/* 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_WORK     0x00000010      /* timer is called from work */

#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 work) */
#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 work_struct task_work;
        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 work */
        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 */