diff --git a/arch/m68k/include/asm/io_no.h b/arch/m68k/include/asm/io_no.h
index ccb8c31faf49..83a0a6d449f4 100644
--- a/arch/m68k/include/asm/io_no.h
+++ b/arch/m68k/include/asm/io_no.h
@@ -2,6 +2,12 @@
 #ifndef _M68KNOMMU_IO_H
 #define _M68KNOMMU_IO_H
 
+/*
+ * Convert a physical memory address into a IO memory address.
+ * For us this is trivially a type cast.
+ */
+#define iomem(a)	((void __iomem *) (a))
+
 /*
  * The non-MMU m68k and ColdFire IO and memory mapped hardware access
  * functions have always worked in CPU native endian. We need to define