diff --git a/dbus.cpp b/dbus.cpp
index 70380d3..f0eb0b9 100644
--- a/dbus.cpp
+++ b/dbus.cpp
@@ -83,7 +83,7 @@
 }
 
 DbusSubtree getSubtree(sdbusplus::bus::bus& bus, const std::string& root,
-                       size_t depth, const std::string& interface)
+                       int depth, const std::string& interface)
 {
     DbusSubtree tree;