Hi All First at all I introduce my usecase -My board based on ARM (OMPA4) can get a custom splash screen on booting using fbcon. -By Device Tree I can configure screen backlight with desired level. i'm trying to turn on backlight when splash screen is displayed and not before to avoid "white flashes". I read Documentation/devicetree/bindings/pwm/pwm.txt Documentation/devicetree/bindings/leds/pwm-backlight.txt Documentation/fb/... https://www.kernel.org/doc/html/v4.14/admin-guide/kernel-parameters.html Also I noticed that pwm_bl has pwm_backlight_check_fb operation, but I didnt find a clear way to relate frame buffer used by fbcon with pwm_bl related functions or how to customize by DT or kernel config which frame buffer should be used by pwm_bl to turn on when valid data is ready in fb Any hints will be apreciated. Regards