Commit fa880775 authored by Lars-Peter Clausen's avatar Lars-Peter Clausen Committed by Mark Brown
Browse files

ASoC: Add helper functions bias level management 



Currently drivers are responsible for managing the bias_level field of
their DAPM context. The DAPM state itself is managed by the DAPM core
though and the core has certain expectations on how and when the bias_level
field should be updated. If drivers don't adhere to these undefined
behavior can occur.

This patch adds a few helper functions for manipulating the DAPM context
state, each function with a description on when it should be used and what
its effects are. This will also help us to move more of the bias_level
management from drivers to the DAPM core.

For convenience also add snd_soc_codec_* wrappers around these helpers.

Signed-off-by: default avatarLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: default avatarMark Brown <broonie@kernel.org>
parent 39ed68c8

include/sound/soc-dapm.h

+34 −0
Original line number Diff line number Diff line
@@ -444,6 +444,9 @@ int snd_soc_dapm_dai_get_connected_widgets(struct snd_soc_dai *dai, int stream, 
struct snd_soc_dapm_context *snd_soc_dapm_kcontrol_dapm(

	struct snd_kcontrol *kcontrol);



int snd_soc_dapm_force_bias_level(struct snd_soc_dapm_context *dapm,

	enum snd_soc_bias_level level);



/* dapm widget types */

enum snd_soc_dapm_type {

	snd_soc_dapm_input = 0,		/* input pin */
@@ -623,4 +626,35 @@ struct snd_soc_dapm_stats { 
	int neighbour_checks;

};



/**

 * snd_soc_dapm_init_bias_level() - Initialize DAPM bias level

 * @dapm: The DAPM context to initialize

 * @level: The DAPM level to initialize to

 *

 * This function only sets the driver internal state of the DAPM level and will

 * not modify the state of the device. Hence it should not be used during normal

 * operation, but only to synchronize the internal state to the device state.

 * E.g. during driver probe to set the DAPM level to the one corresponding with

 * the power-on reset state of the device.

 *

 * To change the DAPM state of the device use snd_soc_dapm_set_bias_level().

 */

static inline void snd_soc_dapm_init_bias_level(

	struct snd_soc_dapm_context *dapm, enum snd_soc_bias_level level)

{

	dapm->bias_level = level;

}



/**

 * snd_soc_dapm_get_bias_level() - Get current DAPM bias level

 * @dapm: The context for which to get the bias level

 *

 * Returns: The current bias level of the passed DAPM context.

 */

static inline enum snd_soc_bias_level snd_soc_dapm_get_bias_level(

	struct snd_soc_dapm_context *dapm)

{

	return dapm->bias_level;

}



#endif

include/sound/soc.h

+40 −0
Original line number Diff line number Diff line
@@ -1281,6 +1281,46 @@ static inline struct snd_soc_dapm_context *snd_soc_codec_get_dapm( 
	return &codec->dapm;

}



/**

 * snd_soc_dapm_init_bias_level() - Initialize CODEC DAPM bias level

 * @dapm: The CODEC for which to initialize the DAPM bias level

 * @level: The DAPM level to initialize to

 *

 * Initializes the CODEC DAPM bias level. See snd_soc_dapm_init_bias_level().

 */

static inline void snd_soc_codec_init_bias_level(struct snd_soc_codec *codec,

	enum snd_soc_bias_level level)

{

	snd_soc_dapm_init_bias_level(snd_soc_codec_get_dapm(codec), level);

}



/**

 * snd_soc_dapm_get_bias_level() - Get current CODEC DAPM bias level

 * @codec: The CODEC for which to get the DAPM bias level

 *

 * Returns: The current DAPM bias level of the CODEC.

 */

static inline enum snd_soc_bias_level snd_soc_codec_get_bias_level(

	struct snd_soc_codec *codec)

{

	return snd_soc_dapm_get_bias_level(snd_soc_codec_get_dapm(codec));

}



/**

 * snd_soc_codec_force_bias_level() - Set the CODEC DAPM bias level

 * @codec: The CODEC for which to set the level

 * @level: The level to set to

 *

 * Forces the CODEC bias level to a specific state. See

 * snd_soc_dapm_force_bias_level().

 */

static inline int snd_soc_codec_force_bias_level(struct snd_soc_codec *codec,

	enum snd_soc_bias_level level)

{

	return snd_soc_dapm_force_bias_level(snd_soc_codec_get_dapm(codec),

		level);

}



/**

 * snd_soc_dapm_kcontrol_codec() - Returns the codec associated to a kcontrol

 * @kcontrol: The kcontrol

sound/soc/soc-dapm.c

+31 −4
Original line number Diff line number Diff line
@@ -525,6 +525,35 @@ static void soc_dapm_async_complete(struct snd_soc_dapm_context *dapm) 
		snd_soc_component_async_complete(dapm->component);

}



/**

 * snd_soc_dapm_force_bias_level() - Sets the DAPM bias level

 * @dapm: The DAPM context for which to set the level

 * @level: The level to set

 *

 * Forces the DAPM bias level to a specific state. It will call the bias level

 * callback of DAPM context with the specified level. This will even happen if

 * the context is already at the same level. Furthermore it will not go through

 * the normal bias level sequencing, meaning any intermediate states between the

 * current and the target state will not be entered.

 *

 * Note that the change in bias level is only temporary and the next time

 * snd_soc_dapm_sync() is called the state will be set to the level as

 * determined by the DAPM core. The function is mainly intended to be used to

 * used during probe or resume from suspend to power up the device so

 * initialization can be done, before the DAPM core takes over.

 */

int snd_soc_dapm_force_bias_level(struct snd_soc_dapm_context *dapm,

	enum snd_soc_bias_level level)

{

	int ret = 0;



	if (dapm->set_bias_level)

		ret = dapm->set_bias_level(dapm, level);



	return ret;

}

EXPORT_SYMBOL_GPL(snd_soc_dapm_force_bias_level);



/**

 * snd_soc_dapm_set_bias_level - set the bias level for the system

 * @dapm: DAPM context
@@ -547,10 +576,8 @@ static int snd_soc_dapm_set_bias_level(struct snd_soc_dapm_context *dapm, 
	if (ret != 0)

		goto out;



	if (dapm->set_bias_level)

		ret = dapm->set_bias_level(dapm, level);

	else if (!card || dapm != &card->dapm)

		dapm->bias_level = level;

	if (!card || dapm != &card->dapm)

		ret = snd_soc_dapm_force_bias_level(dapm, level);



	if (ret != 0)

		goto out;

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