Merge tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux

Pull devicetree changes from Grant Likely:
 "Here are the devicetree changes queued up for v4.1.  Nothing really
  exciting here.  Rob has another few commits for big-endian attached
  UARTs, but those will be sent in a separate merge request since they
  haven't been as thoroughly tested as this batch.

  Here are the highlights:

   - lots of unittest cleanup from Frank Rowand

   - bugfixes and updates to the of_graph code

   - tighten up of_get_mac_address() code

   - documentation updates"

* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux:
  of/unittest: Fix of_platform_depopulate test case
  of/unittest: early return from test skips tests
  of/unittest: breadcrumbs to reduce pain of future maintainers
  of/unittest: reduce checkpatch noise - line after declarations
  of/unittest: typo in error string
  of/unittest: add const where needed
  of_net: factor out repetitive code from of_get_mac_address()
  drivers/of: Add empty ranges quirk for PA-Semi
  of: Allow selection of OF_DYNAMIC and OF_OVERLAY if OF_UNITTEST
  of: Empty node & property flag accessors when !OF
  of: Explicitly include linux/types.h in of_graph.h
  dt-bindings: brcm: rationalize Broadcom documentation naming
  of/unittest: replace 'selftest' with 'unittest'
  Documentation: rename of_selftest.txt to of_unittest.txt
  Documentation: update the of_selftest.txt
  dt: OF_UNITTEST make dependency broken
  MAINTAINERS: Pantelis Antoniou device tree overlay maintainer
  of: Add of_graph_get_port_by_id function
  of: Add for_each_endpoint_of_node helper macro
  of: Decrement refcount of previous endpoint in of_graph_get_next_endpoint

drivers/of/base.c

@@ -2108,14 +2108,45 @@ int of_graph_parse_endpoint(const struct device_node *node,
 }
 EXPORT_SYMBOL(of_graph_parse_endpoint);
 
+/**
+ * of_graph_get_port_by_id() - get the port matching a given id
+ * @parent: pointer to the parent device node
+ * @id: id of the port
+ *
+ * Return: A 'port' node pointer with refcount incremented. The caller
+ * has to use of_node_put() on it when done.
+ */
+struct device_node *of_graph_get_port_by_id(struct device_node *parent, u32 id)
+{
+	struct device_node *node, *port;
+
+	node = of_get_child_by_name(parent, "ports");
+	if (node)
+		parent = node;
+
+	for_each_child_of_node(parent, port) {
+		u32 port_id = 0;
+
+		if (of_node_cmp(port->name, "port") != 0)
+			continue;
+		of_property_read_u32(port, "reg", &port_id);
+		if (id == port_id)
+			break;
+	}
+
+	of_node_put(node);
+
+	return port;
+}
+EXPORT_SYMBOL(of_graph_get_port_by_id);
+
 /**
  * of_graph_get_next_endpoint() - get next endpoint node
  * @parent: pointer to the parent device node
  * @prev: previous endpoint node, or NULL to get first
  *
  * Return: An 'endpoint' node pointer with refcount incremented. Refcount
- * of the passed @prev node is not decremented, the caller have to use
- * of_node_put() on it when done.
+ * of the passed @prev node is decremented.
  */
 struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
 					struct device_node *prev)
@@ -2151,12 +2182,6 @@ struct device_node *of_graph_get_next_endpoint(const struct device_node *parent,
 		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 when getting the next
-		 * child below.
-		 */
-		of_node_get(prev);
 	}
 
 	while (1) {