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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 7365BEB64D9 for ; Wed, 12 Jul 2023 12:07:26 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5F31410E4EE; Wed, 12 Jul 2023 12:07:25 +0000 (UTC) Received: from mail-io1-xd2b.google.com (mail-io1-xd2b.google.com [IPv6:2607:f8b0:4864:20::d2b]) by gabe.freedesktop.org (Postfix) with ESMTPS id BE6AE10E4EE for ; Wed, 12 Jul 2023 12:07:22 +0000 (UTC) Received: by mail-io1-xd2b.google.com with SMTP id ca18e2360f4ac-783549ef058so307666939f.2 for ; Wed, 12 Jul 2023 05:07:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1689163641; x=1691755641; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=js9A+LroJpKyjly1c+m3wIj1/hOhy81EZTbGk7lLc9w=; b=QJDFf6a2qcjPXjiPm97eZlxkt0nwP+Cy792/OnHUSjEnI5bVgRJOZlFiDEhc9oPi6V 8Ukf3UAhhORVbhHiJLowqUCvznS3tlqmqp+oI2JYlf1FRg/EVkPBXdub7EjPGyE8LFcQ vJY4YUMoSH/dFomzmMcsTFyx0k/FBuivXQWCR9tm6o33eGWo8GmiSO8lRHiZDWPKVnc1 34Kl8LzDooi5FS626w9o36EXvlrHFUt4EOMEg3wWkSxeC7szYcDl6zD0/II0YC5WkiLP eLrjT4FAVw7NGfD33CKrdeg86PxkCNS24anRmf7ctv8V9cgolZXJlFBrEDyeLw+TMIBz Al9w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689163641; x=1691755641; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=js9A+LroJpKyjly1c+m3wIj1/hOhy81EZTbGk7lLc9w=; b=KJkv2KgxLH+YNdhG8694R7016k43JCvIM8oPXpx1c2FFJufYcE1/oFF5pMgh+rZrfQ VDUU6vfzqL5A46TShLJmSwuNAmDCMAWb9x/Lz8HuJPkA5wMVSkj14rfKrSxdHB6YFTWi CiIwwSrETd5mx1bUiCebEL17Ykl39iizebPkoCDgCZjRvonP1F01GsbgdcHiFSwEBNer 27io4ESXnx4KeINOQY1Lg/ABHDzx7doRSJyUiWL2Nb+Qpszm6BpX2XiasgDY1MRvqpiY lS/c1bX9X1qlIZVsc1mKBy0uKn3BSCjL/j/+VeLu2hnts3rtgoki0j8fagDuR0akSDf+ wlCA== X-Gm-Message-State: ABy/qLYGRSCPwJcNhlgVeAuVUXEVsv9Uy+V3jMOm8xMSGWDWWeTpGpyg 1mvB/m/xoKieMnDdsghllpwJfXNwgh8pVU2QIdg= X-Google-Smtp-Source: APBJJlETKzUMF2OAd9kTWv7lkEdSNYU4Mqa9EYSDW3Wz3B8ikNrnIT5lFXObmJx47ZNPP7nh7b1m66J9NjVwYTQm1Zg= X-Received: by 2002:a5d:8848:0:b0:783:606b:740f with SMTP id t8-20020a5d8848000000b00783606b740fmr18734048ios.15.1689163641507; Wed, 12 Jul 2023 05:07:21 -0700 (PDT) MIME-Version: 1.0 References: <20230607151127.1542024-1-pavacic.p@gmail.com> <20230607151127.1542024-4-pavacic.p@gmail.com> <0d43e653-32cd-b25e-40fa-6f0571048467@denx.de> <8b0ae1d1-c769-1f55-0452-4bbc62da133b@denx.de> In-Reply-To: <8b0ae1d1-c769-1f55-0452-4bbc62da133b@denx.de> From: Paulo Pavacic Date: Wed, 12 Jul 2023 14:07:10 +0200 Message-ID: Subject: Re: [PATCH v4 3/3] drm/panel-fannal-c3004: Add fannal c3004 DSI panel To: Marek Vasut Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: neil.armstrong@linaro.org, conor+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, robh+dt@kernel.org, Jagan Teki , sam@ravnborg.org, Maya Matuszczyk Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hello all, sub, 8. srp 2023. u 14:53 Marek Vasut napisao je: > > On 7/7/23 17:26, Paulo Pavacic wrote: > > Hello Marek, > > Hi, > > > =C4=8Det, 6. srp 2023. u 17:26 Marek Vasut napisao je: > >> > >> On 7/6/23 17:18, Paulo Pavacic wrote: > >>> Hello Linus, > >>> > >>> =C4=8Det, 22. lip 2023. u 10:22 Linus Walleij napisao je: > >>>> > >>>> On Wed, Jun 21, 2023 at 5:09=E2=80=AFPM Paulo Pavacic wrote: > >>>> > >>>>> A lot of modifications to st7701 are required. I believe it would > >>>>> result in a driver that doesn't look or work the same. e.g compare > >>>>> delays between initialization sequences of panel-fannal-c3004 and > >>>>> panel-st7701. I think it would be optimal to create st7701s driver = and > >>>>> have special handling for st7701s panels. If there was a flag for > >>>>> whether panel is st7701 or st7701s it would end up looking like a > >>>>> mess. > >>>> > >>>> What matters is if the original authors of the old st7701 driver are > >>>> around and reviewing and testing patches at all. What we need is > >>>> active maintainers. (Added Jagan, Marek & Maya). > >>>> > >>>> I buy the reasoning that the st7701s is perhaps substantially differ= ent > >>>> from st7701. > >>>> > >>>> If st7701s is very different then I suppose it needs a separate driv= er, > >>>> then all we need to to name the driver properly, i.e. > >>>> panel-sitronix-st7701s.c. > >>> > >>> I had in person talk with Paul Kocialkowski and I have concluded that > >>> this is the best solution. > >>> I believe I should rename it to st7701s due to the hardware changes. = I > >>> would like to create V5 patch with driver renamed to st7701s. > >>> Please let me know if you agree / disagree. > >> > >> If I recall it right, the ST7701 and ST7701S are basically the same > >> chip, aren't they ? > > > > I'm currently exploring all the differences. There aren't a lot of > > differences, but there are some. > > So far I can see that default register values are different, new > > previously unused registers are now used and there has been some > > reordering of how info is placed in registers [1] (data bits are in > > different order). Moreover, instructions to some commands have been > > changed and meaning of what data bits mean [2][3]. Also, new features > > have been added [2]; there is now PCLKS 3 for example. > > > > You can see few differences in following images. Same images were > > attached in this mail: > > [1] https://ibb.co/NmgbZmy - GAMACTRL_st7701.png > > [2] https://ibb.co/G79y235 - PCLKS2.png > > Ouch. I wonder if this is still something that can be abstracted out > with some helper accessor functions like: > > if (model =3D=3D ST7701) > write something > else > write the other layout > > Or whether it makes sense to outright have a separate driver. The later > would introduce duplication, but maybe that much duplication is OK. I would like to create new driver because panel-st7701 seems to be outdated and is using non-standard macro (ST7701_WRITE()) and for me it is crashing kernel 5.15. Does anyone have similar issues with it? Br, Paulo