diff --git a/include/asm-avr32/io.h b/include/asm-avr32/io.h
index e30d4b3bd836..64bb92bb6773 100644
--- a/include/asm-avr32/io.h
+++ b/include/asm-avr32/io.h
@@ -255,6 +255,8 @@ static inline void memset_io(volatile void __iomem *addr, unsigned char val,
 	memset((void __force *)addr, val, count);
 }
 
+#define mmiowb()
+
 #define IO_SPACE_LIMIT	0xffffffff
 
 extern void __iomem *__ioremap(unsigned long offset, size_t size,