DSPI eDMA Driver

Overview

This section describes the programming interface of the DSPI Peripheral driver. The DSPI driver configures DSPI module and provides the functional and transactional interfaces to build the DSPI application.

Data Structures
struct	dspi_master_edma_handle_t
	DSPI master eDMA transfer handle structure used for the transactional API. More...
struct	dspi_slave_edma_handle_t
	DSPI slave eDMA transfer handle structure used for the transactional API. More...

Typedefs
typedef void(*	dspi_master_edma_transfer_callback_t )(SPI_Type *base, dspi_master_edma_handle_t *handle, status_t status, void *userData)
	Completion callback function pointer type. More...
typedef void(*	dspi_slave_edma_transfer_callback_t )(SPI_Type *base, dspi_slave_edma_handle_t *handle, status_t status, void *userData)
	Completion callback function pointer type. More...

Functions
void	DSPI_MasterTransferCreateHandleEDMA (SPI_Type *base, dspi_master_edma_handle_t *handle, dspi_master_edma_transfer_callback_t callback, void *userData, edma_handle_t *edmaRxRegToRxDataHandle, edma_handle_t *edmaTxDataToIntermediaryHandle, edma_handle_t *edmaIntermediaryToTxRegHandle)
	Initializes the DSPI master eDMA handle. More...
status_t	DSPI_MasterTransferEDMA (SPI_Type *base, dspi_master_edma_handle_t *handle, dspi_transfer_t *transfer)
	DSPI master transfer data using eDMA. More...
void	DSPI_MasterTransferAbortEDMA (SPI_Type *base, dspi_master_edma_handle_t *handle)
	DSPI master aborts a transfer which is using eDMA. More...
status_t	DSPI_MasterTransferGetCountEDMA (SPI_Type *base, dspi_master_edma_handle_t *handle, size_t *count)
	Gets the master eDMA transfer count. More...
void	DSPI_SlaveTransferCreateHandleEDMA (SPI_Type *base, dspi_slave_edma_handle_t *handle, dspi_slave_edma_transfer_callback_t callback, void *userData, edma_handle_t *edmaRxRegToRxDataHandle, edma_handle_t *edmaTxDataToTxRegHandle)
	Initializes the DSPI slave eDMA handle. More...
status_t	DSPI_SlaveTransferEDMA (SPI_Type *base, dspi_slave_edma_handle_t *handle, dspi_transfer_t *transfer)
	DSPI slave transfer data using eDMA. More...
void	DSPI_SlaveTransferAbortEDMA (SPI_Type *base, dspi_slave_edma_handle_t *handle)
	DSPI slave aborts a transfer which is using eDMA. More...
status_t	DSPI_SlaveTransferGetCountEDMA (SPI_Type *base, dspi_slave_edma_handle_t *handle, size_t *count)
	Gets the slave eDMA transfer count. More...

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Data Structure Documentation

struct _dspi_master_edma_handle

Forward declaration of the DSPI eDMA master handle typedefs.

Data Fields
uint32_t	bitsPerFrame
	The desired number of bits per frame. More...
volatile uint32_t	command
	The desired data command. More...
volatile uint32_t	lastCommand
	The desired last data command. More...
uint8_t	fifoSize
	FIFO dataSize. More...
volatile bool	isPcsActiveAfterTransfer
	Indicates whether the PCS signal keeps active after the last frame transfer. More...
uint8_t	nbytes
	eDMA minor byte transfer count initially configured. More...
volatile uint8_t	state
	DSPI transfer state , _dspi_transfer_state. More...
uint8_t *volatile	txData
	Send buffer. More...
uint8_t *volatile	rxData
	Receive buffer. More...
volatile size_t	remainingSendByteCount
	A number of bytes remaining to send. More...
volatile size_t	remainingReceiveByteCount
	A number of bytes remaining to receive. More...
size_t	totalByteCount
	A number of transfer bytes.
uint32_t	rxBuffIfNull
	Used if there is not rxData for DMA purpose. More...
uint32_t	txBuffIfNull
	Used if there is not txData for DMA purpose. More...
dspi_master_edma_transfer_callback_t	callback
	Completion callback. More...
void *	userData
	Callback user data. More...
edma_handle_t *	edmaRxRegToRxDataHandle
	edma_handle_t handle point used for RxReg to RxData buff
edma_handle_t *	edmaTxDataToIntermediaryHandle
	edma_handle_t handle point used for TxData to Intermediary
edma_handle_t *	edmaIntermediaryToTxRegHandle
	edma_handle_t handle point used for Intermediary to TxReg
edma_tcd_t	dspiSoftwareTCD [2]
	SoftwareTCD , internal used.

Field Documentation

uint32_t dspi_master_edma_handle_t::bitsPerFrame

volatile uint32_t dspi_master_edma_handle_t::command

volatile uint32_t dspi_master_edma_handle_t::lastCommand

uint8_t dspi_master_edma_handle_t::fifoSize

volatile bool dspi_master_edma_handle_t::isPcsActiveAfterTransfer

uint8_t dspi_master_edma_handle_t::nbytes

volatile uint8_t dspi_master_edma_handle_t::state

uint8_t* volatile dspi_master_edma_handle_t::txData

uint8_t* volatile dspi_master_edma_handle_t::rxData

volatile size_t dspi_master_edma_handle_t::remainingSendByteCount

volatile size_t dspi_master_edma_handle_t::remainingReceiveByteCount

uint32_t dspi_master_edma_handle_t::rxBuffIfNull

uint32_t dspi_master_edma_handle_t::txBuffIfNull

dspi_master_edma_transfer_callback_t dspi_master_edma_handle_t::callback

void* dspi_master_edma_handle_t::userData

struct _dspi_slave_edma_handle

Forward declaration of the DSPI eDMA slave handle typedefs.

Data Fields
uint32_t	bitsPerFrame
	The desired number of bits per frame. More...
uint8_t *volatile	txData
	Send buffer. More...
uint8_t *volatile	rxData
	Receive buffer. More...
volatile size_t	remainingSendByteCount
	A number of bytes remaining to send. More...
volatile size_t	remainingReceiveByteCount
	A number of bytes remaining to receive. More...
size_t	totalByteCount
	A number of transfer bytes.
uint32_t	rxBuffIfNull
	Used if there is not rxData for DMA purpose. More...
uint32_t	txBuffIfNull
	Used if there is not txData for DMA purpose. More...
uint32_t	txLastData
	Used if there is an extra byte when 16bits per frame for DMA purpose. More...
uint8_t	nbytes
	eDMA minor byte transfer count initially configured. More...
volatile uint8_t	state
	DSPI transfer state. More...
dspi_slave_edma_transfer_callback_t	callback
	Completion callback. More...
void *	userData
	Callback user data. More...
edma_handle_t *	edmaRxRegToRxDataHandle
	edma_handle_t handle point used for RxReg to RxData buff
edma_handle_t *	edmaTxDataToTxRegHandle
	edma_handle_t handle point used for TxData to TxReg

Field Documentation

uint32_t dspi_slave_edma_handle_t::bitsPerFrame

uint8_t* volatile dspi_slave_edma_handle_t::txData

uint8_t* volatile dspi_slave_edma_handle_t::rxData

volatile size_t dspi_slave_edma_handle_t::remainingSendByteCount

volatile size_t dspi_slave_edma_handle_t::remainingReceiveByteCount

uint32_t dspi_slave_edma_handle_t::rxBuffIfNull

uint32_t dspi_slave_edma_handle_t::txBuffIfNull

uint32_t dspi_slave_edma_handle_t::txLastData

uint8_t dspi_slave_edma_handle_t::nbytes

volatile uint8_t dspi_slave_edma_handle_t::state

dspi_slave_edma_transfer_callback_t dspi_slave_edma_handle_t::callback

void* dspi_slave_edma_handle_t::userData

Typedef Documentation

typedef void(* dspi_master_edma_transfer_callback_t)(SPI_Type *base, dspi_master_edma_handle_t *handle, status_t status, void *userData)

Parameters

base	DSPI peripheral base address.
handle	A pointer to the handle for the DSPI master.
status	Success or error code describing whether the transfer completed.
userData	An arbitrary pointer-dataSized value passed from the application.

typedef void(* dspi_slave_edma_transfer_callback_t)(SPI_Type *base, dspi_slave_edma_handle_t *handle, status_t status, void *userData)

Parameters

base	DSPI peripheral base address.
handle	A pointer to the handle for the DSPI slave.
status	Success or error code describing whether the transfer completed.
userData	An arbitrary pointer-dataSized value passed from the application.

Function Documentation

void DSPI_MasterTransferCreateHandleEDMA	(	SPI_Type *	base,
		dspi_master_edma_handle_t *	handle,
		dspi_master_edma_transfer_callback_t	callback,
		void *	userData,
		edma_handle_t *	edmaRxRegToRxDataHandle,
		edma_handle_t *	edmaTxDataToIntermediaryHandle,
		edma_handle_t *	edmaIntermediaryToTxRegHandle
	)

This function initializes the DSPI eDMA handle which can be used for other DSPI transactional APIs. Usually, for a specified DSPI instance, call this API once to get the initialized handle.

Note that DSPI eDMA has separated (RX and TX as two sources) or shared (RX and TX are the same source) DMA request source. (1) For the separated DMA request source, enable and set the RX DMAMUX source for edmaRxRegToRxDataHandle and TX DMAMUX source for edmaIntermediaryToTxRegHandle. (2) For the shared DMA request source, enable and set the RX/RX DMAMUX source for the edmaRxRegToRxDataHandle.

Parameters

base	DSPI peripheral base address.
handle	DSPI handle pointer to dspi_master_edma_handle_t.
callback	DSPI callback.
userData	A callback function parameter.
edmaRxRegToRxDataHandle	edmaRxRegToRxDataHandle pointer to edma_handle_t.
edmaTxDataToIntermediaryHandle	edmaTxDataToIntermediaryHandle pointer to edma_handle_t.
edmaIntermediaryToTxRegHandle	edmaIntermediaryToTxRegHandle pointer to edma_handle_t.

status_t DSPI_MasterTransferEDMA	(	SPI_Type *	base,
		dspi_master_edma_handle_t *	handle,
		dspi_transfer_t *	transfer
	)

This function transfers data using eDMA. This is a non-blocking function, which returns right away. When all data is transferred, the callback function is called.

Parameters

base	DSPI peripheral base address.
handle	A pointer to the dspi_master_edma_handle_t structure which stores the transfer state.
transfer	A pointer to the dspi_transfer_t structure.

Returns

status of status_t.

void DSPI_MasterTransferAbortEDMA	(	SPI_Type *	base,
		dspi_master_edma_handle_t *	handle
	)

This function aborts a transfer which is using eDMA.

Parameters

base	DSPI peripheral base address.
handle	A pointer to the dspi_master_edma_handle_t structure which stores the transfer state.

status_t DSPI_MasterTransferGetCountEDMA	(	SPI_Type *	base,
		dspi_master_edma_handle_t *	handle,
		size_t *	count
	)

This function gets the master eDMA transfer count.

Parameters

base	DSPI peripheral base address.
handle	A pointer to the dspi_master_edma_handle_t structure which stores the transfer state.
count	A number of bytes transferred by the non-blocking transaction.

Returns

status of status_t.

void DSPI_SlaveTransferCreateHandleEDMA	(	SPI_Type *	base,
		dspi_slave_edma_handle_t *	handle,
		dspi_slave_edma_transfer_callback_t	callback,
		void *	userData,
		edma_handle_t *	edmaRxRegToRxDataHandle,
		edma_handle_t *	edmaTxDataToTxRegHandle
	)

This function initializes the DSPI eDMA handle which can be used for other DSPI transactional APIs. Usually, for a specified DSPI instance, call this API once to get the initialized handle.

Note that DSPI eDMA has separated (RN and TX in 2 sources) or shared (RX and TX are the same source) DMA request source. (1)For the separated DMA request source, enable and set the RX DMAMUX source for edmaRxRegToRxDataHandle and TX DMAMUX source for edmaTxDataToTxRegHandle. (2)For the shared DMA request source, enable and set the RX/RX DMAMUX source for the edmaRxRegToRxDataHandle.

Parameters

base	DSPI peripheral base address.
handle	DSPI handle pointer to dspi_slave_edma_handle_t.
callback	DSPI callback.
userData	A callback function parameter.
edmaRxRegToRxDataHandle	edmaRxRegToRxDataHandle pointer to edma_handle_t.
edmaTxDataToTxRegHandle	edmaTxDataToTxRegHandle pointer to edma_handle_t.

status_t DSPI_SlaveTransferEDMA	(	SPI_Type *	base,
		dspi_slave_edma_handle_t *	handle,
		dspi_transfer_t *	transfer
	)

This function transfers data using eDMA. This is a non-blocking function, which returns right away. When all data is transferred, the callback function is called. Note that the slave eDMA transfer doesn't support transfer_size is 1 when the bitsPerFrame is greater than eight.

Parameters

base	DSPI peripheral base address.
handle	A pointer to the dspi_slave_edma_handle_t structure which stores the transfer state.
transfer	A pointer to the dspi_transfer_t structure.

Returns

status of status_t.

void DSPI_SlaveTransferAbortEDMA	(	SPI_Type *	base,
		dspi_slave_edma_handle_t *	handle
	)

This function aborts a transfer which is using eDMA.

Parameters

base	DSPI peripheral base address.
handle	A pointer to the dspi_slave_edma_handle_t structure which stores the transfer state.

status_t DSPI_SlaveTransferGetCountEDMA	(	SPI_Type *	base,
		dspi_slave_edma_handle_t *	handle,
		size_t *	count
	)

This function gets the slave eDMA transfer count.

Parameters

base	DSPI peripheral base address.
handle	A pointer to the dspi_slave_edma_handle_t structure which stores the transfer state.
count	A number of bytes transferred so far by the non-blocking transaction.

Returns

status of status_t.