diff --git a/f32x/gpio-s3c24xx.c b/f32x/gpio-s3c24xx.c
index b58ed86..34cce5e 100644
--- a/f32x/gpio-s3c24xx.c
+++ b/f32x/gpio-s3c24xx.c
@@ -1,8 +1,8 @@
 /*
  * f32x/gpio-s3c24xx.c - Really primitive S3C244x GPIO access. Ports B-H only.
  *
- * Written 2008 by Werner Almesberger
- * Copyright 2008 Werner Almesberger
+ * Written 2008, 2011 by Werner Almesberger
+ * Copyright 2008, 2011 Werner Almesberger
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -29,7 +29,7 @@ void gpio_init(void)
 {
 	int fd;
 
-	fd = open("/dev/mem", O_RDWR);
+	fd = open("/dev/mem", O_RDWR | O_SYNC);
         if (fd < 0) {
 		perror("/dev/mem");
 		exit(1);
diff --git a/f32x/gpio-xburst.c b/f32x/gpio-xburst.c
index 0b0e12e..dbec481 100644
--- a/f32x/gpio-xburst.c
+++ b/f32x/gpio-xburst.c
@@ -1,8 +1,8 @@
 /*
  * f32x/gpio-xburst.c - Really primitive XBurst GPIO access
  *
- * Written 2010 by Werner Almesberger
- * Copyright 2010 Werner Almesberger
+ * Written 2010-2011 by Werner Almesberger
+ * Copyright 2010-2011 Werner Almesberger
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -29,7 +29,7 @@ void gpio_init(void)
 {
 	int fd;
 
-	fd = open("/dev/mem", O_RDWR);
+	fd = open("/dev/mem", O_RDWR | O_SYNC);
         if (fd < 0) {
 		perror("/dev/mem");
 		exit(1);