of: Warn if of_graph_get_next_endpoint is called with the root node

If of_graph_get_next_endpoint is given a parentless node instead of an
endpoint node, it is clearly a bug.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Acked-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: Sylwester Nawrocki <s.nawrocki@samsung.com>

diff --git a/drivers/of/base.c b/drivers/of/base.c
index b2f223fa47e9e45bdd5d7b43b52b623be57f1a95..b5e690bd6e9c539f5f33fdeb5521410df1e3afec 100644 (file)
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -2028,8 +2028,8 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
                of_node_put(node);
        } else {
                port = of_get_parent(prev);
-               if (!port)
-                       /* Hm, has someone given us the root node ?... */
+               if (WARN_ONCE(!port, "%s(): endpoint %s has no parent node\n",
+                             __func__, prev->full_name))
                        return NULL;
 
                /* Avoid dropping prev node refcount to 0. */