diff --git a/arch/h8300/include/asm/io.h b/arch/h8300/include/asm/io.h
index f0e14f3a800d..2e221c5f0203 100644
--- a/arch/h8300/include/asm/io.h
+++ b/arch/h8300/include/asm/io.h
@@ -44,17 +44,17 @@ static inline void __raw_writel(u32 b, const volatile void __iomem *addr)
 static inline void ctrl_bclr(int b, void __iomem *addr)
 {
 	if (__builtin_constant_p(b))
-		__asm__("bclr %1,%0" : "+WU"(*addr): "i"(b));
+		__asm__("bclr %1,%0" : "+WU"(*(u8 *)addr): "i"(b));
 	else
-		__asm__("bclr %w1,%0" : "+WU"(*addr): "r"(b));
+		__asm__("bclr %w1,%0" : "+WU"(*(u8 *)addr): "r"(b));
 }
 
 static inline void ctrl_bset(int b, void __iomem *addr)
 {
 	if (__builtin_constant_p(b))
-		__asm__("bset %1,%0" : "+WU"(*addr): "i"(b));
+		__asm__("bset %1,%0" : "+WU"(*(u8 *)addr): "i"(b));
 	else
-		__asm__("bset %w1,%0" : "+WU"(*addr): "r"(b));
+		__asm__("bset %w1,%0" : "+WU"(*(u8 *)addr): "r"(b));
 }
 
 #include <asm-generic/io.h>