HDCS_REG_CONTROL
ret = stv06xx_write_sensor(sd, HDCS_REG_CONTROL(sd), 0);
ret = stv06xx_write_sensor(sd, HDCS_REG_CONTROL(sd), val);
err = stv06xx_write_sensor(sd, HDCS_REG_CONTROL(sd), 1);
err = stv06xx_write_sensor(sd, HDCS_REG_CONTROL(sd), 0);