pcm.h

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#ifndef __SOUND_PCM_H
#define __SOUND_PCM_H

/*
 *  Digital Audio (PCM) abstract layer
 *  Copyright (c) by Jaroslav Kysela <[email protected]>
 *                   Abramo Bagnara <[email protected]>
 *
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 2 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#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>

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

#if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
#include <sound/pcm_oss.h>
#endif

/*
 *  Hardware (lowlevel) section
 */

struct snd_pcm_hardware {
    unsigned int info;      /* SNDRV_PCM_INFO_* */
    u64 formats;            /* SNDRV_PCM_FMTBIT_* */
    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_substream;

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);
    snd_pcm_uframes_t (*pointer)(struct snd_pcm_substream *substream);
    int (*copy)(struct snd_pcm_substream *substream, int channel,
            snd_pcm_uframes_t pos,
            void __user *buf, snd_pcm_uframes_t count);
    int (*silence)(struct snd_pcm_substream *substream, int channel, 
               snd_pcm_uframes_t pos, snd_pcm_uframes_t count);
    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_FALSE      ((void *)0)
#define SNDRV_PCM_IOCTL1_TRUE       ((void *)1)

#define SNDRV_PCM_IOCTL1_RESET      0
#define SNDRV_PCM_IOCTL1_INFO       1
#define SNDRV_PCM_IOCTL1_CHANNEL_INFO   2
#define SNDRV_PCM_IOCTL1_GSTATE     3
#define SNDRV_PCM_IOCTL1_FIFO_SIZE  4

#define SNDRV_PCM_TRIGGER_STOP      0
#define SNDRV_PCM_TRIGGER_START     1
#define SNDRV_PCM_TRIGGER_PAUSE_PUSH    3
#define SNDRV_PCM_TRIGGER_PAUSE_RELEASE 4
#define SNDRV_PCM_TRIGGER_SUSPEND   5
#define SNDRV_PCM_TRIGGER_RESUME    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     (1<<0)      /* 5512Hz */
#define SNDRV_PCM_RATE_8000     (1<<1)      /* 8000Hz */
#define SNDRV_PCM_RATE_11025        (1<<2)      /* 11025Hz */
#define SNDRV_PCM_RATE_16000        (1<<3)      /* 16000Hz */
#define SNDRV_PCM_RATE_22050        (1<<4)      /* 22050Hz */
#define SNDRV_PCM_RATE_32000        (1<<5)      /* 32000Hz */
#define SNDRV_PCM_RATE_44100        (1<<6)      /* 44100Hz */
#define SNDRV_PCM_RATE_48000        (1<<7)      /* 48000Hz */
#define SNDRV_PCM_RATE_64000        (1<<8)      /* 64000Hz */
#define SNDRV_PCM_RATE_88200        (1<<9)      /* 88200Hz */
#define SNDRV_PCM_RATE_96000        (1<<10)     /* 96000Hz */
#define SNDRV_PCM_RATE_176400       (1<<11)     /* 176400Hz */
#define SNDRV_PCM_RATE_192000       (1<<12)     /* 192000Hz */

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

#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
#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
#endif

struct snd_pcm_file {
    struct snd_pcm_substream *substream;
    int no_compat_mmap;
};

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;
    snd_pcm_hw_rule_func_t func;
    int var;
    int deps[4];
    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;
    struct snd_ratnum *rats;
};

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

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

struct snd_pcm_hwptr_log;

struct snd_pcm_runtime {
    /* -- Status -- */
    struct snd_pcm_substream *trigger_master;
    struct timespec trigger_tstamp; /* trigger timestamp */
    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 */

    /* -- 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 -- */
    int tstamp_mode;        /* mmap timestamp is updated */
    unsigned int period_step;
    snd_pcm_uframes_t start_threshold;
    snd_pcm_uframes_t stop_threshold;
    snd_pcm_uframes_t silence_threshold; /* Silence filling happens when
                        noise is nearest than this */
    snd_pcm_uframes_t silence_size; /* Silence filling size */
    snd_pcm_uframes_t boundary; /* pointers wrap point */

    snd_pcm_uframes_t silence_start; /* starting pointer to silence area */
    snd_pcm_uframes_t silence_filled; /* size filled with silence */

    union snd_pcm_sync_id sync; /* hardware synchronization 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 fasync_struct *fasync;

    /* -- 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;

    /* -- interrupt callbacks -- */
    void (*transfer_ack_begin)(struct snd_pcm_substream *substream);
    void (*transfer_ack_end)(struct snd_pcm_substream *substream);

    /* -- 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 */

#if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
    /* -- OSS things -- */
    struct snd_pcm_oss_runtime oss;
#endif

#ifdef CONFIG_SND_PCM_XRUN_DEBUG
    struct snd_pcm_hwptr_log *hwptr_log;
#endif
};

struct snd_pcm_group {      /* keep linked substreams */
    spinlock_t lock;
    struct list_head substreams;
    int count;
};

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;
    unsigned int dma_buf_id;
    size_t dma_max;
    /* -- hardware operations -- */
    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 */
    /* -- 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 -- */
    void *file;
    int ref_count;
    atomic_t mmap_count;
    unsigned int f_flags;
    void (*pcm_release)(struct snd_pcm_substream *);
    struct pid *pid;
#if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
    /* -- OSS things -- */
    struct snd_pcm_oss_substream oss;
#endif
#ifdef CONFIG_SND_VERBOSE_PROCFS
    struct snd_info_entry *proc_root;
    struct snd_info_entry *proc_info_entry;
    struct snd_info_entry *proc_hw_params_entry;
    struct snd_info_entry *proc_sw_params_entry;
    struct snd_info_entry *proc_status_entry;
    struct snd_info_entry *proc_prealloc_entry;
    struct snd_info_entry *proc_prealloc_max_entry;
#endif
    /* misc flags */
    unsigned int hw_opened: 1;
};

#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 defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
    /* -- OSS things -- */
    struct snd_pcm_oss_stream oss;
#endif
#ifdef CONFIG_SND_VERBOSE_PROCFS
    struct snd_info_entry *proc_root;
    struct snd_info_entry *proc_info_entry;
#ifdef CONFIG_SND_PCM_XRUN_DEBUG
    unsigned int xrun_debug;    /* 0 = disabled, 1 = verbose, 2 = stacktrace */
    struct snd_info_entry *proc_xrun_debug_entry;
#endif
#endif
    struct snd_kcontrol *chmap_kctl; /* channel-mapping controls */
};

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);
    struct device *dev; /* actual hw device this belongs to */
    bool internal; /* pcm is for internal use only */
#if defined(CONFIG_SND_PCM_OSS) || defined(CONFIG_SND_PCM_OSS_MODULE)
    struct snd_pcm_oss oss;
#endif
};

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;
};

/*
 *  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);

int snd_pcm_notify(struct snd_pcm_notify *notify, int nfree);

/*
 *  Native I/O
 */

extern rwlock_t snd_pcm_link_rwlock;

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_status(struct snd_pcm_substream *substream,
           struct snd_pcm_status *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);
#ifdef CONFIG_PM
int snd_pcm_suspend(struct snd_pcm_substream *substream);
int snd_pcm_suspend_all(struct snd_pcm *pcm);
#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);
void snd_pcm_vma_notify_data(void *client, void *data);
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
 */

static inline int snd_pcm_stream_linked(struct snd_pcm_substream *substream)
{
    return substream->group != &substream->self_group;
}

static inline void snd_pcm_stream_lock(struct snd_pcm_substream *substream)
{
    read_lock(&snd_pcm_link_rwlock);
    spin_lock(&substream->self_group.lock);
}

static inline void snd_pcm_stream_unlock(struct snd_pcm_substream *substream)
{
    spin_unlock(&substream->self_group.lock);
    read_unlock(&snd_pcm_link_rwlock);
}

static inline void snd_pcm_stream_lock_irq(struct snd_pcm_substream *substream)
{
    read_lock_irq(&snd_pcm_link_rwlock);
    spin_lock(&substream->self_group.lock);
}

static inline void snd_pcm_stream_unlock_irq(struct snd_pcm_substream *substream)
{
    spin_unlock(&substream->self_group.lock);
    read_unlock_irq(&snd_pcm_link_rwlock);
}

#define snd_pcm_stream_lock_irqsave(substream, flags) \
do { \
    read_lock_irqsave(&snd_pcm_link_rwlock, (flags)); \
    spin_lock(&substream->self_group.lock); \
} while (0)

#define snd_pcm_stream_unlock_irqrestore(substream, flags) \
do { \
    spin_unlock(&substream->self_group.lock); \
    read_unlock_irqrestore(&snd_pcm_link_rwlock, (flags)); \
} while (0)

#define snd_pcm_group_for_each_entry(s, substream) \
    list_for_each_entry(s, &substream->group->substreams, link_list)

static inline int snd_pcm_running(struct snd_pcm_substream *substream)
{
    return (substream->runtime->status->state == SNDRV_PCM_STATE_RUNNING ||
        (substream->runtime->status->state == SNDRV_PCM_STATE_DRAINING &&
         substream->stream == SNDRV_PCM_STREAM_PLAYBACK));
}

static inline ssize_t bytes_to_samples(struct snd_pcm_runtime *runtime, ssize_t size)
{
    return size * 8 / runtime->sample_bits;
}

static inline snd_pcm_sframes_t bytes_to_frames(struct snd_pcm_runtime *runtime, ssize_t size)
{
    return size * 8 / runtime->frame_bits;
}

static inline ssize_t samples_to_bytes(struct snd_pcm_runtime *runtime, ssize_t size)
{
    return size * runtime->sample_bits / 8;
}

static inline ssize_t frames_to_bytes(struct snd_pcm_runtime *runtime, snd_pcm_sframes_t size)
{
    return size * runtime->frame_bits / 8;
}

static inline int frame_aligned(struct snd_pcm_runtime *runtime, ssize_t bytes)
{
    return bytes % runtime->byte_align == 0;
}

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);
}

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);
}

/*
 *  result is: 0 ... (boundary - 1)
 */
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;
}

/*
 *  result is: 0 ... (boundary - 1)
 */
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;
}

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);
}

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);
}

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;
}

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;
}

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;
}

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;
}

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;
}

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];
}

#define params_channels(p) \
    (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_CHANNELS)->min)
#define params_rate(p) \
    (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_RATE)->min)
#define params_period_size(p) \
    (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_PERIOD_SIZE)->min)
#define params_periods(p) \
    (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_PERIODS)->min)
#define params_buffer_size(p) \
    (hw_param_interval_c((p), SNDRV_PCM_HW_PARAM_BUFFER_SIZE)->min)
#define params_buffer_bytes(p) \
    (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);
void snd_interval_mul(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c);
void snd_interval_div(const struct snd_interval *a, const struct snd_interval *b, struct snd_interval *c);
void snd_interval_muldivk(const struct snd_interval *a, const struct snd_interval *b, 
              unsigned int k, struct snd_interval *c);
void snd_interval_mulkdiv(const struct snd_interval *a, unsigned int k,
              const struct snd_interval *b, struct snd_interval *c);
int snd_interval_list(struct snd_interval *i, unsigned int count,
              const unsigned int *list, unsigned int mask);
int snd_interval_ratnum(struct snd_interval *i,
            unsigned int rats_count, 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_params_choose(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params);

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

int snd_pcm_hw_constraints_init(struct snd_pcm_substream *substream);
int snd_pcm_hw_constraints_complete(struct snd_pcm_substream *substream);

int snd_pcm_hw_constraint_mask(struct snd_pcm_runtime *runtime, snd_pcm_hw_param_t var,
                   u_int32_t mask);
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_ratnums(struct snd_pcm_runtime *runtime, 
                  unsigned int cond,
                  snd_pcm_hw_param_t var,
                  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,
                  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, ...);

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 DocBook */

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);
snd_pcm_format_t snd_pcm_build_linear_format(int width, int unsignd, int big_endian);

void snd_pcm_set_ops(struct snd_pcm * pcm, int direction, struct snd_pcm_ops *ops);
void snd_pcm_set_sync(struct snd_pcm_substream *substream);
int snd_pcm_lib_interleave_len(struct snd_pcm_substream *substream);
int snd_pcm_lib_ioctl(struct snd_pcm_substream *substream,
              unsigned int cmd, void *arg);                      
int snd_pcm_update_state(struct snd_pcm_substream *substream,
             struct snd_pcm_runtime *runtime);
int snd_pcm_update_hw_ptr(struct snd_pcm_substream *substream);
int snd_pcm_playback_xrun_check(struct snd_pcm_substream *substream);
int snd_pcm_capture_xrun_check(struct snd_pcm_substream *substream);
int snd_pcm_playback_xrun_asap(struct snd_pcm_substream *substream);
int snd_pcm_capture_xrun_asap(struct snd_pcm_substream *substream);
void snd_pcm_playback_silence(struct snd_pcm_substream *substream, snd_pcm_uframes_t new_hw_ptr);
void snd_pcm_period_elapsed(struct snd_pcm_substream *substream);
snd_pcm_sframes_t snd_pcm_lib_write(struct snd_pcm_substream *substream,
                    const void __user *buf,
                    snd_pcm_uframes_t frames);
snd_pcm_sframes_t snd_pcm_lib_read(struct snd_pcm_substream *substream,
                   void __user *buf, snd_pcm_uframes_t frames);
snd_pcm_sframes_t snd_pcm_lib_writev(struct snd_pcm_substream *substream,
                     void __user **bufs, snd_pcm_uframes_t frames);
snd_pcm_sframes_t snd_pcm_lib_readv(struct snd_pcm_substream *substream,
                    void __user **bufs, snd_pcm_uframes_t frames);

extern const struct snd_pcm_hw_constraint_list snd_pcm_known_rates;

int snd_pcm_limit_hw_rates(struct snd_pcm_runtime *runtime);
unsigned int snd_pcm_rate_to_rate_bit(unsigned int rate);
unsigned int snd_pcm_rate_bit_to_rate(unsigned int rate_bit);

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;
    }
}

/*
 *  Timer interface
 */

void snd_pcm_timer_resolution_change(struct snd_pcm_substream *substream);
void snd_pcm_timer_init(struct snd_pcm_substream *substream);
void snd_pcm_timer_done(struct snd_pcm_substream *substream);

static inline void snd_pcm_gettime(struct snd_pcm_runtime *runtime,
                   struct timespec *tv)
{
    if (runtime->tstamp_type == SNDRV_PCM_TSTAMP_TYPE_MONOTONIC)
        do_posix_clock_monotonic_gettime(tv);
    else
        getnstimeofday(tv);
}

/*
 *  Memory
 */

int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream);
int snd_pcm_lib_preallocate_free_for_all(struct snd_pcm *pcm);
int snd_pcm_lib_preallocate_pages(struct snd_pcm_substream *substream,
                  int type, struct device *data,
                  size_t size, size_t max);
int 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_lib_alloc_vmalloc_buffer(struct snd_pcm_substream *substream,
                      size_t size, gfp_t gfp_flags);
int snd_pcm_lib_free_vmalloc_buffer(struct snd_pcm_substream *substream);
struct page *snd_pcm_lib_get_vmalloc_page(struct snd_pcm_substream *substream,
                      unsigned long offset);
#if 0 /* for kernel-doc */

static int snd_pcm_lib_alloc_vmalloc_buffer
            (struct snd_pcm_substream *substream, size_t size);
static int snd_pcm_lib_alloc_vmalloc_32_buffer
            (struct snd_pcm_substream *substream, size_t size);
#endif
#define snd_pcm_lib_alloc_vmalloc_buffer(subs, size) \
    _snd_pcm_lib_alloc_vmalloc_buffer \
            (subs, size, GFP_KERNEL | __GFP_HIGHMEM | __GFP_ZERO)
#define snd_pcm_lib_alloc_vmalloc_32_buffer(subs, size) \
    _snd_pcm_lib_alloc_vmalloc_buffer \
            (subs, size, GFP_KERNEL | GFP_DMA32 | __GFP_ZERO)

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

#ifdef CONFIG_SND_DMA_SGBUF
/*
 * SG-buffer handling
 */
#define snd_pcm_substream_sgbuf(substream) \
    snd_pcm_get_dma_buf(substream)->private_data

struct page *snd_pcm_sgbuf_ops_page(struct snd_pcm_substream *substream,
                    unsigned long offset);
#else /* !SND_DMA_SGBUF */
/*
 * fake using a continuous buffer
 */
#define snd_pcm_sgbuf_ops_page  NULL
#endif /* SND_DMA_SGBUF */

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);
}

static inline void *
snd_pcm_sgbuf_get_ptr(struct snd_pcm_substream *substream, unsigned int ofs)
{
    return snd_sgbuf_get_ptr(snd_pcm_get_dma_buf(substream), ofs);
}

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);
}

/* handle mmap counter - PCM mmap callback should handle this counter properly */
static inline void snd_pcm_mmap_data_open(struct vm_area_struct *area)
{
    struct snd_pcm_substream *substream = (struct snd_pcm_substream *)area->vm_private_data;
    atomic_inc(&substream->mmap_count);
}

static inline void snd_pcm_mmap_data_close(struct vm_area_struct *area)
{
    struct snd_pcm_substream *substream = (struct snd_pcm_substream *)area->vm_private_data;
    atomic_dec(&substream->mmap_count);
}

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

#define snd_pcm_lib_mmap_vmalloc NULL

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))

#define PCM_RUNTIME_CHECK(sub) snd_BUG_ON(!(sub) || !(sub)->runtime)

const char *snd_pcm_format_name(snd_pcm_format_t format);

static inline const char *snd_pcm_stream_str(struct snd_pcm_substream *substream)
{
    if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
        return "Playback";
    else
        return "Capture";
}

/*
 * 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 */
};

/* get the PCM substream assigned to the given chmap info */
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);

#endif /* __SOUND_PCM_H */