diff options
| -rw-r--r-- | drivers/mfd/qnap-mcu.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/mfd/qnap-mcu.c b/drivers/mfd/qnap-mcu.c index 1f4741cad875..558c3bc07ed3 100644 --- a/drivers/mfd/qnap-mcu.c +++ b/drivers/mfd/qnap-mcu.c @@ -78,6 +78,13 @@ static u8 qnap_mcu_csum(const u8 *buf, size_t size) return csum; } +static bool qnap_mcu_verify_checksum(const u8 *buf, size_t size) +{ + u8 crc = qnap_mcu_csum(buf, size - QNAP_MCU_CHECKSUM_SIZE); + + return crc == buf[size - QNAP_MCU_CHECKSUM_SIZE]; +} + static int qnap_mcu_write(struct qnap_mcu *mcu, const u8 *data, u8 data_size) { unsigned char tx[QNAP_MCU_TX_BUFFER_SIZE]; @@ -150,7 +157,6 @@ int qnap_mcu_exec(struct qnap_mcu *mcu, size_t length = reply_data_size + QNAP_MCU_CHECKSUM_SIZE; struct qnap_mcu_reply *reply = &mcu->reply; int ret = 0; - u8 crc; if (length > sizeof(rx)) { dev_err(&mcu->serdev->dev, "expected data too big for receive buffer"); @@ -175,8 +181,7 @@ int qnap_mcu_exec(struct qnap_mcu *mcu, return -ETIMEDOUT; } - crc = qnap_mcu_csum(rx, reply->received - QNAP_MCU_CHECKSUM_SIZE); - if (crc != rx[reply->received - QNAP_MCU_CHECKSUM_SIZE]) { + if (!qnap_mcu_verify_checksum(rx, reply->received)) { dev_err(&mcu->serdev->dev, "Invalid Checksum received\n"); return -EPROTO; } |