[PATCH] Suspend support for libata

This patch adds suspend patch to libata, and ata_piix in particular. For
most low level drivers, they should just need to add the 4 hooks to
work. As I can only test ata_piix, I didn't enable it for more
though.

Suspend support is the single most important feature on a notebook, and
most new notebooks have sata drives. It's quite embarrassing that we
_still_ do not support this. Right now, it's perfectly possible to
suspend the drive in mid-transfer.

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/scsi/scsi_host.h

@@ -295,6 +295,12 @@ struct scsi_host_template {
 	 */
 	int (*proc_info)(struct Scsi_Host *, char *, char **, off_t, int, int);
 
+	/*
+	 * suspend support
+	 */
+	int (*resume)(struct scsi_device *);
+	int (*suspend)(struct scsi_device *);
+
 	/*
 	 * Name of proc directory
 	 */