[Intel-gfx] [PATCH] drm/i915: Use intel_panel_actually_set_backlight() to disable PWM backlight

[Chris Wilson]

Quoting Ville Syrjälä (2018-10-24 17:33:17)
> On Wed, Oct 24, 2018 at 05:02:18PM +0100, Chris Wilson wrote:
> > Quoting Ville Syrjala (2018-10-24 16:52:08)
> > > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > 
> > > Use intel_panel_actually_set_backlight() instead of a direct
> > > call to pwm_config() in pwm_disable_backlight().
> > > 
> > > The main benefit is consistent debug logging when we turn off the
> > > backlight. Currently we see nothing in dmesg which made me wonder
> > > whether the backlight was even getting turned off properly.
> > > 
> > > The second benefit is consistency; This is what we do for all
> > > the other backlight implementations.
> > 
> > It will also have the effect of calling
> > intel_panel_compute_brightness(0) which one presumes is desired?
> 
> We do it for everything else so it must be good?
> 
> > 
> > Just worrying if the inverted brightness quirk is ever used with pwm.
> 
> If we have to invert for normal operation I don't know why
> we wouldn't want to invert when shutting down the backlight.

Neither do I, just seems weird to set pwm to full to turn it off.

Whatever, the disparity is silly,
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris