libfdt: Add fdt_path_offset_namelen

Add a namelen variant of fdt_path_offset to retrieve the node offset using
only a fixed number of characters.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
diff --git a/include/libfdt.h b/include/libfdt.h
index 4643be5..f13b01f 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -366,6 +366,17 @@
 int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
 
 /**
+ * fdt_path_offset_namelen - find a tree node based on substring
+ * @fdt: pointer to the device tree blob
+ * @path: full path of the node to locate
+ * @namelen: number of characters of name to consider
+ *
+ * Identical to fdt_path_offset(), but only examine the first
+ * namelen characters of path for matching the node path.
+ */
+int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen);
+
+/**
  * fdt_path_offset - find a tree node by its full path
  * @fdt: pointer to the device tree blob
  * @path: full path of the node to locate
@@ -387,7 +398,10 @@
  *	-FDT_ERR_BADSTRUCTURE,
  *	-FDT_ERR_TRUNCATED, standard meanings.
  */
-int fdt_path_offset(const void *fdt, const char *path);
+static inline int fdt_path_offset(const void *fdt, const char *path)
+{
+	return fdt_path_offset_namelen(fdt, path, strlen(path));
+}
 
 /**
  * fdt_get_name - retrieve the name of a given node