diff --git a/sys/arch/zaurus/dev/w100.c b/sys/arch/zaurus/dev/w100.c
index 8cd9791ea721..294668a0d6ff 100644
--- a/sys/arch/zaurus/dev/w100.c
+++ b/sys/arch/zaurus/dev/w100.c
@@ -1,4 +1,4 @@
-/* $NetBSD: w100.c,v 1.3 2020/11/21 17:22:03 thorpej Exp $ */
+/* $NetBSD: w100.c,v 1.4 2021/11/20 00:17:10 rin Exp $ */
 /*
  * Copyright (c) 2002, 2003  Genetec Corporation.  All rights reserved.
  * Written by Hiroyuki Bessho for Genetec Corporation.
@@ -28,7 +28,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: w100.c,v 1.3 2020/11/21 17:22:03 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: w100.c,v 1.4 2021/11/20 00:17:10 rin Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -257,7 +257,7 @@ w100_setup_rasops(struct w100_softc *sc, struct rasops_info *rinfo,
     struct w100_wsscreen_descr *descr, const struct w100_panel_geometry *geom)
 {
 
-	rinfo->ri_flg = descr->flags;
+	rinfo->ri_flg = descr->flags | RI_CLEAR | RI_ENABLE_ALPHA;
 	rinfo->ri_depth = descr->depth;
 	rinfo->ri_width = sc->display_width;
 	rinfo->ri_height = sc->display_height;