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References: <20231102221309.1971910-1-hsinyi@chromium.org> <20231102221309.1971910-5-hsinyi@chromium.org>
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From:   Doug Anderson <dianders@chromium.org>
Date:   Fri, 3 Nov 2023 09:02:55 -0700
Message-ID: <CAD=FV=XEnk1TuWsJB6W5PGisg3_0A3HZMGpxEUrtcDxXK=Z+Eg@mail.gmail.com>
Subject: Re: [PATCH v2 4/4] drm/panel-edp: Choose correct preferred mode
To:     Hsin-Yi Wang <hsinyi@chromium.org>
Cc:     Neil Armstrong <neil.armstrong@linaro.org>,
        Jessica Zhang <quic_jesszhan@quicinc.com>,
        Sam Ravnborg <sam@ravnborg.org>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
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Hi,

On Thu, Nov 2, 2023 at 3:13=E2=80=AFPM Hsin-Yi Wang <hsinyi@chromium.org> w=
rote:
>
> If a non generic edp-panel is under aux-bus, the mode read from edid woul=
d
> still be selected as preferred and results in multiple preferred modes,
> which is ambiguous.
>
> If a hard-coded mode is present, unset the preferred bit of the modes rea=
d
> from edid.
>
> Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
> ---
> v1->v2: split patches from drm_modes.
> ---
>  drivers/gpu/drm/panel/panel-edp.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)

Reviewed-by: Douglas Anderson <dianders@chromium.org>

Do you think this should have a "Fixes?" As per discussion on V1 [1],
this has probably been a bit broken from the beginning, though I guess
it only became a big deal after the AUX bus made it so that the panel
driver commonly had the EDID...

[1] https://lore.kernel.org/r/CAD=3DFV=3DWHzCdiYumsxUm_am+ALqq9SOOrjf=3DJYH=
qJuiKFB+Dnsw@mail.gmail.com