[PATCH] the latest consensus libata resume fix

Okay, just to sum things up.

This forces libata to wait for up to 2 seconds for BUSY|DRQ to clear
on resume before continuing.

[jgarzik adds...]  During testing we never saw DRQ asserted, but
nonetheless (a) this works and (b) testing for DRQ won't hurt.
Signed-off-by: NMark Lord <liml@rtr.ca>
Acked-by: NJens Axboe <axboe@suse.de>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/scsi/libata-core.c

@@ -4297,6 +4297,7 @@ static int ata_start_drive(struct ata_port *ap, struct ata_device *dev)
 int ata_device_resume(struct ata_port *ap, struct ata_device *dev)
 {
 	if (ap->flags & ATA_FLAG_SUSPENDED) {
+		ata_busy_wait(ap, ATA_BUSY | ATA_DRQ, 200000);
 		ap->flags &= ~ATA_FLAG_SUSPENDED;
 		ata_set_mode(ap);
 	}