[PATCH 03/13] drm/dp: Add argument for luminance range info in drm_edp_backlight_init

[Murthy, Arun R]

> > > -----Original Message-----
> > > From: Kandpal, Suraj <suraj.kandpal at intel.com>
> > > Sent: Monday, April 14, 2025 9:46 AM
> > > To: nouveau at lists.freedesktop.org; dri-devel at lists.freedesktop.org;
> > > intel- xe at lists.freedesktop.org; intel-gfx at lists.freedesktop.org
> > > Cc: Nautiyal, Ankit K <ankit.k.nautiyal at intel.com>; Murthy, Arun R
> > > <arun.r.murthy at intel.com>; Kandpal, Suraj <suraj.kandpal at intel.com>
> > > Subject: [PATCH 03/13] drm/dp: Add argument for luminance range info
> > > in drm_edp_backlight_init
> > >
> > > Add new argument to drm_edp_backlight_init which gives the
> > > drm_luminance_range_info struct which will be needed to set the min
> > > and max values for backlight.
> > >
> > > Signed-off-by: Suraj Kandpal <suraj.kandpal at intel.com>
> > > ---
> > >  drivers/gpu/drm/display/drm_dp_helper.c               | 5 ++++-
> > >  drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c | 5 +++--
> > >  drivers/gpu/drm/nouveau/nouveau_backlight.c           | 5 ++++-
> > >  include/drm/display/drm_dp_helper.h                   | 1 +
> > >  4 files changed, 12 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/display/drm_dp_helper.c
> > > b/drivers/gpu/drm/display/drm_dp_helper.c
> > > index 99b27e5e3365..3b309ac5190b 100644
> > > --- a/drivers/gpu/drm/display/drm_dp_helper.c
> > > +++ b/drivers/gpu/drm/display/drm_dp_helper.c
> > > @@ -4227,6 +4227,8 @@ drm_edp_backlight_probe_state(struct
> > drm_dp_aux
> > > *aux, struct drm_edp_backlight_i
> > >   * interface.
> > >   * @aux: The DP aux device to use for probing
> > >   * @bl: The &drm_edp_backlight_info struct to fill out with
> > > information on the backlight
> > > + * @lr: The &drm_luminance_range_info struct which is used to get
> > > + the min max when using *luminance override
> > >   * @driver_pwm_freq_hz: Optional PWM frequency from the driver in hz
> > >   * @edp_dpcd: A cached copy of the eDP DPCD
> > >   * @current_level: Where to store the probed brightness level, if
> > > any @@ -
> > > 4243,6 +4245,7 @@ drm_edp_backlight_probe_state(struct drm_dp_aux
> > > *aux, struct drm_edp_backlight_i
> > >   */
> > >  int
> > >  drm_edp_backlight_init(struct drm_dp_aux *aux, struct
> > > drm_edp_backlight_info *bl,
> > > +		       struct drm_luminance_range_info *lr,
> > Would it be better to have this drm_luminance_range_info inside the
> > drm_edp_backlight_info?
> 
> The thing is we fill drm_edp_backlight_info struct in drm_edp_backlight_init
> Which means we would have to pass it anyways. So having a reference of this in
> drm_edp_backlight_info didn't make sense.
> 
The main intention for this ask is two xx_info struct passed as argument.
Moreover luminance is part of backlight and this new element is _info and there already exists backlight_info. So wondering is luminance can be put inside backlight_info. The caller of this function can fill the luminance part and then make a call.

Thanks and Regards,
Arun R Murthy
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