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

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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 <rich@bennellick.com>
This commit is contained in:
Rich Barlow 2021-03-18 16:27:51 +00:00 committed by Maureen Helm
parent 5ebb4214c9
commit 795d0577c9
1 changed files with 3 additions and 1 deletions
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4
subsys/disk/disk_access_spi_sdhc.c
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@ -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));
}