diff --git a/dbus/util.hpp b/dbus/util.hpp
index e858c0c..44e137c 100644
--- a/dbus/util.hpp
+++ b/dbus/util.hpp
@@ -58,3 +58,4 @@
 
 std::string GetSensorPath(const std::string& type, const std::string& id);
 std::string GetMatch(const std::string& type, const std::string& id);
+bool ValidType(const std::string& type);