From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-m32105.qiye.163.com (mail-m32105.qiye.163.com [220.197.32.105]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B67DD350D4D; Wed, 4 Feb 2026 04:39:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.32.105 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770180026; cv=none; b=l2qTTL2Dc/EdtEFwY+GwKwmC8NiOBXQF8Pv+1sQcaD6MCP4m7eWzoIys9otW5pi+IKuY8qP9u6beE9ynEwm4Sox6aNUW7jVlD/Pmh+nqy/jP0ypqA3/moQAvCbiR49RP3DvTnom7zmet7O3vqpGXH8bhyENI+X5qXMQ//81XQ28= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770180026; c=relaxed/simple; bh=N07gY89EuSEYf36dEC4Rpxftlpaz3On9AMbxSIwK9gY=; h=Message-ID:Date:MIME-Version:From:Subject:To:Cc:References: In-Reply-To:Content-Type; b=p82x64kpJPwCZNUytXbyLhTm5GVlKQNQb1BVI3ihRkMaXSRHkKbgd+TUu5UNOFzKnViigz6RrmMIWjVrj1xGUFH3ZJbsveDNiKtAfHuVniVULPs47LXhXqBLvD0eAHj+bmkGBw46x/9B9zauKpH1csk+FMtJYQlh0yDFT99gvXg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com; spf=pass smtp.mailfrom=rock-chips.com; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b=PdtvcqXr; arc=none smtp.client-ip=220.197.32.105 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b="PdtvcqXr" Received: from [172.16.12.43] (unknown [58.22.7.114]) by smtp.qiye.163.com (Hmail) with ESMTP id 330509a94; Wed, 4 Feb 2026 09:10:05 +0800 (GMT+08:00) Message-ID: <8c305f74-7fa7-4798-b1b3-e96544d962a1@rock-chips.com> Date: Wed, 4 Feb 2026 09:09:07 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Damon Ding Subject: Re: [PATCH v8 05/18] drm/bridge: Move legacy bridge driver out of imx directory for multi-platform use To: Luca Ceresoli , andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, dmitry.baryshkov@oss.qualcomm.com Cc: Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, inki.dae@samsung.com, sw0312.kim@samsung.com, kyungmin.park@samsung.com, krzk@kernel.org, alim.akhtar@samsung.com, jingoohan1@gmail.com, p.zabel@pengutronix.de, hjc@rock-chips.com, heiko@sntech.de, andy.yan@rock-chips.com, dianders@chromium.org, m.szyprowski@samsung.com, jani.nikula@intel.com, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-rockchip@lists.infradead.org References: <20251217093321.3108939-1-damon.ding@rock-chips.com> <20251217093321.3108939-6-damon.ding@rock-chips.com> <7256ecf9-b10b-428c-a1a6-e35e80a686ed@rock-chips.com> <9e1da672-a52d-4ec3-a20a-fe6f8ca15496@rock-chips.com> Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-HM-Tid: 0a9c26330b5c03a3kunme492eb66731d02 X-HM-MType: 1 X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFDSUNOT01LS0k3V1ktWUFJV1kPCRoVCBIfWUFZGU1KQlYdTB0aGRgfSRlIHU1WFRQJFh oXVRMBExYaEhckFA4PWVdZGBILWUFZTkNVSUlVTFVKSk9ZV1kWGg8SFR0UWUFZT0tIVUpLSEpKQk 1VSktLVUpCWQY+ DKIM-Signature: a=rsa-sha256; b=PdtvcqXrIboBxzk6mrQxMh8OFknDSWkG8VsQx3P2oelUvZoMue4STcE+QfhITy/PiSZqtgQYee4sBfRWs14gKK0t47AQ3BXE7Nr3wCtaOHKY9WaYy5G//B0ZE4uGhgQl/TKkSj0hcrsxCsAcdXg1gNWy7TRdCUVD4w3MwfbcuEU=; c=relaxed/relaxed; s=default; d=rock-chips.com; v=1; bh=ro6VqhMxsjofyYNi+p5gticfSsMMFPfjQqGDTGdq+b8=; h=date:mime-version:subject:message-id:from; Hi Luca, On 2/3/2026 6:11 PM, Luca Ceresoli wrote: > Hello Damon, > > On Tue Feb 3, 2026 at 2:31 AM CET, Damon Ding wrote: >> Hi, >> >> On 2/2/2026 10:54 AM, Damon Ding wrote: >>> Hi Luca, >>> >>> On 1/31/2026 8:33 PM, Luca Ceresoli wrote: >>>> Hello Damon, Dmitry, >>>> >>>> On Wed Dec 17, 2025 at 10:33 AM CET, Damon Ding wrote: >>>>> As suggested by Dmitry, the DRM legacy bridge driver can be pulled >>>>> out of imx/ subdir for multi-platform use. The driver is also renamed >>>>> to make it more generic and suitable for platforms other than i.MX. >>>>> >>>>> Signed-off-by: Damon Ding >>>>> Suggested-by: Dmitry Baryshkov >>>>> Tested-by: Marek Szyprowski >>>>> >>>>> --- >>>>> >>>>> Changes in v7: >>>>> - Rename legacy-bridge to of-display-mode-bridge. >>>>> - Remove unnecessary API drm_bridge_is_legacy(). >>>> >>>> ... >>>> >>>>> --- a/drivers/gpu/drm/bridge/Kconfig >>>>> +++ b/drivers/gpu/drm/bridge/Kconfig >>>>> @@ -244,6 +244,16 @@ config DRM_NXP_PTN3460 >>>>>       help >>>>>         NXP PTN3460 eDP-LVDS bridge chip driver. >>>>> >>>>> +config DRM_OF_DISPLAY_MODE_BRIDGE >>>>> +    tristate >>>>> +    depends on DRM_BRIDGE && OF >>>>> +    help >>>>> +      This is a DRM bridge implementation that uses >>>>> of_get_drm_display_mode >>>>> +      to acquire display mode. >>>>> + >>>>> +      Newer designs should not use this bridge and should use proper >>>>> panel >>>>> +      driver instead. >>>> >>>> "Newer designs should not use this bridge", but in patch 8 you are >>>> introducing a new use ot devm_drm_of_display_mode_bridge(). Shouldn't you >>>> instead "use proper panel driver instead" in patch 8? >>>> >>>> Can you point to the conversation where the converstaion where Dmitry >>>> suggested this change? Maybe it already contains the answer to my >>>> qustion. Also adding a link to that conversation in the commit message >>>> woule be useful. >>>> >>> >>> First of all, thanks for your reviews on this patch series. >>> >>> link: https://lore.kernel.org/all/ >>> xwenycscalzdlpuxytorbiyvej3k7pv3lhxwtadilxq65ipwsv@x5rxm53w5e22/ >>> >>> I think it may be a misleading issue caused by directly copying the >>> previous Kconfig description. Now that the new >>> devm_drm_of_display_mode_bridge() helper has been added, drivers using >>> the panel-bridge framework can rely on it to maintain compatibility with >>> legacy display mode parsing. > > Ah, I think I got the point: the mode description in device tree is legacy, > but the driver itself is not legacy and will be current until we need to > support legacy device tree. Correct? > > If that's correct, this patch looks OK to me with a new Kconfig help text. Right. I want to apply the advanced panel-bridge framework for Exynos DP driver, and this newly added API helps handle the legacy device tree that it supports. The v9 will come soon. > >>> It would be better to update the comment as follows: >>> >>> This is a DRM bridge implementation that uses of_get_drm_display_mode to >>> acquire display mode. >>> >>> It exists for compatibility with legacy display mode parsing, in order >>> to conform to the panel-bridge framework. >>> >> >> Dmitry, what's you take on this? > > Dmitry's opinion would be much more relevant than mine. I don't know much > myself about this driver. > Best regards, Damon