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/include/linux/libata.h b/include/linux/libata.h
index 3449de5..4f7c8fb 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -1518,6 +1518,7 @@
 
 extern const struct ata_port_operations ata_sff_port_ops;
 extern const struct ata_port_operations ata_bmdma_port_ops;
+extern const struct ata_port_operations ata_bmdma32_port_ops;
 
 /* PIO only, sg_tablesize and dma_boundary limits can be removed */
 #define ATA_PIO_SHT(drv_name)					\
@@ -1545,6 +1546,8 @@
 				 const struct ata_taskfile *tf);
 extern unsigned int ata_sff_data_xfer(struct ata_device *dev,
 			unsigned char *buf, unsigned int buflen, int rw);
+extern unsigned int ata_sff_data_xfer32(struct ata_device *dev,
+			unsigned char *buf, unsigned int buflen, int rw);
 extern unsigned int ata_sff_data_xfer_noirq(struct ata_device *dev,
 			unsigned char *buf, unsigned int buflen, int rw);
 extern u8 ata_sff_irq_on(struct ata_port *ap);