[PATCH] libata: always use polling IDENTIFY

libata switched to IRQ-driven IDENTIFY when IRQ-driven PIO was
introduced.  This has caused a lot of problems including device
misdetection and phantom device.

ATA_FLAG_DETECT_POLLING was added recently to selectively use polling
IDENTIFY on problemetic drivers but many controllers and devices are
affected by this problem and trying to adding ATA_FLAG_DETECT_POLLING
for each such case is diffcult and not very rewarding.

This patch makes libata always use polling IDENTIFY.  This is
consistent with libata's original behavior and drivers/ide's behavior.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/libata.h

@@ -42,8 +42,6 @@ struct ata_scsi_args {
 enum {
 	/* flags for ata_dev_read_id() */
 	ATA_READID_POSTRESET	= (1 << 0), /* reading ID after reset */
-	ATA_READID_DETECT	= (1 << 1), /* perform presence detection
-					     * using polling IDENTIFY */
 };
 
 extern struct workqueue_struct *ata_aux_wq;