diff --git a/drivers/net/dm9000x.c b/drivers/net/dm9000x.c
index 137e41fef5..709f67aac2 100644
--- a/drivers/net/dm9000x.c
+++ b/drivers/net/dm9000x.c
@@ -117,12 +117,12 @@ static void DM9000_iow(int reg, u8 value);
 
 /* DM9000 network board routine ---------------------------- */
 
-#define DM9000_outb(d,r) writeb(d, r)
-#define DM9000_outw(d,r) writew(d, r)
-#define DM9000_outl(d,r) writel(d, r)
-#define DM9000_inb(r) readb(r)
-#define DM9000_inw(r) readw(r)
-#define DM9000_inl(r) readl(r)
+#define DM9000_outb(d,r) writeb(d, (volatile u8 *)(r))
+#define DM9000_outw(d,r) writew(d, (volatile u16 *)(r))
+#define DM9000_outl(d,r) writel(d, (volatile u32 *)(r))
+#define DM9000_inb(r) readb((volatile u8 *)(r))
+#define DM9000_inw(r) readw((volatile u16 *)(r))
+#define DM9000_inl(r) readl((volatile u32 *)(r))
 
 #ifdef CONFIG_DM9000_DEBUG
 static void