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 /* */
snd_seq_timer_update_tick(struct snd_seq_timer_tick * tick,unsigned long resolution)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 */
snd_seq_compare_tick_time(snd_seq_tick_time_t * a,snd_seq_tick_time_t * b)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
snd_seq_compare_real_time(snd_seq_real_time_t * a,snd_seq_real_time_t * b)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
snd_seq_sanity_real_time(snd_seq_real_time_t * tm)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 */
snd_seq_inc_real_time(snd_seq_real_time_t * tm,snd_seq_real_time_t * inc)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
snd_seq_inc_time_nsec(snd_seq_real_time_t * tm,unsigned long nsec)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