[PATCH] libata: fix pio_mask values (take 2)

ata_get_mode_mask() uses bits 3 and 4 in the pio_mask to represent PIO
modes 3 and 4.  The value read from the drive, which reports support
for PIO3 and PIO4 in bits 0 and 1, is shifted left by 3 bits and OR'd
with 0x7 (which then corresponds to PIO 2-0 in libata).  Thus, the
drivers below need adjustments to comply with the way pio_mask is
used.  I changed the masks from the commented values to all support
PIO4-0, since the spec mandates that PIO0-2 are supported and there's
no reason not to support PIO3 IMO.

Signed-off-by: Brett Russ <russb@emc.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index 3106526..320df6c 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -250,7 +250,7 @@
 		.host_flags	= ATA_FLAG_SATA | ATA_FLAG_NO_LEGACY |
 				  ATA_FLAG_SATA_RESET | ATA_FLAG_MMIO |
 				  ATA_FLAG_PIO_DMA,
-		.pio_mask	= 0x03, /* pio3-4 */
+		.pio_mask	= 0x1f, /* pio0-4 */
 		.udma_mask	= 0x7f, /* udma0-6 ; FIXME */
 		.port_ops	= &ahci_ops,
 	},