path: root/c/src/lib/libbsp/arm/atsam/libraries/libchip/source/usart_dma.c

/* ---------------------------------------------------------------------------- */
/*                  Atmel Microcontroller Software Support                      */
/*                       SAM Software Package License                           */
/* ---------------------------------------------------------------------------- */
/* Copyright (c) 2015, Atmel Corporation                                        */
/*                                                                              */
/* All rights reserved.                                                         */
/*                                                                              */
/* Redistribution and use in source and binary forms, with or without           */
/* modification, are permitted provided that the following condition is met:    */
/*                                                                              */
/* - Redistributions of source code must retain the above copyright notice,     */
/* this list of conditions and the disclaimer below.                            */
/*                                                                              */
/* Atmel's name may not be used to endorse or promote products derived from     */
/* this software without specific prior written permission.                     */
/*                                                                              */
/* DISCLAIMER:  THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR   */
/* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE   */
/* DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR ANY DIRECT, INDIRECT,      */
/* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT */
/* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,  */
/* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF    */
/* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING         */
/* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, */
/* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.                           */
/* ---------------------------------------------------------------------------- */

/**
* \addtogroup usart_dma_module USART xDMA driver
* \section Usage
*
* <ul>
* <li> USARTD_Configure() initializes and configures the USART peripheral
* and xDMA for data transfer.</li>
* <li> Configures the parameters for the device corresponding to the cs
* value by USARTD_ConfigureCS(). </li>
* </ul>
*
*/

/**
 * \file
 *
 * Implementation for the USART with xDMA driver.
 *
 */

/*----------------------------------------------------------------------------
 *        Headers
 *----------------------------------------------------------------------------*/

#include "chip.h"
#include "string.h"
#include "stdlib.h"

/*----------------------------------------------------------------------------
 *        Local functions
 *----------------------------------------------------------------------------*/

/**
 * \brief USART xDMA Rx callback
 * Invoked on USART DMA reception done.
 * \param channel DMA channel.
 * \param pArg Pointer to callback argument - Pointer to USARTDma instance.
 */
static void USARTD_Rx_Cb(uint32_t channel, UsartDma *pArg)
{

	UsartChannel *pUsartdCh = pArg->pRxChannel;

	if (channel != pUsartdCh->ChNum)
		return;

	/* Release the DMA channels */
	XDMAD_FreeChannel(pArg->pXdmad, pUsartdCh->ChNum);
	pUsartdCh->dmaProgress = 1;
	SCB_InvalidateDCache_by_Addr((uint32_t *)pUsartdCh->pBuff, pUsartdCh->BuffSize);

}

/**
 * \brief USART xDMA Rx callback
 * Invoked on USART DMA reception done.
 * \param channel DMA channel.
 * \param pArg Pointer to callback argument - Pointer to USARTDma instance.
 */
static void USARTD_Tx_Cb(uint32_t channel, UsartDma *pArg)
{
	UsartChannel *pUsartdCh = pArg->pTxChannel;

	if (channel != pUsartdCh->ChNum)
		return;

	/* Release the DMA channels */
	XDMAD_FreeChannel(pArg->pXdmad, pUsartdCh->ChNum);

	pUsartdCh->dmaProgress = 1;
}

/**
 * \brief Configure the USART Rx DMA Destination with Linker List mode.
 *
 * \param UsartChannel Pointer to USART dma channel
 * \returns 0 if the dma multibuffer configuration successfully; otherwise
 * returnsUSARTD_ERROR_XXX.
 */
static uint8_t _configureRxDma(UsartDma *pUsart, UsartChannel *pUsartRx)
{
	sXdmadCfg xdmadRxCfg;
	uint32_t xdmaCndc, xdmaInt;
	uint32_t i, LLI_Size;
	Usart *pUsartHwRx = pUsart->pUsartHw;
	sXdmad *pXdmadRx = pUsart->pXdmad;
	uint8_t *pBuff = 0;


	/* Setup RX Single block */
	if (pUsartRx->dmaProgrammingMode < XDMAD_LLI) {
		xdmadRxCfg.mbr_ubc = pUsartRx->BuffSize;
		xdmadRxCfg.mbr_da = (uint32_t)pUsartRx->pBuff;

		xdmadRxCfg.mbr_sa = (uint32_t)&pUsartHwRx->US_RHR;
		xdmadRxCfg.mbr_cfg = XDMAC_CC_TYPE_PER_TRAN |
							 XDMAC_CC_MBSIZE_SIXTEEN |
							 XDMAC_CC_DSYNC_PER2MEM |
							 XDMAC_CC_CSIZE_CHK_1 |
							 XDMAC_CC_DWIDTH_BYTE |
							 XDMAC_CC_SIF_AHB_IF1 |
							 XDMAC_CC_DIF_AHB_IF1 |
							 XDMAC_CC_SAM_FIXED_AM |
							 XDMAC_CC_DAM_INCREMENTED_AM |
							 XDMAC_CC_PERID(XDMAIF_Get_ChannelNumber
											(pUsart->usartId, XDMAD_TRANSFER_RX));

		xdmadRxCfg.mbr_bc = 0;

		if (pUsartRx->dmaProgrammingMode == XDMAD_MULTI)
			xdmadRxCfg.mbr_bc = pUsartRx->dmaBlockSize;

		xdmadRxCfg.mbr_sus = 0;
		xdmadRxCfg.mbr_dus = 0;
		xdmaCndc = 0;
		xdmaInt =  (XDMAC_CIE_BIE   |
					XDMAC_CIE_DIE   |
					XDMAC_CIE_FIE   |
					XDMAC_CIE_RBIE  |
					XDMAC_CIE_WBIE  |
					XDMAC_CIE_ROIE);
	} else if (pUsartRx->dmaProgrammingMode == XDMAD_LLI) {

		/* Setup RX Link List */
		LLI_Size = pUsartRx->dmaBlockSize;
		pBuff = pUsartRx->pBuff;

		if (pUsartRx->pLLIview != NULL) {
			free(pUsartRx->pLLIview);
			pUsartRx->pLLIview = NULL;
		}

		pUsartRx->pLLIview = malloc(sizeof(LinkedListDescriporView1) * LLI_Size);

		if (pUsartRx->pLLIview == NULL) {
			TRACE_ERROR(" Can not allocate memory to Rx LLI");
			return USARTD_ERROR;
		}

		xdmadRxCfg.mbr_cfg = XDMAC_CC_TYPE_PER_TRAN |
							 XDMAC_CC_MBSIZE_SIXTEEN |
							 XDMAC_CC_DSYNC_PER2MEM |
							 XDMAC_CC_MEMSET_NORMAL_MODE |
							 XDMAC_CC_CSIZE_CHK_1 |
							 XDMAC_CC_DWIDTH_BYTE |
							 XDMAC_CC_SIF_AHB_IF1 |
							 XDMAC_CC_DIF_AHB_IF1 |
							 XDMAC_CC_SAM_FIXED_AM |
							 XDMAC_CC_DAM_INCREMENTED_AM |
							 XDMAC_CC_PERID(XDMAIF_Get_ChannelNumber
											(pUsart->usartId, XDMAD_TRANSFER_RX));
		xdmadRxCfg.mbr_bc = 0;

		for (i = 0; i < LLI_Size; i++) {
			pUsartRx->pLLIview[i].mbr_ubc = XDMA_UBC_NVIEW_NDV1 |
											XDMA_UBC_NSEN_UNCHANGED |
											XDMA_UBC_NDEN_UPDATED |
											((i == LLI_Size - 1) ? (
												 (pUsartRx->dmaRingBuffer) ?
												 XDMA_UBC_NDE_FETCH_EN : 0) :
											 XDMA_UBC_NDE_FETCH_EN) |
											pUsartRx->BuffSize;
			pUsartRx->pLLIview[i].mbr_sa = (uint32_t)&pUsartHwRx->US_RHR;
			pUsartRx->pLLIview[i].mbr_da = (uint32_t)pBuff;
			pUsartRx->pLLIview[i].mbr_nda = (i == (LLI_Size - 1)) ?
											((pUsartRx->dmaRingBuffer) ? (uint32_t)pUsartRx->pLLIview : 0)
											: (uint32_t)&pUsartRx->pLLIview[ i + 1 ];
			pBuff += pUsartRx->BuffSize;
		}

		SCB_CleanDCache_by_Addr((uint32_t *)(pUsartRx->pLLIview),
								sizeof(LinkedListDescriporView1)*LLI_Size);
		xdmaCndc = XDMAC_CNDC_NDVIEW_NDV1 |
				   XDMAC_CNDC_NDE_DSCR_FETCH_EN |
				   XDMAC_CNDC_NDSUP_SRC_PARAMS_UPDATED |
				   XDMAC_CNDC_NDDUP_DST_PARAMS_UPDATED;
		xdmaInt = ((pUsartRx->dmaRingBuffer) ? XDMAC_CIE_BIE : XDMAC_CIE_LIE);
	} else
		return 1;

	if (XDMAD_ConfigureTransfer(
			pXdmadRx, pUsartRx->ChNum, &xdmadRxCfg, xdmaCndc,
			(uint32_t)pUsartRx->pLLIview, xdmaInt))
		return USARTD_ERROR;

	return 0;
}

/**
 * \brief Configure the USART tx DMA source with Linker List mode.
 *
 * \param UsartChannel Pointer to USART dma channel
  * \returns 0 if the dma multibuffer configuration successfully; otherwise returns
 * USARTD_ERROR_XXX.
 */
static uint8_t _configureTxDma(UsartDma *pUsart, UsartChannel *pUsartTx)
{
	sXdmadCfg xdmadTxCfg;
	uint32_t xdmaCndc, xdmaInt, LLI_Size, i;
	uint8_t *pBuff = 0;
	Usart *pUsartHwTx = pUsart->pUsartHw;
	sXdmad *pXdmadTx = pUsart->pXdmad;

	/* Setup TX Link List */

	if (pUsartTx->dmaProgrammingMode < XDMAD_LLI) {
		/* Number of Data */
		xdmadTxCfg.mbr_ubc =   pUsartTx->BuffSize;
		/* Source and Destination address of DMA */
		xdmadTxCfg.mbr_sa = (uint32_t)pUsartTx->pBuff;
		xdmadTxCfg.mbr_da = (uint32_t)&pUsartHwTx->US_THR;
		/* DMA Channel configuration */
		xdmadTxCfg.mbr_cfg = XDMAC_CC_TYPE_PER_TRAN |
							 XDMAC_CC_MBSIZE_SIXTEEN |
							 XDMAC_CC_DSYNC_MEM2PER |
							 XDMAC_CC_CSIZE_CHK_1 |
							 XDMAC_CC_DWIDTH_BYTE |
							 XDMAC_CC_SIF_AHB_IF1 |
							 XDMAC_CC_DIF_AHB_IF1 |
							 XDMAC_CC_SAM_INCREMENTED_AM |
							 XDMAC_CC_DAM_FIXED_AM |
							 XDMAC_CC_PERID(XDMAIF_Get_ChannelNumber
											(pUsart->usartId, XDMAD_TRANSFER_TX));

		xdmadTxCfg.mbr_bc = 0;

		if (pUsartTx->dmaProgrammingMode == XDMAD_MULTI)
			xdmadTxCfg.mbr_bc = pUsartTx->dmaBlockSize;

		xdmadTxCfg.mbr_sus = 0;
		xdmadTxCfg.mbr_dus = 0;
		xdmadTxCfg.mbr_ds = 0;
		xdmaCndc = 0;
		/* Enable End of Block; Read Bus error;  Write Bus Error;
		Overflow Error interrupt */
		xdmaInt =  (XDMAC_CIE_BIE    |
					XDMAC_CIE_RBIE  |
					XDMAC_CIE_WBIE  |
					XDMAC_CIE_ROIE);
	} else if (pUsartTx->dmaProgrammingMode == XDMAD_LLI) {
		LLI_Size = pUsartTx->dmaBlockSize;
		pBuff = pUsartTx->pBuff;

		/* If channel's LLI is already configured and application
		want to reconfigured it, free before re-allocating memory */
		if (pUsartTx->pLLIview != NULL) {
			free(pUsartTx->pLLIview);
			pUsartTx->pLLIview = NULL;
		}

		pUsartTx->pLLIview = malloc(sizeof(LinkedListDescriporView1) * LLI_Size);

		if (pUsartTx->pLLIview == NULL) {
			TRACE_ERROR(" Can not allocate memory to Tx LLI");
			return USARTD_ERROR;
		}

		xdmadTxCfg.mbr_cfg = XDMAC_CC_TYPE_PER_TRAN |
							 XDMAC_CC_MBSIZE_SIXTEEN |
							 XDMAC_CC_DSYNC_MEM2PER |
							 XDMAC_CC_MEMSET_NORMAL_MODE |
							 XDMAC_CC_CSIZE_CHK_1 |
							 XDMAC_CC_DWIDTH_BYTE |
							 XDMAC_CC_SIF_AHB_IF1 |
							 XDMAC_CC_DIF_AHB_IF1 |
							 XDMAC_CC_SAM_INCREMENTED_AM |
							 XDMAC_CC_DAM_FIXED_AM |
							 XDMAC_CC_PERID(XDMAIF_Get_ChannelNumber
											(pUsart->usartId, XDMAD_TRANSFER_TX));
		xdmadTxCfg.mbr_bc = 0;

		for (i = 0; i < LLI_Size; i++) {
			pUsartTx->pLLIview[i].mbr_ubc = XDMA_UBC_NVIEW_NDV1 |
											XDMA_UBC_NSEN_UPDATED |
											XDMA_UBC_NDEN_UNCHANGED |
											((i == LLI_Size - 1) ? ((pUsartTx->dmaRingBuffer)
													? XDMA_UBC_NDE_FETCH_EN : 0) :
											 XDMA_UBC_NDE_FETCH_EN) | pUsartTx->BuffSize;
			pUsartTx->pLLIview[i].mbr_sa = (uint32_t)pBuff;
			pUsartTx->pLLIview[i].mbr_da = (uint32_t)&pUsartHwTx->US_THR;
			pUsartTx->pLLIview[i].mbr_nda = (i == (LLI_Size - 1)) ?
											((pUsartTx->dmaRingBuffer) ? (uint32_t)pUsartTx->pLLIview : 0)
											: (uint32_t)&pUsartTx->pLLIview[ i + 1 ];
			pBuff += pUsartTx->BuffSize;
		}

		SCB_CleanDCache_by_Addr((uint32_t *)(pUsartTx->pLLIview),
								sizeof(LinkedListDescriporView1)*LLI_Size);
		xdmaCndc = XDMAC_CNDC_NDVIEW_NDV1 |
				   XDMAC_CNDC_NDE_DSCR_FETCH_EN |
				   XDMAC_CNDC_NDSUP_SRC_PARAMS_UPDATED |
				   XDMAC_CNDC_NDDUP_DST_PARAMS_UPDATED;
		xdmaInt = ((pUsartTx->dmaRingBuffer) ? XDMAC_CIE_BIE : XDMAC_CIE_LIE);
	} else {
		TRACE_ERROR("DmaProgState is incorrect \n\r");
		return 1;
	}

	if (XDMAD_ConfigureTransfer(pXdmadTx, pUsartTx->ChNum,
								 &xdmadTxCfg, xdmaCndc, (uint32_t)pUsartTx->pLLIview, xdmaInt))
		return USARTD_ERROR;

	return 0;
}

/*----------------------------------------------------------------------------
 *        Exported functions
 *----------------------------------------------------------------------------*/
/**
 * \brief Initializes the USARTDma structure and the corresponding USART & DMA .
 * hardware select value.
 * The driver will uses DMA channel 0 for RX and DMA channel 1 for TX.
 * The DMA channels are freed automatically when no USART command processing.
 *
 * \param pUSARTD  Pointer to a UsartDma instance.
 * \param pUsartHw Associated USART peripheral.
 * \param usartId  USART peripheral identifier.
 * \param UsartClk USART clock.
 * \param pXdmad  Pointer to a Dmad instance.
 */
uint32_t USARTD_Configure(UsartDma *pUsartd ,
						   uint8_t usartId,
						   uint32_t UsartMode,
						   uint32_t BaudRate,
						   uint32_t UsartClk)
{
	/* Enable the peripheral clock in the PMC*/
	PMC_EnablePeripheral(usartId);

	/* Initialize the USART structure */
	pUsartd->usartId  = usartId;

	if (usartId == ID_USART0)
		pUsartd->pUsartHw = USART0;

	if (usartId == ID_USART1)
		pUsartd->pUsartHw = USART1;

	if (usartId == ID_USART2)
		pUsartd->pUsartHw = USART2;


	pUsartd->pXdmad->pXdmacs = XDMAC;
	/* Enable the USART Peripheral ,Execute a software reset of the USART,
	    Configure USART in Master Mode*/
	USART_Configure (pUsartd->pUsartHw, UsartMode, BaudRate, UsartClk);

	/* Driver initialize */
	XDMAD_Initialize(pUsartd->pXdmad, 0);

	/* Check if DMA IRQ is enable; if not clear pending IRQs in init it */
	if (!(NVIC_GetActive(XDMAC_IRQn)))
		NVIC_ClearPendingIRQ(XDMAC_IRQn);

	return 0;
}

/**
 * \brief This function initialize the appropriate DMA channel for Rx channel
 * of USART
 * \param pUsartd       Pointer to a UsartDma instance.
 * \param pRxCh         Pointer to TxChannel configuration
 * \returns             0 if the transfer has been started successfully;
 * otherwise returns USARTD_ERROR_LOCK is the driver is in use, or
 * USARTD_ERROR if the command is not valid.
 */
uint32_t USARTD_EnableRxChannels(UsartDma *pUsartd, UsartChannel *pRxCh)
{
	uint32_t Channel;

	assert(pRxCh);
	/* Init USART Rx Channel. */
	pUsartd->pRxChannel = pRxCh;

	/* Enables the USART to receive data. */
	USART_SetReceiverEnabled (pUsartd->pUsartHw , ENABLE);


	/* Allocate a DMA channel for USART0/1 RX. */
	Channel =  XDMAD_AllocateChannel(pUsartd->pXdmad, pUsartd->usartId,
									  XDMAD_TRANSFER_MEMORY);

	if (Channel == XDMAD_ALLOC_FAILED)
		return USARTD_ERROR;

	pRxCh->ChNum = Channel;

	/* Setup callbacks for USART RX */
	if (pUsartd->pRxChannel->callback) {
		XDMAD_SetCallback(pUsartd->pXdmad, pRxCh->ChNum,
						  (XdmadTransferCallback)pRxCh->callback, pRxCh->pArgument);
	} else {
		XDMAD_SetCallback(pUsartd->pXdmad, pRxCh->ChNum,
						  (XdmadTransferCallback)USARTD_Rx_Cb, pUsartd);
	}


	if (XDMAD_PrepareChannel(pUsartd->pXdmad, pRxCh->ChNum))
		return USARTD_ERROR;

	if (_configureRxDma(pUsartd , pUsartd->pRxChannel))
		return USARTD_ERROR_LOCK;

	/* Check if DMA IRQ is enable; if not Enable it */
	if (!(NVIC_GetActive(XDMAC_IRQn))) {
		/* Enable interrupt  */
		NVIC_EnableIRQ(XDMAC_IRQn);
	}

	return 0;
}

/**
 * \brief This function initialize the appropriate DMA channel for Tx channel
 * of USART
 * \param pUsartd       Pointer to a USARTDma instance.
 * \param pTxCh         Pointer to TxChannel configuration
 * \returns             0 if the transfer has been started successfully;
 * otherwise returns USARTD_ERROR_LOCK is the driver is in use, or
 * USARTD_ERROR if the command is not valid.
 */
uint32_t USARTD_EnableTxChannels(UsartDma *pUsartd, UsartChannel *pTxCh)
{

	uint32_t Channel;

	assert(pTxCh);

	/* Init USART Tx Channel. */
	pUsartd->pTxChannel = pTxCh;

	/* Enables the USART to transfer data. */
	USART_SetTransmitterEnabled (pUsartd->pUsartHw , ENABLE);

	/* Allocate a DMA channel for USART0/1 TX. */
	Channel =  XDMAD_AllocateChannel(pUsartd->pXdmad, XDMAD_TRANSFER_MEMORY,
									  pUsartd->usartId);

	if (Channel == XDMAD_ALLOC_FAILED)
		return USARTD_ERROR;

	pTxCh->ChNum = Channel;

	/* Setup callbacks for USART0/1 TX */
	if (pUsartd->pTxChannel->callback) {
		XDMAD_SetCallback(pUsartd->pXdmad, pTxCh->ChNum,
						  (XdmadTransferCallback)pTxCh->callback, pTxCh->pArgument);
	} else
		XDMAD_SetCallback(pUsartd->pXdmad, pTxCh->ChNum,
						  (XdmadTransferCallback)USARTD_Tx_Cb, pUsartd);

	if (XDMAD_PrepareChannel(pUsartd->pXdmad, pTxCh->ChNum))
		return USARTD_ERROR;

	if (_configureTxDma(pUsartd , pUsartd->pTxChannel))
		return USARTD_ERROR_LOCK;

	/* Check if DMA IRQ is enable; if not Enable it */
	if (!(NVIC_GetActive(XDMAC_IRQn))) {
		/* Enable interrupt  */
		NVIC_EnableIRQ(XDMAC_IRQn);
	}

	return 0;
}

/**
 * \brief This function disables the appropriate DMA channel for Rx channel of
 * USART
 * \param pUsartd       Pointer to a UsartDma instance.
 * \param pRxCh         Pointer to TxChannel configuration
 * \returns             0 if the transfer has been started successfully;
 * otherwise returns USARTD_ERROR_LOCK is the driver is in use, or
 * USARTD_ERROR if the command is not valid.
 */
uint32_t USARTD_DisableRxChannels(UsartDma *pUsartd, UsartChannel *pRxCh)
{
	assert(pRxCh);

	/* Enables the USART to transfer data. */
	USART_SetReceiverEnabled (pUsartd->pUsartHw , DISABLE);

	XDMAD_StopTransfer(pUsartd->pXdmad, pRxCh->ChNum);

	XDMAD_SetCallback(pUsartd->pXdmad, pRxCh->ChNum, NULL, NULL);

	/* Free allocated DMA channel for USART TX. */
	if (XDMAD_FreeChannel(pUsartd->pXdmad, pRxCh->ChNum) != XDMAD_OK)
		return USARTD_ERROR;

	if (pRxCh->dmaProgrammingMode == XDMAD_LLI) {
		free(pRxCh->pLLIview);
		pRxCh->pLLIview = NULL;
	}

	pRxCh->dmaProgress = 1;
	return 0;
}

/**
 * \brief This function disables the appropriate DMA channel for Tx channel of
 * USART
 * \param pUsartd       Pointer to a USARTDma instance.
 * \param pTxCh         Pointer to TxChannel configuration
 * \returns             0 if the transfer has been started successfully;
 * otherwise returns USARTD_ERROR_LOCK is the driver is in use, or
 * USARTD_ERROR if the command is not valid.
 */

uint32_t USARTD_DisableTxChannels(UsartDma *pUsartd, UsartChannel *pTxCh)
{
	assert(pTxCh);

	/* Enables the USART to transfer data. */
	USART_SetTransmitterEnabled (pUsartd->pUsartHw , DISABLE);

	XDMAD_StopTransfer(pUsartd->pXdmad, pTxCh->ChNum);

	XDMAD_SetCallback(pUsartd->pXdmad, pTxCh->ChNum, NULL, NULL);

	/* Free allocated DMA channel for USART TX. */
	if (XDMAD_FreeChannel(pUsartd->pXdmad, pTxCh->ChNum) != XDMAD_OK)
		return USARTD_ERROR;

	if (pTxCh->dmaProgrammingMode == XDMAD_LLI) {
		free(pTxCh->pLLIview);
		pTxCh->pLLIview = NULL;
	}

	pTxCh->dmaProgress = 1;
	return 0;
}

/**
 * \brief Starts a USART master transfer. This is a non blocking function. It
 * will return as soon as the transfer is started.
 *
 * \param pUSARTD  Pointer to a USARTDma instance.
 * \returns 0 if the transfer has been started successfully; otherwise returns
 * USARTD_ERROR_LOCK is the driver is in use, or USARTD_ERROR if the command is
 * not valid.
 */
uint32_t USARTD_SendData(UsartDma *pUsartd)
{
	/* Start DMA 0(RX) && 1(TX) */
	pUsartd->pTxChannel->dmaProgress = 0;
	SCB_CleanDCache_by_Addr((uint32_t *)pUsartd->pTxChannel->pBuff,
							pUsartd->pTxChannel->BuffSize);

	if (XDMAD_StartTransfer(pUsartd->pXdmad, pUsartd->pTxChannel->ChNum))
		return USARTD_ERROR_LOCK;

	return 0;
}

/**
 * \brief Starts a USART master transfer. This is a non blocking function. It will
 *  return as soon as the transfer is started.
 *
 * \param pUSARTD  Pointer to a USARTDma instance.
 * \returns 0 if the transfer has been started successfully; otherwise returns
 * USARTD_ERROR_LOCK is the driver is in use, or USARTD_ERROR if the command is not
 * valid.
 */
uint32_t USARTD_RcvData(UsartDma *pUsartd)
{
	/* Start DMA 0(RX) && 1(TX) */
	pUsartd->pRxChannel->dmaProgress = 0;

	if (XDMAD_StartTransfer(pUsartd->pXdmad, pUsartd->pRxChannel->ChNum))
		return USARTD_ERROR_LOCK;

	return 0;
}