PDM EDMA Driver

Data Structures
struct	_pdm_edma_transfer
	PDM edma transfer. More...
struct	_pdm_edma_handle
	PDM DMA transfer handle, users should not touch the content of the handle. More...

Driver version
enum	_pdm_edma_multi_channel_interleave { kPDM_EDMAMultiChannelInterleavePerChannelSample , kPDM_EDMAMultiChannelInterleavePerChannelBlock }
	pdm multi channel interleave type More...
typedef struct _pdm_edma_handle	pdm_edma_handle_t
	PDM edma handler.
typedef enum _pdm_edma_multi_channel_interleave	pdm_edma_multi_channel_interleave_t
	pdm multi channel interleave type
typedef struct _pdm_edma_transfer	pdm_edma_transfer_t
	PDM edma transfer.
typedef void(*	pdm_edma_callback_t) (PDM_Type *base, pdm_edma_handle_t *handle, status_t status, void *userData)
	PDM eDMA transfer callback function for finish and error.
#define	FSL_PDM_EDMA_DRIVER_VERSION   (MAKE_VERSION(2, 6, 1))

PDM eDMA Transactional
void	PDM_TransferInstallEDMATCDMemory (pdm_edma_handle_t *handle, void *tcdAddr, size_t tcdNum)
	Install EDMA descriptor memory.
void	PDM_TransferCreateHandleEDMA (PDM_Type *base, pdm_edma_handle_t *handle, pdm_edma_callback_t callback, void *userData, edma_handle_t *dmaHandle)
	Initializes the PDM Rx eDMA handle.
void	PDM_TransferSetMultiChannelInterleaveType (pdm_edma_handle_t *handle, pdm_edma_multi_channel_interleave_t multiChannelInterleaveType)
	Initializes the multi PDM channel interleave type.
void	PDM_TransferSetChannelConfigEDMA (PDM_Type *base, pdm_edma_handle_t *handle, uint32_t channel, const pdm_channel_config_t *config)
	Configures the PDM channel.
status_t	PDM_TransferReceiveEDMA (PDM_Type *base, pdm_edma_handle_t *handle, pdm_edma_transfer_t *xfer)
	Performs a non-blocking PDM receive using eDMA.
void	PDM_TransferTerminateReceiveEDMA (PDM_Type *base, pdm_edma_handle_t *handle)
	Terminate all PDM receive.
void	PDM_TransferAbortReceiveEDMA (PDM_Type *base, pdm_edma_handle_t *handle)
	Aborts a PDM receive using eDMA.
status_t	PDM_TransferGetReceiveCountEDMA (PDM_Type *base, pdm_edma_handle_t *handle, size_t *count)
	Gets byte count received by PDM.

Detailed Description

Macro Definition Documentation

FSL_PDM_EDMA_DRIVER_VERSION

#define FSL_PDM_EDMA_DRIVER_VERSION   (MAKE_VERSION(2, 6, 1))

Version 2.6.1

Enumeration Type Documentation

_pdm_edma_multi_channel_interleave

enum _pdm_edma_multi_channel_interleave

pdm multi channel interleave type

Enumerator
kPDM_EDMAMultiChannelInterleavePerChannelSample	multi channel PDM data interleave per channel sample |CHANNEL0 | CHANNEL1 | CHANNEL0 | CHANNEL1 | CHANNEL0 | CHANNEL 1 | ....|
kPDM_EDMAMultiChannelInterleavePerChannelBlock	multi channel PDM data interleave per channel block |CHANNEL0 | CHANNEL0 | CHANNEL0 | ...... | CHANNEL1 | CHANNEL 1 | CHANNEL 1 | ....| CHANNEL2 | CHANNEL 2 | CHANNEL 2 | ....|

Function Documentation

PDM_TransferAbortReceiveEDMA()

void PDM_TransferAbortReceiveEDMA	(	PDM_Type *	base,
		pdm_edma_handle_t *	handle
	)

Aborts a PDM receive using eDMA.

This function only aborts the current transfer slots, the other transfer slots' information still kept in the handler. If users want to terminate all transfer slots, just call PDM_TransferTerminateReceiveEDMA.

Parameters

base	PDM base pointer
handle	PDM eDMA handle pointer.

brief Aborts a PDM receive using eDMA.

This function only aborts the current transfer slots, the other transfer slots' information still kept in the handler. If users want to terminate all transfer slots, just call PDM_TransferTerminateReceiveEDMA.

param base PDM base pointer param handle PDM eDMA handle pointer.

PDM_TransferCreateHandleEDMA()

void PDM_TransferCreateHandleEDMA	(	PDM_Type *	base,
		pdm_edma_handle_t *	handle,
		pdm_edma_callback_t	callback,
		void *	userData,
		edma_handle_t *	dmaHandle
	)

Initializes the PDM Rx eDMA handle.

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

Parameters

base	PDM base pointer.
handle	PDM eDMA handle pointer.
callback	Pointer to user callback function.
userData	User parameter passed to the callback function.
dmaHandle	eDMA handle pointer, this handle shall be static allocated by users.

brief Initializes the PDM Rx eDMA handle.

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

param base PDM base pointer. param handle PDM eDMA handle pointer. param base PDM peripheral base address. param callback Pointer to user callback function. param userData User parameter passed to the callback function. param dmaHandle eDMA handle pointer, this handle shall be static allocated by users.

PDM_TransferGetReceiveCountEDMA()

status_t PDM_TransferGetReceiveCountEDMA	(	PDM_Type *	base,
		pdm_edma_handle_t *	handle,
		size_t *	count
	)

Gets byte count received by PDM.

Parameters

base	PDM base pointer
handle	PDM eDMA handle pointer.
count	Bytes count received by PDM.

Return values

kStatus_Success	Succeed get the transfer count.
kStatus_NoTransferInProgress	There is no non-blocking transaction in progress.

brief Gets byte count received by PDM.

param base PDM base pointer param handle PDM eDMA handle pointer. param count Bytes count received by PDM. retval kStatus_Success Succeed get the transfer count. retval kStatus_NoTransferInProgress There is no non-blocking transaction in progress.

PDM_TransferInstallEDMATCDMemory()

void PDM_TransferInstallEDMATCDMemory	(	pdm_edma_handle_t *	handle,
		void *	tcdAddr,
		size_t	tcdNum
	)

Install EDMA descriptor memory.

Parameters

handle	Pointer to EDMA channel transfer handle.
tcdAddr	EDMA head descriptor address.
tcdNum	EDMA link descriptor address.

brief Install EDMA descriptor memory.

param handle Pointer to EDMA channel transfer handle. param tcdAddr EDMA head descriptor address. param tcdNum EDMA link descriptor address.

PDM_TransferReceiveEDMA()

status_t PDM_TransferReceiveEDMA	(	PDM_Type *	base,
		pdm_edma_handle_t *	handle,
		pdm_edma_transfer_t *	xfer
	)

Performs a non-blocking PDM receive using eDMA.

Note

This interface returns immediately after the transfer initiates. Call the PDM_GetReceiveRemainingBytes to poll the transfer status and check whether the PDM transfer is finished.

1. Scatter gather case: This functio support dynamic scatter gather and staic scatter gather, a. for the dynamic scatter gather case: Application should call PDM_TransferReceiveEDMA function continuously to make sure new receive request is submit before the previous one finish. b. for the static scatter gather case: Application should use the link transfer feature and make sure a loop link transfer is provided, such as:

   pdm_edma_transfer_t pdmXfer[2] =
    {
        {
        .data  = s_buffer,
        .dataSize = BUFFER_SIZE,
        .linkTransfer = &pdmXfer[1],
        },
    
        {
        .data  = &s_buffer[BUFFER_SIZE],
        .dataSize = BUFFER_SIZE,
        .linkTransfer = &pdmXfer[0]
        },
    };

2. Multi channel case: This function support receive multi pdm channel data, for example, if two channel is requested,

   PDM_TransferSetChannelConfigEDMA(DEMO_PDM, &s_pdmRxHandle_0, DEMO_PDM_ENABLE_CHANNEL_0, &channelConfig);
   PDM_TransferSetChannelConfigEDMA(DEMO_PDM, &s_pdmRxHandle_0, DEMO_PDM_ENABLE_CHANNEL_1, &channelConfig);
   PDM_TransferReceiveEDMA(DEMO_PDM, &s_pdmRxHandle_0, pdmXfer);

   The output data will be formatted as below if handle->interleaveType =

   kPDM_EDMAMultiChannelInterleavePerChannelSample :

|CHANNEL0 | CHANNEL1 | CHANNEL0 | CHANNEL1 | CHANNEL0 | CHANNEL 1 | ....|

The output data will be formatted as below if handle->interleaveType = kPDM_EDMAMultiChannelInterleavePerChannelBlock

:

|CHANNEL3 | CHANNEL3 | CHANNEL3 | .... | CHANNEL4 | CHANNEL 4 | CHANNEL4 |....| CHANNEL5 | CHANNEL 5 | CHANNEL5

|....|

Note: the dataSize of xfer is the total data size, while application using kPDM_EDMAMultiChannelInterleavePerChannelBlock, the buffer size for each PDM channel is channelSize = dataSize / channelNums, then there are limitation for this feature,

1. 3 DMIC array: the dataSize shall be 4 * (channelSize) The addtional buffer is mandantory for edma modulo feature.
2. The kPDM_EDMAMultiChannelInterleavePerChannelBlock feature support below dmic array only, 2 DMIC array: CHANNEL3, CHANNEL4 3 DMIC array: CHANNEL3, CHANNEL4, CHANNEL5 4 DMIC array: CHANNEL3, CHANNEL4, CHANNEL5, CHANNEL6 Any other combinations is not support, that is to SAY, THE FEATURE SUPPORT RECEIVE START FROM CHANNEL3 ONLY AND 4 MAXIMUM DMIC CHANNELS.

Parameters

base	PDM base pointer
handle	PDM eDMA handle pointer.
xfer	Pointer to DMA transfer structure.

Return values

kStatus_Success	Start a PDM eDMA receive successfully.
kStatus_InvalidArgument	The input argument is invalid.
kStatus_RxBusy	PDM is busy receiving data.

brief Performs a non-blocking PDM receive using eDMA.

note This interface returns immediately after the transfer initiates. Call the PDM_GetReceiveRemainingBytes to poll the transfer status and check whether the PDM transfer is finished.

1. Scatter gather case: This functio support dynamic scatter gather and staic scatter gather, a. for the dynamic scatter gather case: Application should call PDM_TransferReceiveEDMA function continuously to make sure new receive request is submit before the previous one finish. b. for the static scatter gather case: Application should use the link transfer feature and make sure a loop link transfer is provided, such as: code pdm_edma_transfer_t pdmXfer[2] = { { .data = s_buffer, .dataSize = BUFFER_SIZE, .linkTransfer = &pdmXfer[1], },

   { .data = &s_buffer[BUFFER_SIZE], .dataSize = BUFFER_SIZE, .linkTransfer = &pdmXfer[0] }, }; endcode

2. Multi channel case: This function support receive multi pdm channel data, for example, if two channel is requested, code PDM_TransferSetChannelConfigEDMA(DEMO_PDM, &s_pdmRxHandle_0, DEMO_PDM_ENABLE_CHANNEL_0, &channelConfig); PDM_TransferSetChannelConfigEDMA(DEMO_PDM, &s_pdmRxHandle_0, DEMO_PDM_ENABLE_CHANNEL_1, &channelConfig); PDM_TransferReceiveEDMA(DEMO_PDM, &s_pdmRxHandle_0, pdmXfer); endcode The output data will be formatted as below if handle->interleaveType =

   kPDM_EDMAMultiChannelInterleavePerChannelSample :

|CHANNEL0 | CHANNEL1 | CHANNEL0 | CHANNEL1 | CHANNEL0 | CHANNEL 1 | ....|

The output data will be formatted as below if handle->interleaveType = kPDM_EDMAMultiChannelInterleavePerChannelBlock

:

|CHANNEL3 | CHANNEL3 | CHANNEL3 | .... | CHANNEL4 | CHANNEL 4 | CHANNEL4 |....| CHANNEL5 | CHANNEL 5 | CHANNEL5

|....|

Note: the dataSize of xfer is the total data size, while application using kPDM_EDMAMultiChannelInterleavePerChannelBlock, the buffer size for each PDM channel is channelSize = dataSize / channelNums, there are limitation for this feature,

1. For 3 DMIC array: the dataSize shall be 4 * (channelSize) The addtional buffer is mandantory for edma modulo feature.
2. The kPDM_EDMAMultiChannelInterleavePerChannelBlock feature support below dmic array only, 2 DMIC array: CHANNEL3, CHANNEL4 3 DMIC array: CHANNEL3, CHANNEL4, CHANNEL5 4 DMIC array: CHANNEL3, CHANNEL4, CHANNEL5, CHANNEL6 Any other combinations is not support, that is to SAY, THE FEATURE SUPPORT RECEIVE START FROM CHANNEL3 ONLY AND 4 MAXIMUM DMIC CHANNELS.

param base PDM base pointer param handle PDM eDMA handle pointer. param xfer Pointer to DMA transfer structure. retval kStatus_Success Start a PDM eDMA receive successfully. retval kStatus_InvalidArgument The input argument is invalid. retval kStatus_RxBusy PDM is busy receiving data.

PDM_TransferSetChannelConfigEDMA()

void PDM_TransferSetChannelConfigEDMA	(	PDM_Type *	base,
		pdm_edma_handle_t *	handle,
		uint32_t	channel,
		const pdm_channel_config_t *	config
	)

Configures the PDM channel.

Parameters

base	PDM base pointer.
handle	PDM eDMA handle pointer.
channel	channel index.
config	pdm channel configurations.

brief Configures the PDM channel.

param base PDM base pointer. param handle PDM eDMA handle pointer. param channel channel index. param pdmConfig pdm channel configurations.

PDM_TransferSetMultiChannelInterleaveType()

void PDM_TransferSetMultiChannelInterleaveType	(	pdm_edma_handle_t *	handle,
		pdm_edma_multi_channel_interleave_t	multiChannelInterleaveType
	)

Initializes the multi PDM channel interleave type.

This function initializes the PDM DMA handle member interleaveType, it shall be called only when application would like to use type kPDM_EDMAMultiChannelInterleavePerChannelBlock, since the default interleaveType is kPDM_EDMAMultiChannelInterleavePerChannelSample always

Parameters

handle	PDM eDMA handle pointer.
multiChannelInterleaveType	Multi channel interleave type.

brief Initializes the multi PDM channel interleave type.

This function initializes the PDM DMA handle member interleaveType, it shall be called only when application would like to use type kPDM_EDMAMultiChannelInterleavePerChannelBlock, since the default interleaveType is kPDM_EDMAMultiChannelInterleavePerChannelSample always

param handle PDM eDMA handle pointer. param multiChannelInterleaveType Multi channel interleave type.

PDM_TransferTerminateReceiveEDMA()

void PDM_TransferTerminateReceiveEDMA	(	PDM_Type *	base,
		pdm_edma_handle_t *	handle
	)

Terminate all PDM receive.

This function will clear all transfer slots buffered in the pdm queue. If users only want to abort the current transfer slot, please call PDM_TransferAbortReceiveEDMA.

Parameters

base	PDM base pointer.
handle	PDM eDMA handle pointer.

brief Terminate all PDM receive.

This function will clear all transfer slots buffered in the pdm queue. If users only want to abort the current transfer slot, please call PDM_TransferAbortReceiveEDMA.

param base PDM base pointer. param handle PDM eDMA handle pointer.