extern int ata_xfer_mode2shift(unsigned long xfer_mode);
extern const char *ata_mode_string(unsigned long xfer_mask);
extern unsigned long ata_id_xfermask(const u16 *id);
extern int ata_xfer_mode2shift(unsigned long xfer_mode);
extern const char *ata_mode_string(unsigned long xfer_mask);
extern unsigned long ata_id_xfermask(const u16 *id);