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Date:   Fri, 18 Mar 2022 17:10:09 +0100
From:   Paul Kocialkowski <paul.kocialkowski@bootlin.com>
To:     Jagan Teki <jagan@amarulasolutions.com>
Cc:     dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>,
        Linus Walleij <linus.walleij@linaro.org>
Subject: Re: [PATCH] drm: of: Properly try all possible cases for
 bridge/panel detection
Message-ID: <YjSu4QSocJkvI1QQ@aptenodytes>
References: <20220309143200.111292-1-paul.kocialkowski@bootlin.com>
 <CAMty3ZAZKHTqfR=ecRgpzJtVefhFFrSpcEqueSQ6K-=Q75XU4w@mail.gmail.com>
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Hi Jagan,

On Fri 18 Mar 22, 21:35, Jagan Teki wrote:
> Hi Paul,
>=20
> On Wed, Mar 9, 2022 at 8:02 PM Paul Kocialkowski
> <paul.kocialkowski@bootlin.com> wrote:
> >
> > While bridge/panel detection was initially relying on the usual
> > port/ports-based of graph detection, it was recently changed to
> > perform the lookup on any child node that is not port/ports
> > instead when such a node is available, with no fallback on the
> > usual way.
> >
> > This results in breaking detection when a child node is present
> > but does not contain any panel or bridge node, even when the
> > usual port/ports-based of graph is there.
>=20
> Can you add that pipeline example on the commit message, it gives more
> information on specific use cases why the existing code breaks.

Ah I just sent v2 before reading your message.

Well I think the description says it all: the problem shows as soon as ther=
e's
a child node to the node passed to drm_of_find_panel_or_bridge and it's rea=
lly
independent from the of graph setup in the end.

I think Maxime put some examples on the original thread (v4 of your patch).

Paul

--=20
Paul Kocialkowski, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com

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