linux-kernel - Re: [PATCH 06/26] drm/bridge: add devm_drm_of_find

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <DEZSCVYVCZ71.1BRL4LGVYAZAX@bootlin.com>
Date: Tue, 16 Dec 2025 17:36:07 +0100
From: "Luca Ceresoli" <luca.ceresoli@...tlin.com>
To: "Maxime Ripard" <mripard@...nel.org>
Cc: "Andrzej Hajda" <andrzej.hajda@...el.com>, "Neil Armstrong"
 <neil.armstrong@...aro.org>, "Robert Foss" <rfoss@...nel.org>, "Laurent
 Pinchart" <Laurent.pinchart@...asonboard.com>, "Jonas Karlman"
 <jonas@...boo.se>, "Jernej Skrabec" <jernej.skrabec@...il.com>, "Maarten
 Lankhorst" <maarten.lankhorst@...ux.intel.com>, "Thomas Zimmermann"
 <tzimmermann@...e.de>, "David Airlie" <airlied@...il.com>, "Simona Vetter"
 <simona@...ll.ch>, "Jonathan Corbet" <corbet@....net>, "Alexey Brodkin"
 <abrodkin@...opsys.com>, "Phong LE" <ple@...libre.com>, "Liu Ying"
 <victor.liu@....com>, "Shawn Guo" <shawnguo@...nel.org>, "Sascha Hauer"
 <s.hauer@...gutronix.de>, "Pengutronix Kernel Team"
 <kernel@...gutronix.de>, "Fabio Estevam" <festevam@...il.com>, "Adrien
 Grassein" <adrien.grassein@...il.com>, "Laurent Pinchart"
 <laurent.pinchart+renesas@...asonboard.com>, "Tomi Valkeinen"
 <tomi.valkeinen+renesas@...asonboard.com>, "Kieran Bingham"
 <kieran.bingham+renesas@...asonboard.com>, "Geert Uytterhoeven"
 <geert+renesas@...der.be>, "Magnus Damm" <magnus.damm@...il.com>, "Kevin
 Hilman" <khilman@...libre.com>, "Jerome Brunet" <jbrunet@...libre.com>,
 "Martin Blumenstingl" <martin.blumenstingl@...glemail.com>, "Chun-Kuang Hu"
 <chunkuang.hu@...nel.org>, "Philipp Zabel" <p.zabel@...gutronix.de>,
 "Matthias Brugger" <matthias.bgg@...il.com>, "AngeloGioacchino Del Regno"
 <angelogioacchino.delregno@...labora.com>, "Anitha Chrisanthus"
 <anitha.chrisanthus@...el.com>, "Edmund Dea" <edmund.j.dea@...el.com>,
 "Inki Dae" <inki.dae@...sung.com>, "Seung-Woo Kim"
 <sw0312.kim@...sung.com>, "Kyungmin Park" <kyungmin.park@...sung.com>,
 "Krzysztof Kozlowski" <krzk@...nel.org>, "Alim Akhtar"
 <alim.akhtar@...sung.com>, "Hui Pu" <Hui.Pu@...ealthcare.com>, "Thomas
 Petazzoni" <thomas.petazzoni@...tlin.com>,
 <dri-devel@...ts.freedesktop.org>, <linux-kernel@...r.kernel.org>,
 <linux-doc@...r.kernel.org>, <imx@...ts.linux.dev>,
 <linux-arm-kernel@...ts.infradead.org>,
 <linux-renesas-soc@...r.kernel.org>, <linux-amlogic@...ts.infradead.org>,
 <linux-mediatek@...ts.infradead.org>, <linux-samsung-soc@...r.kernel.org>
Subject: Re: [PATCH 06/26] drm/bridge: add devm_drm_of_find_bridge

Hi Maxime,

On Tue Dec 16, 2025 at 2:49 PM CET, Maxime Ripard wrote:
[...]
>> Not sure why, but it's taking a while before I grasp your ideas about this
>> series and meld them with mine. I hopefully got a clear POV now, so based
>> on it my plan is to rework this series to:
>>
>>  * keep drm_of_find_bridge() but renamed to of_drm_get_bridge(), and keep
>>    patches 1-5 (with the changes suggested by you and Louis, nothing big
>>    and all already sent in v2)
>
> I don't think we should use that name, but on principle, yes.

OK about the rename. I just had sent this email before you requested the
rename. v3 is in the works with the of_drm_find_and_get_bridge() name.

>>  * not add devm_drm_of_find_bridge()
>
> Yep.
>
>>  * add next_bridge pointer to struct drm_bridge and call
>>    drm_bridge_put(bridge->next_bridge) in __drm_bridge_free, document it
>
> We don't have to at this point, you can add next_bridge to the
> drm_bridge pointer if you want, but I don't consider it a prerequisite.
> If we don't we would have to create drm_bridge_funcs->destroy
> implemnentations to give up the driver pointer reference though. Your
> call.

There's a destroy finc already, so I'm adding the next_bridge pointer in v3
along with some driver conversions, including one where the destroy hook is
needed.

>>  * convert patches 7-26 to use bridge->next_bridge where applicable,
>>    or to do something different when needed
>
> Depending on your decision above, we'd need to either convert them to
> use drm_bridge->next_bridge or create a destroy hook for them. Either
> way is fine for me.
>
>>  * maybe remove part of patches 7-26 just to reduce spam and rework effort
>>    in case of further iterations, to send them separately once the approach
>>    is accepted
>>
>> Does it look OK?

Cool, thanks for acking. v3 is just a testing round away from being sent.

Luca

--
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com