diff --git a/src/mesa/state_tracker/st_public.h b/src/mesa/state_tracker/st_public.h
index a5fdac32d1f..2f25b8b5737 100644
--- a/src/mesa/state_tracker/st_public.h
+++ b/src/mesa/state_tracker/st_public.h
@@ -39,7 +39,7 @@
 #define ST_SURFACE_BACK_LEFT    1
 #define ST_SURFACE_FRONT_RIGHT  2
 #define ST_SURFACE_BACK_RIGHT   3
-#define ST_SURFACE_DEPTH        8
+#define ST_SURFACE_DEPTH        4
 
 #define ST_TEXTURE_2D    0x2
 #define ST_TEXTURE_RECT  0x4