1 /* 2 * ALSA sequencer Timer 3 * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl> 4 * 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 * 20 */ 21 #ifndef __SND_SEQ_TIMER_H 22 #define __SND_SEQ_TIMER_H 23 24 #include <sound/timer.h> 25 #include <sound/seq_kernel.h> 26 27 struct snd_seq_timer_tick { 28 snd_seq_tick_time_t cur_tick; /* current tick */ 29 unsigned long resolution; /* time per tick in nsec */ 30 unsigned long fraction; /* current time per tick in nsec */ 31 }; 32 33 struct snd_seq_timer { 34 /* ... tempo / offset / running state */ 35 36 unsigned int running:1, /* running state of queue */ 37 initialized:1; /* timer is initialized */ 38 39 unsigned int tempo; /* current tempo, us/tick */ 40 int ppq; /* time resolution, ticks/quarter */ 41 42 snd_seq_real_time_t cur_time; /* current time */ 43 struct snd_seq_timer_tick tick; /* current tick */ 44 int tick_updated; 45 46 int type; /* timer type */ 47 struct snd_timer_id alsa_id; /* ALSA's timer ID */ 48 struct snd_timer_instance *timeri; /* timer instance */ 49 unsigned int ticks; 50 unsigned long preferred_resolution; /* timer resolution, ticks/sec */ 51 52 unsigned int skew; 53 unsigned int skew_base; 54 55 struct timespec64 last_update; /* time of last clock update, used for interpolation */ 56 57 spinlock_t lock; 58 }; 59 60 61 /* create new timer (constructor) */ 62 struct snd_seq_timer *snd_seq_timer_new(void); 63 64 /* delete timer (destructor) */ 65 void snd_seq_timer_delete(struct snd_seq_timer **tmr); 66 67 /* */ 68 static inline void snd_seq_timer_update_tick(struct snd_seq_timer_tick *tick, 69 unsigned long resolution) 70 { 71 if (tick->resolution > 0) { 72 tick->fraction += resolution; 73 tick->cur_tick += (unsigned int)(tick->fraction / tick->resolution); 74 tick->fraction %= tick->resolution; 75 } 76 } 77 78 79 /* compare timestamp between events */ 80 /* return 1 if a >= b; otherwise return 0 */ 81 static inline int snd_seq_compare_tick_time(snd_seq_tick_time_t *a, snd_seq_tick_time_t *b) 82 { 83 /* compare ticks */ 84 return (*a >= *b); 85 } 86 87 static inline int snd_seq_compare_real_time(snd_seq_real_time_t *a, snd_seq_real_time_t *b) 88 { 89 /* compare real time */ 90 if (a->tv_sec > b->tv_sec) 91 return 1; 92 if ((a->tv_sec == b->tv_sec) && (a->tv_nsec >= b->tv_nsec)) 93 return 1; 94 return 0; 95 } 96 97 98 static inline void snd_seq_sanity_real_time(snd_seq_real_time_t *tm) 99 { 100 while (tm->tv_nsec >= 1000000000) { 101 /* roll-over */ 102 tm->tv_nsec -= 1000000000; 103 tm->tv_sec++; 104 } 105 } 106 107 108 /* increment timestamp */ 109 static inline void snd_seq_inc_real_time(snd_seq_real_time_t *tm, snd_seq_real_time_t *inc) 110 { 111 tm->tv_sec += inc->tv_sec; 112 tm->tv_nsec += inc->tv_nsec; 113 snd_seq_sanity_real_time(tm); 114 } 115 116 static inline void snd_seq_inc_time_nsec(snd_seq_real_time_t *tm, unsigned long nsec) 117 { 118 tm->tv_nsec += nsec; 119 snd_seq_sanity_real_time(tm); 120 } 121 122 /* called by timer isr */ 123 struct snd_seq_queue; 124 int snd_seq_timer_open(struct snd_seq_queue *q); 125 int snd_seq_timer_close(struct snd_seq_queue *q); 126 int snd_seq_timer_midi_open(struct snd_seq_queue *q); 127 int snd_seq_timer_midi_close(struct snd_seq_queue *q); 128 void snd_seq_timer_defaults(struct snd_seq_timer *tmr); 129 void snd_seq_timer_reset(struct snd_seq_timer *tmr); 130 int snd_seq_timer_stop(struct snd_seq_timer *tmr); 131 int snd_seq_timer_start(struct snd_seq_timer *tmr); 132 int snd_seq_timer_continue(struct snd_seq_timer *tmr); 133 int snd_seq_timer_set_tempo(struct snd_seq_timer *tmr, int tempo); 134 int snd_seq_timer_set_ppq(struct snd_seq_timer *tmr, int ppq); 135 int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, snd_seq_tick_time_t position); 136 int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, snd_seq_real_time_t position); 137 int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, unsigned int base); 138 snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr); 139 snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr); 140 141 extern int seq_default_timer_class; 142 extern int seq_default_timer_sclass; 143 extern int seq_default_timer_card; 144 extern int seq_default_timer_device; 145 extern int seq_default_timer_subdevice; 146 extern int seq_default_timer_resolution; 147 148 #endif 149