base/regmap/regmap.c

821 		if (config->reg_update_bits)
822 			map->reg_update_bits = config->reg_update_bits;
833 		map->reg_update_bits = config->reg_update_bits;
840 		map->reg_update_bits = bus->reg_update_bits;
846 		map->reg_update_bits = bus->reg_update_bits;
3186 	if (regmap_volatile(map, reg) && map->reg_update_bits) {
3188 		ret = map->reg_update_bits(map->bus_context, reg, mask, val);