UART eDMA Driver

Overview

Data Structures
struct	uart_edma_handle_t
	UART eDMA handle. More...

Typedefs
typedef void(*	uart_edma_transfer_callback_t )(UART_Type *base, uart_edma_handle_t *handle, status_t status, void *userData)
	UART transfer callback function. More...

eDMA transactional
void	UART_TransferCreateHandleEDMA (UART_Type *base, uart_edma_handle_t *handle, uart_edma_transfer_callback_t callback, void *userData, edma_handle_t *txEdmaHandle, edma_handle_t *rxEdmaHandle)
	Initializes the UART handle which is used in transactional functions. More...
status_t	UART_SendEDMA (UART_Type *base, uart_edma_handle_t *handle, uart_transfer_t *xfer)
	Sends data using eDMA. More...
status_t	UART_ReceiveEDMA (UART_Type *base, uart_edma_handle_t *handle, uart_transfer_t *xfer)
	Receives data using eDMA. More...
void	UART_TransferAbortSendEDMA (UART_Type *base, uart_edma_handle_t *handle)
	Aborts the sent data using eDMA. More...
void	UART_TransferAbortReceiveEDMA (UART_Type *base, uart_edma_handle_t *handle)
	Aborts the receive data using eDMA. More...
status_t	UART_TransferGetSendCountEDMA (UART_Type *base, uart_edma_handle_t *handle, uint32_t *count)
	Gets the number of bytes that have been written to UART TX register. More...
status_t	UART_TransferGetReceiveCountEDMA (UART_Type *base, uart_edma_handle_t *handle, uint32_t *count)
	Gets the number of received bytes. More...

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Data Structure Documentation

struct _uart_edma_handle

Data Fields
uart_edma_transfer_callback_t	callback
	Callback function. More...
void *	userData
	UART callback function parameter. More...
size_t	rxDataSizeAll
	Size of the data to receive. More...
size_t	txDataSizeAll
	Size of the data to send out. More...
edma_handle_t *	txEdmaHandle
	The eDMA TX channel used. More...
edma_handle_t *	rxEdmaHandle
	The eDMA RX channel used. More...
uint8_t	nbytes
	eDMA minor byte transfer count initially configured. More...
volatile uint8_t	txState
	TX transfer state. More...
volatile uint8_t	rxState
	RX transfer state.

Field Documentation

uart_edma_transfer_callback_t uart_edma_handle_t::callback

void* uart_edma_handle_t::userData

size_t uart_edma_handle_t::rxDataSizeAll

size_t uart_edma_handle_t::txDataSizeAll

edma_handle_t* uart_edma_handle_t::txEdmaHandle

edma_handle_t* uart_edma_handle_t::rxEdmaHandle

uint8_t uart_edma_handle_t::nbytes

volatile uint8_t uart_edma_handle_t::txState

Typedef Documentation

typedef void(* uart_edma_transfer_callback_t)(UART_Type *base, uart_edma_handle_t *handle, status_t status, void *userData)

Function Documentation

void UART_TransferCreateHandleEDMA	(	UART_Type *	base,
		uart_edma_handle_t *	handle,
		uart_edma_transfer_callback_t	callback,
		void *	userData,
		edma_handle_t *	txEdmaHandle,
		edma_handle_t *	rxEdmaHandle
	)

Parameters

base	UART peripheral base address.
handle	Pointer to the uart_edma_handle_t structure.
callback	UART callback, NULL means no callback.
userData	User callback function data.
rxEdmaHandle	User-requested DMA handle for RX DMA transfer.
txEdmaHandle	User-requested DMA handle for TX DMA transfer.

status_t UART_SendEDMA	(	UART_Type *	base,
		uart_edma_handle_t *	handle,
		uart_transfer_t *	xfer
	)

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

Parameters

base	UART peripheral base address.
handle	UART handle pointer.
xfer	UART eDMA transfer structure. See uart_transfer_t.

Return values

kStatus_Success	if succeeded; otherwise failed.
kStatus_UART_TxBusy	Previous transfer ongoing.
kStatus_InvalidArgument	Invalid argument.

status_t UART_ReceiveEDMA	(	UART_Type *	base,
		uart_edma_handle_t *	handle,
		uart_transfer_t *	xfer
	)

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

Parameters

base	UART peripheral base address.
handle	Pointer to the uart_edma_handle_t structure.
xfer	UART eDMA transfer structure. See uart_transfer_t.

Return values

kStatus_Success	if succeeded; otherwise failed.
kStatus_UART_RxBusy	Previous transfer ongoing.
kStatus_InvalidArgument	Invalid argument.

void UART_TransferAbortSendEDMA	(	UART_Type *	base,
		uart_edma_handle_t *	handle
	)

This function aborts sent data using eDMA.

Parameters

base	UART peripheral base address.
handle	Pointer to the uart_edma_handle_t structure.

void UART_TransferAbortReceiveEDMA	(	UART_Type *	base,
		uart_edma_handle_t *	handle
	)

This function aborts receive data using eDMA.

Parameters

base	UART peripheral base address.
handle	Pointer to the uart_edma_handle_t structure.

status_t UART_TransferGetSendCountEDMA	(	UART_Type *	base,
		uart_edma_handle_t *	handle,
		uint32_t *	count
	)

This function gets the number of bytes that have been written to UART TX register by DMA.

Parameters

base	UART peripheral base address.
handle	UART handle pointer.
count	Send bytes count.

Return values

kStatus_NoTransferInProgress	No send in progress.
kStatus_InvalidArgument	Parameter is invalid.
kStatus_Success	Get successfully through the parameter count;

status_t UART_TransferGetReceiveCountEDMA	(	UART_Type *	base,
		uart_edma_handle_t *	handle,
		uint32_t *	count
	)

This function gets the number of received bytes.

Parameters

base	UART peripheral base address.
handle	UART handle pointer.
count	Receive bytes count.

Return values

kStatus_NoTransferInProgress	No receive in progress.
kStatus_InvalidArgument	Parameter is invalid.
kStatus_Success	Get successfully through the parameter count;