diff options
| -rw-r--r-- | drivers/scsi/scsi.c | 37 |
1 files changed, 14 insertions, 23 deletions
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c index c4bf99a842f3..d0911bc28663 100644 --- a/drivers/scsi/scsi.c +++ b/drivers/scsi/scsi.c @@ -586,31 +586,22 @@ static bool scsi_cdl_check_cmd(struct scsi_device *sdev, u8 opcode, u16 sa, if ((buf[1] & 0x03) != 0x03) return false; - /* See SPC-6, one command format of REPORT SUPPORTED OPERATION CODES */ + /* + * See SPC-6, One_command parameter data format for + * REPORT SUPPORTED OPERATION CODES. We have the following cases + * depending on rwcdlp (buf[0] & 0x01) value: + * - rwcdlp == 0: then cdlp indicates support for the A mode page when + * it is equal to 1 and for the B mode page when it is + * equal to 2. + * - rwcdlp == 1: then cdlp indicates support for the T2A mode page + * when it is equal to 1 and for the T2B mode page when + * it is equal to 2. + * Overall, to detect support for command duration limits, we only need + * to check that cdlp is 1 or 2. + */ cdlp = (buf[1] & 0x18) >> 3; - if (buf[0] & 0x01) { - /* rwcdlp == 1 */ - switch (cdlp) { - case 0x01: - /* T2A page */ - return true; - case 0x02: - /* T2B page */ - return true; - } - } else { - /* rwcdlp == 0 */ - switch (cdlp) { - case 0x01: - /* A page */ - return true; - case 0x02: - /* B page */ - return true; - } - } - return false; + return cdlp == 0x01 || cdlp == 0x02; } /** |