diff --git a/drivers/video/acornfb.c b/drivers/video/acornfb.c
index eedb828..017233d 100644
--- a/drivers/video/acornfb.c
+++ b/drivers/video/acornfb.c
@@ -23,6 +23,7 @@
 #include <linux/string.h>
 #include <linux/ctype.h>
 #include <linux/slab.h>
+#include <linux/mm.h>
 #include <linux/init.h>
 #include <linux/fb.h>
 #include <linux/platform_device.h>