streamer_element.h File Reference

Header for Streamer Element. More...

#include "streamer_api.h"
#include "pad.h"

Data Structures
struct	StreamElement
	Stream Element. More...
struct	ElementInit

Macros
#define	ELEMENT_PARENT_PIPELINE(pstelem)   ((Pipeline *)((pstelem)->parent))
	Get element parent pipeline.
#define	ELEMENT_PARENT(pstelem)   ((pstelem)->parent)
	Get element parent (void)
#define	ELEMENT_KEY(pstelem)   ((pstelem)->key)
	Get element key.
#define	ELEMENT_DEPTH(pstelem)   ((pstelem)->depth)
	Get element depth.
#define	ELEMENT_TYPE(pstelem)   ((pstelem)->type)
	Get element type.
#define	ELEMENT_STATE(pstelem)   ((pstelem)->state)
	Get element state.
#define	ELEMENT_SIBLING(pstelem)   ((pstelem)->sibling)
	Get element sibling.
#define	ELEMENT_SRC_PAD(pstelem, i)   ((StreamPad *)&(pstelem)->src_pad[i])
	Get element source pad.
#define	ELEMENT_SINK_PAD(pstelem, i)   ((StreamPad *)&(pstelem)->sink_pad[i])
	Get element sink pad.
#define	MAX_NUM_PADS   (3)
	Maximum number of pads.
#define	MAX_LOCATION_PATH_LENGTH   (255)
	Maximum location path length.
#define	MAX_DEVICE_NAME_LENGTH   (32)
	Maximum device name length.
#define	AUDIO_SET_FORMAT(a, b, c, d)   (((d << 4) & 0xFF0) | ((c << 2) & 0x4) | ((b << 1) & 0x2) | ((a << 0) & 0x1))

Functions
uint8_t	activate_pads_element (StreamElement *element, uint8_t activate)
	activate_pads_element More...
int32_t	create_element (ElementHandle *handle, StreamElementType type, int8_t key)
	create_element More...
int32_t	destroy_element (ElementHandle handle)
	destroy_element More...
int32_t	link_elements (ElementHandle src_handle, int8_t src_pad_index, ElementHandle sink_handle, int8_t sink_pad_index)
	link_elements More...
int32_t	unlink_elements (ElementHandle src_handle, int8_t src_pad_index, ElementHandle sink_handle, int8_t sink_pad_index)
	unlink_elements More...
int32_t	get_element_info (ElementHandle handle, StreamElementType *ptype, int8_t *pkey)
	get_element_info: More...
int32_t	send_msg_element (StreamElement *element, uint32_t msg, uintptr_t data)
	send_msg_element More...
int32_t	element_get_property (ElementHandle element_hdl, uint16_t prop, uint64_t *val_ptr)
	This function gets property value of element. More...
int32_t	element_set_property (ElementHandle element_hdl, uint16_t prop, uintptr_t val)
	this function sets property value of element More...

Macro Definition Documentation

AUDIO_SET_FORMAT

#define AUDIO_SET_FORMAT	(		a,
			b,
			c,
			d
	)		(((d << 4) & 0xFF0) | ((c << 2) & 0x4) | ((b << 1) & 0x2) | ((a << 0) & 0x1))

AUDIO_SET_FORMAT: Set output format a- interleaved b- endianness c- signed d- word length

Function Documentation

activate_pads_element()

uint8_t activate_pads_element	(	StreamElement *	element,
		uint8_t	activate
	)

This function iterates through all the pads of the elements, first src pads and then sink, and calls the activate pad function.

Parameters

element	Pointer to element handle
activate	Activate or Deactivate the pads?

Returns

bool

create_element()

int32_t create_element	(	ElementHandle *	handle,
		StreamElementType	type,
		int8_t	key
	)

Creates a new element of the required type. A byte key which should be unique within the same type of element.

Parameters

handle	Pointer to element handle
type	Element type
key	Unique key within the same type of elements to retrieve the handle from the pipeline later.

Returns

Error Status

Return values

STREAM_OK	Element created successfully
STREAM_ERR_NO_MEM	Error allocating memory
STREAM_ERR_ELEMENT_NOT_FOUND	Element type not found

destroy_element()

int32_t destroy_element

(

ElementHandle

handle

)

Function to destroy element. Make sure that this element is not linked to any other element and not a part of pipeline.

Parameters

handle

Element handle

Returns

Error Status

Return values

STREAM_OK	Element successfully destroyed
STREAM_ERR_ELEMENT_NOT_FREE	Element still associated with a pipeline
STREAM_ERR_INVALID_ARGS	Invalid element object

link_elements()

int32_t link_elements	(	ElementHandle	src_handle,
		int8_t	src_pad_index,
		ElementHandle	sink_handle,
		int8_t	sink_pad_index
	)

Link elements from the source pad to sink pad.

Parameters

src_handle	Element with the source pad.
src_pad_index	Index of the source pad of element.
sink_handle	Element with the sink pad.
sink_pad_index	Index of the sink pad of element.

Returns

Error Status

Return values

STREAM_OK	Elements linked successfully
STREAM_ERR_INVALID_ARGS	Invalid argument
STREAM_ERR_ELEMENT_LINKED	Element already linked

unlink_elements()

int32_t unlink_elements	(	ElementHandle	src_handle,
		int8_t	src_pad_index,
		ElementHandle	sink_handle,
		int8_t	sink_pad_index
	)

Unlink elements from the source pad to sink pad.

Parameters

src_handle	Element with the source pad.
src_pad_index	Index of the source pad of element.
sink_handle	Element with the sink pad.
sink_pad_index	Index of the sink pad of element.

Returns

Error Status

Return values

STREAM_OK	Elements unlinked successfully
STREAM_ERR_ELEMENT_PADS_NOT_LINKED	Elements not linked
STREAM_ERR_INVALID_ARGS	Invalid arguments

get_element_info()

int32_t get_element_info	(	ElementHandle	handle,
		StreamElementType *	ptype,
		int8_t *	pkey
	)

Function to return the element info.

Parameters

handle	Element handle
ptype	ElementType pointer to return the element type
pkey	int8_t pointer to return the uinque element key

Returns

Error Status

Return values

STREAM_OK	Element info successfully retrieved
STREAM_ERR_INVALID_ARGS	Invalid argument provided

send_msg_element()

int32_t send_msg_element	(	StreamElement *	element,
		uint32_t	msg,
		uintptr_t	data
	)

The function creates and sends a message to the parent pipeline

Parameters

element	Element from which the message is sent from
msg	StreamMessage type
data	Data associated with the message

Returns

Error Status

Return values

STREAM_OK	Message sent successfully
STREAM_ERR_INVALID_ARGS	Invalid element/pipeline object

element_get_property()

int32_t element_get_property	(	ElementHandle	element_hdl,
		uint16_t	prop,
		uint64_t *	val_ptr
	)

Parameters

element_hdl	element handle
prop	property id
val_ptr	pointer to the address of value

Returns

int32_t error codes

element_set_property()

int32_t element_set_property	(	ElementHandle	element_hdl,
		uint16_t	prop,
		uintptr_t	val
	)

Parameters

element_hdl	element handle
prop	property id
val	value to be set

Returns

int32_t error codes