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Subject: Re: [PATCH v2] drm/color: Document CTM eqations
To: Brian Starkey <brian.starkey@arm.com>,
        Daniel Stone <daniel@fooishbar.org>
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From: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Organization: Intel Corporation (UK) Ltd. - Co. Reg. #1134945 - Pipers Way,
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On 17/02/17 13:54, Brian Starkey wrote:
> What's the verdict? We've got [1] which is about to become another
> (driver) implementation - better to change before that merges than
> after I guess.
>
> -Brian
>
> [1] https://lkml.org/lkml/2017/2/13/304
>
> On Wed, Feb 15, 2017 at 11:56:55AM +0000, Daniel Stone wrote:
>> Hi,
>>
>> On 15 February 2017 at 11:39, Ville Syrjälä
>> <ville.syrjala@linux.intel.com> wrote:
>>> On Tue, Jan 31, 2017 at 06:46:39PM +0100, Daniel Vetter wrote:
>>>> On Tue, Jan 31, 2017 at 6:22 PM, Ville Syrjälä
>>>> <ville.syrjala@linux.intel.com> wrote:
>>>> > Hmm. Two's complement is what I was thinking it is. Which shows that
>>>> > I never managed to read the code in any detail. Definitely needs to
>>>> > be documented properly.
>>>>
>>>> That sounds supremely backwards. I guess we can't fix this anymore?
>>>
>>> I have no idea. Anyone else?
>>
>> I don't know of any implementation using this; maybe closed Intel
>> Android stuff? Certainly GitHub showed no-one using it, and neither X
>> nor Weston/Mutter are using it yet.
>>
>> Cheers,
>> Daniel
>
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

-
Lionel