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 4DF5AC53209 for ; Mon, 27 Jul 2026 12:52:57 +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:From:References:Cc:To:Subject: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=PxswdzoAQvQGkPWUS0AeYk7qhI5OcIZi4EoyckriCiQ=; b=RQ/N107zBzUis8dZBc+lLd3/EH vyoSFACULH5326qViAy6l+n08tt/ZnUIY0qD2uId2w+0Khol6XryanEmNx4I56J6V5mfnwWD8slmL Idm9RzY2EbHspNCg1b1oSTDdEVgW0ewtipuo8Ga7A1+h72OEqvwnN1mOQRlvINGLRKoW4HimaWzKf UkKMllSfZ9mrXNHmFFymjAC8jjn6YkyngxGHKlHZozad/Ur6Xy3306pmoEPTlO2hJWOT6jfz7Vhrw Wx8Dv6M3Zw97AEKB2oX8ChRvUDWsPd/NTJXgFH9JM1zNCfkfP36xFdD5ABV7TBy/ahywIjikpfCPq sgVlmRuw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1woKp8-00000002kYZ-2BMR; Mon, 27 Jul 2026 12:52:50 +0000 Received: from mout-p-101.mailbox.org ([80.241.56.151]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1woKp5-00000002kXt-185S; Mon, 27 Jul 2026 12:52:48 +0000 Received: from smtp202.mailbox.org (smtp202.mailbox.org [IPv6:2001:67c:2050:b231:465::202]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-101.mailbox.org (Postfix) with ESMTPS id 4h7z5h4RMrz8tyC; Mon, 27 Jul 2026 14:52:40 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=adamthiede.com; s=MBO0001; t=1785156760; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=PxswdzoAQvQGkPWUS0AeYk7qhI5OcIZi4EoyckriCiQ=; b=eyaQO3XoQJC0CJQ2LEoHk1Iumkqt80kZxvuK3C3ZuwmdLxQB9WwA+Tzfh+qJwzCDlDAI3c V3L+ARVx77vsqLQ8HF2dn8oE0tsoYQWkr5ZUygs4zTLYMP5wDqolfgD5nhZBQpAELXxAWf tFT5A6KHSkjN6rAJLUCwRDPxk6vtXssomCJKReiXjGWyzaHPAxMSC9sRldc51ffdUlkZ+o txCBM5DUQ+QTwn4Goo5K+lRuyK4XonvfvsSk/kL3XrPfn850KMJpaTFtaiMH5bHC1wbGfk Ob0CLVWlMD+6oAErfqD3w19bVCRg+mYHR5Ta+CMCJlWMtTCygbgGxGp9FyWGjg== Authentication-Results: outgoing_mbo_mout; dkim=none; spf=pass (outgoing_mbo_mout: domain of me@adamthiede.com designates 2001:67c:2050:b231:465::202 as permitted sender) smtp.mailfrom=me@adamthiede.com Message-ID: Date: Mon, 27 Jul 2026 07:52:31 -0500 MIME-Version: 1.0 Subject: Re: [PATCH] drm/mediatek: mtk_dsi: enable hs clock during pre-enable To: Gary Bisson , Thorsten Leemhuis Cc: AngeloGioacchino Del Regno , Chun-Kuang Hu , Esben Haabendal , Philipp Zabel , David Airlie , Simona Vetter , Matthias Brugger , dri-devel@lists.freedesktop.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Linux kernel regressions list References: <20260120-mtkdsi-v1-1-b0f4094f3ac3@gmail.com> <8733xko1ms.fsf@geanix.com> <0f719c00-3cf5-4403-afbf-713b07255981@collabora.com> <65558ccc-4f2c-492d-8c74-627d27dce864@collabora.com> <87h5m0mkca.fsf@geanix.com> Content-Language: en-US From: Adam Thiede Autocrypt: addr=me@adamthiede.com; keydata= xsBNBF+n+90BCAC2ZRLVcvdXDgfY7EppN05eNor3U7/eeiNCCEIWZkYLhikUEP1ReLGBkXpK Pc70hfnKAKkCoth3IwhDty9WXMNU+iLNei4ieb2luW+UqluR6xIUIA+txahMU9YcjVaQTKf/ yZWO4yl6pfBPCxC2UdPZKBAdGoi5NnE0ABFNbhBETQhhBic533lZn33ByupfI3acECnQdjgQ llCUpDbw4I+S/N1iFiEHcbMXH7ZB00e3IYNorZ1E9v7p++5rDY1fQ9gXpieg1vFKwSq1NJWo 9xx336YjaTUbX0EwrdKd9l8AktA3yRjckaK5TAcwSQaDtHvhpbl4ebvPhtwHh699MroXABEB AAHNH0FkYW0gVGhpZWRlIDxtZUBhZGFtdGhpZWRlLmNvbT7CwI4EEwEIADgCGwMFCwkIBwIG FQoJCAsCBBYCAwECHgECF4AWIQQtG9pGQ7sz3tf8M/kC7fV9o/vRzgUCZL1HxQAKCRAC7fV9 o/vRzgyRB/wLqRCvvWhQCMgvzeKvru9wcXquhb77K8H/ByLbfiT8YBuP3lZFVh0IQhgO9Ylk fIoOJE4V+jjxyOnO2d9xjGbvAmmR6yT0gfLzSVWqrC4k+V9MWLv43nrNzxt41dvo5j824FAl X+zaiRZCdO8Jtxg5Elpiop2SKLi1utX1Z8i6YZh+ccJZlchUBAGUTk+D4UjK7vUcjLWT96ya CtdtTfXyw36CvGOPEWfc6++Kkl/5sgej1i7biPYzu/r0vssaQYTXKSrv6Cfa3Maa89ASiTtv q4qmhLnJeCrPxWlRAf6LEizeBEkOasYni2u8sp4wBezEq45Ozu45sfPkqLpPolG7zsBNBF+n +90BCADBRt+vrToRBEG580n77S99qSEkbKD+oJtCVyovnjMNkg0K9UG68LIeCX/ezngiV1M8 JISvw5iFOuUFqGX/1hLl9wgt/YpuIrgWOp8XxkotavTCloLDvQmufJPO1L8bnnA+WgP2YgVZ 5MJTj/t4DI+yQgysEjsH8aurHO2uuqgJE+xK+2dy6Cl/wskuGxObksSPmmFH5PH0Joziwrtl 61ouLE2XwKbkMgIGEKkbFgbfwz3/QuLZGBni+OOtLzXeZ9wNTW/AHUPy6S9U4F+5z6/09fVT tTH0cvrgAGjbASlYx2VqGONXAsxCfjulq6ryJBFlPLp949c/JTTgOojukCSbABEBAAHCwHYE GAEIACACGwwWIQQtG9pGQ7sz3tf8M/kC7fV9o/vRzgUCZL1H0gAKCRAC7fV9o/vRzlamCACs vHw+0heTm+BfC3S8DUST6889gidIIwdqBep1ByzetCph7Bq8Y8BlT5YTX0u/bSKkxCzFgeTm vC341Q09ST2XjLAl1ZTdzGhH9gcgYyOw34pr5fPQRJLB392mPzD8YReRzciNbhWzj+DLgeVe ouyfGajd6jDjkf4FEq+trQLGZhpfsKn3JnDbzBUs945D50l/vz9q/QN3qZO+H4F6g8ZeMnqo FOEFN26xVtdEDr+0DNFsbgKmEzs675kdAY78ZZdbEetX/FSknxJ+FK1ZW3J7Yswwulj34AXP LB49Mk8Ot7fo6mdt0DkV11JS9LmKxKvpY+KTlrKG+i7pVCSZvVUx In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4h7z5h4RMrz8tyC X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260727_055247_471860_AB7050D3 X-CRM114-Status: GOOD ( 23.13 ) 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 On 7/27/26 07:48, Gary Bisson wrote: > Hi Thorsten, > > On Mon, Jul 27, 2026 at 02:28:56PM +0200, Thorsten Leemhuis wrote: >> [top-posting to facilitate] >> >> Gary, Angelo, what's the status here? It looks like this fell through >> the cracks -- or was this issue fixed in between somehow? If yes: great! >> If not: Would be good to finally resolve this, as we are long past "fix >> within a week" rule of thumb from Linus: >> https://www.kernel.org/doc/html/latest/process/handling-regressions.html#on-how-quickly-regressions-should-be-fixed > > Not much happened I'm afraid. The status as I see is: > - this patch is necessary to have TI SN65DSI83 working > - this patch also follows the DRM guidelines saying that HS clock must > be enabled during pre_enable (see previous answer / [1]) > - this patch has been successfully tested against MIPI-DSI panels (by > Angelo) and LVDS panels via TI bridge (by myself) > - Adam reported an issue with another bridge (PS8640) where resume is > broken > - Esben offered a patch to the TI bridge that would fix the issue we > were seeing in the first place. > > But for the last two points, I'm not sure this calls for a revert yet: > - enabling HS clock in pre_enable still is what should be done [1] > - maybe the issue Adam is facing is due to the bridge driver instead as > it could not be reproduced with another setup > - Esben patch would break the SN65DSI83 init sequence, suggesting that > the culprit really is the MIPI bridge for not following the HS clock > requirement in pre_enable instead [2] > > So if we agree on the fact that HS clock must be set during pre_enable > then I don't see a reason to revert that commit. > > Regards, > Gary > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/gpu/drm/drm_bridge.c#n169 > [2] https://patchwork.kernel.org/project/dri-devel/patch/20260711-ti-sn65dsi83-fixes-v1-2-d85eb5342b98@geanix.com/ I'm also happy to try out any patches and report back, too! Just point me to it and let me know which release/RC I should apply it to.