Linux-libre 4.2-gnu

1 files changed, 34 insertions, 0 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 5ed97246c..8b5a187a7 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -2231,6 +2231,40 @@ 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.
+ */
+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, *prev_node = NULL;
+
+	while (1) {
+		node = of_graph_get_next_endpoint(parent, prev_node);
+		of_node_put(prev_node);
+		if (!node)
+			break;
+
+		of_graph_parse_endpoint(node, &endpoint);
+		if (((port_reg == -1) || (endpoint.port == port_reg)) &&
+			((reg == -1) || (endpoint.id == reg)))
+			return node;
+
+		prev_node = 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
  *