[Intel-gfx] [v6 0/2] Add Colorspace connector property interface

[Shankar, Uma]

>-----Original Message-----
>From: Brian Starkey [mailto:Brian.Starkey at arm.com]
>Sent: Tuesday, January 8, 2019 7:37 PM
>To: Shankar, Uma <uma.shankar at intel.com>
>Cc: intel-gfx at lists.freedesktop.org; dri-devel at lists.freedesktop.org; Lankhorst,
>Maarten <maarten.lankhorst at intel.com>; Syrjala, Ville <ville.syrjala at intel.com>;
>Sharma, Shashank <shashank.sharma at intel.com>; nd <nd at arm.com>
>Subject: Re: [v6 0/2] Add Colorspace connector property interface
>
>Hi Uma,
>
>On Thu, Dec 27, 2018 at 11:22:36PM +0530, Uma Shankar wrote:
>> This patch series creates a new connector property to program
>> colorspace to sink devices. Modern sink devices support more than 1
>> type of colorspace like 601, 709, BT2020 etc. This helps to switch
>> based on content type which is to be displayed. The decision lies with
>> compositors as to in which scenarios, a particular colorspace will be
>> picked.
>>
>> This will be helpful mostly to switch to higher gamut colorspaces like
>> BT2020 when the media content is encoded as BT2020. Thereby giving a
>> good visual experience to users.
>>
>> The expectation from userspace is that it should parse the EDID and
>> get supported colorspaces. Use this property and switch to the one
>> supported. Kernel will not give the supported colorspaces since this
>> is panel dependent and our current property infrastructure is not
>> supporting it.
>>
>> Basically the expectation from userspace is:
>>  - Set up CRTC DEGAMMA/CTM/GAMMA to convert to some sink
>>    colorspace
>>  - Set this new property to let the sink know what it
>>    converted the CRTC output to.
>>  - This property is just to inform sink what colorspace
>>    source is trying to drive.
>
>All the above info is really important/useful stuff, but it's going to get lost
>because it's only in the cover letter. This should either find its way into the
>commit message of patch 1 or even better, into the kerneldoc for the property.

Sure Brian, Will add it to kernel doc as well to commit message so that it's not lost.

Regards,
Uma Shankar

>Cheers,
>-Brian
>
>>
>> Have tested this using xrandr by using below command:
>> xrandr --output HDMI2 --set "Colorspace" "BT2020_rgb"
>>
>> v2: Addressed Ville and Maarten's review comments. Merged the 2nd and
>> 3rd patch into one common logical patch.
>>
>> v3: Removed Adobe references from enum definitions as per Ville, Hans
>> Verkuil and Jonas Karlman suggestions. Changed default to an unset
>> state where driver will assign the colorspace when not chosen by user,
>> suggested by Ville and Maarten. Addressed other misc review comments
>> from Maarten. Split the changes to have separate colorspace property
>> for DP and HDMI.
>>
>> v4: Addressed Chris and Ville's review comments, and created a common
>> colorspace property for DP and HDMI, filtered the list based on the
>> colorspaces supported by the respective protocol standard. Handled the
>> default case more efficiently.
>>
>> v5: Modified the colorspace property creation helper to take platform
>> specific enum list based on the capabilities of the platform as
>> suggested by Shashank. With this there is no need for segregation
>> between DP and HDMI.
>>
>> v6: Addressed Shashank's review comments.
>>
>> Uma Shankar (2):
>>   drm: Add colorspace connector property
>>   drm/i915: Attach colorspace property and enable modeset
>>
>>  drivers/gpu/drm/drm_atomic_uapi.c      |  4 ++
>>  drivers/gpu/drm/drm_connector.c        | 82
>++++++++++++++++++++++++++++++++++
>>  drivers/gpu/drm/i915/intel_atomic.c    |  1 +
>>  drivers/gpu/drm/i915/intel_connector.c | 63 ++++++++++++++++++++++++++
>>  drivers/gpu/drm/i915/intel_drv.h       |  1 +
>>  drivers/gpu/drm/i915/intel_hdmi.c      | 18 ++++++++
>>  include/drm/drm_connector.h            | 17 +++++++
>>  include/uapi/drm/drm_mode.h            | 33 ++++++++++++++
>>  8 files changed, 219 insertions(+)
>>
>> --
>> 1.9.1
>>
>> Uma Shankar (2):
>>   drm: Add colorspace connector property
>>   drm/i915: Attach colorspace property and enable modeset
>>
>>  drivers/gpu/drm/drm_atomic_uapi.c      |  4 ++
>>  drivers/gpu/drm/drm_connector.c        | 79
>++++++++++++++++++++++++++++++++++
>>  drivers/gpu/drm/i915/intel_atomic.c    |  1 +
>>  drivers/gpu/drm/i915/intel_connector.c | 63 +++++++++++++++++++++++++++
>>  drivers/gpu/drm/i915/intel_drv.h       |  1 +
>>  drivers/gpu/drm/i915/intel_hdmi.c      | 19 ++++++++
>>  include/drm/drm_connector.h            | 17 ++++++++
>>  include/uapi/drm/drm_mode.h            | 33 ++++++++++++++
>>  8 files changed, 217 insertions(+)
>>
>> --
>> 1.9.1
>>