serial/sunsu: fix refcount leak

index 6cf3e9b0728f..c5428b0426a9 100644
@@ -1394,22 +1394,43 @@ static inline struct console *SUNSU_CONSOLE(void)
 static enum su_type su_get_type(struct device_node *dp)
 {
 	struct device_node *ap = of_find_node_by_path("/aliases");
+	enum su_type rc = SU_PORT_PORT;
 
 	if (ap) {
 		const char *keyb = of_get_property(ap, "keyboard", NULL);
 		const char *ms = of_get_property(ap, "mouse", NULL);
+		struct device_node *match;
 
 		if (keyb) {
-			if (dp == of_find_node_by_path(keyb))
-				return SU_PORT_KBD;
+			match = of_find_node_by_path(keyb);
+
+			/*
+			 * The pointer is used as an identifier not
+			 * as a pointer, we can drop the refcount on
+			 * the of__node immediately after getting it.
+			 */
+			of_node_put(match);
+
+			if (dp == match) {
+				rc = SU_PORT_KBD;
+				goto out;
+			}
 		}
 		if (ms) {
-			if (dp == of_find_node_by_path(ms))
-				return SU_PORT_MS;
+			match = of_find_node_by_path(ms);
+
+			of_node_put(match);
+
+			if (dp == match) {
+				rc = SU_PORT_MS;
+				goto out;
+			}
 		}
 	}
 
-	return SU_PORT_PORT;
+out:
+	of_node_put(ap);
+	return rc;
 }
 
 static int su_probe(struct platform_device *op)