On Wed, 31 Jul 2019, Peter Ujfalusi wrote: > The default-on property - or the def_value via legacy pdata) should be > handled as: > if it is 1, the backlight must be enabled (kept enabled) > if it is 0, the backlight must be disabled (kept disabled) > > This only works for the case when default-on is set. If it is not set then > the brightness of the backlight is set to 0. Now if the backlight is > enabled by external driver (graphics) the backlight will stay disabled since > the brightness is configured as 0. The backlight will not turn on. > > In order to minimize screen flickering during device boot: > > The initial brightness should be set to 1. > > If booted in non DT mode or no phandle link to the backlight node: > follow the def_value/default-on to select UNBLANK or POWERDOWN > > If in DT boot we have phandle link then leave the GPIO in a state which the > bootloader left it and let the user of the backlight to configure it > further. > > Signed-off-by: Peter Ujfalusi <peter.ujfalusi@xxxxxx> > --- > Hi, > > sorry for the delay, but got distracted a bit with the resend of this... > Let's try again ;) > > Changes since v2 (https://lore.kernel.org/patchwork/patch/1002359/): > - Rebased on drm-next > > Changes since v1: > - Implement similiar initial power state handling as pwm backlight have > > Regards, > Peter > > drivers/video/backlight/gpio_backlight.c | 24 ++++++++++++++++++++---- > 1 file changed, 20 insertions(+), 4 deletions(-) Applied, thanks. -- Lee Jones [李琼斯] Linaro Services Technical Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
