ses: requesting a fault indication

commit 2a350cab upstream.

Noticed that when the sysfs interface of the SCSI SES
driver was used to request a fault indication the LED
flashed but the buzzer didn't sound. So it was doing
what REQUEST IDENT (locate) should do.

Changelog:
   - fix the setting of REQUEST FAULT for the device slot
     and array device slot elements in the enclosure control
     diagnostic page
   - note the potentially defective code that reads the
     FAULT SENSED and FAULT REQUESTED bits from the enclosure
     status diagnostic page

The attached patch is against git/scsi-misc-2.6
Signed-off-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/scsi/ses.c

@@ -160,6 +160,10 @@ static unsigned char *ses_get_page2_descriptor(struct enclosure_device *edev,
 	return NULL;
 }
 
+/* For device slot and array device slot elements, byte 3 bit 6
+ * is "fault sensed" while byte 3 bit 5 is "fault reqstd". As this
+ * code stands these bits are shifted 4 positions right so in
+ * sysfs they will appear as bits 2 and 1 respectively. Strange. */
 static void ses_get_fault(struct enclosure_device *edev,
 			  struct enclosure_component *ecomp)
 {
@@ -181,7 +185,7 @@ static int ses_set_fault(struct enclosure_device *edev,
 		/* zero is disabled */
 		break;
 	case ENCLOSURE_SETTING_ENABLED:
-		desc[2] = 0x02;
+		desc[3] = 0x20;
 		break;
 	default:
 		/* SES doesn't do the SGPIO blink settings */