diff --git a/src/sys/include/sys/device.h b/src/sys/include/sys/device.h
index 7389c4c..fd1ec6a 100644
--- a/src/sys/include/sys/device.h
+++ b/src/sys/include/sys/device.h
@@ -33,8 +33,8 @@
   int major;
   int minor;
   uInt32 size;
-  void (*read)(void *,long,long,void *);
-  void (*write)(void *,long,long,void *);
+  void (*read)(void *,void *,uInt32,uInt32);
+  void (*write)(void *,void *,uInt32,uInt32);
   void (*reset)(void *);
   void (*init)(void *);
   void (*ioctl)(void *);