "seq_info.h"
	13
87ef7779 CL	14	/* allowed sequencer timer frequencies, in Hz */
	15	#define MIN_FREQUENCY 10
	16	#define MAX_FREQUENCY 6250
	17	#define DEFAULT_FREQUENCY 1000
	18
1da177e4 LT	19	#define SKEW_BASE 0x10000 /* 16bit shift */
1da177e4 LT	20
a32f6674	21	static void snd_seq_timer_set_tick_resolution(struct snd_seq_timer *tmr)
1da177e4	22	{
a32f6674 CL	23	if (tmr->tempo < 1000000)
a32f6674 CL	24	tmr->tick.resolution = (tmr->tempo * 1000) / tmr->ppq;
1da177e4 LT	25	else {
	26	/* might overflow.. */
	27	unsigned int s;
a32f6674 CL	28	s = tmr->tempo % tmr->ppq;
	29	s = (s * 1000) / tmr->ppq;
	30	tmr->tick.resolution = (tmr->tempo / tmr->ppq) * 1000;
	31	tmr->tick.resolution += s;
1da177e4	32	}
a32f6674 CL	33	if (tmr->tick.resolution <= 0)
	34	tmr->tick.resolution = 1;
	35	snd_seq_timer_update_tick(&tmr->tick, 0);
1da177e4 LT	36	}
	37
	38	/* create new timer (constructor) */
c7e0b5bf	39	struct snd_seq_timer *snd_seq_timer_new(void)
1da177e4	40	{
c7e0b5bf	41	struct snd_seq_timer *tmr;
1da177e4	42
ecca82b4	43	tmr = kzalloc(sizeof(*tmr), GFP_KERNEL);
24db8bba	44	if (!tmr)
1da177e4	45	return NULL;
1da177e4 LT	46	spin_lock_init(&tmr->lock);
	47
	48	/* reset setup to defaults */
	49	snd_seq_timer_defaults(tmr);
	50
	51	/* reset time */
	52	snd_seq_timer_reset(tmr);
	53
	54	return tmr;
	55	}
	56
	57	/* delete timer (destructor) */
c7e0b5bf	58	void snd_seq_timer_delete(struct snd_seq_timer **tmr)
1da177e4	59	{
c7e0b5bf	60	struct snd_seq_timer t = tmr;
1da177e4 LT	61	*tmr = NULL;
	62
	63	if (t == NULL) {
04cc79a0	64	pr_debug("ALSA: seq: snd_seq_timer_delete() called with NULL timer\n");
1da177e4 LT	65	return;
	66	}
	67	t->running = 0;
	68
	69	/* reset time */
	70	snd_seq_timer_stop(t);
	71	snd_seq_timer_reset(t);
	72
	73	kfree(t);
	74	}
	75
c7e0b5bf	76	void snd_seq_timer_defaults(struct snd_seq_timer * tmr)
1da177e4	77	{
2cdc7b63 TI	78	unsigned long flags;
	79
	80	spin_lock_irqsave(&tmr->lock, flags);
1da177e4 LT	81	/* setup defaults */
	82	tmr->ppq = 96; /* 96 PPQ */
	83	tmr->tempo = 500000; /* 120 BPM */
a32f6674	84	snd_seq_timer_set_tick_resolution(tmr);
1da177e4 LT	85	tmr->running = 0;
	86
	87	tmr->type = SNDRV_SEQ_TIMER_ALSA;
	88	tmr->alsa_id.dev_class = seq_default_timer_class;
	89	tmr->alsa_id.dev_sclass = seq_default_timer_sclass;
	90	tmr->alsa_id.card = seq_default_timer_card;
	91	tmr->alsa_id.device = seq_default_timer_device;
	92	tmr->alsa_id.subdevice = seq_default_timer_subdevice;
	93	tmr->preferred_resolution = seq_default_timer_resolution;
	94
	95	tmr->skew = tmr->skew_base = SKEW_BASE;
2cdc7b63	96	spin_unlock_irqrestore(&tmr->lock, flags);
1da177e4 LT	97	}
1da177e4 LT	98
2cdc7b63	99	static void seq_timer_reset(struct snd_seq_timer *tmr)
1da177e4	100	{
1da177e4 LT	101	/* reset time & songposition */
	102	tmr->cur_time.tv_sec = 0;
	103	tmr->cur_time.tv_nsec = 0;
	104
	105	tmr->tick.cur_tick = 0;
	106	tmr->tick.fraction = 0;
2cdc7b63 TI	107	}
	108
	109	void snd_seq_timer_reset(struct snd_seq_timer *tmr)
	110	{
	111	unsigned long flags;
1da177e4	112
2cdc7b63 TI	113	spin_lock_irqsave(&tmr->lock, flags);
2cdc7b63 TI	114	seq_timer_reset(tmr);
1da177e4 LT	115	spin_unlock_irqrestore(&tmr->lock, flags);
	116	}
	117
	118
	119	/* called by timer interrupt routine. the period time since previous invocation is passed */
c7e0b5bf	120	static void snd_seq_timer_interrupt(struct snd_timer_instance *timeri,
1da177e4 LT	121	unsigned long resolution,
	122	unsigned long ticks)
	123	{
	124	unsigned long flags;
c7e0b5bf TI	125	struct snd_seq_queue *q = timeri->callback_data;
c7e0b5bf TI	126	struct snd_seq_timer *tmr;
1da177e4 LT	127
	128	if (q == NULL)
	129	return;
	130	tmr = q->timer;
	131	if (tmr == NULL)
	132	return;
2cdc7b63 TI	133	spin_lock_irqsave(&tmr->lock, flags);
	134	if (!tmr->running) {
	135	spin_unlock_irqrestore(&tmr->lock, flags);
1da177e4	136	return;
2cdc7b63	137	}
1da177e4 LT	138
	139	resolution *= ticks;
	140	if (tmr->skew != tmr->skew_base) {
	141	/* FIXME: assuming skew_base = 0x10000 */
	142	resolution = (resolution >> 16) * tmr->skew +
	143	(((resolution & 0xffff) * tmr->skew) >> 16);
	144	}
	145
1da177e4 LT	146	/* update timer */
	147	snd_seq_inc_time_nsec(&tmr->cur_time, resolution);
	148
	149	/* calculate current tick */
	150	snd_seq_timer_update_tick(&tmr->tick, resolution);
	151
	152	/* register actual time of this timer update */
3915bf29	153	ktime_get_ts64(&tmr->last_update);
1da177e4 LT	154
	155	spin_unlock_irqrestore(&tmr->lock, flags);
	156
	157	/* check queues and dispatch events */
	158	snd_seq_check_queue(q, 1, 0);
	159	}
	160
	161	/* set current tempo */
c7e0b5bf	162	int snd_seq_timer_set_tempo(struct snd_seq_timer * tmr, int tempo)
1da177e4 LT	163	{
	164	unsigned long flags;
	165
7eaa943c TI	166	if (snd_BUG_ON(!tmr))
7eaa943c TI	167	return -EINVAL;
1da177e4 LT	168	if (tempo <= 0)
	169	return -EINVAL;
	170	spin_lock_irqsave(&tmr->lock, flags);
	171	if ((unsigned int)tempo != tmr->tempo) {
	172	tmr->tempo = tempo;
a32f6674	173	snd_seq_timer_set_tick_resolution(tmr);
1da177e4 LT	174	}
	175	spin_unlock_irqrestore(&tmr->lock, flags);
	176	return 0;
	177	}
	178
671ec859 TI	179	/* set current tempo and ppq in a shot */
671ec859 TI	180	int snd_seq_timer_set_tempo_ppq(struct snd_seq_timer *tmr, int tempo, int ppq)
1da177e4	181	{
671ec859	182	int changed;
1da177e4 LT	183	unsigned long flags;
1da177e4 LT	184
7eaa943c TI	185	if (snd_BUG_ON(!tmr))
7eaa943c TI	186	return -EINVAL;
671ec859	187	if (tempo <= 0 \|\| ppq <= 0)
1da177e4 LT	188	return -EINVAL;
	189	spin_lock_irqsave(&tmr->lock, flags);
	190	if (tmr->running && (ppq != tmr->ppq)) {
	191	/* refuse to change ppq on running timers */
	192	/* because it will upset the song position (ticks) */
	193	spin_unlock_irqrestore(&tmr->lock, flags);
04cc79a0	194	pr_debug("ALSA: seq: cannot change ppq of a running timer\n");
1da177e4 LT	195	return -EBUSY;
1da177e4 LT	196	}
671ec859 TI	197	changed = (tempo != tmr->tempo) \|\| (ppq != tmr->ppq);
671ec859 TI	198	tmr->tempo = tempo;
1da177e4	199	tmr->ppq = ppq;
671ec859 TI	200	if (changed)
671ec859 TI	201	snd_seq_timer_set_tick_resolution(tmr);
1da177e4 LT	202	spin_unlock_irqrestore(&tmr->lock, flags);
	203	return 0;
	204	}
	205
	206	/* set current tick position */
c7e0b5bf TI	207	int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr,
c7e0b5bf TI	208	snd_seq_tick_time_t position)
1da177e4 LT	209	{
	210	unsigned long flags;
	211
7eaa943c TI	212	if (snd_BUG_ON(!tmr))
7eaa943c TI	213	return -EINVAL;
1da177e4 LT	214
	215	spin_lock_irqsave(&tmr->lock, flags);
	216	tmr->tick.cur_tick = position;
	217	tmr->tick.fraction = 0;
	218	spin_unlock_irqrestore(&tmr->lock, flags);
	219	return 0;
	220	}
	221
	222	/* set current real-time position */
c7e0b5bf TI	223	int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr,
c7e0b5bf TI	224	snd_seq_real_time_t position)
1da177e4 LT	225	{
	226	unsigned long flags;
	227
7eaa943c TI	228	if (snd_BUG_ON(!tmr))
7eaa943c TI	229	return -EINVAL;
1da177e4 LT	230
	231	snd_seq_sanity_real_time(&position);
	232	spin_lock_irqsave(&tmr->lock, flags);
	233	tmr->cur_time = position;
	234	spin_unlock_irqrestore(&tmr->lock, flags);
	235	return 0;
	236	}
	237
	238	/* set timer skew */
c7e0b5bf TI	239	int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew,
c7e0b5bf TI	240	unsigned int base)
1da177e4 LT	241	{
	242	unsigned long flags;
	243
7eaa943c TI	244	if (snd_BUG_ON(!tmr))
7eaa943c TI	245	return -EINVAL;
1da177e4 LT	246
	247	/* FIXME */
	248	if (base != SKEW_BASE) {
04cc79a0	249	pr_debug("ALSA: seq: invalid skew base 0x%x\n", base);
1da177e4 LT	250	return -EINVAL;
	251	}
	252	spin_lock_irqsave(&tmr->lock, flags);
	253	tmr->skew = skew;
	254	spin_unlock_irqrestore(&tmr->lock, flags);
	255	return 0;
	256	}
	257
c7e0b5bf	258	int snd_seq_timer_open(struct snd_seq_queue *q)
1da177e4	259	{
c7e0b5bf TI	260	struct snd_timer_instance *t;
c7e0b5bf TI	261	struct snd_seq_timer *tmr;
1da177e4 LT	262	char str[32];
	263	int err;
	264
	265	tmr = q->timer;
7eaa943c TI	266	if (snd_BUG_ON(!tmr))
7eaa943c TI	267	return -EINVAL;
1da177e4 LT	268	if (tmr->timeri)
	269	return -EBUSY;
	270	sprintf(str, "sequencer queue %i", q->queue);
	271	if (tmr->type != SNDRV_SEQ_TIMER_ALSA) /* standard ALSA timer */
	272	return -EINVAL;
	273	if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
	274	tmr->alsa_id.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
6a34367e TI	275	t = snd_timer_instance_new(str);
	276	if (!t)
	277	return -ENOMEM;
	278	t->callback = snd_seq_timer_interrupt;
	279	t->callback_data = q;
	280	t->flags \|= SNDRV_TIMER_IFLG_AUTO;
	281	err = snd_timer_open(t, &tmr->alsa_id, q->queue);
1da177e4 LT	282	if (err < 0 && tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_SLAVE) {
	283	if (tmr->alsa_id.dev_class != SNDRV_TIMER_CLASS_GLOBAL \|\|
	284	tmr->alsa_id.device != SNDRV_TIMER_GLOBAL_SYSTEM) {
c7e0b5bf	285	struct snd_timer_id tid;
1da177e4 LT	286	memset(&tid, 0, sizeof(tid));
	287	tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
	288	tid.dev_sclass = SNDRV_TIMER_SCLASS_SEQUENCER;
	289	tid.card = -1;
	290	tid.device = SNDRV_TIMER_GLOBAL_SYSTEM;
6a34367e	291	err = snd_timer_open(t, &tid, q->queue);
1da177e4	292	}
66efdc71 TI	293	}
66efdc71 TI	294	if (err < 0) {
04cc79a0	295	pr_err("ALSA: seq fatal error: cannot create timer (%i)\n", err);
6a34367e	296	snd_timer_instance_free(t);
66efdc71	297	return err;
1da177e4	298	}
2cdc7b63	299	spin_lock_irq(&tmr->lock);
1da177e4	300	tmr->timeri = t;
2cdc7b63	301	spin_unlock_irq(&tmr->lock);
1da177e4 LT	302	return 0;
	303	}
	304
c7e0b5bf	305	int snd_seq_timer_close(struct snd_seq_queue *q)
1da177e4	306	{
c7e0b5bf	307	struct snd_seq_timer *tmr;
2cdc7b63	308	struct snd_timer_instance *t;
1da177e4 LT	309
1da177e4 LT	310	tmr = q->timer;
7eaa943c TI	311	if (snd_BUG_ON(!tmr))
7eaa943c TI	312	return -EINVAL;
2cdc7b63 TI	313	spin_lock_irq(&tmr->lock);
	314	t = tmr->timeri;
	315	tmr->timeri = NULL;
	316	spin_unlock_irq(&tmr->lock);
6a34367e	317	if (t) {
2cdc7b63	318	snd_timer_close(t);
6a34367e TI	319	snd_timer_instance_free(t);
6a34367e TI	320	}
1da177e4 LT	321	return 0;
	322	}
	323
2cdc7b63	324	static int seq_timer_stop(struct snd_seq_timer *tmr)
1da177e4 LT	325	{
	326	if (! tmr->timeri)
	327	return -EINVAL;
	328	if (!tmr->running)
	329	return 0;
	330	tmr->running = 0;
	331	snd_timer_pause(tmr->timeri);
	332	return 0;
	333	}
	334
2cdc7b63 TI	335	int snd_seq_timer_stop(struct snd_seq_timer *tmr)
	336	{
	337	unsigned long flags;
	338	int err;
	339
	340	spin_lock_irqsave(&tmr->lock, flags);
	341	err = seq_timer_stop(tmr);
	342	spin_unlock_irqrestore(&tmr->lock, flags);
	343	return err;
	344	}
	345
c7e0b5bf	346	static int initialize_timer(struct snd_seq_timer *tmr)
1da177e4	347	{
c7e0b5bf	348	struct snd_timer *t;
87ef7779 CL	349	unsigned long freq;
87ef7779 CL	350
1da177e4	351	t = tmr->timeri->timer;
43a35428	352	if (!t)
7eaa943c	353	return -EINVAL;
1da177e4	354
87ef7779 CL	355	freq = tmr->preferred_resolution;
	356	if (!freq)
	357	freq = DEFAULT_FREQUENCY;
	358	else if (freq < MIN_FREQUENCY)
	359	freq = MIN_FREQUENCY;
	360	else if (freq > MAX_FREQUENCY)
	361	freq = MAX_FREQUENCY;
	362
1da177e4	363	tmr->ticks = 1;
87ef7779	364	if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
21244e3d	365	unsigned long r = snd_timer_resolution(tmr->timeri);
1da177e4	366	if (r) {
87ef7779	367	tmr->ticks = (unsigned int)(1000000000uL / (r * freq));
1da177e4 LT	368	if (! tmr->ticks)
	369	tmr->ticks = 1;
	370	}
	371	}
	372	tmr->initialized = 1;
	373	return 0;
	374	}
	375
2cdc7b63	376	static int seq_timer_start(struct snd_seq_timer *tmr)
1da177e4 LT	377	{
	378	if (! tmr->timeri)
	379	return -EINVAL;
	380	if (tmr->running)
2cdc7b63 TI	381	seq_timer_stop(tmr);
2cdc7b63 TI	382	seq_timer_reset(tmr);
1da177e4 LT	383	if (initialize_timer(tmr) < 0)
	384	return -EINVAL;
	385	snd_timer_start(tmr->timeri, tmr->ticks);
	386	tmr->running = 1;
3915bf29	387	ktime_get_ts64(&tmr->last_update);
1da177e4 LT	388	return 0;
	389	}
	390
2cdc7b63 TI	391	int snd_seq_timer_start(struct snd_seq_timer *tmr)
	392	{
	393	unsigned long flags;
	394	int err;
	395
	396	spin_lock_irqsave(&tmr->lock, flags);
	397	err = seq_timer_start(tmr);
	398	spin_unlock_irqrestore(&tmr->lock, flags);
	399	return err;
	400	}
	401
	402	static int seq_timer_continue(struct snd_seq_timer *tmr)
1da177e4 LT	403	{
	404	if (! tmr->timeri)
	405	return -EINVAL;
	406	if (tmr->running)
	407	return -EBUSY;
	408	if (! tmr->initialized) {
2cdc7b63	409	seq_timer_reset(tmr);
1da177e4 LT	410	if (initialize_timer(tmr) < 0)
	411	return -EINVAL;
	412	}
	413	snd_timer_start(tmr->timeri, tmr->ticks);
	414	tmr->running = 1;
3915bf29	415	ktime_get_ts64(&tmr->last_update);
1da177e4 LT	416	return 0;
	417	}
	418
2cdc7b63 TI	419	int snd_seq_timer_continue(struct snd_seq_timer *tmr)
	420	{
	421	unsigned long flags;
	422	int err;
	423
	424	spin_lock_irqsave(&tmr->lock, flags);
	425	err = seq_timer_continue(tmr);
	426	spin_unlock_irqrestore(&tmr->lock, flags);
	427	return err;
	428	}
	429
1da177e4	430	/* return current 'real' time. use timeofday() to get better granularity. */
dc749779 TI	431	snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr,
dc749779 TI	432	bool adjust_ktime)
1da177e4 LT	433	{
1da177e4 LT	434	snd_seq_real_time_t cur_time;
2cdc7b63	435	unsigned long flags;
1da177e4	436
2cdc7b63	437	spin_lock_irqsave(&tmr->lock, flags);
1da177e4	438	cur_time = tmr->cur_time;
dc749779	439	if (adjust_ktime && tmr->running) {
3915bf29 AB	440	struct timespec64 tm;
	441
	442	ktime_get_ts64(&tm);
	443	tm = timespec64_sub(tm, tmr->last_update);
9b50898a TI	444	cur_time.tv_nsec += tm.tv_nsec;
9b50898a TI	445	cur_time.tv_sec += tm.tv_sec;
1da177e4 LT	446	snd_seq_sanity_real_time(&cur_time);
1da177e4 LT	447	}
2cdc7b63	448	spin_unlock_irqrestore(&tmr->lock, flags);
1da177e4 LT	449	return cur_time;
	450	}
	451
	452	/* TODO: use interpolation on tick queue (will only be useful for very
	453	high PPQ values) */
c7e0b5bf	454	snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr)
1da177e4	455	{
dc749779 TI	456	snd_seq_tick_time_t cur_tick;
	457	unsigned long flags;
	458
	459	spin_lock_irqsave(&tmr->lock, flags);
	460	cur_tick = tmr->tick.cur_tick;
	461	spin_unlock_irqrestore(&tmr->lock, flags);
	462	return cur_tick;
1da177e4 LT	463	}
	464
	465
cd6a6503	466	#ifdef CONFIG_SND_PROC_FS
1da177e4	467	/* exported to seq_info.c */
c7e0b5bf TI	468	void snd_seq_info_timer_read(struct snd_info_entry *entry,
c7e0b5bf TI	469	struct snd_info_buffer *buffer)
1da177e4 LT	470	{
1da177e4 LT	471	int idx;
c7e0b5bf TI	472	struct snd_seq_queue *q;
	473	struct snd_seq_timer *tmr;
	474	struct snd_timer_instance *ti;
1da177e4 LT	475	unsigned long resolution;
	476
	477	for (idx = 0; idx < SNDRV_SEQ_MAX_QUEUES; idx++) {
	478	q = queueptr(idx);
	479	if (q == NULL)
	480	continue;
60adcfde TI	481	mutex_lock(&q->timer_mutex);
	482	tmr = q->timer;
	483	if (!tmr)
	484	goto unlock;
	485	ti = tmr->timeri;
	486	if (!ti)
	487	goto unlock;
1da177e4 LT	488	snd_iprintf(buffer, "Timer for queue %i : %s\n", q->queue, ti->timer->name);
	489	resolution = snd_timer_resolution(ti) * tmr->ticks;
	490	snd_iprintf(buffer, " Period time : %lu.%09lu\n", resolution / 1000000000, resolution % 1000000000);
	491	snd_iprintf(buffer, " Skew : %u / %u\n", tmr->skew, tmr->skew_base);
60adcfde TI	492	unlock:
60adcfde TI	493	mutex_unlock(&q->timer_mutex);
1da177e4 LT	494	queuefree(q);
	495	}
	496	}
cd6a6503	497	#endif /* CONFIG_SND_PROC_FS */
04f141a8	498