Re: [PATCH v2 0/5] 180 degrees rotation support for NVIDIA Tegra DRM

From: Dmitry Osipenko
Date: Wed Jun 17 2020 - 12:27:27 EST


17.06.2020 12:34, Daniel Stone ÐÐÑÐÑ:
> Hi,
>
> On Tue, 16 Jun 2020 at 22:16, Dmitry Osipenko <digetx@xxxxxxxxx> wrote:
>> The panel's orientation could be parsed by any panel driver and then
>> assigned as the connector's property in order to allow userspace/FB-core
>> to decide what to do with the rotated display. Apparently upstream
>> kernel supports only that one Samsung device which has display panel
>> mounted upside-down and it already uses the custom DT properties for
>> achieving the 180 rotation. So I don't quite see any panel drivers that
>> instantly could benefit from using the rotation property. Perhaps I can
>> add the orientation support to the panel-simple driver, but will it be
>> useful to anyone?
>
> Yes, exposing it to userspace is helpful, since Weston at least will
> parse the property and then apply the correct transform:
> https://gitlab.freedesktop.org/wayland/weston/-/merge_requests/315

Hello Daniel,

Thank you very much for the pointer! I missed that Weston now uses the
panel's orientation. I gave a quick test to the recent Weston and indeed
it applies the transform in accordance to the connector's orientation
property.