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1/* SPDX-License-Identifier: GPL-2.0-or-later */2/*3 * ALSA sequencer Timer4 * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl>5 */6#ifndef __SND_SEQ_TIMER_H7#define __SND_SEQ_TIMER_H8 9#include <sound/timer.h>10#include <sound/seq_kernel.h>11 12struct snd_seq_timer_tick {13 snd_seq_tick_time_t cur_tick; /* current tick */14 unsigned long resolution; /* time per tick in nsec */15 unsigned long fraction; /* current time per tick in nsec */16};17 18struct snd_seq_timer {19 /* ... tempo / offset / running state */20 21 unsigned int running:1, /* running state of queue */ 22 initialized:1; /* timer is initialized */23 24 unsigned int tempo; /* current tempo, us/tick */25 int ppq; /* time resolution, ticks/quarter */26 27 snd_seq_real_time_t cur_time; /* current time */28 struct snd_seq_timer_tick tick; /* current tick */29 int tick_updated;30 31 int type; /* timer type */32 struct snd_timer_id alsa_id; /* ALSA's timer ID */33 struct snd_timer_instance *timeri; /* timer instance */34 unsigned int ticks;35 unsigned long preferred_resolution; /* timer resolution, ticks/sec */36 37 unsigned int skew;38 unsigned int skew_base;39 unsigned int tempo_base;40 41 struct timespec64 last_update; /* time of last clock update, used for interpolation */42 43 spinlock_t lock;44};45 46 47/* create new timer (constructor) */48struct snd_seq_timer *snd_seq_timer_new(void);49 50/* delete timer (destructor) */51void snd_seq_timer_delete(struct snd_seq_timer **tmr);52 53/* */54static inline void snd_seq_timer_update_tick(struct snd_seq_timer_tick *tick,55 unsigned long resolution)56{57 if (tick->resolution > 0) {58 tick->fraction += resolution;59 tick->cur_tick += (unsigned int)(tick->fraction / tick->resolution);60 tick->fraction %= tick->resolution;61 }62}63 64 65/* compare timestamp between events */66/* return 1 if a >= b; otherwise return 0 */67static inline int snd_seq_compare_tick_time(snd_seq_tick_time_t *a, snd_seq_tick_time_t *b)68{69 /* compare ticks */70 return (*a >= *b);71}72 73static inline int snd_seq_compare_real_time(snd_seq_real_time_t *a, snd_seq_real_time_t *b)74{75 /* compare real time */76 if (a->tv_sec > b->tv_sec)77 return 1;78 if ((a->tv_sec == b->tv_sec) && (a->tv_nsec >= b->tv_nsec))79 return 1;80 return 0;81}82 83 84static inline void snd_seq_sanity_real_time(snd_seq_real_time_t *tm)85{86 while (tm->tv_nsec >= 1000000000) {87 /* roll-over */88 tm->tv_nsec -= 1000000000;89 tm->tv_sec++;90 }91}92 93 94/* increment timestamp */95static inline void snd_seq_inc_real_time(snd_seq_real_time_t *tm, snd_seq_real_time_t *inc)96{97 tm->tv_sec += inc->tv_sec;98 tm->tv_nsec += inc->tv_nsec;99 snd_seq_sanity_real_time(tm);100}101 102static inline void snd_seq_inc_time_nsec(snd_seq_real_time_t *tm, unsigned long nsec)103{104 tm->tv_nsec += nsec;105 snd_seq_sanity_real_time(tm);106}107 108/* called by timer isr */109struct snd_seq_queue;110int snd_seq_timer_open(struct snd_seq_queue *q);111int snd_seq_timer_close(struct snd_seq_queue *q);112void snd_seq_timer_defaults(struct snd_seq_timer *tmr);113void snd_seq_timer_reset(struct snd_seq_timer *tmr);114int snd_seq_timer_stop(struct snd_seq_timer *tmr);115int snd_seq_timer_start(struct snd_seq_timer *tmr);116int snd_seq_timer_continue(struct snd_seq_timer *tmr);117int snd_seq_timer_set_tempo(struct snd_seq_timer *tmr, int tempo);118int snd_seq_timer_set_tempo_ppq(struct snd_seq_timer *tmr, int tempo, int ppq,119 unsigned int tempo_base);120int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, snd_seq_tick_time_t position);121int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, snd_seq_real_time_t position);122int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, unsigned int base);123snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr,124 bool adjust_ktime);125snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr);126 127extern int seq_default_timer_class;128extern int seq_default_timer_sclass;129extern int seq_default_timer_card;130extern int seq_default_timer_device;131extern int seq_default_timer_subdevice;132extern int seq_default_timer_resolution;133 134#endif135