config_sub_second_increment
void (*config_sub_second_increment)(void __iomem *ioaddr, u32 ptp_clock,
stmmac_do_void_callback(__priv, ptp, config_sub_second_increment, __args)
.config_sub_second_increment = config_sub_second_increment,
.config_sub_second_increment = config_sub_second_increment,