diff --git a/services/surfaceflinger/DisplayDevice.h b/services/surfaceflinger/DisplayDevice.h
index cb8fe2f..0229dad 100644
--- a/services/surfaceflinger/DisplayDevice.h
+++ b/services/surfaceflinger/DisplayDevice.h
@@ -51,7 +51,8 @@
 
     enum {
         DISPLAY_ID_MAIN = 0,
-        DISPLAY_ID_HDMI = 1
+        DISPLAY_ID_HDMI = 1,
+        DISPLAY_ID_COUNT
     };
 
     enum {