SPI Callback doesn't work the second time

[usama2]

Posted on December 13, 2017 at 03:32

Hi,

I'm trying to implement SPI Tx and Rx with LL API. In stripped down code, I have these in my initialization function:

LL_SPI_EnableDMAReq_RX

LL_SPI_EnableDMAReq_TX

LL_DMA_ConfigTransfer(DmaInstanceT, DmaStreamT,LL_DMA_DIRECTION_MEMORY_TO_PERIPH | LL_DMA_PRIORITY_VERYHIGH | LL_DMA_MODE_NORMAL |

                        LL_DMA_PERIPH_NOINCREMENT | LL_DMA_MEMORY_INCREMENT | LL_DMA_PDATAALIGN_BYTE | LL_DMA_MDATAALIGN_BYTE);

  LL_DMA_ConfigTransfer(DmaInstanceR, DmaStreamR,LL_DMA_DIRECTION_PERIPH_TO_MEMORY | LL_DMA_PRIORITY_VERYHIGH | LL_DMA_MODE_NORMAL |

                        LL_DMA_PERIPH_NOINCREMENT | LL_DMA_MEMORY_INCREMENT | LL_DMA_PDATAALIGN_BYTE | LL_DMA_MDATAALIGN_BYTE);

  LL_DMA_EnableIT_TC(DmaInstanceR, DmaStreamR);

  LL_DMA_EnableIT_TE(DmaInstanceR, DmaStreamR);

  LL_SPI_Enable(hspi->Instance);

Then, for SPI Tx and Rx, I made another function which goes something like:

LL_DMA_ConfigAddresses(DmaInstanceT, DmaStreamT, (uint32_t)aTxBuffer, LL_SPI_DMA_GetRegAddr(hspi->Instance), LL_DMA_GetDataTransferDirection(DmaInstanceT, DmaStreamT));

LL_DMA_SetDataLength(DmaInstanceT, DmaStreamT, Size);

LL_DMA_ConfigAddresses(DmaInstanceR, DmaStreamR, LL_SPI_DMA_GetRegAddr(hspi->Instance), (uint32_t)aRxBuffer, LL_DMA_GetDataTransferDirection(DmaInstanceR, DmaStreamR));

LL_DMA_SetDataLength(DmaInstanceR, DmaStreamR, Size);

LL_DMA_EnableStream(DmaInstanceR, DmaStreamR);

LL_DMA_EnableStream(DmaInstanceT, DmaStreamT);

I set the callback

void DMA1_Stream3_IRQHandler(void)

{

  /* USER CODE BEGIN DMA1_Stream3_IRQn 0 */

HB_SPI_TxRxCpltCallback(&hdma_spi2_rx);

}

void HB_SPI_TxRxCpltCallback(DMA_HandleTypeDef *hdma)

{

  if(LL_DMA_IsActiveFlag_TC3(DMA1))

  {

    LL_DMA_ClearFlag_TC3(DMA1);

  }

  if(LL_DMA_IsActiveFlag_TE3(DMA1))

  {

    LL_DMA_ClearFlag_TE3(DMA1);

  }

SPI_HandleTypeDef* hspi = ( SPI_HandleTypeDef* )((DMA_HandleTypeDef* )hdma)->Parent;

DMA_TypeDef*  DmaInstanceT;

DMA_TypeDef*  DmaInstanceR;

uint32_t DmaStreamT;

uint32_t DmaStreamR;

DmaInstanceT        = __LL_DMA_GET_INSTANCE(hspi->hdmatx->Instance);

DmaStreamT          = __LL_DMA_GET_STREAM(hspi->hdmatx->Instance);

DmaInstanceR        = __LL_DMA_GET_INSTANCE(hspi->hdmarx->Instance);

DmaStreamR          = __LL_DMA_GET_STREAM(hspi->hdmarx->Instance);

/* Disable DMA2 Rx Channel */

LL_DMA_DisableStream(DmaInstanceR, DmaStreamR);

/* Disable DMA2 Tx Channel */

LL_DMA_DisableStream(DmaInstanceT, DmaStreamT);

  StartFrametransfer(); //This calls the SPI TxRx function

}

The problem is that this callback gets called only once. I can't figure out why.

#stm32-f4 #ll-drivers #callback #spi-write-and-read