1/* SPDX-License-Identifier: GPL-2.0-or-later */
2#ifndef __SOUND_TIMER_H
3#define __SOUND_TIMER_H
4
5/*
6 * Timer abstract layer
7 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>,
8 * Abramo Bagnara <abramo@alsa-project.org>
9 */
10
11#include <sound/asound.h>
12#include <linux/interrupt.h>
13
14#define snd_timer_chip(timer) ((timer)->private_data)
15
16#define SNDRV_TIMER_DEVICES 16
17
18#define SNDRV_TIMER_DEV_FLG_PCM 0x10000000
19
20#define SNDRV_TIMER_HW_AUTO 0x00000001 /* auto trigger is supported */
21#define SNDRV_TIMER_HW_STOP 0x00000002 /* call stop before start */
22#define SNDRV_TIMER_HW_SLAVE 0x00000004 /* only slave timer (variable resolution) */
23#define SNDRV_TIMER_HW_FIRST 0x00000008 /* first tick can be incomplete */
24#define SNDRV_TIMER_HW_WORK 0x00000010 /* timer is called from work */
25
26#define SNDRV_TIMER_IFLG_SLAVE 0x00000001
27#define SNDRV_TIMER_IFLG_RUNNING 0x00000002
28#define SNDRV_TIMER_IFLG_START 0x00000004
29#define SNDRV_TIMER_IFLG_AUTO 0x00000008 /* auto restart */
30#define SNDRV_TIMER_IFLG_FAST 0x00000010 /* fast callback (do not use work) */
31#define SNDRV_TIMER_IFLG_CALLBACK 0x00000020 /* timer callback is active */
32#define SNDRV_TIMER_IFLG_EXCLUSIVE 0x00000040 /* exclusive owner - no more instances */
33#define SNDRV_TIMER_IFLG_EARLY_EVENT 0x00000080 /* write early event to the poll queue */
34
35#define SNDRV_TIMER_FLG_CHANGE 0x00000001
36#define SNDRV_TIMER_FLG_RESCHED 0x00000002 /* need reschedule */
37
38struct snd_timer;
39
40struct snd_timer_hardware {
41 /* -- must be filled with low-level driver */
42 unsigned int flags; /* various flags */
43 unsigned long resolution; /* average timer resolution for one tick in nsec */
44 unsigned long resolution_min; /* minimal resolution */
45 unsigned long resolution_max; /* maximal resolution */
46 unsigned long ticks; /* max timer ticks per interrupt */
47 /* -- low-level functions -- */
48 int (*open) (struct snd_timer * timer);
49 int (*close) (struct snd_timer * timer);
50 unsigned long (*c_resolution) (struct snd_timer * timer);
51 int (*start) (struct snd_timer * timer);
52 int (*stop) (struct snd_timer * timer);
53 int (*set_period) (struct snd_timer * timer, unsigned long period_num, unsigned long period_den);
54 int (*precise_resolution) (struct snd_timer * timer, unsigned long *num, unsigned long *den);
55};
56
57struct snd_timer {
58 int tmr_class;
59 struct snd_card *card;
60 struct module *module;
61 int tmr_device;
62 int tmr_subdevice;
63 char id[64];
64 char name[80];
65 unsigned int flags;
66 int running; /* running instances */
67 unsigned long sticks; /* schedule ticks */
68 void *private_data;
69 void (*private_free) (struct snd_timer *timer);
70 struct snd_timer_hardware hw;
71 spinlock_t lock;
72 struct list_head device_list;
73 struct list_head open_list_head;
74 struct list_head active_list_head;
75 struct list_head ack_list_head;
76 struct list_head sack_list_head; /* slow ack list head */
77 struct work_struct task_work;
78 int max_instances; /* upper limit of timer instances */
79 int num_instances; /* current number of timer instances */
80};
81
82struct snd_timer_instance {
83 struct snd_timer *timer;
84 char *owner;
85 unsigned int flags;
86 void *private_data;
87 void (*private_free) (struct snd_timer_instance *ti);
88 void (*callback) (struct snd_timer_instance *timeri,
89 unsigned long ticks, unsigned long resolution);
90 void (*ccallback) (struct snd_timer_instance * timeri,
91 int event,
92 struct timespec64 * tstamp,
93 unsigned long resolution);
94 void (*disconnect)(struct snd_timer_instance *timeri);
95 void *callback_data;
96 unsigned long ticks; /* auto-load ticks when expired */
97 unsigned long cticks; /* current ticks */
98 unsigned long pticks; /* accumulated ticks for callback */
99 unsigned long resolution; /* current resolution for work */
100 unsigned long lost; /* lost ticks */
101 int slave_class;
102 unsigned int slave_id;
103 struct list_head open_list;
104 struct list_head active_list;
105 struct list_head ack_list;
106 struct list_head slave_list_head;
107 struct list_head slave_active_head;
108 struct snd_timer_instance *master;
109};
110
111/*
112 * Registering
113 */
114
115int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid, struct snd_timer **rtimer);
116void snd_timer_notify(struct snd_timer *timer, int event, struct timespec64 *tstamp);
117int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer);
118int snd_timer_global_free(struct snd_timer *timer);
119int snd_timer_global_register(struct snd_timer *timer);
120
121struct snd_timer_instance *snd_timer_instance_new(const char *owner);
122void snd_timer_instance_free(struct snd_timer_instance *timeri);
123int snd_timer_open(struct snd_timer_instance *timeri, struct snd_timer_id *tid, unsigned int slave_id);
124void snd_timer_close(struct snd_timer_instance *timeri);
125unsigned long snd_timer_resolution(struct snd_timer_instance *timeri);
126int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks);
127int snd_timer_stop(struct snd_timer_instance *timeri);
128int snd_timer_continue(struct snd_timer_instance *timeri);
129int snd_timer_pause(struct snd_timer_instance *timeri);
130
131void snd_timer_interrupt(struct snd_timer *timer, unsigned long ticks_left);
132
133#endif /* __SOUND_TIMER_H */
134