linux-kernel - Re: [PATCH 3/4] drm/uapi: document the USB subconnector type

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

Date:   Fri, 18 Aug 2023 06:24:32 +0000
From:   Simon Ser <contact@...rsion.fr>
To:     Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
Cc:     Laurent Pinchart <laurent.pinchart@...asonboard.com>,
        dri-devel@...ts.freedesktop.org, amd-gfx@...ts.freedesktop.org,
        Andrzej Hajda <andrzej.hajda@...el.com>,
        Janne Grunau <j@...nau.net>, Robert Foss <rfoss@...nel.org>,
        Rodrigo Siqueira <Rodrigo.Siqueira@....com>,
        Jernej Skrabec <jernej.skrabec@...il.com>,
        Andy Gross <agross@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        Jonas Karlman <jonas@...boo.se>, Leo Li <sunpeng.li@....com>,
        intel-gfx@...ts.freedesktop.org,
        Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>,
        Maxime Ripard <mripard@...nel.org>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        Neil Armstrong <neil.armstrong@...aro.org>,
        Bjorn Andersson <andersson@...nel.org>,
        "Pan, Xinhui" <Xinhui.Pan@....com>, linux-kernel@...r.kernel.org,
        Konrad Dybcio <konrad.dybcio@...aro.org>,
        Alex Deucher <alexander.deucher@....com>,
        Christian König <christian.koenig@....com>
Subject: Re: [PATCH 3/4] drm/uapi: document the USB subconnector type

On Thursday, August 17th, 2023 at 21:33, Dmitry Baryshkov <dmitry.baryshkov@...aro.org> wrote:

> We have been looking for a way to document that the corresponding DP
> port is represented by the USB connector on the device.
> 
> Consequently, I believe the best way to document it, would be to use
> DisplayPort / USB, when there is no dongle connected, switching to
> DisplayPort / HDMI, DisplayPort / VGA, DisplayPort / DisplayPort, etc.
> when the actual dongle / display is connected and then switching back to
> the DisplayPort / USB when it gets disconnected.
> 
> If this sounds good to all parties, I'll post v2, adding this
> explanation to the cover letter.

But how can user-space discover that the port is USB-C when it's
connected? That information is lost at this point.

(In addition, this clashes with the existing semantics of the
subconnector prop as discussed before: USB-C is not sub-, it's super-.)