Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/commits/commit/f5fdc3785d4beb179d2249bf1a886f679f925774/drivers/video/pwm_backlight.c
You should set ROOT_URL correctly, otherwise the web may not work correctly.
Many backlights need to use a PWM to control the brightness. Add a driver
for this. It understands the standard device tree binding.
Signed-off-by: Simon Glass <sjg@chromium.org>