Re: [PATCH v3 08/14] drm/mediatek: Add DRM_MODE_ROTATE_0 to rotation property

["Shawn Sung (宋孝謙)" <Shawn.Sung@mediatek.com>]

Hi Doug,

On Thu, 2024-10-24 at 13:47 -0700, Doug Anderson wrote:
>  	 
> External email : Please do not click links or open attachments until
> you have verified the sender or the content.
>  Hi,
> 
> On Wed, Jun 19, 2024 at 9:39 AM Hsiao Chien Sung via B4 Relay
> <devnull+shawn.sung.mediatek.com@kernel.org> wrote:
> >
> > From: Hsiao Chien Sung <shawn.sung@mediatek.com>
> >
> > Always add DRM_MODE_ROTATE_0 to rotation property to meet
> > IGT's (Intel GPU Tools) requirement.
> >
> > Reviewed-by: CK Hu <ck.hu@mediatek.com>
> > Reviewed-by: AngeloGioacchino Del Regno <
> angelogioacchino.delregno@collabora.com>
> > Fixes: 119f5173628a ("drm/mediatek: Add DRM Driver for Mediatek SoC
> MT8173.")
> > Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
> > ---
> >  drivers/gpu/drm/mediatek/mtk_ddp_comp.h |  6 +++++-
> >  drivers/gpu/drm/mediatek/mtk_disp_ovl.c | 17 +++++------------
> >  drivers/gpu/drm/mediatek/mtk_plane.c    |  2 +-
> >  3 files changed, 11 insertions(+), 14 deletions(-)
> 
> FWIW, this patch got into ChromeOS's 5.15 branch via stable merge and
> apparently broke things. As a short term fix we've reverted it there:
> 
> https://crrev.com/c/5960799
 
Thank you for reporting this issue. We are currently investigating the
bug.

Since I am unable to access the Google issue tracker [1], could you
please provide more details about this bug? The message in the revert
commit mentions "hana/sycamore360" (MT8173) and it appears that there
is a rotation issue in tablet mode.

> 
> ...apparently the patch is fine on newer kernels so maybe there is a
> missing dependency? Hopefully someone on this list can dig into this
> and either post the revert to stable 5.15 kernels or suggest
> additional backports.
> 

There are known issues [2] regarding forward compatibility. Could you
confirm whether this patch is unable to resolve the mentioned problem?
Thanks.

[1] https://issuetracker.google.com/issues/369688659
[2] 
https://patchwork.kernel.org/project/linux-mediatek/list/?series=896964

> 
> -Doug

Best regards,
Shawn