[PATCH] drm/mediatek: Add MT8188 Overlay Driver Data

[AngeloGioacchino Del Regno]

Il 26/02/24 09:21, Fei Shao ha scritto:
> On Thu, Feb 22, 2024 at 4:43 PM AngeloGioacchino Del Regno
> <angelogioacchino.delregno at collabora.com> wrote:
>>
>> Il 21/02/24 17:56, Justin Green ha scritto:
>>> Add MT8188 overlay driver configuration data. This change consequently
>>> enables 10-bit overlay support on MT8188 devices.
>>>
>>> Tested by running ChromeOS UI on MT8188 and using modetest -P. AR30 and
>>> BA30 overlays are confirmed to work from modetest.
>>>
>>> Signed-off-by: Justin Green <greenjustin at chromium.org>
>>> Tested-by: Justin Green <greenjustin at chromium.org>
>>
>> Hello Justin,
>>
>> I'm 99.9% sure that you don't need this, you can just use compatibles
>>
>> compatible = "mediatek,mt8188-disp-ovl", "mediatek,mt8195-disp-ovl";
>>
>> as they *are* indeed compatible, and MT8188 does support AFBC as well.
> 
> Hi,
> 
> I confirmed that I can lit up the MT8188 display with that plus a
> follow-up patch [1].
> Otherwise a compatible sequence of mt8188, mt8195 and mt8192 would be
> needed, but that would be somewhat redundant.
> 

Actually, that wouldn't be MT8192, but MT8183 - following MT8195's devicetree,

so it would be

compatible = "mediatek,mt8188-disp-ovl", "mediatek,mt8195-disp-ovl",
              "mediatek,mt8183-disp-ovl";

And yes that could be redundant, but I'm not sure that adding a compatible
string to the mtk_drm_drv matches is a good idea.

I'd be more for using the triple compatible strings in there instead, as it'd
be like that for only *one* node and not more than that - IMO, that is totally
acceptable and it's also the best (and lightest) solution.

Cheers,
Angelo

> [1]: https://lore.kernel.org/all/20240226080721.3331649-1-fshao@chromium.org/
> 
> Regards,
> Fei
>