diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 1f27a70..0080202 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -93,6 +93,7 @@
         mDebugBackground(0),
         mDebugDDMS(0),
         mDebugDisableHWC(0),
+        mDebugDisableTransformHint(0),
         mDebugInSwapBuffers(0),
         mLastSwapBufferTime(0),
         mDebugInTransaction(0),
@@ -1689,6 +1690,12 @@
                 invalidateHwcGeometry();
                 repaintEverything();
                 return NO_ERROR;
+            case 1009:  // toggle use of transform hint
+                n = data.readInt32();
+                mDebugDisableTransformHint = n ? 1 : 0;
+                invalidateHwcGeometry();
+                repaintEverything();
+                return NO_ERROR;
             case 1010:  // interrogate.
                 reply->writeInt32(0);
                 reply->writeInt32(0);