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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* ALSA sequencer Timer
* Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>
*/
#ifndef __SND_SEQ_TIMER_H
#define __SND_SEQ_TIMER_H
#include <sound/timer.h>
#include <sound/seq_kernel.h>
struct snd_seq_timer_tick {
snd_seq_tick_time_t cur_tick; /* current tick */
unsigned long resolution; /* time per tick in nsec */
unsigned long fraction; /* current time per tick in nsec */
};
struct snd_seq_timer {
/* ... tempo / offset / running state */
unsigned int running:1, /* running state of queue */
initialized:1; /* timer is initialized */
unsigned int tempo; /* current tempo, us/tick */
int ppq; /* time resolution, ticks/quarter */
snd_seq_real_time_t cur_time; /* current time */
struct snd_seq_timer_tick tick; /* current tick */
int tick_updated;
int type; /* timer type */
struct snd_timer_id alsa_id; /* ALSA's timer ID */
struct snd_timer_instance *timeri; /* timer instance */
unsigned int ticks;
unsigned long preferred_resolution; /* timer resolution, ticks/sec */
unsigned int skew;
unsigned int skew_base;
unsigned int tempo_base;
struct timespec64 last_update; /* time of last clock update, used for interpolation */
spinlock_t lock;
};
/* create new timer (constructor) */
struct snd_seq_timer *snd_seq_timer_new(void);
/* delete timer (destructor) */
void snd_seq_timer_delete(struct snd_seq_timer **tmr);
/* */
static inline void snd_seq_timer_update_tick(struct snd_seq_timer_tick *tick,
unsigned long resolution)
{
if (tick->resolution > 0) {
tick->fraction += resolution;
tick->cur_tick += (unsigned int)(tick->fraction / tick->resolution);
tick->fraction %= tick->resolution;
}
}
/* compare timestamp between events */
/* return 1 if a >= b; otherwise return 0 */
static inline int snd_seq_compare_tick_time(snd_seq_tick_time_t *a, snd_seq_tick_time_t *b)
{
/* compare ticks */
return (*a >= *b);
}
static inline int snd_seq_compare_real_time(snd_seq_real_time_t *a, snd_seq_real_time_t *b)
{
/* compare real time */
if (a->tv_sec > b->tv_sec)
return 1;
if ((a->tv_sec == b->tv_sec) && (a->tv_nsec >= b->tv_nsec))
return 1;
return 0;
}
static inline void snd_seq_sanity_real_time(snd_seq_real_time_t *tm)
{
while (tm->tv_nsec >= 1000000000) {
/* roll-over */
tm->tv_nsec -= 1000000000;
tm->tv_sec++;
}
}
/* increment timestamp */
static inline void snd_seq_inc_real_time(snd_seq_real_time_t *tm, snd_seq_real_time_t *inc)
{
tm->tv_sec += inc->tv_sec;
tm->tv_nsec += inc->tv_nsec;
snd_seq_sanity_real_time(tm);
}
static inline void snd_seq_inc_time_nsec(snd_seq_real_time_t *tm, unsigned long nsec)
{
tm->tv_nsec += nsec;
snd_seq_sanity_real_time(tm);
}
/* called by timer isr */
struct snd_seq_queue;
int snd_seq_timer_open(struct snd_seq_queue *q);
int snd_seq_timer_close(struct snd_seq_queue *q);
void snd_seq_timer_defaults(struct snd_seq_timer *tmr);
void snd_seq_timer_reset(struct snd_seq_timer *tmr);
int snd_seq_timer_stop(struct snd_seq_timer *tmr);
int snd_seq_timer_start(struct snd_seq_timer *tmr);
int snd_seq_timer_continue(struct snd_seq_timer *tmr);
int snd_seq_timer_set_tempo(struct snd_seq_timer *tmr, int tempo);
int snd_seq_timer_set_tempo_ppq(struct snd_seq_timer *tmr, int tempo, int ppq,
unsigned int tempo_base);
int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, snd_seq_tick_time_t position);
int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, snd_seq_real_time_t position);
int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, unsigned int base);
snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr,
bool adjust_ktime);
snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr);
extern int seq_default_timer_class;
extern int seq_default_timer_sclass;
extern int seq_default_timer_card;
extern int seq_default_timer_device;
extern int seq_default_timer_subdevice;
extern int seq_default_timer_resolution;
#endif
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