mhz19b_serdev_cmd
ret = mhz19b_serdev_cmd(indio_dev, MHZ19B_READ_CO2_CMD, 0);
ret = mhz19b_serdev_cmd(indio_dev, MHZ19B_ABC_LOGIC_CMD, enable);
ret = mhz19b_serdev_cmd(indio_dev, cmd, ppm);