/*
  * Tear down a previously set up module.
  */
-void gb_interface_destroy(struct gb_interface *intf)
+static void interface_destroy(struct gb_interface *intf)
 {
        struct gb_module *module;
        struct gb_bundle *bundle;
        struct gb_interface *intf = gb_interface_find(hd, interface_id);
 
        if (intf)
-               gb_interface_destroy(intf);
+               interface_destroy(intf);
        else
                dev_err(hd->parent, "interface id %d not found\n",
                        interface_id);
        struct gb_interface *intf, *temp;
 
        list_for_each_entry_safe(intf, temp, &hd->interfaces, links)
-               gb_interface_destroy(intf);
+               interface_destroy(intf);
 }