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Subject: Re: [PATCH v4 24/24] drm/exynos: dsi: Adjust probe order
To:     Andrzej Hajda <a.hajda@samsung.com>,
        Maxime Ripard <maxime@cerno.tech>,
        Sam Ravnborg <sam@ravnborg.org>,
        Daniel Vetter <daniel.vetter@intel.com>,
        David Airlie <airlied@linux.ie>,
        Jonas Karlman <jonas@kwiboo.se>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Robert Foss <robert.foss@linaro.org>,
        Jernej Skrabec <jernej.skrabec@gmail.com>
Cc:     Sean Paul <sean@poorly.run>, freedreno@lists.freedesktop.org,
        Kyungmin Park <kyungmin.park@samsung.com>,
        linux-kernel@vger.kernel.org,
        Xinliang Liu <xinliang.liu@linaro.org>,
        Seung-Woo Kim <sw0312.kim@samsung.com>,
        Tian Tao <tiantao6@hisilicon.com>,
        Inki Dae <inki.dae@samsung.com>,
        linux-samsung-soc@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        Rob Clark <robdclark@gmail.com>,
        dri-devel@lists.freedesktop.org,
        John Stultz <john.stultz@linaro.org>,
        Chen Feng <puck.chen@hisilicon.com>,
        Xinwei Kong <kong.kongxinwei@hisilicon.com>,
        Joonyoung Shim <jy0922.shim@samsung.com>
From:   Marek Szyprowski <m.szyprowski@samsung.com>
Message-ID: <fc1fbd42-6ed4-9d67-2903-8f9cc2aaad43@samsung.com>
Date:   Fri, 17 Sep 2021 14:35:05 +0200
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References: <20210910101218.1632297-1-maxime@cerno.tech>
        <CGME20210910101445eucas1p172f99ff7fe853052fc457861c3174f9e@eucas1p1.samsung.com>
        <20210910101218.1632297-25-maxime@cerno.tech>
        <29a2111d-024b-4d9e-27ef-e3399509ff32@samsung.com>
Precedence: bulk

Hi,

On 13.09.2021 12:30, Andrzej Hajda wrote:
> W dniu 10.09.2021 o 12:12, Maxime Ripard pisze:
>> Without proper care and an agreement between how DSI hosts and devices
>> drivers register their MIPI-DSI entities and potential components, we can
>> end up in a situation where the drivers can never probe.
>>
>> Most drivers were taking evasive maneuvers to try to workaround this,
>> but not all of them were following the same conventions, resulting in
>> various incompatibilities between DSI hosts and devices.
>>
>> Now that we have a sequence agreed upon and documented, let's convert
>> exynos to it.
>>
>> Signed-off-by: Maxime Ripard <maxime@cerno.tech>
> This patch should be dropped, as it will probably break the driver.
>
> Exynos is already compatible with the pattern
> register-bus-then-get-sink, but it adds/removes panel/bridge
> dynamically, so it creates drm_device without waiting for downstream sink.

Right, this patch breaks Exynos DSI driver operation. Without it, the 
whole series works fine on all Exynos based test boards.

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland