diff --git a/graphics/common/1.0/types.hal b/graphics/common/1.0/types.hal
index 67ff353..e20fedc 100644
--- a/graphics/common/1.0/types.hal
+++ b/graphics/common/1.0/types.hal
@@ -39,9 +39,11 @@
 
     /*
      * The following formats use a 16bit float per color component.
+     *
+     * When used with ANativeWindow, the dataSpace field describes the color
+     * space of the buffer.
      */
     RGBA_FP16          = 0x16,
-    RGBX_FP16          = 0x17,
 
     /*
      * 0x101 - 0x1FF