[0/4] Add "activ bpc" drm property and use it in AMD and Intel driver

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Werner Sembach June 4, 2021, 5:17 p.m. UTC

I started work on my proposal for better color handling in Linux display
drivers: https://lkml.org/lkml/2021/5/12/764

Since the first read-only property is now implemented for amdgpu and i915 I
wanted to collect some feedback, since the other two read-only properties will
be quite similar, I hope.

I have already commited the first patch in this series independently as it fixes
a function already in use.

The actuall update of the values is implemented in patch three and four in the
atomic_commit_tail() function of amdgpu and i915 respectifly. It does get
updated more often than needed with the current approach, but without harm since
just the same value is written again. A check if the update is required would be
the same amount of computation. Let me know if you know a better place to put
the update than attomic_commit_tail().