Hi Paul, On Mon, Jul 03, 2023 at 11:47:14PM +0200, Paul Cercueil wrote: > Register a backlight device to be able to switch between all the gamma > levels. > > Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> > --- > drivers/gpu/drm/panel/panel-samsung-ld9040.c | 40 ++++++++++++++++++++ > 1 file changed, 40 insertions(+) > > diff --git a/drivers/gpu/drm/panel/panel-samsung-ld9040.c b/drivers/gpu/drm/panel/panel-samsung-ld9040.c > index 7fd9444b42c5..b4f87d6244cb 100644 > --- a/drivers/gpu/drm/panel/panel-samsung-ld9040.c > +++ b/drivers/gpu/drm/panel/panel-samsung-ld9040.c > @@ -8,6 +8,7 @@ > * Andrzej Hajda <a.hajda@xxxxxxxxxxx> > */ > > +#include <linux/backlight.h> > #include <linux/delay.h> > #include <linux/gpio/consumer.h> > #include <linux/module.h> > @@ -311,8 +312,40 @@ static int ld9040_parse_dt(struct ld9040 *ctx) > return 0; > } > > +static int ld9040_bl_update_status(struct backlight_device *dev) > +{ > + struct ld9040 *ctx = dev_get_drvdata(&dev->dev); There is also the helper bl_get_data() - that do the same. Sam