libata: Add 32bit PIO support

This matters for some controllers and in one or two cases almost doubles
PIO performance. Add a bmdma32 operations set we can inherit and activate
it for some controllers

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/ata/pata_mpiix.c b/drivers/ata/pata_mpiix.c
index 7c8faa48..aa576ca 100644
--- a/drivers/ata/pata_mpiix.c
+++ b/drivers/ata/pata_mpiix.c
@@ -35,7 +35,7 @@
 #include <linux/libata.h>
 
 #define DRV_NAME "pata_mpiix"
-#define DRV_VERSION "0.7.6"
+#define DRV_VERSION "0.7.7"
 
 enum {
 	IDETIM = 0x6C,		/* IDE control register */
@@ -146,6 +146,7 @@
 	.cable_detect	= ata_cable_40wire,
 	.set_piomode	= mpiix_set_piomode,
 	.prereset	= mpiix_pre_reset,
+	.sff_data_xfer	= ata_sff_data_xfer32,
 };
 
 static int mpiix_init_one(struct pci_dev *dev, const struct pci_device_id *id)