[PATCH] libata: add 40pin "short" cable support, honour drive side speed detection
[deweerdt@free.fr: build fix]
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Frederik Deweerdt <deweerdt@free.fr>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 915a55a..b896119 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -3119,6 +3119,13 @@
*/
if (ap->cbl == ATA_CBL_PATA40)
xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
+ /* Apply drive side cable rule. Unknown or 80 pin cables reported
+ * host side are checked drive side as well. Cases where we know a
+ * 40wire cable is used safely for 80 are not checked here.
+ */
+ if (ata_drive_40wire(dev->id) && (ap->cbl == ATA_CBL_PATA_UNK || ap->cbl == ATA_CBL_PATA80))
+ xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
+
xfer_mask &= ata_pack_xfermask(dev->pio_mask,
dev->mwdma_mask, dev->udma_mask);