tty: sunsu: Simplify device_node cleanup by using __free

Add `__free` function attribute to `ap` and `match` pointer
initialisations which ensure that the pointers are freed as soon as they
go out of scope, thus removing the need to manually free them using
`of_node_put`.

This also removes the need for the `goto` statement and the `rc`
variable.

Suggested-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Shresth Prasad <shresthprasad7@gmail.com>
Link: https://lore.kernel.org/r/20240518114051.18125-3-shresthprasad7@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/sunsu.c b/drivers/tty/serial/sunsu.c
index 67a5fc70bb4b9053e4beea14a6636b29cf33c1a5..0f463da5e7ce6830c32e047a529c1a475ace0bae 100644 (file)
--- a/drivers/tty/serial/sunsu.c
+++ b/drivers/tty/serial/sunsu.c
@@ -1382,44 +1382,29 @@ 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;
+       struct device_node *ap __free(device_node) =
+                           of_find_node_by_path("/aliases");
 
        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) {
-                       match = of_find_node_by_path(keyb);
+                       struct device_node *match __free(device_node) =
+                                           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 (dp == match)
+                               return SU_PORT_KBD;
                }
                if (ms) {
-                       match = of_find_node_by_path(ms);
+                       struct device_node *match __free(device_node) =
+                                           of_find_node_by_path(ms);
 
-                       of_node_put(match);
-
-                       if (dp == match) {
-                               rc = SU_PORT_MS;
-                               goto out;
-                       }
+                       if (dp == match)
+                               return SU_PORT_MS;
                }
        }
-
-out:
-       of_node_put(ap);
-       return rc;
+       return SU_PORT_PORT;
 }
 
 static int su_probe(struct platform_device *op)