> -----Original Message----- > From: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> > Sent: Thursday, April 4, 2024 2:34 PM > To: Kandpal, Suraj <suraj.kandpal@xxxxxxxxx>; intel-gfx@xxxxxxxxxxxxxxxxxxxxx > Cc: Borah, Chaitanya Kumar <chaitanya.kumar.borah@xxxxxxxxx>; Shankar, > Uma <uma.shankar@xxxxxxxxx>; Nautiyal, Ankit K > <ankit.k.nautiyal@xxxxxxxxx>; Murthy, Arun R <arun.r.murthy@xxxxxxxxx>; > Syrjala, Ville <ville.syrjala@xxxxxxxxx>; Kumar, Naveen1 > <naveen1.kumar@xxxxxxxxx>; sebastian.wick@xxxxxxxxxx; Kandpal, Suraj > <suraj.kandpal@xxxxxxxxx> > Subject: Re: [PATCH 7/7] drm/i915/dp: Limit brightness level to 20 > > On Thu, 04 Apr 2024, Suraj Kandpal <suraj.kandpal@xxxxxxxxx> wrote: > > Limit minimum brightness to 20 when using aux based brightness control > > to avoid letting the screen going completely blank. > > Why "20"? What does it mean? Why don't we have this in the VBT like for > PWM backlight? That makes sense. I used 20nits as that's where I felt the minimum amount of brightness looked okay. But yes I could use the minimum brightness that we save in intel_panel ->backlight structure Regards, Suraj Kandpal > > > > > Signed-off-by: Suraj Kandpal <suraj.kandpal@xxxxxxxxx> > > --- > > drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 3 +++ > > 1 file changed, 3 insertions(+) > > > > diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > > b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > > index 20dd5a6a0f3f..b54ea7e46954 100644 > > --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > > +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > > @@ -211,6 +211,9 @@ intel_dp_aux_hdr_set_aux_backlight(const struct > drm_connector_state *conn_state, > > struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); > > u8 buf[4] = {}; > > > > + if (level < 20) > > + level = 20; > > + > > buf[0] = level & 0xFF; > > buf[1] = (level & 0xFF00) >> 8; > > -- > Jani Nikula, Intel