of: base: Add of_parse_phandle_from

Added of_parse_phandle_from() to be able to use external root nodes.

Signed-off-by: Teresa Gámez <t.gamez@phytec.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 24 insertions, 4 deletions

diff --git a/drivers/of/base.c b/drivers/of/base.c
index 061fc79e60..f363cc1224 100644
--- a/drivers/of/base.c
+++ b/drivers/of/base.c
@@ -1130,16 +1130,19 @@ int of_property_write_u64_array(struct device_node *np,
 }
 
 /**
- * of_parse_phandle - Resolve a phandle property to a device_node pointer
+ * of_parse_phandle_from - Resolve a phandle property to a device_node pointer from
+ * a given root node
  * @np: Pointer to device node holding phandle property
+ * @root: root node of the tree to search in. If NULL use the internal tree.
  * @phandle_name: Name of property holding a phandle value
  * @index: For properties holding a table of phandles, this is the index into
  *         the table
  *
  * Returns the device_node pointer found or NULL.
  */
-struct device_node *of_parse_phandle(const struct device_node *np,
-				     const char *phandle_name, int index)
+struct device_node *of_parse_phandle_from(const struct device_node *np,
+					struct device_node *root,
+					const char *phandle_name, int index)
 {
 	const __be32 *phandle;
 	int size;
@@ -1148,7 +1151,24 @@ struct device_node *of_parse_phandle(const struct device_node *np,
 	if ((!phandle) || (size < sizeof(*phandle) * (index + 1)))
 		return NULL;
 
-	return of_find_node_by_phandle(be32_to_cpup(phandle + index));
+	return of_find_node_by_phandle_from(be32_to_cpup(phandle + index),
+					root);
+}
+EXPORT_SYMBOL(of_parse_phandle_from);
+
+/**
+ * of_parse_phandle - Resolve a phandle property to a device_node pointer
+ * @np: Pointer to device node holding phandle property
+ * @phandle_name: Name of property holding a phandle value
+ * @index: For properties holding a table of phandles, this is the index into
+ *         the table
+ *
+ * Returns the device_node pointer found or NULL.
+ */
+struct device_node *of_parse_phandle(const struct device_node *np,
+				     const char *phandle_name, int index)
+{
+	return of_parse_phandle_from(np, root_node, phandle_name, index);
 }
 EXPORT_SYMBOL(of_parse_phandle);