Audio Framework

RTOS-integrated Audio Framework. More...

Data Structures
struct	sf_audio_playback_common_instance_ctrl_t
struct	sf_audio_playback_instance_ctrl_t

Macros
#define	SF_AUDIO_PLAYBACK_CODE_VERSION_MAJOR   (2U)
#define	SF_AUDIO_PLAYBACK_STACK_SIZE   (SF_AUDIO_PLAYBACK_CFG_THREAD_STACK_SIZE)

Functions
ssp_err_t	SF_AUDIO_PLAYBACK_Open (sf_audio_playback_ctrl_t *const p_api_ctrl, sf_audio_playback_cfg_t const *const p_cfg)
ssp_err_t	SF_AUDIO_PLAYBACK_Close (sf_audio_playback_ctrl_t *const p_api_ctrl)
ssp_err_t	SF_AUDIO_PLAYBACK_Start (sf_audio_playback_ctrl_t *const p_api_ctrl, sf_audio_playback_data_t *const p_data, UINT const timeout)
ssp_err_t	SF_AUDIO_PLAYBACK_Pause (sf_audio_playback_ctrl_t *const p_api_ctrl)
ssp_err_t	SF_AUDIO_PLAYBACK_Stop (sf_audio_playback_ctrl_t *const p_api_ctrl)
ssp_err_t	SF_AUDIO_PLAYBACK_Resume (sf_audio_playback_ctrl_t *const p_api_ctrl)
ssp_err_t	SF_AUDIO_PLAYBACK_VolumeSet (sf_audio_playback_ctrl_t *const p_api_ctrl, uint8_t const volume)
ssp_err_t	SF_AUDIO_PLAYBACK_VersionGet (ssp_version_t *const p_version)

Detailed Description

RTOS-integrated Audio Framework.

Summary

This module is a ThreadX-aware Audio Framework. The module implements Audio Framework Interface.

Name of module used by error logger macro

Macro Definition Documentation

SF_AUDIO_PLAYBACK_CODE_VERSION_MAJOR

#define SF_AUDIO_PLAYBACK_CODE_VERSION_MAJOR   (2U)

Version of code that implements the API defined in this file

SF_AUDIO_PLAYBACK_STACK_SIZE

#define SF_AUDIO_PLAYBACK_STACK_SIZE   (SF_AUDIO_PLAYBACK_CFG_THREAD_STACK_SIZE)

Audio playback internal thread stack size. Varies by application, but rarely requires more than 256 bytes.

Function Documentation

SF_AUDIO_PLAYBACK_Close()

ssp_err_t SF_AUDIO_PLAYBACK_Close

(

sf_audio_playback_ctrl_t *const

p_api_ctrl

)

Implements sf_audio_playback_api_t::close.

Return values

SSP_SUCCESS	Audio instance successfully closed
SSP_ERR_ASSERTION	p_ctrl is NULL
SSP_ERR_NOT_OPEN	The stream control block p_ctrl is not initialized.

Returns

See Common Error Codes or lower level drivers for other possible return codes.

Note

This function is not reentrant.

Mark stream as unused in hardware control block and determine if all streams are closed.

Mark hardware control block as unused so it can be reconfigured.

Close lower level drivers

Delete RTOS services used

Mark control block as unused so it can be reconfigured.

SF_AUDIO_PLAYBACK_Open()

ssp_err_t SF_AUDIO_PLAYBACK_Open	(	sf_audio_playback_ctrl_t *const	p_api_ctrl,
		sf_audio_playback_cfg_t const *const	p_cfg
	)

Implements sf_audio_playback_api_t::open.

Return values

SSP_SUCCESS	Audio hardware successfully configured.
SSP_ERR_ASSERTION	A pointer is NULL or a parameter is invalid.
SSP_ERR_OUT_OF_MEMORY	The number of streams open at once is limited to SF_AUDIO_PLAYBACK_CFG_MAX_STREAMS. If this number is exceeded, an out of memory error occurs.
SSP_ERR_INTERNAL	An internal ThreadX error has occurred. This is typically a failure to create/use a mutex.

Returns

See Common Error Codes or lower level drivers for other possible return codes.

Note

This function is not reentrant.

Open hardware if it is not already open.

Enter a critical section before checking the common instance mutex status.

Check if common instance mutex is already created. If not then create the mutex.

Create common_instance_mutex to protect common initialization, including initialization of shared event flags, audio playback thread and lower level hardware.

If mutex create fails, return error.

Exit critical section

Acquire the mutex before accessing the shared resource. Try again if the mutex was deleted in close.

Create event flags to notify playback thread when playback of a buffer is complete.

Store stream pointer in common control block.

Release the mutex.

Mark stream opened so it can be used by other API's.

SF_AUDIO_PLAYBACK_Pause()

ssp_err_t SF_AUDIO_PLAYBACK_Pause

(

sf_audio_playback_ctrl_t *const

p_api_ctrl

)

Implements sf_audio_playback_api_t::pause.

Return values

SSP_SUCCESS	Audio playback pause message sent to audio playback thread for this stream.
SSP_ERR_ASSERTION	p_ctrl is NULL
SSP_ERR_NOT_OPEN	The stream control block p_ctrl is not initialized.

Returns

See Common Error Codes or lower level drivers for other possible return codes.

Note

This function is reentrant.

Send message with pause event to audio thread.

SF_AUDIO_PLAYBACK_Resume()

ssp_err_t SF_AUDIO_PLAYBACK_Resume

(

sf_audio_playback_ctrl_t *const

p_api_ctrl

)

Implements sf_audio_playback_api_t::resume.

Return values

SSP_SUCCESS	Audio playback resume message sent to audio playback thread for this stream.
SSP_ERR_ASSERTION	p_ctrl is NULL
SSP_ERR_NOT_OPEN	The stream control block p_ctrl is not initialized.

Note

This function is reentrant.

Send message with resume event to audio thread.

SF_AUDIO_PLAYBACK_Start()

ssp_err_t SF_AUDIO_PLAYBACK_Start	(	sf_audio_playback_ctrl_t *const	p_api_ctrl,
		sf_audio_playback_data_t *const	p_data,
		UINT const	timeout
	)

Implements sf_audio_playback_api_t::start.

Return values

SSP_SUCCESS	Buffer successfully sent to audio playback thread
SSP_ERR_ASSERTION	p_ctrl is NULL
SSP_ERR_NOT_OPEN	The stream control block p_ctrl is not initialized.

Note

This function is reentrant.

Ensure that audio data is only posted from the current stream owner.

Store new stream owner if stream is unowned.

Set message header to audio start event. Set instance to stream instance.

Send message with audio data to audio thread.

SF_AUDIO_PLAYBACK_Stop()

ssp_err_t SF_AUDIO_PLAYBACK_Stop

(

sf_audio_playback_ctrl_t *const

p_api_ctrl

)

Implements sf_audio_playback_api_t::stop.

Return values

SSP_SUCCESS	Audio playback stop message sent to audio playback thread for this stream.
SSP_ERR_ASSERTION	p_ctrl is NULL
SSP_ERR_NOT_OPEN	The stream control block p_ctrl is not initialized.

Returns

See Common Error Codes or lower level drivers for other possible return codes.

Note

This function is reentrant.

Send message with stop event to audio thread.

SF_AUDIO_PLAYBACK_VersionGet()

ssp_err_t SF_AUDIO_PLAYBACK_VersionGet

(

ssp_version_t *const

p_version

)

Implements sf_audio_playback_api_t::versionGet.

Return values

SSP_SUCCESS	Version returned successfully.
SSP_ERR_ASSERTION	Parameter p_version was null.

SF_AUDIO_PLAYBACK_VolumeSet()

ssp_err_t SF_AUDIO_PLAYBACK_VolumeSet	(	sf_audio_playback_ctrl_t *const	p_api_ctrl,
		uint8_t const	volume
	)

Implements sf_audio_playback_api_t::volumeSet.

Return values

SSP_SUCCESS	Audio playback software volume level updated (applies to all streams).
SSP_ERR_ASSERTION	p_ctrl is NULL
SSP_ERR_NOT_OPEN	The stream control block p_ctrl is not initialized.

Update volume in control block.