Signed-off-by: Atsushi Nemoto <anemo@xxxxxxxxxxxxx>
diff --git a/include/asm-mips/io.h b/include/asm-mips/io.h
index c16d54f..0ec40f9 100644
--- a/include/asm-mips/io.h
+++ b/include/asm-mips/io.h
@@ -342,7 +342,7 @@ static inline void pfx##write##bwlq(type
BUG(); \
} \
\
-static inline type pfx##read##bwlq(volatile void __iomem *mem) \
+static inline type pfx##read##bwlq(const volatile void __iomem *mem) \
{ \
volatile type *__mem; \
type __val; \
