Re: [PATCH v13 05/10] drm/bridge: anx7625: Check for Type-C during panel registration

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" <rfoss@kernel.org>,
	"Laurent Pinchart" <Laurent.pinchart@ideasonboard.com>,
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	"Daniel Vetter" <daniel@ffwll.ch>,
	"Rob Herring" <robh+dt@kernel.org>,
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	"Heikki Krogerus" <heikki.krogerus@linux.intel.com>,
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	"Rafael J . Wysocki" <rafael@kernel.org>,
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	<angelogioacchino.delregno@collabora.com>,
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	devicetree@vger.kernel.org, "Allen Chen" <allen.chen@ite.com.tw>,
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	"Thomas Zimmermann" <tzimmermann@suse.de>,
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	linux-acpi@vger.kernel.org,
	"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
Subject: Re: [PATCH v13 05/10] drm/bridge: anx7625: Check for Type-C during panel registration
Date: Mon, 6 Mar 2023 13:51:44 +0200	[thread overview]
Message-ID: <ZAXT0JFjERb8Q36f@smile.fi.intel.com> (raw)
In-Reply-To: <20230303143350.815623-6-treapking@chromium.org>

On Fri, Mar 03, 2023 at 10:33:45PM +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.

...

> +	port_node = of_graph_get_port_by_id(np, 1);
> +	count = typec_mode_switch_node_count(&port_node->fwnode);

Do you need to drop reference count here?
(I don't know myself, so, please check this)

If no, patch LGTM.

> +	if (count)
> +		return 0;

-- 
With Best Regards,
Andy Shevchenko