[PATCH 5/5] of: of_graph: add missing functions

[Sascha Hauer <s.hauer@pengutronix.de>]

This adds of_graph_get_endpoint_by_regs() and of_graph_get_remote_node()
as-is from Linux.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 drivers/of/base.c  | 64 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 include/of_graph.h |  4 ++++
 2 files changed, 68 insertions(+)

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 5981650f2a..960a9327ae 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -3358,6 +3358,32 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
 }
 EXPORT_SYMBOL(of_graph_get_next_endpoint);
 
+/**
+ * of_graph_get_endpoint_by_regs() - get endpoint node of specific identifiers
+ * @parent: pointer to the parent device node
+ * @port_reg: identifier (value of reg property) of the parent port node
+ * @reg: identifier (value of reg property) of the endpoint node
+ *
+ * Return: An 'endpoint' node pointer which is identified by reg and at the same
+ * is the child of a port node identified by port_reg. reg and port_reg are
+ * ignored when they are -1. Use of_node_put() on the pointer when done.
+ */
+struct device_node *of_graph_get_endpoint_by_regs(
+	const struct device_node *parent, int port_reg, int reg)
+{
+	struct of_endpoint endpoint;
+	struct device_node *node = NULL;
+
+	for_each_endpoint_of_node(parent, node) {
+		of_graph_parse_endpoint(node, &endpoint);
+		if (((port_reg == -1) || (endpoint.port == port_reg)) &&
+			((reg == -1) || (endpoint.id == reg)))
+			return node;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(of_graph_get_endpoint_by_regs);
+
 /**
  * of_graph_get_remote_port_parent() - get remote port's parent node
  * @node: pointer to a local endpoint device_node
@@ -3403,6 +3429,44 @@ struct device_node *of_graph_get_remote_port(const struct device_node *node)
 }
 EXPORT_SYMBOL(of_graph_get_remote_port);
 
+/**
+ * of_graph_get_remote_node() - get remote parent device_node for given port/endpoint
+ * @node: pointer to parent device_node containing graph port/endpoint
+ * @port: identifier (value of reg property) of the parent port node
+ * @endpoint: identifier (value of reg property) of the endpoint node
+ *
+ * Return: Remote device node associated with remote endpoint node linked
+ * to @node. Use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_remote_node(const struct device_node *node,
+					     u32 port, u32 endpoint)
+{
+	struct device_node *endpoint_node, *remote;
+
+	endpoint_node = of_graph_get_endpoint_by_regs(node, port, endpoint);
+	if (!endpoint_node) {
+		pr_debug("no valid endpoint (%d, %d) for node %pOF\n",
+			 port, endpoint, node);
+		return NULL;
+	}
+
+	remote = of_graph_get_remote_port_parent(endpoint_node);
+	of_node_put(endpoint_node);
+	if (!remote) {
+		pr_debug("no valid remote node\n");
+		return NULL;
+	}
+
+	if (!of_device_is_available(remote)) {
+		pr_debug("not available for remote node\n");
+		of_node_put(remote);
+		return NULL;
+	}
+
+	return remote;
+}
+EXPORT_SYMBOL(of_graph_get_remote_node);
+
 int of_graph_port_is_available(struct device_node *node)
 {
 	struct device_node *endpoint;
diff --git a/include/of_graph.h b/include/of_graph.h
index ef3fb8b94a..bd25643e25 100644
--- a/include/of_graph.h
+++ b/include/of_graph.h
@@ -43,5 +43,9 @@ 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);
 int of_graph_port_is_available(struct device_node *node);
+struct device_node *of_graph_get_remote_node(const struct device_node *node,
+					     u32 port, u32 endpoint);
+struct device_node *of_graph_get_endpoint_by_regs(
+	const struct device_node *parent, int port_reg, int reg);
 
 #endif /* __LINUX_OF_GRAPH_H */

-- 
2.39.5