Hi Hpilipp, On Thu, 2015-10-29 at 16:40 +0100, Philipp Zabel wrote: > Hi YH, > > Am Donnerstag, den 22.10.2015, 23:12 +0800 schrieb YH Huang: > > In the case of the panel disabled by the bootloader, > > your patch still has the following code and always enables the backlight > > in the probe function. > > pb->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable", > > - GPIOD_OUT_HIGH); > > You are right. > > > What do you think if I remove these two lines in my patch? > > if (pb->enable_gpio) > > gpiod_direction_output(pb->enable_gpio, 0); > > That won't work if the gpio is still configured as input. How about I > add the GPIOD_ASIS change to my patch you remove that and the above from > yours? I revise these two lines if (pb->enable_gpio) gpiod_direction_output(pb->enable_gpio, 0); into if (pb->enable_gpio) { if(gpiod_get_value(pb->enable_gpio) == 0) gpiod_direction_output(pb->enable_gpio, 0); else gpiod_direction_output(pb->enable_gpio, 1); } I am not sure what "phandle" is working for. My change is like your patch but remove the "phandle related" and "gpiod_get_direction(pb->enable_gpio) == GPIOF_DIR_OUT". Do we really need these? Also, do you think it is right that I do the "pwm_enable(pb->pwm);" before "gpiod_set_value(pb->enable_gpio, 1);" in power on function? Regards, YH Huang -- To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html