1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
2 | /* |
3 | * ALSA sequencer Timer |
4 | * Copyright (c) 1998-1999 by Frank van de Pol <fvdpol@coil.demon.nl> |
5 | */ |
6 | #ifndef __SND_SEQ_TIMER_H |
7 | #define __SND_SEQ_TIMER_H |
8 | |
9 | #include <sound/timer.h> |
10 | #include <sound/seq_kernel.h> |
11 | |
12 | struct 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 | |
18 | struct 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 | |
40 | struct timespec64 last_update; /* time of last clock update, used for interpolation */ |
41 | |
42 | spinlock_t lock; |
43 | }; |
44 | |
45 | |
46 | /* create new timer (constructor) */ |
47 | struct snd_seq_timer *snd_seq_timer_new(void); |
48 | |
49 | /* delete timer (destructor) */ |
50 | void snd_seq_timer_delete(struct snd_seq_timer **tmr); |
51 | |
52 | /* */ |
53 | static inline void snd_seq_timer_update_tick(struct snd_seq_timer_tick *tick, |
54 | unsigned long resolution) |
55 | { |
56 | if (tick->resolution > 0) { |
57 | tick->fraction += resolution; |
58 | tick->cur_tick += (unsigned int)(tick->fraction / tick->resolution); |
59 | tick->fraction %= tick->resolution; |
60 | } |
61 | } |
62 | |
63 | |
64 | /* compare timestamp between events */ |
65 | /* return 1 if a >= b; otherwise return 0 */ |
66 | static inline int snd_seq_compare_tick_time(snd_seq_tick_time_t *a, snd_seq_tick_time_t *b) |
67 | { |
68 | /* compare ticks */ |
69 | return (*a >= *b); |
70 | } |
71 | |
72 | static inline int snd_seq_compare_real_time(snd_seq_real_time_t *a, snd_seq_real_time_t *b) |
73 | { |
74 | /* compare real time */ |
75 | if (a->tv_sec > b->tv_sec) |
76 | return 1; |
77 | if ((a->tv_sec == b->tv_sec) && (a->tv_nsec >= b->tv_nsec)) |
78 | return 1; |
79 | return 0; |
80 | } |
81 | |
82 | |
83 | static inline void snd_seq_sanity_real_time(snd_seq_real_time_t *tm) |
84 | { |
85 | while (tm->tv_nsec >= 1000000000) { |
86 | /* roll-over */ |
87 | tm->tv_nsec -= 1000000000; |
88 | tm->tv_sec++; |
89 | } |
90 | } |
91 | |
92 | |
93 | /* increment timestamp */ |
94 | static inline void snd_seq_inc_real_time(snd_seq_real_time_t *tm, snd_seq_real_time_t *inc) |
95 | { |
96 | tm->tv_sec += inc->tv_sec; |
97 | tm->tv_nsec += inc->tv_nsec; |
98 | snd_seq_sanity_real_time(tm); |
99 | } |
100 | |
101 | static inline void snd_seq_inc_time_nsec(snd_seq_real_time_t *tm, unsigned long nsec) |
102 | { |
103 | tm->tv_nsec += nsec; |
104 | snd_seq_sanity_real_time(tm); |
105 | } |
106 | |
107 | /* called by timer isr */ |
108 | struct snd_seq_queue; |
109 | int snd_seq_timer_open(struct snd_seq_queue *q); |
110 | int snd_seq_timer_close(struct snd_seq_queue *q); |
111 | int snd_seq_timer_midi_open(struct snd_seq_queue *q); |
112 | int snd_seq_timer_midi_close(struct snd_seq_queue *q); |
113 | void snd_seq_timer_defaults(struct snd_seq_timer *tmr); |
114 | void snd_seq_timer_reset(struct snd_seq_timer *tmr); |
115 | int snd_seq_timer_stop(struct snd_seq_timer *tmr); |
116 | int snd_seq_timer_start(struct snd_seq_timer *tmr); |
117 | int snd_seq_timer_continue(struct snd_seq_timer *tmr); |
118 | int snd_seq_timer_set_tempo(struct snd_seq_timer *tmr, int tempo); |
119 | int snd_seq_timer_set_tempo_ppq(struct snd_seq_timer *tmr, int tempo, int ppq); |
120 | int snd_seq_timer_set_position_tick(struct snd_seq_timer *tmr, snd_seq_tick_time_t position); |
121 | int snd_seq_timer_set_position_time(struct snd_seq_timer *tmr, snd_seq_real_time_t position); |
122 | int snd_seq_timer_set_skew(struct snd_seq_timer *tmr, unsigned int skew, unsigned int base); |
123 | snd_seq_real_time_t snd_seq_timer_get_cur_time(struct snd_seq_timer *tmr, |
124 | bool adjust_ktime); |
125 | snd_seq_tick_time_t snd_seq_timer_get_cur_tick(struct snd_seq_timer *tmr); |
126 | |
127 | extern int seq_default_timer_class; |
128 | extern int seq_default_timer_sclass; |
129 | extern int seq_default_timer_card; |
130 | extern int seq_default_timer_device; |
131 | extern int seq_default_timer_subdevice; |
132 | extern int seq_default_timer_resolution; |
133 | |
134 | #endif |
135 | |