Check bit 2 of Word 53 for Word 88 validity before using Word 88 to determine UDMA mask. Note that the original xfer mask implementation using ata_get_mode_mask() didn't consider bit 2 of Word 53. This patch introduces different (correct) behavior. Signed-off-by: Tejun Heo <htejun@xxxxxxxxx> --- libata-core.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c index 42d43b5..e2529e9 100644 --- a/drivers/scsi/libata-core.c +++ b/drivers/scsi/libata-core.c @@ -819,7 +819,10 @@ static unsigned int ata_id_xfermask(cons } mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07; - udma_mask = id[ATA_ID_UDMA_MODES] & 0xff; + + udma_mask = 0; + if (id[ATA_ID_FIELD_VALID] & (1 << 2)) + udma_mask = id[ATA_ID_UDMA_MODES] & 0xff; return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask); } - : send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
