libata: export xfermode / PATA timing related functions

Export the following xfermode related functions.

* ata_pack_xfermask()
* ata_unpack_xfermask()
* ata_xfer_mask2mode()
* ata_xfer_mode2mask()
* ata_xfer_mode2shift()
* ata_mode_string()
* ata_id_xfermask()
* ata_timing_find_mode()

These functions will be used later by LLD updates.  While at it,
change unsigned short @speed to u8 @xfer_mode in
ata_timing_find_mode() for consistency.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 131fb66..083dd77 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -851,6 +851,15 @@
 extern void ata_tf_to_fis(const struct ata_taskfile *tf,
 			  u8 pmp, int is_cmd, u8 *fis);
 extern void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf);
+extern unsigned int ata_pack_xfermask(unsigned int pio_mask,
+			unsigned int mwdma_mask, unsigned int udma_mask);
+extern void ata_unpack_xfermask(unsigned int xfer_mask, unsigned int *pio_mask,
+			unsigned int *mwdma_mask, unsigned int *udma_mask);
+extern u8 ata_xfer_mask2mode(unsigned int xfer_mask);
+extern unsigned int ata_xfer_mode2mask(u8 xfer_mode);
+extern int ata_xfer_mode2shift(unsigned int xfer_mode);
+extern const char *ata_mode_string(unsigned int xfer_mask);
+extern unsigned int ata_id_xfermask(const u16 *id);
 extern void ata_noop_dev_select(struct ata_port *ap, unsigned int device);
 extern void ata_std_dev_select(struct ata_port *ap, unsigned int device);
 extern u8 ata_check_status(struct ata_port *ap);
@@ -920,6 +929,7 @@
  */
 
 extern unsigned int ata_pio_need_iordy(const struct ata_device *);
+extern const struct ata_timing *ata_timing_find_mode(u8 xfer_mode);
 extern int ata_timing_compute(struct ata_device *, unsigned short,
 			      struct ata_timing *, int, int);
 extern void ata_timing_merge(const struct ata_timing *,