/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef __SOUND_PCM_H
#define __SOUND_PCM_H

/*
 *  Digital Audio (PCM) abstract layer
 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
 *                   Abramo Bagnara <abramo@alsa-project.org>
 */

#include <sound/asound.h>
#include <sound/memalloc.h>
#include <sound/minors.h>
#include <linux/poll.h>
#include <linux/mm.h>
#include <linux/bitops.h>
#include <linux/pm_qos.h>
#include <linux/refcount.h>
#include <linux/uio.h>

#define snd_pcm_substream_chip(substream) ((substream)->private_data)
#define snd_pcm_chip(pcm) ((pcm)->private_data)

#if IS_ENABLED(CONFIG_SND_PCM_OSS)
#include <sound/pcm_oss.h>
#endif

/*
 *  Hardware (lowlevel) section
 */

struct snd_pcm_hardware {
        unsigned int info;              /* SNDRV_PCM_INFO_* */
        u64 formats;                    /* SNDRV_PCM_FMTBIT_* */
        u32 subformats;                 /* for S32_LE, SNDRV_PCM_SUBFMTBIT_* */
        unsigned int rates;             /* SNDRV_PCM_RATE_* */
        unsigned int rate_min;          /* min rate */
        unsigned int rate_max;          /* max rate */
        unsigned int channels_min;      /* min channels */
        unsigned int channels_max;      /* max channels */
        size_t buffer_bytes_max;        /* max buffer size */
        size_t period_bytes_min;        /* min period size */
        size_t period_bytes_max;        /* max period size */
        unsigned int periods_min;       /* min # of periods */
        unsigned int periods_max;       /* max # of periods */
        size_t fifo_size;               /* fifo size in bytes */
};

struct snd_pcm_status64;
struct snd_pcm_substream;

struct snd_pcm_audio_tstamp_config; /* definitions further down */
struct snd_pcm_audio_tstamp_report;

struct snd_pcm_ops {
        int (*open)(struct snd_pcm_substream *substream);
        int (*close)(struct snd_pcm_substream *substream);
        int (*ioctl)(struct snd_pcm_substream * substream,
                     unsigned int cmd, void *arg);
        int (*hw_params)(struct snd_pcm_substream *substream,
                         struct snd_pcm_hw_params *params);
        int (*hw_free)(struct snd_pcm_substream *substream);
        int (*prepare)(struct snd_pcm_substream *substream);
        int (*trigger)(struct snd_pcm_substream *substream, int cmd);
        int (*sync_stop)(struct snd_pcm_substream *substream);
        snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *substream);
        int (*get_time_info)(struct snd_pcm_substream *substream,
                        struct timespec64 *system_ts, struct timespec64 *audio_ts,
                        struct snd_pcm_audio_tstamp_config *audio_tstamp_config,
                        struct snd_pcm_audio_tstamp_report *audio_tstamp_report);
        int (*fill_silence)(struct snd_pcm_substream *substream, int channel,
                            unsigned long pos, unsigned long bytes);
        int (*copy)(struct snd_pcm_substream *substream, int channel,
                    unsigned long pos, struct iov_iter *iter, unsigned long bytes);
        struct page *(*page)(struct snd_pcm_substream *substream,
                             unsigned long offset);
        int (*mmap)(struct snd_pcm_substream *substream, struct vm_area_struct *vma);
        int (*ack)(struct snd_pcm_substream *substream);
};

/*
 *
 */

#if defined(CONFIG_SND_DYNAMIC_MINORS)
#define SNDRV_PCM_DEVICES       (SNDRV_OS_MINORS-2)
#else
#define SNDRV_PCM_DEVICES       8
#endif

#define SNDRV_PCM_IOCTL1_RESET          0
/* 1 is absent slot. */
#define SNDRV_PCM_IOCTL1_CHANNEL_INFO   2
/* 3 is absent slot. */
#define SNDRV_PCM_IOCTL1_FIFO_SIZE      4
#define SNDRV_PCM_IOCTL1_SYNC_ID        5

#define SNDRV_PCM_TRIGGER_STOP          0
#define SNDRV_PCM_TRIGGER_START         1
#define SNDRV_PCM_TRIGGER_PAUSE_PUSH    2
#define SNDRV_PCM_TRIGGER_PAUSE_RELEASE 3
#define SNDRV_PCM_TRIGGER_SUSPEND       4
#define SNDRV_PCM_TRIGGER_RESUME        5
#define SNDRV_PCM_TRIGGER_DRAIN         6

#define SNDRV_PCM_POS_XRUN              ((snd_pcm_uframes_t)-1)

/* If you change this don't forget to change rates[] table in pcm_native.c */
#define SNDRV_PCM_RATE_5512             (1U<<0)         /* 5512Hz */
#define SNDRV_PCM_RATE_8000             (1U<<1)         /* 8000Hz */
#define SNDRV_PCM_RATE_11025            (1U<<2)         /* 11025Hz */
#define SNDRV_PCM_RATE_16000            (1U<<3)         /* 16000Hz */
#define SNDRV_PCM_RATE_22050            (1U<<4)         /* 22050Hz */
#define SNDRV_PCM_RATE_32000            (1U<<5)         /* 32000Hz */
#define SNDRV_PCM_RATE_44100            (1U<<6)         /* 44100Hz */
#define SNDRV_PCM_RATE_48000            (1U<<7)         /* 48000Hz */
#define SNDRV_PCM_RATE_64000            (1U<<8)         /* 64000Hz */
#define SNDRV_PCM_RATE_88200            (1U<<9)         /* 88200Hz */
#define SNDRV_PCM_RATE_96000            (1U<<10)        /* 96000Hz */
#define SNDRV_PCM_RATE_176400           (1U<<11)        /* 176400Hz */
#define SNDRV_PCM_RATE_192000           (1U<<12)        /* 192000Hz */
#define SNDRV_PCM_RATE_352800           (1U<<13)        /* 352800Hz */
#define SNDRV_PCM_RATE_384000           (1U<<14)        /* 384000Hz */
#define SNDRV_PCM_RATE_705600           (1U<<15)        /* 705600Hz */
#define SNDRV_PCM_RATE_768000           (1U<<16)        /* 768000Hz */
/* extended rates since 6.12 */
#define SNDRV_PCM_RATE_12000            (1U<<17)        /* 12000Hz */
#define SNDRV_PCM_RATE_24000            (1U<<18)        /* 24000Hz */
#define SNDRV_PCM_RATE_128000           (1U<<19)        /* 128000Hz */

#define SNDRV_PCM_RATE_CONTINUOUS       (1U<<30)        /* continuous range */
#define SNDRV_PCM_RATE_KNOT             (1U<<31)        /* supports more non-continuous rates */

#define SNDRV_PCM_RATE_8000_44100       (SNDRV_PCM_RATE_8000|SNDRV_PCM_RATE_11025|\
                                         SNDRV_PCM_RATE_16000|SNDRV_PCM_RATE_22050|\
                                         SNDRV_PCM_RATE_32000|SNDRV_PCM_RATE_44100)
#define SNDRV_PCM_RATE_8000_48000       (SNDRV_PCM_RATE_8000_44100|SNDRV_PCM_RATE_48000)
#define SNDRV_PCM_RATE_8000_96000       (SNDRV_PCM_RATE_8000_48000|SNDRV_PCM_RATE_64000|\
                                         SNDRV_PCM_RATE_88200|SNDRV_PCM_RATE_96000)
#define SNDRV_PCM_RATE_8000_192000      (SNDRV_PCM_RATE_8000_96000|SNDRV_PCM_RATE_176400|\
                                         SNDRV_PCM_RATE_192000)
#define SNDRV_PCM_RATE_8000_384000      (SNDRV_PCM_RATE_8000_192000|\
                                         SNDRV_PCM_RATE_352800|\
                                         SNDRV_PCM_RATE_384000)
#define SNDRV_PCM_RATE_8000_768000      (SNDRV_PCM_RATE_8000_384000|\
                                         SNDRV_PCM_RATE_705600|\
                                         SNDRV_PCM_RATE_768000)
#define _SNDRV_PCM_FMTBIT(fmt)          (1ULL << (__force int)SNDRV_PCM_FORMAT_##fmt)
#define SNDRV_PCM_FMTBIT_S8             _SNDRV_PCM_FMTBIT(S8)
#define SNDRV_PCM_FMTBIT_U8             _SNDRV_PCM_FMTBIT(U8)
#define SNDRV_PCM_FMTBIT_S16_LE         _SNDRV_PCM_FMTBIT(S16_LE)
#define SNDRV_PCM_FMTBIT_S16_BE         _SNDRV_PCM_FMTBIT(S16_BE)
#define SNDRV_PCM_FMTBIT_U16_LE         _SNDRV_PCM_FMTBIT(U16_LE)
#define SNDRV_PCM_FMTBIT_U16_BE         _SNDRV_PCM_FMTBIT(U16_BE)
#define SNDRV_PCM_FMTBIT_S24_LE         _SNDRV_PCM_FMTBIT(S24_LE)
#define SNDRV_PCM_FMTBIT_S24_BE         _SNDRV_PCM_FMTBIT(S24_BE)
#define SNDRV_PCM_FMTBIT_U24_LE         _SNDRV_PCM_FMTBIT(U24_LE)
#define SNDRV_PCM_FMTBIT_U24_BE         _SNDRV_PCM_FMTBIT(U24_BE)
// For S32/U32 formats, 'msbits' hardware parameter is often used to deliver information about the
// available bit count in most significant bit. It's for the case of so-called 'left-justified' or
// `right-padding` sample which has less width than 32 bit.
#define SNDRV_PCM_FMTBIT_S32_LE         _SNDRV_PCM_FMTBIT(S32_LE)
#define SNDRV_PCM_FMTBIT_S32_BE         _SNDRV_PCM_FMTBIT(S32_BE)
#define SNDRV_PCM_FMTBIT_U32_LE         _SNDRV_PCM_FMTBIT(U32_LE)
#define SNDRV_PCM_FMTBIT_U32_BE         _SNDRV_PCM_FMTBIT(U32_BE)
#define SNDRV_PCM_FMTBIT_FLOAT_LE       _SNDRV_PCM_FMTBIT(FLOAT_LE)
#define SNDRV_PCM_FMTBIT_FLOAT_BE       _SNDRV_PCM_FMTBIT(FLOAT_BE)
#define SNDRV_PCM_FMTBIT_FLOAT64_LE     _SNDRV_PCM_FMTBIT(FLOAT64_LE)
#define SNDRV_PCM_FMTBIT_FLOAT64_BE     _SNDRV_PCM_FMTBIT(FLOAT64_BE)
#define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE _SNDRV_PCM_FMTBIT(IEC958_SUBFRAME_LE)
#define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE _SNDRV_PCM_FMTBIT(IEC958_SUBFRAME_BE)
#define SNDRV_PCM_FMTBIT_MU_LAW         _SNDRV_PCM_FMTBIT(MU_LAW)
#define SNDRV_PCM_FMTBIT_A_LAW          _SNDRV_PCM_FMTBIT(A_LAW)
#define SNDRV_PCM_FMTBIT_IMA_ADPCM      _SNDRV_PCM_FMTBIT(IMA_ADPCM)
#define SNDRV_PCM_FMTBIT_MPEG           _SNDRV_PCM_FMTBIT(MPEG)
#define SNDRV_PCM_FMTBIT_GSM            _SNDRV_PCM_FMTBIT(GSM)
#define SNDRV_PCM_FMTBIT_S20_LE _SNDRV_PCM_FMTBIT(S20_LE)
#define SNDRV_PCM_FMTBIT_U20_LE _SNDRV_PCM_FMTBIT(U20_LE)
#define SNDRV_PCM_FMTBIT_S20_BE _SNDRV_PCM_FMTBIT(S20_BE)
#define SNDRV_PCM_FMTBIT_U20_BE _SNDRV_PCM_FMTBIT(U20_BE)
#define SNDRV_PCM_FMTBIT_SPECIAL        _SNDRV_PCM_FMTBIT(SPECIAL)
#define SNDRV_PCM_FMTBIT_S24_3LE        _SNDRV_PCM_FMTBIT(S24_3LE)
#define SNDRV_PCM_FMTBIT_U24_3LE        _SNDRV_PCM_FMTBIT(U24_3LE)
#define SNDRV_PCM_FMTBIT_S24_3BE        _SNDRV_PCM_FMTBIT(S24_3BE)
#define SNDRV_PCM_FMTBIT_U24_3BE        _SNDRV_PCM_FMTBIT(U24_3BE)
#define SNDRV_PCM_FMTBIT_S20_3LE        _SNDRV_PCM_FMTBIT(S20_3LE)
#define SNDRV_PCM_FMTBIT_U20_3LE        _SNDRV_PCM_FMTBIT(U20_3LE)
#define SNDRV_PCM_FMTBIT_S20_3BE        _SNDRV_PCM_FMTBIT(S20_3BE)
#define SNDRV_PCM_FMTBIT_U20_3BE        _SNDRV_PCM_FMTBIT(U20_3BE)
#define SNDRV_PCM_FMTBIT_S18_3LE        _SNDRV_PCM_FMTBIT(S18_3LE)
#define SNDRV_PCM_FMTBIT_U18_3LE        _SNDRV_PCM_FMTBIT(U18_3LE)
#define SNDRV_PCM_FMTBIT_S18_3BE        _SNDRV_PCM_FMTBIT(S18_3BE)
#define SNDRV_PCM_FMTBIT_U18_3BE        _SNDRV_PCM_FMTBIT(U18_3BE)
#define SNDRV_PCM_FMTBIT_G723_24        _SNDRV_PCM_FMTBIT(G723_24)
#define SNDRV_PCM_FMTBIT_G723_24_1B     _SNDRV_PCM_FMTBIT(G723_24_1B)
#define SNDRV_PCM_FMTBIT_G723_40        _SNDRV_PCM_FMTBIT(G723_40)
#define SNDRV_PCM_FMTBIT_G723_40_1B     _SNDRV_PCM_FMTBIT(G723_40_1B)
#define SNDRV_PCM_FMTBIT_DSD_U8         _SNDRV_PCM_FMTBIT(DSD_U8)
#define SNDRV_PCM_FMTBIT_DSD_U16_LE     _SNDRV_PCM_FMTBIT(DSD_U16_LE)
#define SNDRV_PCM_FMTBIT_DSD_U32_LE     _SNDRV_PCM_FMTBIT(DSD_U32_LE)
#define SNDRV_PCM_FMTBIT_DSD_U16_BE     _SNDRV_PCM_FMTBIT(DSD_U16_BE)
#define SNDRV_PCM_FMTBIT_DSD_U32_BE     _SNDRV_PCM_FMTBIT(DSD_U32_BE)

#ifdef SNDRV_LITTLE_ENDIAN
#define SNDRV_PCM_FMTBIT_S16            SNDRV_PCM_FMTBIT_S16_LE
#define SNDRV_PCM_FMTBIT_U16            SNDRV_PCM_FMTBIT_U16_LE
#define SNDRV_PCM_FMTBIT_S24            SNDRV_PCM_FMTBIT_S24_LE
#define SNDRV_PCM_FMTBIT_U24            SNDRV_PCM_FMTBIT_U24_LE
#define SNDRV_PCM_FMTBIT_S32            SNDRV_PCM_FMTBIT_S32_LE
#define SNDRV_PCM_FMTBIT_U32            SNDRV_PCM_FMTBIT_U32_LE
#define SNDRV_PCM_FMTBIT_FLOAT          SNDRV_PCM_FMTBIT_FLOAT_LE
#define SNDRV_PCM_FMTBIT_FLOAT64        SNDRV_PCM_FMTBIT_FLOAT64_LE
#define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE
#define SNDRV_PCM_FMTBIT_S20            SNDRV_PCM_FMTBIT_S20_LE
#define SNDRV_PCM_FMTBIT_U20            SNDRV_PCM_FMTBIT_U20_LE
#endif
#ifdef SNDRV_BIG_ENDIAN
#define SNDRV_PCM_FMTBIT_S16            SNDRV_PCM_FMTBIT_S16_BE
#define SNDRV_PCM_FMTBIT_U16            SNDRV_PCM_FMTBIT_U16_BE
#define SNDRV_PCM_FMTBIT_S24            SNDRV_PCM_FMTBIT_S24_BE
#define SNDRV_PCM_FMTBIT_U24            SNDRV_PCM_FMTBIT_U24_BE
#define SNDRV_PCM_FMTBIT_S32            SNDRV_PCM_FMTBIT_S32_BE
#define SNDRV_PCM_FMTBIT_U32            SNDRV_PCM_FMTBIT_U32_BE
#define SNDRV_PCM_FMTBIT_FLOAT          SNDRV_PCM_FMTBIT_FLOAT_BE
#define SNDRV_PCM_FMTBIT_FLOAT64        SNDRV_PCM_FMTBIT_FLOAT64_BE
#define SNDRV_PCM_FMTBIT_IEC958_SUBFRAME SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_BE
#define SNDRV_PCM_FMTBIT_S20            SNDRV_PCM_FMTBIT_S20_BE
#define SNDRV_PCM_FMTBIT_U20            SNDRV_PCM_FMTBIT_U20_BE
#endif

#define _SNDRV_PCM_SUBFMTBIT(fmt)       BIT((__force int)SNDRV_PCM_SUBFORMAT_##fmt)
#define SNDRV_PCM_SUBFMTBIT_STD         _SNDRV_PCM_SUBFMTBIT(STD)
#define SNDRV_PCM_SUBFMTBIT_MSBITS_MAX  _SNDRV_PCM_SUBFMTBIT(MSBITS_MAX)
#define SNDRV_PCM_SUBFMTBIT_MSBITS_20   _SNDRV_PCM_SUBFMTBIT(MSBITS_20)
#define SNDRV_PCM_SUBFMTBIT_MSBITS_24   _SNDRV_PCM_SUBFMTBIT(MSBITS_24)

struct snd_pcm_file {
        struct snd_pcm_substream *substream;
        int no_compat_mmap;
        unsigned int user_pversion;     /* supported protocol version */
};

struct snd_pcm_hw_rule;
typedef int (*snd_pcm_hw_rule_func_t)(struct snd_pcm_hw_params *params,
                                      struct snd_pcm_hw_rule *rule);

struct snd_pcm_hw_rule {
        unsigned int cond;
        int var;
        int deps[5];

        snd_pcm_hw_rule_func_t func;
        void *private;
};

struct snd_pcm_hw_constraints {
        struct snd_mask masks[SNDRV_PCM_HW_PARAM_LAST_MASK - 
                         SNDRV_PCM_HW_PARAM_FIRST_MASK + 1];
        struct snd_interval intervals[SNDRV_PCM_HW_PARAM_LAST_INTERVAL -
                             SNDRV_PCM_HW_PARAM_FIRST_INTERVAL + 1];
        unsigned int rules_num;
        unsigned int rules_all;
        struct snd_pcm_hw_rule *rules;
};

static inline struct snd_mask *constrs_mask(struct snd_pcm_hw_constraints *constrs,
                                            snd_pcm_hw_param_t var)
{
        return &constrs->masks[var - SNDRV_PCM_HW_PARAM_FIRST_MASK];
}

static inline struct snd_interval *constrs_interval(struct snd_pcm_hw_constraints *constrs,
                                                    snd_pcm_hw_param_t var)
{
        return &constrs->intervals[var - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL];
}

struct snd_ratnum {
        unsigned int num;
        unsigned int den_min, den_max, den_step;
};

struct snd_ratden {
        unsigned int num_min, num_max, num_step;
        unsigned int den;
};

struct snd_pcm_hw_constraint_ratnums {
        int nrats;
        const struct snd_ratnum *rats;
};

struct snd_pcm_hw_constraint_ratdens {
        int nrats;
        const struct snd_ratden *rats;
};

struct snd_pcm_hw_constraint_list {
        const unsigned int *list;
        unsigned int count;
        unsigned int mask;
};

struct snd_pcm_hw_constraint_ranges {
        unsigned int count;
        const struct snd_interval *ranges;
        unsigned int mask;
};

/*
 * userspace-provided audio timestamp config to kernel,
 * structure is for internal use only and filled with dedicated unpack routine
 */
struct snd_pcm_audio_tstamp_config {
        /* 5 of max 16 bits used */
        u32 type_requested:4;
        u32 report_delay:1; /* add total delay to A/D or D/A */
};

static inline void snd_pcm_unpack_audio_tstamp_config(__u32 data,
                                                struct snd_pcm_audio_tstamp_config *config)
{
        config->type_requested = data & 0xF;
        config->report_delay = (data >> 4) & 1;
}

/*
 * kernel-provided audio timestamp report to user-space
 * structure is for internal use only and read by dedicated pack routine
 */
struct snd_pcm_audio_tstamp_report {
        /* 6 of max 16 bits used for bit-fields */

        /* for backwards compatibility */
        u32 valid:1;

        /* actual type if hardware could not support requested timestamp */
        u32 actual_type:4;

        /* accuracy represented in ns units */
        u32 accuracy_report:1; /* 0 if accuracy unknown, 1 if accuracy field is valid */
        u32 accuracy; /* up to 4.29s, will be packed in separate field  */
};

static inline void snd_pcm_pack_audio_tstamp_report(__u32 *data, __u32 *accuracy,
                                                const struct snd_pcm_audio_tstamp_report *report)
{
        u32 tmp;

        tmp = report->accuracy_report;
        tmp <<= 4;
        tmp |= report->actual_type;
        tmp <<= 1;
        tmp |= report->valid;

        *data &= 0xffff; /* zero-clear MSBs */
        *data |= (tmp << 16);
        *accuracy = report->accuracy;
}


struct snd_pcm_runtime {
        /* -- Status -- */
        snd_pcm_state_t state;          /* stream state */
        snd_pcm_state_t suspended_state; /* suspended stream state */
        struct snd_pcm_substream *trigger_master;
        struct timespec64 trigger_tstamp;       /* trigger timestamp */
        bool trigger_tstamp_latched;     /* trigger timestamp latched in low-level driver/hardware */
        int overrange;
        snd_pcm_uframes_t avail_max;
        snd_pcm_uframes_t hw_ptr_base;  /* Position at buffer restart */
        snd_pcm_uframes_t hw_ptr_interrupt; /* Position at interrupt time */
        unsigned long hw_ptr_jiffies;   /* Time when hw_ptr is updated */
        unsigned long hw_ptr_buffer_jiffies; /* buffer time in jiffies */
        snd_pcm_sframes_t delay;        /* extra delay; typically FIFO size */
        u64 hw_ptr_wrap;                /* offset for hw_ptr due to boundary wrap-around */

        /* -- HW params -- */
        snd_pcm_access_t access;        /* access mode */
        snd_pcm_format_t format;        /* SNDRV_PCM_FORMAT_* */
        snd_pcm_subformat_t subformat;  /* subformat */
        unsigned int rate;              /* rate in Hz */
        unsigned int channels;          /* channels */
        snd_pcm_uframes_t period_size;  /* period size */
        unsigned int periods;           /* periods */
        snd_pcm_uframes_t buffer_size;  /* buffer size */
        snd_pcm_uframes_t min_align;    /* Min alignment for the format */
        size_t byte_align;
        unsigned int frame_bits;
        unsigned int sample_bits;
        unsigned int info;
        unsigned int rate_num;
        unsigned int rate_den;
        unsigned int no_period_wakeup: 1;

        /* -- SW params; see struct snd_pcm_sw_params for comments -- */
        int tstamp_mode;
        unsigned int period_step;
        snd_pcm_uframes_t start_threshold;
        snd_pcm_uframes_t stop_threshold;
        snd_pcm_uframes_t silence_threshold;
        snd_pcm_uframes_t silence_size;
        snd_pcm_uframes_t boundary;

        /* internal data of auto-silencer */
        snd_pcm_uframes_t silence_start; /* starting pointer to silence area */
        snd_pcm_uframes_t silence_filled; /* already filled part of silence area */

        bool std_sync_id;               /* hardware synchronization - standard per card ID */

        /* -- mmap -- */
        struct snd_pcm_mmap_status *status;
        struct snd_pcm_mmap_control *control;

        /* -- locking / scheduling -- */
        snd_pcm_uframes_t twake;        /* do transfer (!poll) wakeup if non-zero */
        wait_queue_head_t sleep;        /* poll sleep */
        wait_queue_head_t tsleep;       /* transfer sleep */
        struct snd_fasync *fasync;
        bool stop_operating;            /* sync_stop will be called */
        struct mutex buffer_mutex;      /* protect for buffer changes */
        atomic_t buffer_accessing;      /* >0: in r/w operation, <0: blocked */

        /* -- private section -- */
        void *private_data;
        void (*private_free)(struct snd_pcm_runtime *runtime);

        /* -- hardware description -- */
        struct snd_pcm_hardware hw;
        struct snd_pcm_hw_constraints hw_constraints;

        /* -- timer -- */
        unsigned int timer_resolution;  /* timer resolution */
        int tstamp_type;                /* timestamp type */

        /* -- DMA -- */           
        unsigned char *dma_area;        /* DMA area */
        dma_addr_t dma_addr;            /* physical bus address (not accessible from main CPU) */
        size_t dma_bytes;               /* size of DMA area */

        struct snd_dma_buffer *dma_buffer_p;    /* allocated buffer */
        unsigned int buffer_changed:1;  /* buffer allocation changed; set only in managed mode */

        /* -- audio timestamp config -- */
        struct snd_pcm_audio_tstamp_config audio_tstamp_config;
        struct snd_pcm_audio_tstamp_report audio_tstamp_report;
        struct timespec64 driver_tstamp;

#if IS_ENABLED(CONFIG_SND_PCM_OSS)
        /* -- OSS things -- */
        struct snd_pcm_oss_runtime oss;
#endif
};

struct snd_pcm_group {          /* keep linked substreams */
        spinlock_t lock;
        struct mutex mutex;
        struct list_head substreams;
        refcount_t refs;
};

struct pid;

struct snd_pcm_substream {
        struct snd_pcm *pcm;
        struct snd_pcm_str *pstr;
        void *private_data;             /* copied from pcm->private_data */
        int number;
        char name[32];                  /* substream name */
        int stream;                     /* stream (direction) */
        struct pm_qos_request latency_pm_qos_req; /* pm_qos request */
        size_t buffer_bytes_max;        /* limit ring buffer size */
        struct snd_dma_buffer dma_buffer;
        size_t dma_max;
        /* -- hardware operations -- */
        const struct snd_pcm_ops *ops;
        /* -- runtime information -- */
        struct snd_pcm_runtime *runtime;
        /* -- timer section -- */
        struct snd_timer *timer;                /* timer */
        unsigned timer_running: 1;      /* time is running */
        long wait_time; /* time in ms for R/W to wait for avail */
        /* -- next substream -- */
        struct snd_pcm_substream *next;
        /* -- linked substreams -- */
        struct list_head link_list;     /* linked list member */
        struct snd_pcm_group self_group;        /* fake group for non linked substream (with substream lock inside) */
        struct snd_pcm_group *group;            /* pointer to current group */
        /* -- assigned files -- */
        int ref_count;
        atomic_t mmap_count;
        unsigned int f_flags;
        void (*pcm_release)(struct snd_pcm_substream *);
        struct pid *pid;
#if IS_ENABLED(CONFIG_SND_PCM_OSS)
        /* -- OSS things -- */
        struct snd_pcm_oss_substream oss;
#endif
#ifdef CONFIG_SND_VERBOSE_PROCFS
        struct snd_info_entry *proc_root;
#endif /* CONFIG_SND_VERBOSE_PROCFS */
        /* misc flags */
        unsigned int hw_opened: 1;
        unsigned int managed_buffer_alloc:1;
#ifdef CONFIG_SND_PCM_XRUN_DEBUG
        unsigned int xrun_counter; /* number of times xrun happens */
#endif /* CONFIG_SND_PCM_XRUN_DEBUG */
};

#define SUBSTREAM_BUSY(substream) ((substream)->ref_count > 0)


struct snd_pcm_str {
        int stream;                             /* stream (direction) */
        struct snd_pcm *pcm;
        /* -- substreams -- */
        unsigned int substream_count;
        unsigned int substream_opened;
        struct snd_pcm_substream *substream;
#if IS_ENABLED(CONFIG_SND_PCM_OSS)
        /* -- OSS things -- */
        struct snd_pcm_oss_stream oss;
#endif
#ifdef CONFIG_SND_VERBOSE_PROCFS
        struct snd_info_entry *proc_root;
#ifdef CONFIG_SND_PCM_XRUN_DEBUG
        unsigned int xrun_debug;        /* 0 = disabled, 1 = verbose, 2 = stacktrace */
#endif
#endif
        struct snd_kcontrol *chmap_kctl; /* channel-mapping controls */
        struct device *dev;
};

struct snd_pcm {
        struct snd_card *card;
        struct list_head list;
        int device; /* device number */
        unsigned int info_flags;
        unsigned short dev_class;
        unsigned short dev_subclass;
        char id[64];
        char name[80];
        struct snd_pcm_str streams[2];
        struct mutex open_mutex;
        wait_queue_head_t open_wait;
        void *private_data;
        void (*private_free) (struct snd_pcm *pcm);
        bool internal; /* pcm is for internal use only */
        bool nonatomic; /* whole PCM operations are in non-atomic context */
        bool no_device_suspend; /* don't invoke device PM suspend */
#if IS_ENABLED(CONFIG_SND_PCM_OSS)
        struct snd_pcm_oss oss;
#endif
};

/*
 *  Registering
 */

extern const struct file_operations snd_pcm_f_ops[2];

int snd_pcm_new(struct snd_card *card, const char *id, int device,
                int playback_count, int capture_count,
                struct snd_pcm **rpcm);
int snd_pcm_new_internal(struct snd_card *card, const char *id, int device,
                int playback_count, int capture_count,
                struct snd_pcm **rpcm);
int snd_pcm_new_stream(struct snd_pcm *pcm, int stream, int substream_count);

#if IS_ENABLED(CONFIG_SND_PCM_OSS)
struct snd_pcm_notify {
        int (*n_register) (struct snd_pcm * pcm);
        int (*n_disconnect) (struct snd_pcm * pcm);
        int (*n_unregister) (struct snd_pcm * pcm);
        struct list_head list;
};
int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree);
#endif

/*
 *  Native I/O
 */

int snd_pcm_info(struct snd_pcm_substream *substream, struct snd_pcm_info *info);
int snd_pcm_info_user(struct snd_pcm_substream *substream,
                      struct snd_pcm_info __user *info);
int snd_pcm_status64(struct snd_pcm_substream *substream,
                     struct snd_pcm_status64 *status);
int snd_pcm_start(struct snd_pcm_substream *substream);
int snd_pcm_stop(struct snd_pcm_substream *substream, snd_pcm_state_t status);
int snd_pcm_drain_done(struct snd_pcm_substream *substream);
int snd_pcm_stop_xrun(struct snd_pcm_substream *substream);
#ifdef CONFIG_PM
int snd_pcm_suspend_all(struct snd_pcm *pcm);
#else
static inline int snd_pcm_suspend_all(struct snd_pcm *pcm)
{
        return 0;
}
#endif
int snd_pcm_kernel_ioctl(struct snd_pcm_substream *substream, unsigned int cmd, void *arg);
int snd_pcm_open_substream(struct snd_pcm *pcm, int stream, struct file *file,
                           struct snd_pcm_substream **rsubstream);
void snd_pcm_release_substream(struct snd_pcm_substream *substream);
int snd_pcm_attach_substream(struct snd_pcm *pcm, int stream, struct file *file,
                             struct snd_pcm_substream **rsubstream);
void snd_pcm_detach_substream(struct snd_pcm_substream *substream);
int snd_pcm_mmap_data(struct snd_pcm_substream *substream, struct file *file, struct vm_area_struct *area);


#ifdef CONFIG_SND_DEBUG
void snd_pcm_debug_name(struct snd_pcm_substream *substream,
                           char *name, size_t len);
#else
static inline void
snd_pcm_debug_name(struct snd_pcm_substream *substream, char *buf, size_t size)
{
        *buf = 0;
}
#endif

/*
 *  PCM library
 */

/**
 * snd_pcm_stream_linked - Check whether the substream is linked with others
 * @substream: substream to check
 *
 * Return: true if the given substream is being linked with others
 */
static inline int snd_pcm_stream_linked(struct snd_pcm_substream *substream)
{
        return substream->group != &substream->self_group;
}

void snd_pcm_stream_lock(struct snd_pcm_substream *substream);
void snd_pcm_stream_unlock(struct snd_pcm_substream *substream);
void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream);
void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream);
unsigned long _snd_pcm_stream_lock_irqsave(struct snd_pcm_substream *substream);
unsigned long _snd_pcm_stream_lock_irqsave_nested(struct snd_pcm_substream *substream);

/**
 * snd_pcm_stream_lock_irqsave - Lock the PCM stream
 * @substream: PCM substream
 * @flags: irq flags
 *
 * This locks the PCM stream like snd_pcm_stream_lock() but with the local
 * IRQ (only when nonatomic is false).  In nonatomic case, this is identical
 * as snd_pcm_stream_lock().
 */
#define snd_pcm_stream_lock_irqsave(substream, flags)            \
        do {                                                     \
                typecheck(unsigned long, flags);                 \
                flags = _snd_pcm_stream_lock_irqsave(substream); \
        } while (0)
void snd_pcm_stream_unlock_irqrestore(struct snd_pcm_substream *substream,
                                      unsigned long flags);

/**
 * snd_pcm_stream_lock_irqsave_nested - Single-nested PCM stream locking
 * @substream: PCM substream
 * @flags: irq flags
 *
 * This locks the PCM stream like snd_pcm_stream_lock_irqsave() but with
 * the single-depth lockdep subclass.
 */
#define snd_pcm_stream_lock_irqsave_nested(substream, flags)            \
        do {                                                            \
                typecheck(unsigned long, flags);                        \
                flags = _snd_pcm_stream_lock_irqsave_nested(substream); \
        } while (0)

/* definitions for guard(); use like guard(pcm_stream_lock) */
DEFINE_LOCK_GUARD_1(pcm_stream_lock, struct snd_pcm_substream,
                    snd_pcm_stream_lock(_T->lock),
                    snd_pcm_stream_unlock(_T->lock))
DEFINE_LOCK_GUARD_1(pcm_stream_lock_irq, struct snd_pcm_substream,
                    snd_pcm_stream_lock_irq(_T->lock),
                    snd_pcm_stream_unlock_irq(_T->lock))
DEFINE_LOCK_GUARD_1(pcm_stream_lock_irqsave, struct snd_pcm_substream,
                    snd_pcm_stream_lock_irqsave(_T->lock, _T->flags),
                    snd_pcm_stream_unlock_irqrestore(_T->lock, _T->flags),
                    unsigned long flags)

/**
 * snd_pcm_group_for_each_entry - iterate over the linked substreams
 * @s: the iterator
 * @substream: the substream
 *
 * Iterate over the all linked substreams to the given @substream.
 * When @substream isn't linked with any others, this gives returns @substream
 * itself once.
 */
#define snd_pcm_group_for_each_entry(s, substream) \
        list_for_each_entry(s, &substream->group->substreams, link_list)

#define for_each_pcm_streams(stream)                    \
        for (stream  = SNDRV_PCM_STREAM_PLAYBACK;       \
             stream <= SNDRV_PCM_STREAM_LAST;           \
             stream++)

/**
 * snd_pcm_running - Check whether the substream is in a running state
 * @substream: substream to check
 *
 * Return: true if the given substream is in the state RUNNING, or in the
 * state DRAINING for playback.
 */
static inline int snd_pcm_running(struct snd_pcm_substream *substream)
{
        return (substream->runtime->state == SNDRV_PCM_STATE_RUNNING ||
                (substream->runtime->state == SNDRV_PCM_STATE_DRAINING &&
                 substream->stream == SNDRV_PCM_STREAM_PLAYBACK));
}

/**
 * __snd_pcm_set_state - Change the current PCM state
 * @runtime: PCM runtime to set
 * @state: the current state to set
 *
 * Call within the stream lock
 */
static inline void __snd_pcm_set_state(struct snd_pcm_runtime *runtime,
                                       snd_pcm_state_t state)
{
        runtime->state = state;
        runtime->status->state = state; /* copy for mmap */
}

/**
 * bytes_to_samples - Unit conversion of the size from bytes to samples
 * @runtime: PCM runtime instance
 * @size: size in bytes
 *
 * Return: the size in samples
 */
static inline ssize_t bytes_to_samples(struct snd_pcm_runtime *runtime, ssize_t size)
{
        return size * 8 / runtime->sample_bits;
}

/**
 * bytes_to_frames - Unit conversion of the size from bytes to frames
 * @runtime: PCM runtime instance
 * @size: size in bytes
 *
 * Return: the size in frames
 */
static inline snd_pcm_sframes_t bytes_to_frames(struct snd_pcm_runtime *runtime, ssize_t size)
{
        return size * 8 / runtime->frame_bits;
}

/**
 * samples_to_bytes - Unit conversion of the size from samples to bytes
 * @runtime: PCM runtime instance
 * @size: size in samples
 *
 * Return: the byte size
 */
static inline ssize_t samples_to_bytes(struct snd_pcm_runtime *runtime, ssize_t size)
{
        return size * runtime->sample_bits / 8;
}

/**
 * frames_to_bytes - Unit conversion of the size from frames to bytes
 * @runtime: PCM runtime instance
 * @size: size in frames
 *
 * Return: the byte size
 */
static inline ssize_t frames_to_bytes(struct snd_pcm_runtime *runtime, snd_pcm_sframes_t size)
{
        return size * runtime->frame_bits / 8;
}

/**
 * frame_aligned - Check whether the byte size is aligned to frames
 * @runtime: PCM runtime instance
 * @bytes: size in bytes
 *
 * Return: true if aligned, or false if not
 */
static inline int frame_aligned(struct snd_pcm_runtime *runtime, ssize_t bytes)
{
        return bytes % runtime->byte_align == 0;
}

/**
 * snd_pcm_lib_buffer_bytes - Get the buffer size of the current PCM in bytes
 * @substream: PCM substream
 *
 * Return: buffer byte size
 */
static inline size_t snd_pcm_lib_buffer_bytes(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        return frames_to_bytes(runtime, runtime->buffer_size);
}

/**
 * snd_pcm_lib_period_bytes - Get the period size of the current PCM in bytes
 * @substream: PCM substream
 *
 * Return: period byte size
 */
static inline size_t snd_pcm_lib_period_bytes(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        return frames_to_bytes(runtime, runtime->period_size);
}

/**
 * snd_pcm_playback_avail - Get the available (writable) space for playback
 * @runtime: PCM runtime instance
 *
 * Result is between 0 ... (boundary - 1)
 *
 * Return: available frame size
 */
static inline snd_pcm_uframes_t snd_pcm_playback_avail(struct snd_pcm_runtime *runtime)
{
        snd_pcm_sframes_t avail = runtime->status->hw_ptr + runtime->buffer_size - runtime->control->appl_ptr;
        if (avail < 0)
                avail += runtime->boundary;
        else if ((snd_pcm_uframes_t) avail >= runtime->boundary)
                avail -= runtime->boundary;
        return avail;
}

/**
 * snd_pcm_capture_avail - Get the available (readable) space for capture
 * @runtime: PCM runtime instance
 *
 * Result is between 0 ... (boundary - 1)
 *
 * Return: available frame size
 */
static inline snd_pcm_uframes_t snd_pcm_capture_avail(struct snd_pcm_runtime *runtime)
{
        snd_pcm_sframes_t avail = runtime->status->hw_ptr - runtime->control->appl_ptr;
        if (avail < 0)
                avail += runtime->boundary;
        return avail;
}

/**
 * snd_pcm_playback_hw_avail - Get the queued space for playback
 * @runtime: PCM runtime instance
 *
 * Return: available frame size
 */
static inline snd_pcm_sframes_t snd_pcm_playback_hw_avail(struct snd_pcm_runtime *runtime)
{
        return runtime->buffer_size - snd_pcm_playback_avail(runtime);
}

/**
 * snd_pcm_capture_hw_avail - Get the free space for capture
 * @runtime: PCM runtime instance
 *
 * Return: available frame size
 */
static inline snd_pcm_sframes_t snd_pcm_capture_hw_avail(struct snd_pcm_runtime *runtime)
{
        return runtime->buffer_size - snd_pcm_capture_avail(runtime);
}

/**
 * snd_pcm_playback_ready - check whether the playback buffer is available
 * @substream: the pcm substream instance
 *
 * Checks whether enough free space is available on the playback buffer.
 *
 * Return: Non-zero if available, or zero if not.
 */
static inline int snd_pcm_playback_ready(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        return snd_pcm_playback_avail(runtime) >= runtime->control->avail_min;
}

/**
 * snd_pcm_capture_ready - check whether the capture buffer is available
 * @substream: the pcm substream instance
 *
 * Checks whether enough capture data is available on the capture buffer.
 *
 * Return: Non-zero if available, or zero if not.
 */
static inline int snd_pcm_capture_ready(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        return snd_pcm_capture_avail(runtime) >= runtime->control->avail_min;
}

/**
 * snd_pcm_playback_data - check whether any data exists on the playback buffer
 * @substream: the pcm substream instance
 *
 * Checks whether any data exists on the playback buffer.
 *
 * Return: Non-zero if any data exists, or zero if not. If stop_threshold
 * is bigger or equal to boundary, then this function returns always non-zero.
 */
static inline int snd_pcm_playback_data(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        
        if (runtime->stop_threshold >= runtime->boundary)
                return 1;
        return snd_pcm_playback_avail(runtime) < runtime->buffer_size;
}

/**
 * snd_pcm_playback_empty - check whether the playback buffer is empty
 * @substream: the pcm substream instance
 *
 * Checks whether the playback buffer is empty.
 *
 * Return: Non-zero if empty, or zero if not.
 */
static inline int snd_pcm_playback_empty(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        return snd_pcm_playback_avail(runtime) >= runtime->buffer_size;
}

/**
 * snd_pcm_capture_empty - check whether the capture buffer is empty
 * @substream: the pcm substream instance
 *
 * Checks whether the capture buffer is empty.
 *
 * Return: Non-zero if empty, or zero if not.
 */
static inline int snd_pcm_capture_empty(struct snd_pcm_substream *substream)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        return snd_pcm_capture_avail(runtime) == 0;
}

/**
 * snd_pcm_trigger_done - Mark the master substream
 * @substream: the pcm substream instance
 * @master: the linked master substream
 *
 * When multiple substreams of the same card are linked and the hardware
 * supports the single-shot operation, the driver calls this in the loop
 * in snd_pcm_group_for_each_entry() for marking the substream as "done".
 * Then most of trigger operations are performed only to the given master
 * substream.
 *
 * The trigger_master mark is cleared at timestamp updates at the end
 * of trigger operations.
 */
static inline void snd_pcm_trigger_done(struct snd_pcm_substream *substream, 
                                        struct snd_pcm_substream *master)
{
        substream->runtime->trigger_master = master;
}

static inline int hw_is_mask(int var)
{
        return var >= SNDRV_PCM_HW_PARAM_FIRST_MASK &&
                var <= SNDRV_PCM_HW_PARAM_LAST_MASK;
}

static inline int hw_is_interval(int var)
{
        return var >= SNDRV_PCM_HW_PARAM_FIRST_INTERVAL &&
                var <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL;
}

static inline struct snd_mask *hw_param_mask(struct snd_pcm_hw_params *params,
                                     snd_pcm_hw_param_t var)
{
        return &params->masks[var - SNDRV_PCM_HW_PARAM_FIRST_MASK];
}

static inline struct snd_interval *hw_param_interval(struct snd_pcm_hw_params *params,
                                             snd_pcm_hw_param_t var)
{
        return &params->intervals[var - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL];
}

static inline const struct snd_mask *hw_param_mask_c(const struct snd_pcm_hw_params *params,
                                             snd_pcm_hw_param_t var)
{
        return &params->masks[var - SNDRV_PCM_HW_PARAM_FIRST_MASK];
}

static inline const struct snd_interval *hw_param_interval_c(const struct snd_pcm_hw_params *params,
                                                     snd_pcm_hw_param_t var)
{
        return &params->intervals[var - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL];
}

/**
 * params_channels - Get the number of channels from the hw params
 * @p: hw params
 *
 * Return: the number of channels
 */
static inline unsigned int params_channels(const struct snd_pcm_hw_params *p)
{
        return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_CHANNELS)->min;
}

/**
 * params_rate - Get the sample rate from the hw params
 * @p: hw params
 *
 * Return: the sample rate
 */
static inline unsigned int params_rate(const struct snd_pcm_hw_params *p)
{
        return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_RATE)->min;
}

/**
 * params_period_size - Get the period size (in frames) from the hw params
 * @p: hw params
 *
 * Return: the period size in frames
 */
static inline unsigned int params_period_size(const struct snd_pcm_hw_params *p)
{
        return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_PERIOD_SIZE)->min;
}

/**
 * params_periods - Get the number of periods from the hw params
 * @p: hw params
 *
 * Return: the number of periods
 */
static inline unsigned int params_periods(const struct snd_pcm_hw_params *p)
{
        return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_PERIODS)->min;
}

/**
 * params_buffer_size - Get the buffer size (in frames) from the hw params
 * @p: hw params
 *
 * Return: the buffer size in frames
 */
static inline unsigned int params_buffer_size(const struct snd_pcm_hw_params *p)
{
        return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_BUFFER_SIZE)->min;
}

/**
 * params_buffer_bytes - Get the buffer size (in bytes) from the hw params
 * @p: hw params
 *
 * Return: the buffer size in bytes
 */
static inline unsigned int params_buffer_bytes(const struct snd_pcm_hw_params *p)
{
        return hw_param_interval_c(p, SNDRV_PCM_HW_PARAM_BUFFER_BYTES)->min;
}

int snd_interval_refine(struct snd_interval *i, const struct snd_interval *v);
int snd_interval_list(struct snd_interval *i, unsigned int count,
                      const unsigned int *list, unsigned int mask);
int snd_interval_ranges(struct snd_interval *i, unsigned int count,
                        const struct snd_interval *list, unsigned int mask);
int snd_interval_ratnum(struct snd_interval *i,
                        unsigned int rats_count, const struct snd_ratnum *rats,
                        unsigned int *nump, unsigned int *denp);

void _snd_pcm_hw_params_any(struct snd_pcm_hw_params *params);
void _snd_pcm_hw_param_setempty(struct snd_pcm_hw_params *params, snd_pcm_hw_param_t var);

int snd_pcm_hw_refine(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params);

int snd_pcm_hw_constraint_mask64(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
                                 u_int64_t mask);
int snd_pcm_hw_constraint_minmax(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
                                 unsigned int min, unsigned int max);
int snd_pcm_hw_constraint_integer(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var);
int snd_pcm_hw_constraint_list(struct snd_pcm_runtime *runtime, 
                               unsigned int cond,
                               snd_pcm_hw_param_t var,
                               const struct snd_pcm_hw_constraint_list *l);
int snd_pcm_hw_constraint_ranges(struct snd_pcm_runtime *runtime,
                                 unsigned int cond,
                                 snd_pcm_hw_param_t var,
                                 const struct snd_pcm_hw_constraint_ranges *r);
int snd_pcm_hw_constraint_ratnums(struct snd_pcm_runtime *runtime, 
                                  unsigned int cond,
                                  snd_pcm_hw_param_t var,
                                  const struct snd_pcm_hw_constraint_ratnums *r);
int snd_pcm_hw_constraint_ratdens(struct snd_pcm_runtime *runtime, 
                                  unsigned int cond,
                                  snd_pcm_hw_param_t var,
                                  const struct snd_pcm_hw_constraint_ratdens *r);
int snd_pcm_hw_constraint_msbits(struct snd_pcm_runtime *runtime, 
                                 unsigned int cond,
                                 unsigned int width,
                                 unsigned int msbits);
int snd_pcm_hw_constraint_step(struct snd_pcm_runtime *runtime,
                               unsigned int cond,
                               snd_pcm_hw_param_t var,
                               unsigned long step);
int snd_pcm_hw_constraint_pow2(struct snd_pcm_runtime *runtime,
                               unsigned int cond,
                               snd_pcm_hw_param_t var);
int snd_pcm_hw_rule_noresample(struct snd_pcm_runtime *runtime,
                               unsigned int base_rate);
int snd_pcm_hw_rule_add(struct snd_pcm_runtime *runtime,
                        unsigned int cond,
                        int var,
                        snd_pcm_hw_rule_func_t func, void *private,
                        int dep, ...);

/**
 * snd_pcm_hw_constraint_single() - Constrain parameter to a single value
 * @runtime: PCM runtime instance
 * @var: The hw_params variable to constrain
 * @val: The value to constrain to
 *
 * Return: Positive if the value is changed, zero if it's not changed, or a
 * negative error code.
 */
static inline int snd_pcm_hw_constraint_single(
        struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
        unsigned int val)
{
        return snd_pcm_hw_constraint_minmax(runtime, var, val, val);
}

int snd_pcm_format_signed(snd_pcm_format_t format);
int snd_pcm_format_unsigned(snd_pcm_format_t format);
int snd_pcm_format_linear(snd_pcm_format_t format);
int snd_pcm_format_little_endian(snd_pcm_format_t format);
int snd_pcm_format_big_endian(snd_pcm_format_t format);
#if 0 /* just for kernel-doc */
/**
 * snd_pcm_format_cpu_endian - Check the PCM format is CPU-endian
 * @format: the format to check
 *
 * Return: 1 if the given PCM format is CPU-endian, 0 if
 * opposite, or a negative error code if endian not specified.
 */
int snd_pcm_format_cpu_endian(snd_pcm_format_t format);
#endif /* DocBook */
#ifdef SNDRV_LITTLE_ENDIAN
#define snd_pcm_format_cpu_endian(format) snd_pcm_format_little_endian(format)
#else
#define snd_pcm_format_cpu_endian(format) snd_pcm_format_big_endian(format)
#endif
int snd_pcm_format_width(snd_pcm_format_t format);                      /* in bits */
int snd_pcm_format_physical_width(snd_pcm_format_t format);             /* in bits */
ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples);
const unsigned char *snd_pcm_format_silence_64(snd_pcm_format_t format);
int snd_pcm_format_set_silence(snd_pcm_format_t format, void *buf, unsigned int frames);

void snd_pcm_set_ops(struct snd_pcm * pcm, int direction,
                     const struct snd_pcm_ops *ops);
void snd_pcm_set_sync_per_card(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params,
                               const unsigned char *id, unsigned int len);
/**
 * snd_pcm_set_sync - set the PCM sync id
 * @substream: the pcm substream
 *
 * Use the default PCM sync identifier for the specific card.
 */
static inline void snd_pcm_set_sync(struct snd_pcm_substream *substream)
{
        substream->runtime->std_sync_id = true;
}
int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
                      unsigned int cmd, void *arg);                      
void snd_pcm_period_elapsed_under_stream_lock(struct snd_pcm_substream *substream);
void snd_pcm_period_elapsed(struct snd_pcm_substream *substream);
snd_pcm_sframes_t __snd_pcm_lib_xfer(struct snd_pcm_substream *substream,
                                     void *buf, bool interleaved,
                                     snd_pcm_uframes_t frames, bool in_kernel);

static inline snd_pcm_sframes_t
snd_pcm_lib_write(struct snd_pcm_substream *substream,
                  const void __user *buf, snd_pcm_uframes_t frames)
{
        return __snd_pcm_lib_xfer(substream, (void __force *)buf, true, frames, false);
}

static inline snd_pcm_sframes_t
snd_pcm_lib_read(struct snd_pcm_substream *substream,
                 void __user *buf, snd_pcm_uframes_t frames)
{
        return __snd_pcm_lib_xfer(substream, (void __force *)buf, true, frames, false);
}

static inline snd_pcm_sframes_t
snd_pcm_lib_writev(struct snd_pcm_substream *substream,
                   void __user **bufs, snd_pcm_uframes_t frames)
{
        return __snd_pcm_lib_xfer(substream, (void *)bufs, false, frames, false);
}

static inline snd_pcm_sframes_t
snd_pcm_lib_readv(struct snd_pcm_substream *substream,
                  void __user **bufs, snd_pcm_uframes_t frames)
{
        return __snd_pcm_lib_xfer(substream, (void *)bufs, false, frames, false);
}

static inline snd_pcm_sframes_t
snd_pcm_kernel_write(struct snd_pcm_substream *substream,
                     const void *buf, snd_pcm_uframes_t frames)
{
        return __snd_pcm_lib_xfer(substream, (void *)buf, true, frames, true);
}

static inline snd_pcm_sframes_t
snd_pcm_kernel_read(struct snd_pcm_substream *substream,
                    void *buf, snd_pcm_uframes_t frames)
{
        return __snd_pcm_lib_xfer(substream, buf, true, frames, true);
}

static inline snd_pcm_sframes_t
snd_pcm_kernel_writev(struct snd_pcm_substream *substream,
                      void **bufs, snd_pcm_uframes_t frames)
{
        return __snd_pcm_lib_xfer(substream, bufs, false, frames, true);
}

static inline snd_pcm_sframes_t
snd_pcm_kernel_readv(struct snd_pcm_substream *substream,
                     void **bufs, snd_pcm_uframes_t frames)
{
        return __snd_pcm_lib_xfer(substream, bufs, false, frames, true);
}

int snd_pcm_hw_limit_rates(struct snd_pcm_hardware *hw);

static inline int
snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime)
{
        return snd_pcm_hw_limit_rates(&runtime->hw);
}

unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate);
unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit);
unsigned int snd_pcm_rate_mask_intersect(unsigned int rates_a,
                                         unsigned int rates_b);

/**
 * snd_pcm_set_runtime_buffer - Set the PCM runtime buffer
 * @substream: PCM substream to set
 * @bufp: the buffer information, NULL to clear
 *
 * Copy the buffer information to runtime->dma_buffer when @bufp is non-NULL.
 * Otherwise it clears the current buffer information.
 */
static inline void snd_pcm_set_runtime_buffer(struct snd_pcm_substream *substream,
                                              struct snd_dma_buffer *bufp)
{
        struct snd_pcm_runtime *runtime = substream->runtime;
        if (bufp) {
                runtime->dma_buffer_p = bufp;
                runtime->dma_area = bufp->area;
                runtime->dma_addr = bufp->addr;
                runtime->dma_bytes = bufp->bytes;
        } else {
                runtime->dma_buffer_p = NULL;
                runtime->dma_area = NULL;
                runtime->dma_addr = 0;
                runtime->dma_bytes = 0;
        }
}

/**
 * snd_pcm_gettime - Fill the timespec64 depending on the timestamp mode
 * @runtime: PCM runtime instance
 * @tv: timespec64 to fill
 */
static inline void snd_pcm_gettime(struct snd_pcm_runtime *runtime,
                                   struct timespec64 *tv)
{
        switch (runtime->tstamp_type) {
        case SNDRV_PCM_TSTAMP_TYPE_MONOTONIC:
                ktime_get_ts64(tv);
                break;
        case SNDRV_PCM_TSTAMP_TYPE_MONOTONIC_RAW:
                ktime_get_raw_ts64(tv);
                break;
        default:
                ktime_get_real_ts64(tv);
                break;
        }
}

/*
 *  Memory
 */

void snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream);
void snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm);
void snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
                                  int type, struct device *data,
                                  size_t size, size_t max);
void snd_pcm_lib_preallocate_pages_for_all(struct snd_pcm *pcm,
                                          int type, void *data,
                                          size_t size, size_t max);
int snd_pcm_lib_malloc_pages(struct snd_pcm_substream *substream, size_t size);
int snd_pcm_lib_free_pages(struct snd_pcm_substream *substream);

int snd_pcm_set_managed_buffer(struct snd_pcm_substream *substream, int type,
                               struct device *data, size_t size, size_t max);
int snd_pcm_set_managed_buffer_all(struct snd_pcm *pcm, int type,
                                   struct device *data,
                                   size_t size, size_t max);

/**
 * snd_pcm_set_fixed_buffer - Preallocate and set up the fixed size PCM buffer
 * @substream: the pcm substream instance
 * @type: DMA type (SNDRV_DMA_TYPE_*)
 * @data: DMA type dependent data
 * @size: the requested pre-allocation size in bytes
 *
 * This is a variant of snd_pcm_set_managed_buffer(), but this pre-allocates
 * only the given sized buffer and doesn't allow re-allocation nor dynamic
 * allocation of a larger buffer unlike the standard one.
 * The function may return -ENOMEM error, hence the caller must check it.
 *
 * Return: zero if successful, or a negative error code
 */
static inline int __must_check
snd_pcm_set_fixed_buffer(struct snd_pcm_substream *substream, int type,
                                 struct device *data, size_t size)
{
        return snd_pcm_set_managed_buffer(substream, type, data, size, 0);
}

/**
 * snd_pcm_set_fixed_buffer_all - Preallocate and set up the fixed size PCM buffer
 * @pcm: the pcm instance
 * @type: DMA type (SNDRV_DMA_TYPE_*)
 * @data: DMA type dependent data
 * @size: the requested pre-allocation size in bytes
 *
 * Apply the set up of the fixed buffer via snd_pcm_set_fixed_buffer() for
 * all substream.  If any of allocation fails, it returns -ENOMEM, hence the
 * caller must check the return value.
 *
 * Return: zero if successful, or a negative error code
 */
static inline int __must_check
snd_pcm_set_fixed_buffer_all(struct snd_pcm *pcm, int type,
                             struct device *data, size_t size)
{
        return snd_pcm_set_managed_buffer_all(pcm, type, data, size, 0);
}

#define snd_pcm_get_dma_buf(substream) ((substream)->runtime->dma_buffer_p)

/**
 * snd_pcm_sgbuf_get_addr - Get the DMA address at the corresponding offset
 * @substream: PCM substream
 * @ofs: byte offset
 *
 * Return: DMA address
 */
static inline dma_addr_t
snd_pcm_sgbuf_get_addr(struct snd_pcm_substream *substream, unsigned int ofs)
{
        return snd_sgbuf_get_addr(snd_pcm_get_dma_buf(substream), ofs);
}

/**
 * snd_pcm_sgbuf_get_chunk_size - Compute the max size that fits within the
 * contig. page from the given size
 * @substream: PCM substream
 * @ofs: byte offset
 * @size: byte size to examine
 *
 * Return: chunk size
 */
static inline unsigned int
snd_pcm_sgbuf_get_chunk_size(struct snd_pcm_substream *substream,
                             unsigned int ofs, unsigned int size)
{
        return snd_sgbuf_get_chunk_size(snd_pcm_get_dma_buf(substream), ofs, size);
}

int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream,
                             struct vm_area_struct *area);
/* mmap for io-memory area */
#if defined(CONFIG_X86) || defined(CONFIG_PPC) || defined(CONFIG_ALPHA)
#define SNDRV_PCM_INFO_MMAP_IOMEM       SNDRV_PCM_INFO_MMAP
int snd_pcm_lib_mmap_iomem(struct snd_pcm_substream *substream, struct vm_area_struct *area);
#else
#define SNDRV_PCM_INFO_MMAP_IOMEM       0
#define snd_pcm_lib_mmap_iomem  NULL
#endif

int snd_pcm_runtime_buffer_set_silence(struct snd_pcm_runtime *runtime);

/**
 * snd_pcm_limit_isa_dma_size - Get the max size fitting with ISA DMA transfer
 * @dma: DMA number
 * @max: pointer to store the max size
 */
static inline void snd_pcm_limit_isa_dma_size(int dma, size_t *max)
{
        *max = dma < 4 ? 64 * 1024 : 128 * 1024;
}

/*
 *  Misc
 */

#define SNDRV_PCM_DEFAULT_CON_SPDIF     (IEC958_AES0_CON_EMPHASIS_NONE|\
                                         (IEC958_AES1_CON_ORIGINAL<<8)|\
                                         (IEC958_AES1_CON_PCM_CODER<<8)|\
                                         (IEC958_AES3_CON_FS_48000<<24))

const char *snd_pcm_format_name(snd_pcm_format_t format);

/**
 * snd_pcm_direction_name - Get a string naming the direction of a stream
 * @direction: Stream's direction, one of SNDRV_PCM_STREAM_XXX
 *
 * Returns a string naming the direction of the stream.
 */
static inline const char *snd_pcm_direction_name(int direction)
{
        if (direction == SNDRV_PCM_STREAM_PLAYBACK)
                return "Playback";
        else
                return "Capture";
}

/**
 * snd_pcm_stream_str - Get a string naming the direction of a stream
 * @substream: the pcm substream instance
 *
 * Return: A string naming the direction of the stream.
 */
static inline const char *snd_pcm_stream_str(struct snd_pcm_substream *substream)
{
        return snd_pcm_direction_name(substream->stream);
}

/*
 * PCM channel-mapping control API
 */
/* array element of channel maps */
struct snd_pcm_chmap_elem {
        unsigned char channels;
        unsigned char map[15];
};

/* channel map information; retrieved via snd_kcontrol_chip() */
struct snd_pcm_chmap {
        struct snd_pcm *pcm;    /* assigned PCM instance */
        int stream;             /* PLAYBACK or CAPTURE */
        struct snd_kcontrol *kctl;
        const struct snd_pcm_chmap_elem *chmap;
        unsigned int max_channels;
        unsigned int channel_mask;      /* optional: active channels bitmask */
        void *private_data;     /* optional: private data pointer */
};

/**
 * snd_pcm_chmap_substream - get the PCM substream assigned to the given chmap info
 * @info: chmap information
 * @idx: the substream number index
 *
 * Return: the matched PCM substream, or NULL if not found
 */
static inline struct snd_pcm_substream *
snd_pcm_chmap_substream(struct snd_pcm_chmap *info, unsigned int idx)
{
        struct snd_pcm_substream *s;
        for (s = info->pcm->streams[info->stream].substream; s; s = s->next)
                if (s->number == idx)
                        return s;
        return NULL;
}

/* ALSA-standard channel maps (RL/RR prior to C/LFE) */
extern const struct snd_pcm_chmap_elem snd_pcm_std_chmaps[];
/* Other world's standard channel maps (C/LFE prior to RL/RR) */
extern const struct snd_pcm_chmap_elem snd_pcm_alt_chmaps[];

/* bit masks to be passed to snd_pcm_chmap.channel_mask field */
#define SND_PCM_CHMAP_MASK_24   ((1U << 2) | (1U << 4))
#define SND_PCM_CHMAP_MASK_246  (SND_PCM_CHMAP_MASK_24 | (1U << 6))
#define SND_PCM_CHMAP_MASK_2468 (SND_PCM_CHMAP_MASK_246 | (1U << 8))

int snd_pcm_add_chmap_ctls(struct snd_pcm *pcm, int stream,
                           const struct snd_pcm_chmap_elem *chmap,
                           int max_channels,
                           unsigned long private_value,
                           struct snd_pcm_chmap **info_ret);

/**
 * pcm_format_to_bits - Strong-typed conversion of pcm_format to bitwise
 * @pcm_format: PCM format
 *
 * Return: 64bit mask corresponding to the given PCM format
 */
static inline u64 pcm_format_to_bits(snd_pcm_format_t pcm_format)
{
        return 1ULL << (__force int) pcm_format;
}

/**
 * pcm_for_each_format - helper to iterate for each format type
 * @f: the iterator variable in snd_pcm_format_t type
 */
#define pcm_for_each_format(f)                                          \
        for ((f) = SNDRV_PCM_FORMAT_FIRST;                              \
             (__force int)(f) <= (__force int)SNDRV_PCM_FORMAT_LAST;    \
             (f) = (__force snd_pcm_format_t)((__force int)(f) + 1))

/* printk helpers */
#define pcm_err(pcm, fmt, args...) \
        dev_err((pcm)->card->dev, fmt, ##args)
#define pcm_warn(pcm, fmt, args...) \
        dev_warn((pcm)->card->dev, fmt, ##args)
#define pcm_dbg(pcm, fmt, args...) \
        dev_dbg((pcm)->card->dev, fmt, ##args)

/* helpers for copying between iov_iter and iomem */
size_t copy_to_iter_fromio(const void __iomem *src, size_t bytes,
                           struct iov_iter *iter) __must_check;
size_t copy_from_iter_toio(void __iomem *dst, size_t bytes,
                           struct iov_iter *iter) __must_check;

struct snd_pcm_status64 {
        snd_pcm_state_t state;          /* stream state */
        u8 rsvd[4];
        s64 trigger_tstamp_sec;         /* time when stream was started/stopped/paused */
        s64 trigger_tstamp_nsec;
        s64 tstamp_sec;                 /* reference timestamp */
        s64 tstamp_nsec;
        snd_pcm_uframes_t appl_ptr;     /* appl ptr */
        snd_pcm_uframes_t hw_ptr;       /* hw ptr */
        snd_pcm_sframes_t delay;        /* current delay in frames */
        snd_pcm_uframes_t avail;        /* number of frames available */
        snd_pcm_uframes_t avail_max;    /* max frames available on hw since last status */
        snd_pcm_uframes_t overrange;    /* count of ADC (capture) overrange detections from last status */
        snd_pcm_state_t suspended_state; /* suspended stream state */
        __u32 audio_tstamp_data;         /* needed for 64-bit alignment, used for configs/report to/from userspace */
        s64 audio_tstamp_sec;           /* sample counter, wall clock, PHC or on-demand sync'ed */
        s64 audio_tstamp_nsec;
        s64 driver_tstamp_sec;          /* useful in case reference system tstamp is reported with delay */
        s64 driver_tstamp_nsec;
        __u32 audio_tstamp_accuracy;    /* in ns units, only valid if indicated in audio_tstamp_data */
        unsigned char reserved[52-4*sizeof(s64)]; /* must be filled with zero */
};

#define SNDRV_PCM_IOCTL_STATUS64        _IOR('A', 0x20, struct snd_pcm_status64)
#define SNDRV_PCM_IOCTL_STATUS_EXT64    _IOWR('A', 0x24, struct snd_pcm_status64)

struct snd_pcm_status32 {
        snd_pcm_state_t state;          /* stream state */
        s32 trigger_tstamp_sec; /* time when stream was started/stopped/paused */
        s32 trigger_tstamp_nsec;
        s32 tstamp_sec;         /* reference timestamp */
        s32 tstamp_nsec;
        u32 appl_ptr;           /* appl ptr */
        u32 hw_ptr;             /* hw ptr */
        s32 delay;              /* current delay in frames */
        u32 avail;              /* number of frames available */
        u32 avail_max;          /* max frames available on hw since last status */
        u32 overrange;          /* count of ADC (capture) overrange detections from last status */
        snd_pcm_state_t suspended_state;        /* suspended stream state */
        u32 audio_tstamp_data;  /* needed for 64-bit alignment, used for configs/report to/from userspace */
        s32 audio_tstamp_sec;   /* sample counter, wall clock, PHC or on-demand sync'ed */
        s32 audio_tstamp_nsec;
        s32 driver_tstamp_sec;  /* useful in case reference system tstamp is reported with delay */
        s32 driver_tstamp_nsec;
        u32 audio_tstamp_accuracy;      /* in ns units, only valid if indicated in audio_tstamp_data */
        unsigned char reserved[52-4*sizeof(s32)]; /* must be filled with zero */
};

#define SNDRV_PCM_IOCTL_STATUS32        _IOR('A', 0x20, struct snd_pcm_status32)
#define SNDRV_PCM_IOCTL_STATUS_EXT32    _IOWR('A', 0x24, struct snd_pcm_status32)

#endif /* __SOUND_PCM_H */