of_graph: add of_graph_get_port_parent()

Linux kernel already has of_graph_get_remote_port_parent(),
but, sometimes we want to get own port parent.
This patch adds of_graph_get_port_parent()

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

2 files changed, 29 insertions, 8 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index b169508a9b56..4c305599a664 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -2501,6 +2501,27 @@ struct device_node *of_graph_get_remote_endpoint(const struct device_node *node)
 EXPORT_SYMBOL(of_graph_get_remote_endpoint);
 
 /**
+ * of_graph_get_port_parent() - get port's parent node
+ * @node: pointer to a local endpoint device_node
+ *
+ * Return: device node associated with endpoint node linked
+ *         to @node. Use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_port_parent(struct device_node *node)
+{
+        unsigned int depth;
+
+        /* Walk 3 levels up only if there is 'ports' node. */
+        for (depth = 3; depth && node; depth--) {
+                node = of_get_next_parent(node);
+                if (depth == 2 && of_node_cmp(node->name, "ports"))
+                        break;
+        }
+        return node;
+}
+EXPORT_SYMBOL(of_graph_get_port_parent);
+
+/**
  * of_graph_get_remote_port_parent() - get remote port's parent node
  * @node: pointer to a local endpoint device_node
  *
@@ -2511,18 +2532,11 @@ struct device_node *of_graph_get_remote_port_parent(
                                const struct device_node *node)
 {
         struct device_node *np;
-        unsigned int depth;
 
         /* Get remote endpoint node. */
         np = of_graph_get_remote_endpoint(node);
 
-        /* Walk 3 levels up only if there is 'ports' node. */
-        for (depth = 3; depth && np; depth--) {
-                np = of_get_next_parent(np);
-                if (depth == 2 && of_node_cmp(np->name, "ports"))
-                        break;
-        }
-        return np;
+        return of_graph_get_port_parent(np);
 }
 EXPORT_SYMBOL(of_graph_get_remote_port_parent);
 
diff --git a/include/linux/of_graph.h b/include/linux/of_graph.h
index 0c9473a169dd..9db632d16cbc 100644
--- a/include/linux/of_graph.h
+++ b/include/linux/of_graph.h
@@ -50,6 +50,7 @@ struct device_node *of_graph_get_endpoint_by_regs(
                 const struct device_node *parent, int port_reg, int reg);
 struct device_node *of_graph_get_remote_endpoint(
                                         const struct device_node *node);
+struct device_node *of_graph_get_port_parent(struct device_node *node);
 struct device_node *of_graph_get_remote_port_parent(
                                         const struct device_node *node);
 struct device_node *of_graph_get_remote_port(const struct device_node *node);
@@ -88,6 +89,12 @@ static inline struct device_node *of_graph_get_remote_endpoint(
         return NULL;
 }
 
+static inline struct device_node *of_graph_get_port_parent(
+        struct device_node *node)
+{
+        return NULL;
+}
+
 static inline struct device_node *of_graph_get_remote_port_parent(
                                         const struct device_node *node)
 {