diff --git a/include/hardware/gralloc.h b/include/hardware/gralloc.h
index d50c895..73cc9e0 100644
--- a/include/hardware/gralloc.h
+++ b/include/hardware/gralloc.h
@@ -64,11 +64,18 @@
     /* buffer will be used as an OpenGL ES render target */
     GRALLOC_USAGE_HW_RENDER       = 0x00000200,
     /* buffer will be used by the 2D hardware blitter */
-    GRALLOC_USAGE_HW_2D           = 0x00000C00,
+    GRALLOC_USAGE_HW_2D           = 0x00000400,
     /* buffer will be used with the framebuffer device */
     GRALLOC_USAGE_HW_FB           = 0x00001000,
     /* mask for the software usage bit-mask */
     GRALLOC_USAGE_HW_MASK         = 0x00001F00,
+
+    /* implementation-specific private usage flags */
+    GRALLOC_USAGE_PRIVATE_0       = 0x10000000,
+    GRALLOC_USAGE_PRIVATE_1       = 0x20000000,
+    GRALLOC_USAGE_PRIVATE_2       = 0x40000000,
+    GRALLOC_USAGE_PRIVATE_3       = 0x80000000,
+    GRALLOC_USAGE_PRIVATE_MASK    = 0xF0000000,
 };
 
 /*****************************************************************************/