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.
Acked-by: Simon Glass sjg@chromium.org Signed-off-by: Thierry Reding treding@nvidia.com --- Changes in v2: - specify the data types in the comment because the macro doesn't have them
include/libfdt.h | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+)
diff --git a/include/libfdt.h b/include/libfdt.h index 2dfc6d9e5ce7..f3cbb637be41 100644 --- a/include/libfdt.h +++ b/include/libfdt.h @@ -163,6 +163,31 @@ 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 + * ... + * } + * + * Note that this is implemented as a macro and node is used as iterator in + * the loop. It should therefore be a locally allocated variable. The parent + * variable on the other hand is never modified, so it can be constant or + * even a literal. + * + * @fdt: FDT blob (const void *) + * @node: child node (int) + * @parent: parent node (int) + */ +#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 */ /**********************************************************************/