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 5AB49D116F6 for ; Tue, 2 Dec 2025 11:52:14 +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=oxcXotKddeH8R9jfCsWwWBapnPOHw/RY4rId/Wzzd1s=; b=nT2rcAFG+CRPvGqfMi728ri1+k vcbOdENoWeSgK+BuYCwkeDUEO8wTPKfQxhS5/Ws3o7UQX7UWCeXjfk95pVN9HfBH6hvjeuN4RGS9S 4+7KTQc4fzTqxNvTh54qhgXvi/xKJolMLLn7fNHecrS+nkgpBKtzBGz4hRVjHIE7v1ohkbD5T6yEz D7MkY0DPNub3dAw5Hq5lkJopzYislXobBAJxFzkzDDk1xlGXDg0sm+Q2Bu5ED6rvBKciKY/ZcKNFG wzN9ayQzGF/g867GrszOxFXFM4resxpdJk90qTp980s2h9LRPz73TgIq8HeHk1kheMjO+kOf/hlqw R+daGFFQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vQOvS-00000005L5T-44t0; Tue, 02 Dec 2025 11:52:10 +0000 Received: from perceval.ideasonboard.com ([213.167.242.64]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vQOvQ-00000005L53-1TT4 for linux-arm-kernel@lists.infradead.org; Tue, 02 Dec 2025 11:52:10 +0000 Received: from [192.168.88.20] (91-158-153-178.elisa-laajakaista.fi [91.158.153.178]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 442AE16A; Tue, 2 Dec 2025 12:49:49 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1764676190; bh=vcpCTg0wpMBBIdr8xrC7o97iEYNz6S+U+iHa72fxOsQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=pew/nz/9erz0jniUczc0Vo5JzbSbEzuA456Dp6BUQ4YldSqYW75EjlBKtmyrE+seB Rv+h8iinBEAyGcBtcmnBhhTA8ie6TTkE1OSIN+GkNywoKvhsB/l4RhHyNX/1yDunZu 97b6Zjp3h4YGPLRBEb11/oei56Uy2Z7Ija+hsV5Y= Message-ID: <1d9a9269-bfda-4d43-938b-2df6b82b9369@ideasonboard.com> Date: Tue, 2 Dec 2025 13:51:59 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 05/21] ARM: dts: omap: Bind panel to panel-dpi instead of ti,tilcdc,panel driver To: Kory Maincent , Krzysztof Kozlowski Cc: Markus Schneider-Pargmann , Luca Ceresoli , Louis Chauvet , Thomas Petazzoni , Miguel Gazquez , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-omap@vger.kernel.org, Jyri Sarha , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Russell King , Bartosz Golaszewski , Tony Lindgren , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec References: <20251126-feature_tilcdc-v1-0-49b9ef2e3aa0@bootlin.com> <20251126-feature_tilcdc-v1-5-49b9ef2e3aa0@bootlin.com> <96b1b7bf-ddbe-4213-a201-dc89cf2998dd@ideasonboard.com> <3bc5bf92-05c3-4841-ab28-9bab2bb31cd5@kernel.org> <20251202104244.59a9e83d@kmaincent-XPS-13-7390> <20251202114416.09624a4b@kmaincent-XPS-13-7390> <94e254fa-289d-41ed-909f-1742cfbb2690@kernel.org> <20251202121856.0da62885@kmaincent-XPS-13-7390> From: Tomi Valkeinen Content-Language: en-US Autocrypt: addr=tomi.valkeinen@ideasonboard.com; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251202_035209_455902_8534696A X-CRM114-Status: GOOD ( 32.81 ) 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 Kory, On 02/12/2025 13:18, Kory Maincent wrote: > On Tue, 2 Dec 2025 11:47:40 +0100 > Krzysztof Kozlowski wrote: > >> On 02/12/2025 11:44, Kory Maincent wrote: >>> On Tue, 2 Dec 2025 11:28:55 +0100 >>> Krzysztof Kozlowski wrote: >>> >>>> On 02/12/2025 10:42, Kory Maincent wrote: >>>>> >>>>>> Stuffing DTS change in the middle of the driver change tries to hide >>>>>> impact, which is not nice on its own. >>>>> >>>>> As it needs driver change before the removal for not breaking things it >>>>> can't be done at the beginning of the series. >>>> >>>> And that is the problem which should stop you there and rethink how to >>>> organize it without impacting users. DTS cannot go via DRM. If that was >>>> your intention, that's my: >>>> >>>> NAK >>> >>> My intention was to raise discussion over the ugly and legacy tilcdc-panel >>> binding and what to do with it. But it seems you don't want to, that's a >>> shame. >> >> I don't see how you get to these conclusions. I comment that putting >> here DTS in the middle without any explanation of the impact is not >> correct and this one alone I disagree with. > > Because you didn't replied to the first line of my answer: > "Yes, I know this but I still wanted to try and begin a discussion on this, as I > really thought it is not a good idea to add and maintain an new non-standard > panel driver solely for this tilcdc panel binding." > > But indeed you are right, I should have put more explanation on why there is DTS > and binding change in the middle of the series. Sorry for that. > >> From that you claim I don't want to fix things... >> >> DTS cannot go to drm, which means you either need to separate the change >> and make entire work bisectable and backwards compatible for some time >> OR at least document clearly the impact as we always ask. > > The thing is, if I split it, it has to be in 3. One for the of DRM bus flags > support, a second for the the devicetree and binding change and a third for the > whole tilcdc and tda998x cleaning stuff. I think I will go for one series, with > better documentation. > > Now, what is your point of view on my question. Will you nak any binding > removal even if the binding is ugly and legacy and imply maintaining an > non-standard tilcdc panel driver? I know it breaks DTB compatibility but there > is several argument to not keep it. See patch 6. The binding being ugly and having to maintain non-standard tilcdc panel driver may be nice things for us, the users don't care. The users care if their board no longer works. And how does this sync with u-boot? It also has code for at least for a few of these boards. Are there even users for these boards? If not, maybe they can be just removed? I'm personally not familiar with these boards, so I have no idea of their age or distribution. One trick that can be done is to modify the loaded DTB at boot time, detecting the old format, converting it to the new one, so that when the drivers are probed they only see the new DTB. Tomi