dm: core: Add a way to find an ofnode by compatible string

Add an ofnode_by_compatible() to allow iterating through ofnodes with a
given compatible string.

Signed-off-by: Simon Glass <sjg@chromium.org>

drivers/core/ofnode.c

@@ -729,3 +729,15 @@ int ofnode_device_is_compatible(ofnode node, const char *compat)
 						  ofnode_to_offset(node),
 						  compat);
 }
+
+ofnode ofnode_by_compatible(ofnode from, const char *compat)
+{
+	if (of_live_active()) {
+		return np_to_ofnode(of_find_compatible_node(
+			(struct device_node *)ofnode_to_np(from), NULL,
+			compat));
+	} else {
+		return offset_to_ofnode(fdt_node_offset_by_compatible(
+				gd->fdt_blob, ofnode_to_offset(from), compat));
+	}
+}

include/dm/ofnode.h

@@ -679,6 +679,17 @@ int ofnode_read_resource_byname(ofnode node, const char *name,
 				struct resource *res);
 
 /**
+ * ofnode_by_compatible() - Find the next compatible node
+ *
+ * Find the next node after @from that is compatible with @compat
+ *
+ * @from: ofnode to start from (use ofnode_null() to start at the beginning)
+ * @compat: Compatible string to match
+ * @return ofnode found, or ofnode_null() if none
+ */
+ofnode ofnode_by_compatible(ofnode from, const char *compat);
+
+/**
  * ofnode_for_each_subnode() - iterate over all subnodes of a parent
  *
  * @node:       child node (ofnode, lvalue)