[PATCH v4 2/5] drm/drm_property: require DRM_MODE_PROP_IMMUTABLE for single-value props

[Dmitry Baryshkov]

On Wed, Jul 17, 2024 at 03:42:46PM GMT, Maxime Ripard wrote:
> Hi,
> 
> On Mon, Jul 15, 2024 at 09:33:02AM GMT, Dmitry Baryshkov wrote:
> > Document that DRM_MODE_PROP_IMMUTABLE must be set for the properties
> > that are immutable by definition - e.g. ranges with min == max or enums
> > with a single value. This matches the behaviour of the IGT tests, see
> > kms_properties.c / validate_range_prop(), validate_enum_prop(),
> > validate_bitmask_prop().
> > 
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
> 
> We had a discussion yesterday about it on IRC with Sima, Simon and
> Xaver.
> 
> https://oftc.irclog.whitequark.org/dri-devel/2024-07-16#33374622;
> 
> The conclusion was that it would create an inconsistency between drivers
> on whether a given property is immutable or not, which will lead to more
> troubles for userspace.
> 
> It's not clear why Ville added that check in the first place, so the
> best course of action is to remove the IGT test and get the discussion
> started there.

Ack, I'll work on removing those tests later today.

-- 
With best wishes
Dmitry