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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9E2D6C001DB for ; Thu, 3 Aug 2023 18:10:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230018AbjHCSKa (ORCPT ); Thu, 3 Aug 2023 14:10:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36934 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229815AbjHCSKP (ORCPT ); Thu, 3 Aug 2023 14:10:15 -0400 Received: from phobos.denx.de (phobos.denx.de [IPv6:2a01:238:438b:c500:173d:9f52:ddab:ee01]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8F0123C20 for ; Thu, 3 Aug 2023 11:10:13 -0700 (PDT) Received: from [127.0.0.1] (p578adb1c.dip0.t-ipconnect.de [87.138.219.28]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: marex@denx.de) by phobos.denx.de (Postfix) with ESMTPSA id C4A3E86839; Thu, 3 Aug 2023 20:10:10 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=denx.de; s=phobos-20191101; t=1691086211; bh=fpuHp8OO6h5mevOgIeHsP5FLeL9qrPSYZmeq+L8xvLk=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=EF1Sp2Z46iR/82qNBP9O0RKnEctp3wFsIYKTiMoZeGS7DoLm8WQRqjiYL3YnnZ7t5 pI9yEQap9hzBdXcoM3IQXyJhuEt9F9l9Y/6mzmmI1FQG9OdHE0YBGUJbDLoYfKbuJ3 d9g24kE5vjJSRvN/hNBY9mpRmM3oX7cn/5rvNT3TvN5raEgyA63GoDJtpwjNVc2wYJ dvW3IxwagPu0NZ1F1WXc/n66UM7N6oP/1P6v1k0dg7AggfPcRekwXr2O+BbiRNQdWV 80TLtTw0fpBuijkV1cx+O60LKIO5QPA5oCHH9z/3+xv6T5jw2p6G7zsmRmOqX8p6sB H/CihvJUVzR5w== Message-ID: <25f3026f-3d97-a5ac-862a-da6dc5f8d830@denx.de> Date: Thu, 3 Aug 2023 20:10:10 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.1 Subject: Re: [PATCH] Revert "drm/bridge: lt9611: Do not generate HFP/HBP/HSA and EOT packet" Content-Language: en-US To: Rob Clark , Dmitry Baryshkov Cc: Amit Pundir , Neil Armstrong , Robert Foss , Jonas Karlman , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Jernej Skrabec , Abhinav Kumar , Laurent Pinchart , Andrzej Hajda , Jagan Teki References: <20230802-revert-do-not-generate-hfp-hbp-hsa-eot-packet-v1-1-f8a20084e15a@linaro.org> <5cf0e3fa-f66d-06c4-cfda-c48efd8c6508@linaro.org> From: Marek Vasut In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Virus-Scanned: clamav-milter 0.103.8 at phobos.denx.de X-Virus-Status: Clean Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/2/23 20:49, Rob Clark wrote: > On Wed, Aug 2, 2023 at 11:16 AM Dmitry Baryshkov > wrote: >> >> On Wed, 2 Aug 2023 at 20:34, Marek Vasut wrote: >>> >>> On 8/2/23 15:38, Dmitry Baryshkov wrote: >>>> On 02/08/2023 11:52, Neil Armstrong wrote: >>>>> This reverts commit [1] to fix display regression on the Dragonboard 845c >>>>> (SDM845) devboard. >>>>> >>>>> There's a mismatch on the real action of the following flags: >>>>> - MIPI_DSI_MODE_VIDEO_NO_HSA >>>>> - MIPI_DSI_MODE_VIDEO_NO_HFP >>>>> - MIPI_DSI_MODE_VIDEO_NO_HBP >>>>> which leads to a non-working display on qcom platforms. >>>>> >>>>> [1] 8ddce13ae696 ("drm/bridge: lt9611: Do not generate HFP/HBP/HSA and >>>>> EOT packet") >>>>> >>>>> Cc: Marek Vasut >>>>> Cc: Robert Foss >>>>> Cc: Jagan Teki >>>>> Cc: Dmitry Baryshkov >>>>> Cc: Abhinav Kumar >>>>> Fixes: 8ddce13ae69 ("drm/bridge: lt9611: Do not generate HFP/HBP/HSA >>>>> and EOT packet") >>>>> Reported-by: Amit Pundir >>>>> Link: >>>>> https://lore.kernel.org/r/CAMi1Hd0TD=2z_=bcDrht3H_wiLvAFcv8Z-U_r_KUOoeMc6UMjw@mail.gmail.com/ >>>>> Signed-off-by: Neil Armstrong >>>>> --- >>>>> drivers/gpu/drm/bridge/lontium-lt9611.c | 4 +--- >>>>> 1 file changed, 1 insertion(+), 3 deletions(-) >>>>> >>>> Acked-by: Dmitry Baryshkov #fix db845c >>>> >>>> The boards broken by [1] are used in production by different parties >>>> since 5.10, breaking them doesn't seem more acceptable than breaking the >>>> new out-of-tree iMX8m hardware. >>> >>> The MX8M is also in-tree, so this does not apply. >> >> v6.5-rc4: >> >> $ git grep lontium,lt9611 | grep -v 9611uxc >> Documentation/devicetree/bindings/display/bridge/lontium,lt9611.yaml:$id: >> http://devicetree.org/schemas/display/bridge/lontium,lt9611.yaml# >> Documentation/devicetree/bindings/display/bridge/lontium,lt9611.yaml: >> - lontium,lt9611 >> Documentation/devicetree/bindings/display/bridge/lontium,lt9611.yaml: >> compatible = "lontium,lt9611"; >> arch/arm64/boot/dts/qcom/sdm845-db845c.dts: compatible = "lontium,lt9611"; >> drivers/gpu/drm/bridge/lontium-lt9611.c: { "lontium,lt9611", 0 }, >> drivers/gpu/drm/bridge/lontium-lt9611.c: { .compatible = "lontium,lt9611" }, >> >> next-20230802: >> >> $ git grep lontium,lt9611 | grep -v 9611uxc >> Documentation/devicetree/bindings/display/bridge/lontium,lt9611.yaml:$id: >> http://devicetree.org/schemas/display/bridge/lontium,lt9611.yaml# >> Documentation/devicetree/bindings/display/bridge/lontium,lt9611.yaml: >> - lontium,lt9611 >> Documentation/devicetree/bindings/display/bridge/lontium,lt9611.yaml: >> compatible = "lontium,lt9611"; >> arch/arm64/boot/dts/qcom/sdm845-db845c.dts: compatible = "lontium,lt9611"; >> drivers/gpu/drm/bridge/lontium-lt9611.c: { "lontium,lt9611", 0 }, >> drivers/gpu/drm/bridge/lontium-lt9611.c: { .compatible = "lontium,lt9611" }, >> >> Your device is not in the tree. Your commit broke existing users. >> >> Can we please end the argument, land the fix (this revert) for 6.5 and >> work on the solution for 6.6 or 6.7? >> > > Even if they were in-tree, breaking existing hw means revert and > try-again. Especially as we get into later -rc's Then just apply the revert, I don't have time to debug this right this moment, and it is anyway meaningless until I can look at the bus with DSI bus analyzer.