soc-dpcm.h

Go to the documentation of this file.

/*
 * linux/sound/soc-dpcm.h -- ALSA SoC Dynamic PCM Support
 *
 * Author:      Liam Girdwood <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef __LINUX_SND_SOC_DPCM_H
#define __LINUX_SND_SOC_DPCM_H

#include <linux/list.h>
#include <sound/pcm.h>

struct snd_soc_pcm_runtime;

/*
 * Types of runtime_update to perform. e.g. originated from FE PCM ops
 * or audio route changes triggered by muxes/mixers.
 */
enum snd_soc_dpcm_update {
    SND_SOC_DPCM_UPDATE_NO  = 0,
    SND_SOC_DPCM_UPDATE_BE,
    SND_SOC_DPCM_UPDATE_FE,
};

/*
 * Dynamic PCM Frontend -> Backend link management states.
 */
enum snd_soc_dpcm_link_state {
    SND_SOC_DPCM_LINK_STATE_NEW = 0,    /* newly created link */
    SND_SOC_DPCM_LINK_STATE_FREE,       /* link to be dismantled */
};

/*
 * Dynamic PCM Frontend -> Backend link PCM states.
 */
enum snd_soc_dpcm_state {
    SND_SOC_DPCM_STATE_NEW  = 0,
    SND_SOC_DPCM_STATE_OPEN,
    SND_SOC_DPCM_STATE_HW_PARAMS,
    SND_SOC_DPCM_STATE_PREPARE,
    SND_SOC_DPCM_STATE_START,
    SND_SOC_DPCM_STATE_STOP,
    SND_SOC_DPCM_STATE_PAUSED,
    SND_SOC_DPCM_STATE_SUSPEND,
    SND_SOC_DPCM_STATE_HW_FREE,
    SND_SOC_DPCM_STATE_CLOSE,
};

/*
 * Dynamic PCM trigger ordering. Triggering flexibility is required as some
 * DSPs require triggering before/after their CPU platform and DAIs.
 *
 * i.e. some clients may want to manually order this call in their PCM
 * trigger() whilst others will just use the regular core ordering.
 */
enum snd_soc_dpcm_trigger {
    SND_SOC_DPCM_TRIGGER_PRE        = 0,
    SND_SOC_DPCM_TRIGGER_POST,
    SND_SOC_DPCM_TRIGGER_BESPOKE,
};

/*
 * Dynamic PCM link
 * This links together a FE and BE DAI at runtime and stores the link
 * state information and the hw_params configuration.
 */
struct snd_soc_dpcm {
    /* FE and BE DAIs*/
    struct snd_soc_pcm_runtime *be;
    struct snd_soc_pcm_runtime *fe;

    /* link state */
    enum snd_soc_dpcm_link_state state;

    /* list of BE and FE for this DPCM link */
    struct list_head list_be;
    struct list_head list_fe;

    /* hw params for this link - may be different for each link */
    struct snd_pcm_hw_params hw_params;
#ifdef CONFIG_DEBUG_FS
    struct dentry *debugfs_state;
#endif
};

/*
 * Dynamic PCM runtime data.
 */
struct snd_soc_dpcm_runtime {
    struct list_head be_clients;
    struct list_head fe_clients;

    int users;
    struct snd_pcm_runtime *runtime;
    struct snd_pcm_hw_params hw_params;

    /* state and update */
    enum snd_soc_dpcm_update runtime_update;
    enum snd_soc_dpcm_state state;
};

/* can this BE stop and free */
int snd_soc_dpcm_can_be_free_stop(struct snd_soc_pcm_runtime *fe,
        struct snd_soc_pcm_runtime *be, int stream);

/* can this BE perform a hw_params() */
int snd_soc_dpcm_can_be_params(struct snd_soc_pcm_runtime *fe,
        struct snd_soc_pcm_runtime *be, int stream);

/* is the current PCM operation for this FE ? */
int snd_soc_dpcm_fe_can_update(struct snd_soc_pcm_runtime *fe, int stream);

/* is the current PCM operation for this BE ? */
int snd_soc_dpcm_be_can_update(struct snd_soc_pcm_runtime *fe,
        struct snd_soc_pcm_runtime *be, int stream);

/* get the substream for this BE */
struct snd_pcm_substream *
    snd_soc_dpcm_get_substream(struct snd_soc_pcm_runtime *be, int stream);

/* get the BE runtime state */
enum snd_soc_dpcm_state
    snd_soc_dpcm_be_get_state(struct snd_soc_pcm_runtime *be, int stream);

/* set the BE runtime state */
void snd_soc_dpcm_be_set_state(struct snd_soc_pcm_runtime *be, int stream,
    enum snd_soc_dpcm_state state);

/* internal use only */
int soc_dpcm_be_digital_mute(struct snd_soc_pcm_runtime *fe, int mute);
int soc_dpcm_debugfs_add(struct snd_soc_pcm_runtime *rtd);
int soc_dpcm_runtime_update(struct snd_soc_dapm_widget *);

#endif