[U-Boot] [PATCH 05/23] fdt: Add a subnodes iterator macro

Thierry Reding
2014-08-18T07:16:18Z

From: Thierry Reding <treding@nvidia.com>

The fdt_for_each_subnode() iterator macro provided by this patch can be
used to iterate over a device tree node's subnodes. At each iteration a
loop variable will be set to the next subnode.

Signed-off-by: Thierry Reding <treding@nvidia.com>
---
include/libfdt.h | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)

diff --git a/include/libfdt.h b/include/libfdt.h
index 4d7fb2681669..0330d7a29a58 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -163,6 +163,26 @@ int fdt_first_subnode(const void *fdt, int offset);
*/
int fdt_next_subnode(const void *fdt, int offset);

+/**
+ * fdt_for_each_subnode - iterate over all subnodes of a parent
+ *
+ * This is actually a wrapper around a for loop and would be used like so:
+ *
+ * fdt_for_each_subnode(fdt, node, parent) {
+ * ...
+ * use node
+ * ...
+ * }
+ *
+ * @fdt: FDT blob
+ * @node: child node
+ * @parent: parent node
+ */
+#define fdt_for_each_subnode(fdt, node, parent) \
+ for (node = fdt_first_subnode(fdt, parent); \
+ node >= 0; \
+ node = fdt_next_subnode(fdt, node))
+
/**********************************************************************/
/* General functions */
/**********************************************************************/
--
2.0.4