From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9C1EEE8B386 for ; Wed, 4 Feb 2026 01:10:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:References:Cc:To:Subject:From:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ro6VqhMxsjofyYNi+p5gticfSsMMFPfjQqGDTGdq+b8=; b=m5Jm3oziOMNDEbkcNW3mFu6Rhq BX7VkSh1N0b54tnJe5/zwedeHzijRxz9IiqkOdRufgZC1R+R+wJGEI1ifMN3oQOcwUIOlyPZE9UKS cz/L69igaZhmN5rRoC1fl9IetWaZ4OGRRM3bC1wJu1OQu1Mi7X+C5u2xbNXPVcO7kWcsxL4oIexPb 5KLM5/HYnxS718SIFANpQd8VPdO8DG1OUT0Dkz+dC9jAjlE8zdnZhdA8ZyBHQhRbEqO6P8/17r8V8 GK5d1knEXKDIcYkhfZztax55cYadwUESCI76qsvM1Yz3qZdmmNpp6WZEkTllddZnERE8v1NcNgY7Y q03oB3EQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vnRPW-00000007fTw-1o76; Wed, 04 Feb 2026 01:10:26 +0000 Received: from mail-m81126.xmail.ntesmail.com ([156.224.81.126]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vnRPR-00000007fTR-2yY0; Wed, 04 Feb 2026 01:10:24 +0000 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 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; X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260203_171022_352935_89D9D7E0 X-CRM114-Status: GOOD ( 21.59 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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