diff --git a/services/surfaceflinger/EventThread.h b/services/surfaceflinger/EventThread.h
index 3f9d452..2e237dd 100644
--- a/services/surfaceflinger/EventThread.h
+++ b/services/surfaceflinger/EventThread.h
@@ -81,9 +81,11 @@
     virtual bool        threadLoop();
     virtual status_t    readyToRun();
     virtual void        onFirstRef();
-    virtual void onVSyncReceived(int, nsecs_t timestamp);
+    virtual void        onVSyncReceived(int, nsecs_t timestamp);
 
     void removeDisplayEventConnection(const wp<Connection>& connection);
+    void enableVSync();
+    void disableVSync();
 
     // constants
     sp<SurfaceFlinger> mFlinger;
@@ -99,6 +101,9 @@
 
     // main thread only
     size_t mDeliveredEvents;
+
+    // for debugging
+    bool mDebugVsyncEnabled;
 };
 
 // ---------------------------------------------------------------------------