[PATCH 3/8] dm: core: implement ofnode/tree_parse_phandle() helper

[Christian Marangi <ansuelsmth@gmail.com>]

Implement ofnode/tree_parse_phandle() helper as an equivalent of
of_parse_phandle to handle simple single value phandle.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 drivers/core/ofnode.c | 58 +++++++++++++++++++++++++++++++++++++++++++
 include/dm/ofnode.h   | 26 +++++++++++++++++++
 2 files changed, 84 insertions(+)

diff --git a/drivers/core/ofnode.c b/drivers/core/ofnode.c
index a2136f61b7d..774b428c43f 100644
--- a/drivers/core/ofnode.c
+++ b/drivers/core/ofnode.c
@@ -879,6 +879,64 @@ int ofnode_read_string_list(ofnode node, const char *property,
 	return count;
 }
 
+ofnode ofnode_parse_phandle(ofnode node, const char *phandle_name,
+			    int index)
+{
+	ofnode phandle;
+
+	if (ofnode_is_np(node)) {
+		struct device_node *np;
+
+		np = of_parse_phandle(ofnode_to_np(node), phandle_name,
+				      index);
+		if (!np)
+			return ofnode_null();
+
+		phandle = np_to_ofnode(np);
+	} else {
+		struct fdtdec_phandle_args args;
+
+		if (fdtdec_parse_phandle_with_args(ofnode_to_fdt(node),
+						   ofnode_to_offset(node),
+						   phandle_name, NULL,
+						   0, index, &args))
+			return ofnode_null();
+
+		phandle = offset_to_ofnode(args.node);
+	}
+
+	return phandle;
+}
+
+ofnode oftree_parse_phandle(oftree tree, ofnode node, const char *phandle_name,
+			    int index)
+{
+	ofnode phandle;
+
+	if (ofnode_is_np(node)) {
+		struct device_node *np;
+
+		np = of_root_parse_phandle(tree.np, ofnode_to_np(node),
+					   phandle_name, index);
+		if (!np)
+			return ofnode_null();
+
+		phandle = np_to_ofnode(np);
+	} else {
+		struct fdtdec_phandle_args args;
+
+		if (fdtdec_parse_phandle_with_args(tree.fdt,
+						   ofnode_to_offset(node),
+						   phandle_name, NULL,
+						   0, index, &args))
+			return ofnode_null();
+
+		phandle = offset_to_ofnode(args.node);
+	}
+
+	return phandle;
+}
+
 static void ofnode_from_fdtdec_phandle_args(struct fdtdec_phandle_args *in,
 					    struct ofnode_phandle_args *out)
 {
diff --git a/include/dm/ofnode.h b/include/dm/ofnode.h
index 7ece68874ae..eea6b13217c 100644
--- a/include/dm/ofnode.h
+++ b/include/dm/ofnode.h
@@ -847,6 +847,18 @@ int ofnode_read_string_count(ofnode node, const char *property);
 int ofnode_read_string_list(ofnode node, const char *property,
 			    const char ***listp);
 
+/**
+ * ofnode_parse_phandle() - Resolve a phandle property to an ofnode
+ *
+ * @node: node to check
+ * @phandle_name: Name of property holding a phandle value
+ * @index: For properties holding a table of phandles, this is the index into
+ *         the table
+ * Return: ofnode that the phandle points to or ofnode_null() on error.
+ */
+ofnode ofnode_parse_phandle(ofnode node, const char *phandle_name,
+			    int index);
+
 /**
  * ofnode_parse_phandle_with_args() - Find a node pointed by phandle in a list
  *
@@ -909,6 +921,20 @@ int ofnode_parse_phandle_with_args(ofnode node, const char *list_name,
 int ofnode_count_phandle_with_args(ofnode node, const char *list_name,
 				   const char *cells_name, int cell_count);
 
+/**
+ * oftree_parse_phandle() - Resolve a phandle property to an ofnode
+ *			    from a root node
+ *
+ * @tree: device tree to use
+ * @node: node to check
+ * @phandle_name: Name of property holding a phandle value
+ * @index: For properties holding a table of phandles, this is the index into
+ *         the table
+ * Return: ofnode that the phandle points to or ofnode_null() on error.
+ */
+ofnode oftree_parse_phandle(oftree tree, ofnode node, const char *phandle_name,
+			    int index);
+
 /**
  * oftree_parse_phandle_with_args() - Find a node pointed by phandle in a list
  *				      from a root node
-- 
2.45.2