7 #define bcd2bin(x)					\  argument
8 		(__builtin_constant_p((u8 )(x)) ?	\
9 		const_bcd2bin(x) :			\
10 		_bcd2bin(x))
12 #define bin2bcd(x)					\  argument
13 		(__builtin_constant_p((u8 )(x)) ?	\
14 		const_bin2bcd(x) :			\
15 		_bin2bcd(x))
17 #define bcd_is_valid(x)					\  argument
18 		const_bcd_is_valid(x)
20 #define const_bcd2bin(x)	(((x) & 0x0f) + ((x) >> 4) * 10)  argument
21 #define const_bin2bcd(x)	((((x) / 10) << 4) + (x) % 10)  argument
22 #define const_bcd_is_valid(x)	(((x) & 0x0f) < 10 && ((x) >> 4) < 10)  argument