libfdt: Add iterator over properties
Implement a macro based on fdt_first_property_offset and
fdt_next_property_offset that provides a convenience to iterate over all
the properties of a given node.
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/include/libfdt.h b/include/libfdt.h
index 74b1d14..fbbe58c 100644
--- a/include/libfdt.h
+++ b/include/libfdt.h
@@ -441,6 +441,30 @@
int fdt_next_property_offset(const void *fdt, int offset);
/**
+ * fdt_for_each_property - iterate over all properties of a node
+ * @property_offset: property offset (int)
+ * @fdt: FDT blob (const void *)
+ * @node: node offset (int)
+ *
+ * This is actually a wrapper around a for loop and would be used like so:
+ *
+ * fdt_for_each_property(fdt, node, property) {
+ * ...
+ * use property
+ * ...
+ * }
+ *
+ * Note that this is implemented as a macro and property is used as
+ * iterator in the loop. It should therefore be a locally allocated
+ * variable. The node variable on the other hand is never modified, so
+ * it can be constant or even a literal.
+ */
+#define fdt_for_each_property_offset(property, fdt, node) \
+ for (property = fdt_first_property_offset(fdt, node); \
+ property >= 0; \
+ property = fdt_next_property_offset(fdt, property))
+
+/**
* fdt_get_property_by_offset - retrieve the property at a given offset
* @fdt: pointer to the device tree blob
* @offset: offset of the property to retrieve