diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h
index 912088773a69ef55b5313d7a6ccd5acebbc1de36..c2cf2eda062635f56c982547bd87c2796ad62a44 100644
--- a/include/asm-generic/io.h
+++ b/include/asm-generic/io.h
@@ -327,7 +327,7 @@ static inline void __iomem *ioremap(phys_addr_t offset, unsigned long size)
 #define ioremap_wc ioremap_nocache
 #endif
 
-static inline void iounmap(void *addr)
+static inline void iounmap(void __iomem *addr)
 {
 }
 #endif /* CONFIG_MMU */