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References: <20230109084101.265664-1-treapking@chromium.org> <20230109084101.265664-6-treapking@chromium.org>
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From:   Chen-Yu Tsai <wenst@chromium.org>
Date:   Mon, 9 Jan 2023 18:11:34 +0800
Message-ID: <CAGXv+5GnLhUfdDzDQ2Y1Hb7gb+rjZzMhLU+38MYR+VHRdUCtkQ@mail.gmail.com>
Subject: Re: [PATCH v9 5/9] drm/bridge: anx7625: Check for Type-C during panel registration
To:     Pin-yen Lin <treapking@chromium.org>
Cc:     Andrzej Hajda <andrzej.hajda@intel.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Robert Foss <robert.foss@linaro.org>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@gmail.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Daniel Scally <djrscally@gmail.com>,
        Heikki Krogerus <heikki.krogerus@linux.intel.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J . Wysocki" <rafael@kernel.org>,
        Prashant Malani <pmalani@chromium.org>,
        Benson Leung <bleung@chromium.org>,
        Guenter Roeck <groeck@chromium.org>,
        Marek Vasut <marex@denx.de>, devicetree@vger.kernel.org,
        =?UTF-8?B?TsOtY29sYXMgRiAuIFIgLiBBIC4gUHJhZG8=?= 
        <nfraprado@collabora.com>, linux-acpi@vger.kernel.org,
        Allen Chen <allen.chen@ite.com.tw>,
        Javier Martinez Canillas <javierm@redhat.com>,
        dri-devel@lists.freedesktop.org,
        Stephen Boyd <swboyd@chromium.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Hsin-Yi Wang <hsinyi@chromium.org>,
        chrome-platform@lists.linux.dev, Xin Ji <xji@analogixsemi.com>,
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        AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>
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On Mon, Jan 9, 2023 at 4:41 PM Pin-yen Lin <treapking@chromium.org> wrote:
>
> The output port endpoints can be connected to USB-C connectors.
> Running drm_of_find_panel_or_bridge() with such endpoints leads to
> a continuous return value of -EPROBE_DEFER, even though there is
> no panel present.
>
> To avoid this, check for the existence of a "mode-switch" property in
> the port endpoint, and skip panel registration completely if so.
>
> Signed-off-by: Pin-yen Lin <treapking@chromium.org>

Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Tested-by: Chen-Yu Tsai <wenst@chromium.org>

on MT8192 based Hayato (ASUS Chromebook Flip CM3200).