RK3308BS_DAC_DIG_GAIN_SFT
#define RK3308BS_DAC_DIG_GAIN_MSK (0xff << RK3308BS_DAC_DIG_GAIN_SFT)
#define RK3308BS_DAC_DIG_GAIN_0DB (0xed << RK3308BS_DAC_DIG_GAIN_SFT)