Date:   Mon, 6 Feb 2023 14:11:08 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
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>,
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        Jernej Skrabec <jernej.skrabec@gmail.com>,
        David Airlie <airlied@gmail.com>,
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        Rob Herring <robh+dt@kernel.org>,
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        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>,
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        Lyude Paul <lyude@redhat.com>, linux-acpi@vger.kernel.org,
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        <angelogioacchino.delregno@collabora.com>,
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        =?iso-8859-1?Q?Jos=E9_Exp=F3sito?= <jose.exposito89@gmail.com>
Subject: Re: [PATCH v11 5/9] drm/bridge: anx7625: Check for Type-C during
 panel registration
Message-ID: <Y+DuXKlcAQfErVik@smile.fi.intel.com>
References: <20230204133040.1236799-1-treapking@chromium.org>
 <20230204133040.1236799-6-treapking@chromium.org>
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On Sat, Feb 04, 2023 at 09:30:36PM +0800, Pin-yen Lin 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.

...

> +	/*
> +	 * Don't bother finding a panel if a Type-C `mode-switch` property is
> +	 * present in one of the endpoints.
> +	 */
> +	for_each_endpoint_of_node(np, sw) {
> +		if (of_property_read_bool(sw, "mode-switch")) {

Might be that the same helper can be used here. Dunno if the endpoint traverse
should be used for the other driver as well.

> +			of_node_put(sw);
> +			return 0;
> +		}
> +	}

-- 
With Best Regards,
Andy Shevchenko