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1/* SPDX-License-Identifier: GPL-2.0-or-later */2#ifndef __SOUND_TIMER_H3#define __SOUND_TIMER_H4 5/*6 * Timer abstract layer7 * 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 1617 18#define SNDRV_TIMER_DEV_FLG_PCM 0x1000000019 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 0x0000000127#define SNDRV_TIMER_IFLG_RUNNING 0x0000000228#define SNDRV_TIMER_IFLG_START 0x0000000429#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 0x0000000136#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 * Registering113 */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