diff --git a/drivers/usb/input/wacom_wac.h b/drivers/usb/input/wacom_wac.h
index a230222..8979366 100644
--- a/drivers/usb/input/wacom_wac.h
+++ b/drivers/usb/input/wacom_wac.h
@@ -39,7 +39,7 @@
 };
 
 struct wacom_wac {
-	signed char *data;
+	unsigned char *data;
         int tool[2];
         int id[2];
         __u32 serial[2];