UART DMA Driver

Overview

Files
file	fsl_uart_dma.h

Data Structures
struct	uart_dma_handle_t
	UART DMA handle. More...

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

EDMA transactional
void	UART_TransferCreateHandleDMA (UART_Type *base, uart_dma_handle_t *handle, uart_dma_transfer_callback_t callback, void *userData, dma_handle_t *txDmaHandle, dma_handle_t *rxDmaHandle)
	Initializes the UART handle which is used in transactional functions and sets the callback. More...
status_t	UART_TransferSendDMA (UART_Type *base, uart_dma_handle_t *handle, uart_transfer_t *xfer)
	Sends data using DMA. More...
status_t	UART_TransferReceiveDMA (UART_Type *base, uart_dma_handle_t *handle, uart_transfer_t *xfer)
	Receives data using DMA. More...
void	UART_TransferAbortSendDMA (UART_Type *base, uart_dma_handle_t *handle)
	Aborts the send data using DMA. More...
void	UART_TransferAbortReceiveDMA (UART_Type *base, uart_dma_handle_t *handle)
	Aborts the received data using DMA. More...
status_t	UART_TransferGetSendCountDMA (UART_Type *base, uart_dma_handle_t *handle, uint32_t *count)
	Get the number of bytes that have been written to UART TX register. More...
status_t	UART_TransferGetReceiveCountDMA (UART_Type *base, uart_dma_handle_t *handle, uint32_t *count)
	Get the number of bytes that have been received. More...

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Data Structure Documentation

struct _uart_dma_handle

Data Fields
UART_Type *	base
	UART peripheral base address. More...
uart_dma_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...
dma_handle_t *	txDmaHandle
	The DMA TX channel used. More...
dma_handle_t *	rxDmaHandle
	The DMA RX channel used. More...
volatile uint8_t	txState
	TX transfer state. More...
volatile uint8_t	rxState
	RX transfer state.

Field Documentation

UART_Type* uart_dma_handle_t::base

uart_dma_transfer_callback_t uart_dma_handle_t::callback

void* uart_dma_handle_t::userData

size_t uart_dma_handle_t::rxDataSizeAll

size_t uart_dma_handle_t::txDataSizeAll

dma_handle_t* uart_dma_handle_t::txDmaHandle

dma_handle_t* uart_dma_handle_t::rxDmaHandle

volatile uint8_t uart_dma_handle_t::txState

Typedef Documentation

typedef void(* uart_dma_transfer_callback_t)(UART_Type *base, uart_dma_handle_t *handle, status_t status, void *userData)

Function Documentation

void UART_TransferCreateHandleDMA	(	UART_Type *	base,
		uart_dma_handle_t *	handle,
		uart_dma_transfer_callback_t	callback,
		void *	userData,
		dma_handle_t *	txDmaHandle,
		dma_handle_t *	rxDmaHandle
	)

Parameters

base	UART peripheral base address.
handle	Pointer to uart_dma_handle_t structure.
callback	UART callback, NULL means no callback.
userData	User callback function data.
rxDmaHandle	User requested DMA handle for RX DMA transfer.
txDmaHandle	User requested DMA handle for TX DMA transfer.

status_t UART_TransferSendDMA	(	UART_Type *	base,
		uart_dma_handle_t *	handle,
		uart_transfer_t *	xfer
	)

This function sends data using DMA. This is 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 DMA transfer structure. See uart_transfer_t.

Return values

kStatus_Success	if succeed, others failed.
kStatus_UART_TxBusy	Previous transfer on going.
kStatus_InvalidArgument	Invalid argument.

status_t UART_TransferReceiveDMA	(	UART_Type *	base,
		uart_dma_handle_t *	handle,
		uart_transfer_t *	xfer
	)

This function receives data using DMA. This is 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 uart_dma_handle_t structure.
xfer	UART DMA transfer structure. See uart_transfer_t.

Return values

kStatus_Success	if succeed, others failed.
kStatus_UART_RxBusy	Previous transfer on going.
kStatus_InvalidArgument	Invalid argument.

void UART_TransferAbortSendDMA	(	UART_Type *	base,
		uart_dma_handle_t *	handle
	)

This function aborts the sent data using DMA.

Parameters

base	UART peripheral base address.
handle	Pointer to uart_dma_handle_t structure.

void UART_TransferAbortReceiveDMA	(	UART_Type *	base,
		uart_dma_handle_t *	handle
	)

This function abort receive data which using DMA.

Parameters

base	UART peripheral base address.
handle	Pointer to uart_dma_handle_t structure.

status_t UART_TransferGetSendCountDMA	(	UART_Type *	base,
		uart_dma_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_TransferGetReceiveCountDMA	(	UART_Type *	base,
		uart_dma_handle_t *	handle,
		uint32_t *	count
	)

This function gets the number of bytes that have been received.

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;