voyager_write_gpio
voyager_write_gpio(sc, 0xffffffff, 1 << 16);
voyager_write_gpio(sc->sc_gpio_cookie, 0xffffffff, GPIO_BACKLIGHT);
voyager_write_gpio(sc->sc_gpio_cookie,
voyager_write_gpio(sc->sc_gpio_cookie,
voyager_write_gpio(sc->sc_gpio_cookie, ~GPIO_BACKLIGHT, 0);