diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 3882c72..c9838f1 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -2800,7 +2800,9 @@ static inline ata_xlat_func_t ata_get_xlat_func(struct ata_device *dev, u8 cmd)
 		return ata_scsi_start_stop_xlat;
 
 	case TEST_UNIT_READY:
-		return ata_scsi_tur_xlat;
+		if (ata_id_has_pm(dev->id))
+			return ata_scsi_tur_xlat;
+		return NULL;
 	}
 
 	return NULL;
@@ -3021,6 +3023,7 @@ void ata_scsi_simulate(struct ata_device *dev, struct scsi_cmnd *cmd,
 		case REZERO_UNIT:
 		case SEEK_6:
 		case SEEK_10:
+		case TEST_UNIT_READY:		/* only for !PM devices */
 			ata_scsi_rbuf_fill(&args, ata_scsiop_noop);
 			break;