disk: sdhc: Set LSB of command to 1 as end bit

The SD Card Physical Layer specification states in Table 7-1 (in section 7.3.1.1) that the LSB of the 48 bit command must be set to 1 to act as an 'end bit'. Fixes #33479 Signed-off-by: Rich Barlow <[email protected]>
zephyrproject-rtos · Mar 19, 2021 · 795d057 · 795d057
1 parent 5ebb421
commit 795d057
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/subsys/disk/disk_access_spi_sdhc.c b/subsys/disk/disk_access_spi_sdhc.c
@@ -146,7 +146,9 @@ static int sdhc_spi_tx_cmd(struct sdhc_spi_data *data, uint8_t cmd, uint32_t pay
  /* Encode the command */
  buf[0] = SDHC_TX | (cmd & ~SDHC_START);
  sys_put_be32(payload, &buf[1]);
- buf[SDHC_CMD_BODY_SIZE] = crc7_be(0, buf, SDHC_CMD_BODY_SIZE);
+
+ /* Add CRC and set LSB as 'end bit' */
+ buf[SDHC_CMD_BODY_SIZE] = crc7_be(0, buf, SDHC_CMD_BODY_SIZE) | 0x01;
 
  return sdhc_spi_tx(data, buf, sizeof(buf));
 }