dt: introduce of_get_child_by_name to get child node by name

This patch introduces of_get_child_by_name function to get a child node
by its name in a given parent node.

Without this patch each driver code has to iterate the parent and do
a string compare, However having of_get_child_by_name libary function would
avoid code duplication, errors and is more convenient.

Signed-off-by: Srinivas Kandagatla <[email protected]>
Signed-off-by: Rob Herring <[email protected]>
diff --git a/drivers/of/base.c b/drivers/of/base.c
index c181b94..e2e8136 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -364,6 +364,29 @@
 EXPORT_SYMBOL(of_get_next_child);
 
 /**
+ *	of_get_child_by_name - Find the child node by name for a given parent
+ *	@node:	parent node
+ *	@name:	child name to look for.
+ *
+ *      This function looks for child node for given matching name
+ *
+ *	Returns a node pointer if found, with refcount incremented, use
+ *	of_node_put() on it when done.
+ *	Returns NULL if node is not found.
+ */
+struct device_node *of_get_child_by_name(const struct device_node *node,
+				const char *name)
+{
+	struct device_node *child;
+
+	for_each_child_of_node(node, child)
+		if (child->name && (of_node_cmp(child->name, name) == 0))
+			break;
+	return child;
+}
+EXPORT_SYMBOL(of_get_child_by_name);
+
+/**
  *	of_find_node_by_path - Find a node matching a full OF path
  *	@path:	The full path to match
  *