2020-04-14 13:42:25

by Simon Ser

[permalink] [raw]
Subject: Re: [PATCH 5/5] drm/i915: Replace "Broadcast RGB" with "RGB quantization range" property

On Monday, April 13, 2020 11:40 PM, Yussuf Khalil <[email protected]> wrote:

> DRM now has a globally available "RGB quantization range" connector
> property. i915's "Broadcast RGB" that fulfils the same purpose is now
> considered deprecated, so drop it in favor of the DRM property.

For a UAPI point-of-view, I'm not sure this is fine. Some user-space
might depend on this property, dropping it would break such user-space.

Can we make this property deprecated but still keep it for backwards
compatibility?


2020-04-15 21:23:08

by Jani Nikula

[permalink] [raw]
Subject: Re: [PATCH 5/5] drm/i915: Replace "Broadcast RGB" with "RGB quantization range" property

On Mon, 13 Apr 2020, Simon Ser <[email protected]> wrote:
> On Monday, April 13, 2020 11:40 PM, Yussuf Khalil <[email protected]> wrote:
>
>> DRM now has a globally available "RGB quantization range" connector
>> property. i915's "Broadcast RGB" that fulfils the same purpose is now
>> considered deprecated, so drop it in favor of the DRM property.
>
> For a UAPI point-of-view, I'm not sure this is fine. Some user-space
> might depend on this property, dropping it would break such user-space.

Agreed.

> Can we make this property deprecated but still keep it for backwards
> compatibility?

Would be nice to make the i915 specific property an "alias" for the new
property, however I'm not sure how you'd make that happen. Otherwise
juggling between the two properties is going to be a nightmare.

BR,
Jani.


--
Jani Nikula, Intel Open Source Graphics Center

2020-04-15 21:24:46

by Jani Nikula

[permalink] [raw]
Subject: Re: [PATCH 5/5] drm/i915: Replace "Broadcast RGB" with "RGB quantization range" property

On Tue, 14 Apr 2020, Jani Nikula <[email protected]> wrote:
> On Mon, 13 Apr 2020, Simon Ser <[email protected]> wrote:
>> On Monday, April 13, 2020 11:40 PM, Yussuf Khalil <[email protected]> wrote:
>>
>>> DRM now has a globally available "RGB quantization range" connector
>>> property. i915's "Broadcast RGB" that fulfils the same purpose is now
>>> considered deprecated, so drop it in favor of the DRM property.
>>
>> For a UAPI point-of-view, I'm not sure this is fine. Some user-space
>> might depend on this property, dropping it would break such user-space.
>
> Agreed.
>
>> Can we make this property deprecated but still keep it for backwards
>> compatibility?
>
> Would be nice to make the i915 specific property an "alias" for the new
> property, however I'm not sure how you'd make that happen. Otherwise
> juggling between the two properties is going to be a nightmare.

Ah, the obvious easy choice is to use the property and enum names
already being used by i915 and gma500, and you have no problem. Perhaps
they're not the names you'd like, but then looking at the total lack of
consistency across property naming makes them fit right in. ;)

BR,
Jani.


--
Jani Nikula, Intel Open Source Graphics Center