DMIC DMA Driver

Overview

Files
file	fsl_dmic_dma.h

Data Structures
struct	dmic_transfer_t
	DMIC transfer structure. More...
struct	dmic_dma_handle_t
	DMIC DMA handle. More...

Typedefs
typedef void(*	dmic_dma_transfer_callback_t )(DMIC_Type *base, dmic_dma_handle_t *handle, status_t status, void *userData)
	DMIC transfer callback function. More...

DMIC DMA version
#define	FSL_DMIC_DMA_DRIVER_VERSION   (MAKE_VERSION(2, 2, 0))
	DMIC DMA driver version 2.2.0.

DMA transactional
status_t	DMIC_TransferCreateHandleDMA (DMIC_Type *base, dmic_dma_handle_t *handle, dmic_dma_transfer_callback_t callback, void *userData, dma_handle_t *rxDmaHandle)
	Initializes the DMIC handle which is used in transactional functions. More...
status_t	DMIC_TransferReceiveDMA (DMIC_Type *base, dmic_dma_handle_t *handle, dmic_transfer_t *xfer, uint32_t dmic_channel)
	Receives data using DMA. More...
void	DMIC_TransferAbortReceiveDMA (DMIC_Type *base, dmic_dma_handle_t *handle)
	Aborts the received data using DMA. More...
status_t	DMIC_TransferGetReceiveCountDMA (DMIC_Type *base, dmic_dma_handle_t *handle, uint32_t *count)
	Get the number of bytes that have been received. More...
void	DMIC_InstallDMADescriptorMemory (dmic_dma_handle_t *handle, void *linkAddr, size_t linkNum)
	Install DMA descriptor memory. More...

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Data Structure Documentation

struct dmic_transfer_t

Data Fields
void *	data
	The buffer of data to be transfer. More...
uint8_t	dataWidth
	DMIC support 16bit/32bit.
size_t	dataSize
	The byte count to be transfer. More...
uint8_t	dataAddrInterleaveSize
	destination address interleave size
struct _dmic_transfer *	linkTransfer
	use to support link transfer

Field Documentation

void* dmic_transfer_t::data

size_t dmic_transfer_t::dataSize

struct _dmic_dma_handle

Data Fields
DMIC_Type *	base
	DMIC peripheral base address. More...
dma_handle_t *	rxDmaHandle
	The DMA RX channel used. More...
dmic_dma_transfer_callback_t	callback
	Callback function. More...
void *	userData
	DMIC callback function parameter. More...
size_t	transferSize
	Size of the data to receive. More...
volatile uint8_t	state
	Internal state of DMIC DMA transfer.
dma_descriptor_t *	desLink
	descriptor pool pointer
size_t	linkNum
	number of descriptor in descriptors pool

Field Documentation

DMIC_Type* dmic_dma_handle_t::base

dma_handle_t* dmic_dma_handle_t::rxDmaHandle

dmic_dma_transfer_callback_t dmic_dma_handle_t::callback

void* dmic_dma_handle_t::userData

size_t dmic_dma_handle_t::transferSize

Typedef Documentation

typedef void(* dmic_dma_transfer_callback_t)(DMIC_Type *base, dmic_dma_handle_t *handle, status_t status, void *userData)

Function Documentation

status_t DMIC_TransferCreateHandleDMA	(	DMIC_Type *	base,
		dmic_dma_handle_t *	handle,
		dmic_dma_transfer_callback_t	callback,
		void *	userData,
		dma_handle_t *	rxDmaHandle
	)

Parameters

base	DMIC peripheral base address.
handle	Pointer to dmic_dma_handle_t structure.
callback	Callback function.
userData	User data.
rxDmaHandle	User-requested DMA handle for RX DMA transfer.

status_t DMIC_TransferReceiveDMA	(	DMIC_Type *	base,
		dmic_dma_handle_t *	handle,
		dmic_transfer_t *	xfer,
		uint32_t	dmic_channel
	)

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

Parameters

base	USART peripheral base address.
handle	Pointer to usart_dma_handle_t structure.
xfer	DMIC DMA transfer structure. See dmic_transfer_t.
dmic_channel	DMIC start channel number.

Return values

kStatus_Success

void DMIC_TransferAbortReceiveDMA	(	DMIC_Type *	base,
		dmic_dma_handle_t *	handle
	)

This function aborts the received data using DMA.

Parameters

base	DMIC peripheral base address
handle	Pointer to dmic_dma_handle_t structure

status_t DMIC_TransferGetReceiveCountDMA	(	DMIC_Type *	base,
		dmic_dma_handle_t *	handle,
		uint32_t *	count
	)

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

Parameters

base	DMIC peripheral base address.
handle	DMIC 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;

void DMIC_InstallDMADescriptorMemory	(	dmic_dma_handle_t *	handle,
		void *	linkAddr,
		size_t	linkNum
	)

This function used to register DMA descriptor memory for linked transfer, a typical case is ping pong transfer which will request more than one DMA descriptor memory space, it should be called after DMIC_TransferCreateHandleDMA. User should be take care about the address of DMA descriptor pool which required align with 16BYTE at least.

Parameters

handle	Pointer to DMA channel transfer handle.
linkAddr	DMA link descriptor address.
num	DMA link descriptor number.