2 files changed, 50 insertions, 0 deletions
diff --git a/include/libfdt.h b/include/libfdt.h
index 7403d5a..c5ec2ac 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -136,6 +136,28 @@ uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset);
 
 int fdt_next_node(const void *fdt, int offset, int *depth);
 
+/**
+ * fdt_first_subnode() - get offset of first direct subnode
+ *
+ * @fdt:	FDT blob
+ * @offset:	Offset of node to check
+ * @return offset of first subnode, or -FDT_ERR_NOTFOUND if there is none
+ */
+int fdt_first_subnode(const void *fdt, int offset);
+
+/**
+ * fdt_next_subnode() - get offset of next direct subnode
+ *
+ * After first calling fdt_first_subnode(), call this function repeatedly to
+ * get direct subnodes of a parent node.
+ *
+ * @fdt:	FDT blob
+ * @offset:	Offset of previous subnode
+ * @return offset of next subnode, or -FDT_ERR_NOTFOUND if there are no more
+ * subnodes
+ */
+int fdt_next_subnode(const void *fdt, int offset);
+
 /**********************************************************************/
 /* General functions                                                  */
 /**********************************************************************/
diff --git a/lib/libfdt/fdt.c b/lib/libfdt/fdt.c
index 387e354..154e9a4 100644
--- a/lib/libfdt/fdt.c
+++ b/lib/libfdt/fdt.c
@@ -202,6 +202,34 @@ int fdt_next_node(const void *fdt, int offset, int *depth)
 	return offset;
 }
 
+int fdt_first_subnode(const void *fdt, int offset)
+{
+	int depth = 0;
+
+	offset = fdt_next_node(fdt, offset, &depth);
+	if (offset < 0 || depth != 1)
+		return -FDT_ERR_NOTFOUND;
+
+	return offset;
+}
+
+int fdt_next_subnode(const void *fdt, int offset)
+{
+	int depth = 1;
+
+	/*
+	 * With respect to the parent, the depth of the next subnode will be
+	 * the same as the last.
+	 */
+	do {
+		offset = fdt_next_node(fdt, offset, &depth);
+		if (offset < 0 || depth < 1)
+			return -FDT_ERR_NOTFOUND;
+	} while (depth > 1);
+
+	return offset;
+}
+
 const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)
 {
 	int len = strlen(s) + 1;