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Message-ID: <4211eac2-5310-e343-2d3a-ccea908e9262@intel.com>
Date:   Wed, 22 Mar 2023 15:42:12 +0100
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Subject: Re: [PATCH v2] drm/bridge: lt8912b: return EPROBE_DEFER if bridge is
 not found
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To:     Francesco Dolcini <francesco@dolcini.it>,
        Adrien Grassein <adrien.grassein@gmail.com>,
        Neil Armstrong <neil.armstrong@linaro.org>,
        Robert Foss <rfoss@kernel.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>,
        dri-devel@lists.freedesktop.org
Cc:     Matheus Castello <matheus.castello@toradex.com>,
        linux-kernel@vger.kernel.org, stable@vger.kernel.org,
        Francesco Dolcini <francesco.dolcini@toradex.com>
References: <20230322143821.109744-1-francesco@dolcini.it>
From:   Andrzej Hajda <andrzej.hajda@intel.com>
Organization: Intel Technology Poland sp. z o.o. - ul. Slowackiego 173, 80-298
 Gdansk - KRS 101882 - NIP 957-07-52-316
In-Reply-To: <20230322143821.109744-1-francesco@dolcini.it>
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On 22.03.2023 15:38, Francesco Dolcini wrote:
> From: Matheus Castello <matheus.castello@toradex.com>
>
> Returns EPROBE_DEFER when of_drm_find_bridge() fails, this is consistent
> with what all the other DRM bridge drivers are doing and this is
> required since the bridge might not be there when the driver is probed
> and this should not be a fatal failure.
>
> Cc: <stable@vger.kernel.org>
> Fixes: 30e2ae943c26 ("drm/bridge: Introduce LT8912B DSI to HDMI bridge")
> Signed-off-by: Matheus Castello <matheus.castello@toradex.com>
> Signed-off-by: Francesco Dolcini <francesco.dolcini@toradex.com>

Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>

Regards
Andrzej

> ---
> v2: use dev_err_probe() instead of dev_dbg() (Laurent)
> ---
>   drivers/gpu/drm/bridge/lontium-lt8912b.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/lontium-lt8912b.c b/drivers/gpu/drm/bridge/lontium-lt8912b.c
> index 2019a8167d69..b40baced1331 100644
> --- a/drivers/gpu/drm/bridge/lontium-lt8912b.c
> +++ b/drivers/gpu/drm/bridge/lontium-lt8912b.c
> @@ -676,8 +676,8 @@ static int lt8912_parse_dt(struct lt8912 *lt)
>   
>   	lt->hdmi_port = of_drm_find_bridge(port_node);
>   	if (!lt->hdmi_port) {
> -		dev_err(lt->dev, "%s: Failed to get hdmi port\n", __func__);
> -		ret = -ENODEV;
> +		ret = -EPROBE_DEFER;
> +		dev_err_probe(lt->dev, ret, "%s: Failed to get hdmi port\n", __func__);
>   		goto err_free_host_node;
>   	}
>