stm32l4xx_hal_crc.c

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/* Includes ------------------------------------------------------------------*/
#include "stm32l4xx_hal.h"

#ifdef HAL_CRC_MODULE_ENABLED

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
static uint32_t CRC_Handle_8(CRC_HandleTypeDef *hcrc, uint8_t pBuffer[], uint32_t BufferLength);
static uint32_t CRC_Handle_16(CRC_HandleTypeDef *hcrc, uint16_t pBuffer[], uint32_t BufferLength);
/* Exported functions --------------------------------------------------------*/

HAL_StatusTypeDef HAL_CRC_Init(CRC_HandleTypeDef *hcrc)
{
  /* Check the CRC handle allocation */
  if (hcrc == NULL)
  {
    return HAL_ERROR;
  }

  /* Check the parameters */
  assert_param(IS_CRC_ALL_INSTANCE(hcrc->Instance));

  if (hcrc->State == HAL_CRC_STATE_RESET)
  {
    /* Allocate lock resource and initialize it */
    hcrc->Lock = HAL_UNLOCKED;
    /* Init the low level hardware */
    HAL_CRC_MspInit(hcrc);
  }

  hcrc->State = HAL_CRC_STATE_BUSY;

  /* check whether or not non-default generating polynomial has been
   * picked up by user */
  assert_param(IS_DEFAULT_POLYNOMIAL(hcrc->Init.DefaultPolynomialUse));
  if (hcrc->Init.DefaultPolynomialUse == DEFAULT_POLYNOMIAL_ENABLE)
  {
    /* initialize peripheral with default generating polynomial */
    WRITE_REG(hcrc->Instance->POL, DEFAULT_CRC32_POLY);
    MODIFY_REG(hcrc->Instance->CR, CRC_CR_POLYSIZE, CRC_POLYLENGTH_32B);
  }
  else
  {
    /* initialize CRC peripheral with generating polynomial defined by user */
    if (HAL_CRCEx_Polynomial_Set(hcrc, hcrc->Init.GeneratingPolynomial, hcrc->Init.CRCLength) != HAL_OK)
    {
      return HAL_ERROR;
    }
  }

  /* check whether or not non-default CRC initial value has been
   * picked up by user */
  assert_param(IS_DEFAULT_INIT_VALUE(hcrc->Init.DefaultInitValueUse));
  if (hcrc->Init.DefaultInitValueUse == DEFAULT_INIT_VALUE_ENABLE)
  {
    WRITE_REG(hcrc->Instance->INIT, DEFAULT_CRC_INITVALUE);
  }
  else
  {
    WRITE_REG(hcrc->Instance->INIT, hcrc->Init.InitValue);
  }


  /* set input data inversion mode */
  assert_param(IS_CRC_INPUTDATA_INVERSION_MODE(hcrc->Init.InputDataInversionMode));
  MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_IN, hcrc->Init.InputDataInversionMode);

  /* set output data inversion mode */
  assert_param(IS_CRC_OUTPUTDATA_INVERSION_MODE(hcrc->Init.OutputDataInversionMode));
  MODIFY_REG(hcrc->Instance->CR, CRC_CR_REV_OUT, hcrc->Init.OutputDataInversionMode);

  /* makes sure the input data format (bytes, halfwords or words stream)
   * is properly specified by user */
  assert_param(IS_CRC_INPUTDATA_FORMAT(hcrc->InputDataFormat));

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_READY;

  /* Return function status */
  return HAL_OK;
}

HAL_StatusTypeDef HAL_CRC_DeInit(CRC_HandleTypeDef *hcrc)
{
  /* Check the CRC handle allocation */
  if (hcrc == NULL)
  {
    return HAL_ERROR;
  }

  /* Check the parameters */
  assert_param(IS_CRC_ALL_INSTANCE(hcrc->Instance));

  /* Check the CRC peripheral state */
  if (hcrc->State == HAL_CRC_STATE_BUSY)
  {
    return HAL_BUSY;
  }

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_BUSY;

  /* Reset CRC calculation unit */
  __HAL_CRC_DR_RESET(hcrc);

  /* Reset IDR register content */
  CLEAR_BIT(hcrc->Instance->IDR, CRC_IDR_IDR);

  /* DeInit the low level hardware */
  HAL_CRC_MspDeInit(hcrc);

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_RESET;

  /* Process unlocked */
  __HAL_UNLOCK(hcrc);

  /* Return function status */
  return HAL_OK;
}

__weak void HAL_CRC_MspInit(CRC_HandleTypeDef *hcrc)
{
  /* Prevent unused argument(s) compilation warning */
  UNUSED(hcrc);

  /* NOTE : This function should not be modified, when the callback is needed,
            the HAL_CRC_MspInit can be implemented in the user file
   */
}

__weak void HAL_CRC_MspDeInit(CRC_HandleTypeDef *hcrc)
{
  /* Prevent unused argument(s) compilation warning */
  UNUSED(hcrc);

  /* NOTE : This function should not be modified, when the callback is needed,
            the HAL_CRC_MspDeInit can be implemented in the user file
   */
}

uint32_t HAL_CRC_Accumulate(CRC_HandleTypeDef *hcrc, uint32_t pBuffer[], uint32_t BufferLength)
{
  uint32_t index;      /* CRC input data buffer index */
  uint32_t temp = 0U;  /* CRC output (read from hcrc->Instance->DR register) */

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_BUSY;

  switch (hcrc->InputDataFormat)
  {
    case CRC_INPUTDATA_FORMAT_WORDS:
      /* Enter Data to the CRC calculator */
      for (index = 0U; index < BufferLength; index++)
      {
        hcrc->Instance->DR = pBuffer[index];
      }
      temp = hcrc->Instance->DR;
      break;

    case CRC_INPUTDATA_FORMAT_BYTES:
      temp = CRC_Handle_8(hcrc, (uint8_t *)pBuffer, BufferLength);
      break;

    case CRC_INPUTDATA_FORMAT_HALFWORDS:
      temp = CRC_Handle_16(hcrc, (uint16_t *)(void *)pBuffer, BufferLength);    /* Derogation MisraC2012 R.11.5 */
      break;
    default:
      break;
  }

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_READY;

  /* Return the CRC computed value */
  return temp;
}

uint32_t HAL_CRC_Calculate(CRC_HandleTypeDef *hcrc, uint32_t pBuffer[], uint32_t BufferLength)
{
  uint32_t index;      /* CRC input data buffer index */
  uint32_t temp = 0U;  /* CRC output (read from hcrc->Instance->DR register) */

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_BUSY;

  /* Reset CRC Calculation Unit (hcrc->Instance->INIT is
  *  written in hcrc->Instance->DR) */
  __HAL_CRC_DR_RESET(hcrc);

  switch (hcrc->InputDataFormat)
  {
    case CRC_INPUTDATA_FORMAT_WORDS:
      /* Enter 32-bit input data to the CRC calculator */
      for (index = 0U; index < BufferLength; index++)
      {
        hcrc->Instance->DR = pBuffer[index];
      }
      temp = hcrc->Instance->DR;
      break;

    case CRC_INPUTDATA_FORMAT_BYTES:
      /* Specific 8-bit input data handling  */
      temp = CRC_Handle_8(hcrc, (uint8_t *)pBuffer, BufferLength);
      break;

    case CRC_INPUTDATA_FORMAT_HALFWORDS:
      /* Specific 16-bit input data handling  */
      temp = CRC_Handle_16(hcrc, (uint16_t *)(void *)pBuffer, BufferLength);    /* Derogation MisraC2012 R.11.5 */
      break;

    default:
      break;
  }

  /* Change CRC peripheral state */
  hcrc->State = HAL_CRC_STATE_READY;

  /* Return the CRC computed value */
  return temp;
}

HAL_CRC_StateTypeDef HAL_CRC_GetState(CRC_HandleTypeDef *hcrc)
{
  /* Return CRC handle state */
  return hcrc->State;
}

static uint32_t CRC_Handle_8(CRC_HandleTypeDef *hcrc, uint8_t pBuffer[], uint32_t BufferLength)
{
  uint32_t i; /* input data buffer index */
  uint16_t data;
  __IO uint16_t *pReg;

  /* Processing time optimization: 4 bytes are entered in a row with a single word write,
   * last bytes must be carefully fed to the CRC calculator to ensure a correct type
   * handling by the peripheral */
  for (i = 0U; i < (BufferLength / 4U); i++)
  {
    hcrc->Instance->DR = ((uint32_t)pBuffer[4U * i] << 24U) | \
                         ((uint32_t)pBuffer[(4U * i) + 1U] << 16U) | \
                         ((uint32_t)pBuffer[(4U * i) + 2U] << 8U)  | \
                         (uint32_t)pBuffer[(4U * i) + 3U];
  }
  /* last bytes specific handling */
  if ((BufferLength % 4U) != 0U)
  {
    if ((BufferLength % 4U) == 1U)
    {
      *(__IO uint8_t *)(__IO void *)(&hcrc->Instance->DR) = pBuffer[4U * i];         /* Derogation MisraC2012 R.11.5 */
    }
    if ((BufferLength % 4U) == 2U)
    {
      data = ((uint16_t)(pBuffer[4U * i]) << 8U) | (uint16_t)pBuffer[(4U * i) + 1U];
      pReg = (__IO uint16_t *)(__IO void *)(&hcrc->Instance->DR);                    /* Derogation MisraC2012 R.11.5 */
      *pReg = data;
    }
    if ((BufferLength % 4U) == 3U)
    {
      data = ((uint16_t)(pBuffer[4U * i]) << 8U) | (uint16_t)pBuffer[(4U * i) + 1U];
      pReg = (__IO uint16_t *)(__IO void *)(&hcrc->Instance->DR);                    /* Derogation MisraC2012 R.11.5 */
      *pReg = data;

      *(__IO uint8_t *)(__IO void *)(&hcrc->Instance->DR) = pBuffer[(4U * i) + 2U];  /* Derogation MisraC2012 R.11.5 */
    }
  }

  /* Return the CRC computed value */
  return hcrc->Instance->DR;
}

static uint32_t CRC_Handle_16(CRC_HandleTypeDef *hcrc, uint16_t pBuffer[], uint32_t BufferLength)
{
  uint32_t i;  /* input data buffer index */
  __IO uint16_t *pReg;

  /* Processing time optimization: 2 HalfWords are entered in a row with a single word write,
   * in case of odd length, last HalfWord must be carefully fed to the CRC calculator to ensure
   * a correct type handling by the peripheral */
  for (i = 0U; i < (BufferLength / 2U); i++)
  {
    hcrc->Instance->DR = ((uint32_t)pBuffer[2U * i] << 16U) | (uint32_t)pBuffer[(2U * i) + 1U];
  }
  if ((BufferLength % 2U) != 0U)
  {
    pReg = (__IO uint16_t *)(__IO void *)(&hcrc->Instance->DR);                 /* Derogation MisraC2012 R.11.5 */
    *pReg = pBuffer[2U * i];
  }

  /* Return the CRC computed value */
  return hcrc->Instance->DR;
}

#endif /* HAL_CRC_MODULE_ENABLED */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/