Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Message-ID: <b308b17c-37fa-220d-d76b-9274054597e7@samsung.com>
Date:   Wed, 31 Mar 2021 11:05:59 +0200
MIME-Version: 1.0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:88.0)
        Gecko/20100101 Thunderbird/88.0
Subject: Re: [PATCH v2 01/14] drm/bridge: Fix the stop condition of
 drm_bridge_chain_pre_enable()
Content-Language: en-GB
To:     Douglas Anderson <dianders@chromium.org>,
        Neil Armstrong <narmstrong@baylibre.com>,
        Laurent Pinchart <Laurent.pinchart@ideasonboard.com>,
        Jonas Karlman <jonas@kwiboo.se>,
        Jernej Skrabec <jernej.skrabec@siol.net>,
        Sam Ravnborg <sam@ravnborg.org>
Cc:     robdclark@chromium.org, dri-devel@lists.freedesktop.org,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@linux.ie>, linux-arm-msm@vger.kernel.org,
        Steev Klimaszewski <steev@kali.org>,
        Stephen Boyd <swboyd@chromium.org>,
        Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>,
        Boris Brezillon <boris.brezillon@collabora.com>,
        Bjorn Andersson <bjorn.andersson@linaro.org>,
        linux-kernel@vger.kernel.org
From:   Andrzej Hajda <a.hajda@samsung.com>
In-Reply-To: <20210329195255.v2.1.If62a003f76a2bc4ccc6c53565becc05d2aad4430@changeid>
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="utf-8"
CMS-TYPE: 201P
References: <20210330025345.3980086-1-dianders@chromium.org>
        <CGME20210330025413eucas1p1613dea9b53bcb06d93eb210c6dfd1254@eucas1p1.samsung.com>
        <20210329195255.v2.1.If62a003f76a2bc4ccc6c53565becc05d2aad4430@changeid>
Precedence: bulk

Hi Douglas,

W dniu 30.03.2021 o 04:53, Douglas Anderson pisze:
> The drm_bridge_chain_pre_enable() is not the proper opposite of
> drm_bridge_chain_post_disable(). It continues along the chain to
> _before_ the starting bridge. Let's fix that.
>
> Fixes: 05193dc38197 ("drm/bridge: Make the bridge chain a double-linked list")
> Signed-off-by: Douglas Anderson <dianders@chromium.org>
> ---
>
> (no changes since v1)
>
>   drivers/gpu/drm/drm_bridge.c | 3 +++
>   1 file changed, 3 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
> index 64f0effb52ac..044acd07c153 100644
> --- a/drivers/gpu/drm/drm_bridge.c
> +++ b/drivers/gpu/drm/drm_bridge.c
> @@ -522,6 +522,9 @@ void drm_bridge_chain_pre_enable(struct drm_bridge *bridge)
>   	list_for_each_entry_reverse(iter, &encoder->bridge_chain, chain_node) {
>   		if (iter->funcs->pre_enable)
>   			iter->funcs->pre_enable(iter);
> +
> +		if (iter == bridge)
> +			break;


Looking at the bridge chaining code always makes me sick :) but beside 
this the change looks correct, and follows 
drm_atomic_bridge_chain_pre_enable.

Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>

Regards
Andrzej

>   	}
>   }
>   EXPORT_SYMBOL(drm_bridge_chain_pre_enable);