timer.h (5109B)
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 */