/**
* @brief Prepares card to handle read transaction.
*
* @param[in] sdcp pointer to the @p SDCDriver object
* @param[in] startblk first block to read
* @param[in] n number of blocks to read
* @param[in] resp pointer to the response buffer
*
* @return The operation status.
* @retval CH_SUCCESS operation succeeded.
* @retval CH_FAILED operation failed.
*
* @notapi
*/
static bool_t sdc_lld_prepare_read(SDCDriver *sdcp, uint32_t startblk,
uint32_t n, uint32_t *resp) {
/* Driver handles data in 512 bytes blocks (just like HC cards). But if we
have not HC card than we must convert address from blocks to bytes.*/
if (!(sdcp->cardmode & SDC_MODE_HIGH_CAPACITY))
startblk *= MMCSD_BLOCK_SIZE;
if (n > 1) {
/* Send read multiple blocks command to card.*/
if (sdc_lld_send_cmd_short_crc(sdcp, MMCSD_CMD_READ_MULTIPLE_BLOCK,
startblk, resp) || MMCSD_R1_ERROR(resp[0]))
return CH_FAILED;
}
else{
/* Send read single block command.*/
if (sdc_lld_send_cmd_short_crc(sdcp, MMCSD_CMD_READ_SINGLE_BLOCK,
startblk, resp) || MMCSD_R1_ERROR(resp[0]))
return CH_FAILED;
}
return CH_SUCCESS;
}
/**
* @brief Reads special registers using data bus.
* @details Needs only during card detection procedure.
*
* @param[in] sdcp pointer to the @p SDCDriver object
* @param[out] buf pointer to the read buffer
* @param[in] bytes number of bytes to read
* @param[in] cmd card command
* @param[in] arg argument for command
*
* @return The operation status.
* @retval HAL_SUCCESS operation succeeded.
* @retval HAL_FAILED operation failed.
*
* @notapi
*/
bool sdc_lld_read_special(SDCDriver *sdcp, uint8_t *buf, size_t bytes,
uint8_t cmd, uint32_t arg) {
uint32_t resp[1];
if(sdc_lld_prepare_read_bytes(sdcp, buf, bytes))
goto error;
if (sdc_lld_send_cmd_short_crc(sdcp, cmd, arg, resp)
|| MMCSD_R1_ERROR(resp[0]))
goto error;
if (sdc_lld_wait_transaction_end(sdcp, 1, resp))
goto error;
return HAL_SUCCESS;
error:
sdc_lld_error_cleanup(sdcp, 1, resp);
return HAL_FAILED;
}