diff --git a/include/system/window.h b/include/system/window.h
index 56c3da6..15a9a55 100644
--- a/include/system/window.h
+++ b/include/system/window.h
@@ -355,7 +355,8 @@
     NATIVE_WINDOW_SET_AUTO_REFRESH          = 22,
     NATIVE_WINDOW_ENABLE_FRAME_TIMESTAMPS   = 23,
     NATIVE_WINDOW_GET_FRAME_TIMESTAMPS      = 24,
-    NATIVE_WINDOW_GET_REFRESH_CYCLE_PERIOD  = 25,
+    NATIVE_WINDOW_GET_REFRESH_CYCLE_DURATION= 25,
+    NATIVE_WINDOW_GET_REFRESH_CYCLE_PERIOD  = 26,
 };
 
 /* parameter for NATIVE_WINDOW_[API_][DIS]CONNECT */
@@ -1040,6 +1041,14 @@
             outDisplayRetireTime, outDequeueReadyTime, outReleaseTime);
 }
 
+static inline int native_window_get_refresh_cycle_duration(
+        struct ANativeWindow* window,
+        int64_t* outRefreshDuration)
+{
+    return window->perform(window, NATIVE_WINDOW_GET_REFRESH_CYCLE_DURATION,
+            outRefreshDuration);
+}
+
 static inline int native_window_get_refresh_cycle_period(
         struct ANativeWindow* window,
         int64_t* outMinRefreshDuration, int64_t* outMaxRefreshDuration)