include/linux/bcd.h

root/include/linux/bcd.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _BCD_H
#define _BCD_H

#include <linux/compiler.h>

#define bcd2bin(x)                                      \
                (__builtin_constant_p((u8 )(x)) ?       \
                const_bcd2bin(x) :                      \
                _bcd2bin(x))

#define bin2bcd(x)                                      \
                (__builtin_constant_p((u8 )(x)) ?       \
                const_bin2bcd(x) :                      \
                _bin2bcd(x))

#define bcd_is_valid(x)                                 \
                const_bcd_is_valid(x)

#define const_bcd2bin(x)        (((x) & 0x0f) + ((x) >> 4) * 10)
#define const_bin2bcd(x)        ((((x) / 10) << 4) + (x) % 10)
#define const_bcd_is_valid(x)   (((x) & 0x0f) < 10 && ((x) >> 4) < 10)

unsigned _bcd2bin(unsigned char val) __attribute_const__;
unsigned char _bin2bcd(unsigned val) __attribute_const__;

#endif /* _BCD_H */
Linux
