diff --git a/readd.cpp b/readd.cpp
index 95c6887..c7d0466 100644
--- a/readd.cpp
+++ b/readd.cpp
@@ -53,9 +53,17 @@
     // Finished getting options out, so cleanup the parser.
     options.reset();
 
+    // Determine the physical device sysfs path.
+    auto calloutPath = sysfs::findCalloutPath(path);
+    if (calloutPath.empty())
+    {
+        exit_with_error("Unable to determine callout path.", argv);
+    }
+
     MainLoop loop(
         sdbusplus::bus::new_default(),
         path,
+        calloutPath,
         BUSNAME_PREFIX,
         SENSOR_ROOT);
     loop.run();