libata: kill dead code paths in reset path

Some code paths which had been made obsolete by recent reset
simplification were still around.  Kill them.

* ata_eh_reset() checked for ATA_DEV_UNKNOWN to determine
  classification failure.  This is no longer applicable.

* ata_do_reset() should convert ATA_DEV_UNKNOWN to ATA_DEV_NONE
  regardless of reset result (e.g. -EAGAIN).

* LLDs don't need to convert ATA_DEV_UNKNOWN to ATA_DEV_NONE.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/libata-eh.c

@@ -2052,15 +2052,13 @@ static int ata_do_reset(struct ata_link *link, ata_reset_fn_t reset,
 		classes[dev->devno] = ATA_DEV_UNKNOWN;
 
 	rc = reset(link, classes, deadline);
-	if (rc)
-		return rc;
 
 	/* convert all ATA_DEV_UNKNOWN to ATA_DEV_NONE */
 	ata_link_for_each_dev(dev, link)
 		if (classes[dev->devno] == ATA_DEV_UNKNOWN)
 			classes[dev->devno] = ATA_DEV_NONE;
 
-	return 0;
+	return rc;
 }
 
 static int ata_eh_followup_srst_needed(struct ata_link *link,
@@ -2209,21 +2207,6 @@ int ata_eh_reset(struct ata_link *link, int classify,
 	if (rc && rc != -EAGAIN)
 		goto fail;
 
-	/* was classification successful? */
-	if (classify && classes[0] == ATA_DEV_UNKNOWN &&
-	    !(lflags & ATA_LFLAG_ASSUME_CLASS)) {
-		if (try < max_tries) {
-			ata_link_printk(link, KERN_WARNING,
-					"classification failed\n");
-			rc = -EINVAL;
-			goto fail;
-		}
-
-		ata_link_printk(link, KERN_WARNING,
-				"classfication failed, assuming ATA\n");
-		lflags |= ATA_LFLAG_ASSUME_ATA;
-	}
-
  done:
 	ata_link_for_each_dev(dev, link) {
 		/* After the reset, the device state is PIO 0 and the

drivers/ata/sata_inic162x.c

@@ -428,8 +428,6 @@ static int inic_hardreset(struct ata_link *link, unsigned int *class,
 
 		ata_sff_tf_read(ap, &tf);
 		*class = ata_dev_classify(&tf);
-		if (*class == ATA_DEV_UNKNOWN)
-			*class = ATA_DEV_NONE;
 	}
 
 	return 0;

drivers/ata/sata_sil24.c

@@ -693,9 +693,6 @@ static int sil24_softreset(struct ata_link *link, unsigned int *class,
 	sil24_read_tf(ap, 0, &tf);
 	*class = ata_dev_classify(&tf);
 
-	if (*class == ATA_DEV_UNKNOWN)
-		*class = ATA_DEV_NONE;
-
  out:
 	DPRINTK("EXIT, class=%u\n", *class);
 	return 0;