Re: [PATCH v2] drm/color: Document CTM eqations

[Daniel Stone]

Hi,

On 17 February 2017 at 14:56, Ville SyrjÃlÃ
<ville.syrjala@xxxxxxxxxxxxxxx> wrote:
> On Fri, Feb 17, 2017 at 02:42:26PM +0000, Lionel Landwerlin wrote:
>> If we're talking fixed point reprsentation, ChromeOS is using this :
>>
>> https://cs.chromium.org/chromium/src/ui/ozone/platform/drm/gpu/drm_device.cc?q=DrmDevice&l=209
>
> So it's already using the sign+magnitude stuff. Which presumably
> means we can't change it to two's complement anymore :( Maybe we add a
> CTM2 property ;)

I wouldn't be so sure; AFAIK it only ships on platforms where the
kernel is also built from the same tree, and generally where the
support is backported anyway. So it would be possible to atomically
land a change to CrOS such that the kernels and Chrome move together
to a changed representation.

Cheers,
Daniel