/* SPDX-License-Identifier: GPL-2.0-or-later */ #ifndef __SOUND_TIMER_H #define __SOUND_TIMER_H /* * Timer abstract layer * Copyright (c) by Jaroslav Kysela <perex@perex.cz>, * Abramo Bagnara <abramo@alsa-project.org> */ #include <sound/asound.h> #include <linux/interrupt.h> #define snd_timer_chip(timer) ((timer)->private_data) #define SNDRV_TIMER_DEVICES 16 #define SNDRV_TIMER_DEV_FLG_PCM 0x10000000 #define SNDRV_TIMER_HW_AUTO 0x00000001 /* auto trigger is supported */ #define SNDRV_TIMER_HW_STOP 0x00000002 /* call stop before start */ #define SNDRV_TIMER_HW_SLAVE 0x00000004 /* only slave timer (variable resolution) */ #define SNDRV_TIMER_HW_FIRST 0x00000008 /* first tick can be incomplete */ #define SNDRV_TIMER_HW_TASKLET 0x00000010 /* timer is called from tasklet */ #define SNDRV_TIMER_IFLG_SLAVE 0x00000001 #define SNDRV_TIMER_IFLG_RUNNING 0x00000002 #define SNDRV_TIMER_IFLG_START 0x00000004 #define SNDRV_TIMER_IFLG_AUTO 0x00000008 /* auto restart */ #define SNDRV_TIMER_IFLG_FAST 0x00000010 /* fast callback (do not use tasklet) */ #define SNDRV_TIMER_IFLG_CALLBACK 0x00000020 /* timer callback is active */ #define SNDRV_TIMER_IFLG_EXCLUSIVE 0x00000040 /* exclusive owner - no more instances */ #define SNDRV_TIMER_IFLG_EARLY_EVENT 0x00000080 /* write early event to the poll queue */ #define SNDRV_TIMER_FLG_CHANGE 0x00000001 #define SNDRV_TIMER_FLG_RESCHED 0x00000002 /* need reschedule */ struct snd_timer; struct snd_timer_hardware { /* -- must be filled with low-level driver */ unsigned int flags; /* various flags */ unsigned long resolution; /* average timer resolution for one tick in nsec */ unsigned long resolution_min; /* minimal resolution */ unsigned long resolution_max; /* maximal resolution */ unsigned long ticks; /* max timer ticks per interrupt */ /* -- low-level functions -- */ int (*open) (struct snd_timer * timer); int (*close) (struct snd_timer * timer); unsigned long (*c_resolution) (struct snd_timer * timer); int (*start) (struct snd_timer * timer); int (*stop) (struct snd_timer * timer); int (*set_period) (struct snd_timer * timer, unsigned long period_num, unsigned long period_den); int (*precise_resolution) (struct snd_timer * timer, unsigned long *num, unsigned long *den); }; struct snd_timer { int tmr_class; struct snd_card *card; struct module *module; int tmr_device; int tmr_subdevice; char id[64]; char name[80]; unsigned int flags; int running; /* running instances */ unsigned long sticks; /* schedule ticks */ void *private_data; void (*private_free) (struct snd_timer *timer); struct snd_timer_hardware hw; spinlock_t lock; struct list_head device_list; struct list_head open_list_head; struct list_head active_list_head; struct list_head ack_list_head; struct list_head sack_list_head; /* slow ack list head */ struct tasklet_struct task_queue; int max_instances; /* upper limit of timer instances */ int num_instances; /* current number of timer instances */ }; struct snd_timer_instance { struct snd_timer *timer; char *owner; unsigned int flags; void *private_data; void (*private_free) (struct snd_timer_instance *ti); void (*callback) (struct snd_timer_instance *timeri, unsigned long ticks, unsigned long resolution); void (*ccallback) (struct snd_timer_instance * timeri, int event, struct timespec64 * tstamp, unsigned long resolution); void (*disconnect)(struct snd_timer_instance *timeri); void *callback_data; unsigned long ticks; /* auto-load ticks when expired */ unsigned long cticks; /* current ticks */ unsigned long pticks; /* accumulated ticks for callback */ unsigned long resolution; /* current resolution for tasklet */ unsigned long lost; /* lost ticks */ int slave_class; unsigned int slave_id; struct list_head open_list; struct list_head active_list; struct list_head ack_list; struct list_head slave_list_head; struct list_head slave_active_head; struct snd_timer_instance *master; }; /* * Registering */ int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid, struct snd_timer **rtimer); void snd_timer_notify(struct snd_timer *timer, int event, struct timespec64 *tstamp); int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer); int snd_timer_global_free(struct snd_timer *timer); int snd_timer_global_register(struct snd_timer *timer); struct snd_timer_instance *snd_timer_instance_new(const char *owner); void snd_timer_instance_free(struct snd_timer_instance *timeri); int snd_timer_open(struct snd_timer_instance *timeri, struct snd_timer_id *tid, unsigned int slave_id); void snd_timer_close(struct snd_timer_instance *timeri); unsigned long snd_timer_resolution(struct snd_timer_instance *timeri); int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks); int snd_timer_stop(struct snd_timer_instance *timeri); int snd_timer_continue(struct snd_timer_instance *timeri); int snd_timer_pause(struct snd_timer_instance *timeri); void snd_timer_interrupt(struct snd_timer *timer, unsigned long ticks_left); #endif /* __SOUND_TIMER_H */