File content as of revision 186:707f6e361f3e:

#include "crc_api.h"
#include "device.h"

#include "platform/mbed_assert.h"

#ifdef DEVICE_CRC

static CRC_HandleTypeDef current_state;
static uint32_t final_xor;

bool hal_crc_is_supported(const crc_mbed_config_t* config)
{
  if (config == NULL) {
    return false;
  }

  if (config->polynomial != POLY_32BIT_ANSI) {
    return false;
  }

  if (config->width != 32) {
    return false;
  }

  if ((config->final_xor != 0xFFFFFFFFU) && (config->final_xor != 0)) {
    return false;
  }

  return true;
}

void hal_crc_compute_partial_start(const crc_mbed_config_t* config)
{
  MBED_ASSERT(hal_crc_is_supported(config));

  __HAL_RCC_CRC_CLK_ENABLE();

  final_xor = config->final_xor;

  current_state.Instance                     = CRC;
  current_state.InputDataFormat              = CRC_INPUTDATA_FORMAT_BYTES;
  current_state.Init.DefaultPolynomialUse    = DEFAULT_POLYNOMIAL_ENABLE;
  current_state.Init.DefaultInitValueUse     = DEFAULT_INIT_VALUE_DISABLE;
  current_state.Init.InitValue               = config->initial_xor;
  current_state.Init.CRCLength               = CRC_POLYLENGTH_32B;
  current_state.Init.InputDataInversionMode  =
    config->reflect_in ? CRC_INPUTDATA_INVERSION_BYTE
                       : CRC_INPUTDATA_INVERSION_NONE;
  current_state.Init.OutputDataInversionMode =
    config->reflect_out ? CRC_OUTPUTDATA_INVERSION_ENABLE
                        : CRC_OUTPUTDATA_INVERSION_DISABLE;

  HAL_CRC_Init(&current_state);
}

void hal_crc_compute_partial(const uint8_t *data, const size_t size)
{
  if (data && size) {
      HAL_CRC_Accumulate(&current_state, (uint32_t *)data, size);
  }
}

uint32_t hal_crc_get_result(void)
{
  const uint32_t result = current_state.Instance->DR;

  return (final_xor == 0xFFFFFFFFU) ? ~result : result;
}

#endif // DEVICE_CRC