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 X-Spam-Level: X-Spam-Status: No, score=-4.1 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9691DC433E0 for ; Tue, 28 Jul 2020 08:09:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6C2AD22B47 for ; Tue, 28 Jul 2020 08:09:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="WfCuIF+N" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726990AbgG1IJq (ORCPT ); Tue, 28 Jul 2020 04:09:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33360 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726032AbgG1IJq (ORCPT ); Tue, 28 Jul 2020 04:09:46 -0400 Received: from mail-lj1-x244.google.com (mail-lj1-x244.google.com [IPv6:2a00:1450:4864:20::244]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0FFA6C0619D2 for ; Tue, 28 Jul 2020 01:09:46 -0700 (PDT) Received: by mail-lj1-x244.google.com with SMTP id h19so20120451ljg.13 for ; Tue, 28 Jul 2020 01:09:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=refqiK2IWlQ3mOTyFeqnVmB/kSEzmm9CW2c4TQojIKs=; b=WfCuIF+N2NmU60NsCa/JwDfZ/2Nv3VdLtl+PsjLet0Nzca6wYbZhf3KLfYAcH+yG6N LaR9+097mHxfUn8gn7Be8CFNnGBmtnA/zxEpDJV/ocsagkHix4jVu3EVG6FrI64jWHYI M+PzasI6lq60ee4UopcVSOqHZ2rmhBcou1LSLGPdsYSqBNegBgB1DWqpolUEmgNk0ju4 CBCGJrhfdr5TCA4JVBROBndTQtCW+wqbRJegLmMyk5uVj7QvYvbvRVhkOWcs5kLLW5ui HOqodhXVOpi6VXsxgX/17k48jouG1wJLBMVXy14roEsN2uWmc+DdP+Mq7Tr986xY3Y5I qdWA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=refqiK2IWlQ3mOTyFeqnVmB/kSEzmm9CW2c4TQojIKs=; b=iOaOuyHSEFDjnF2p9VUk8H2aLLLMdjvXtPmpheWbdNbbd4VP83POIFIsFcSc33J1Ry Puapv047friuGKbHQTwDsQ2RupfWRmQCT8HTk2Tp8dorLuzsKQltaML3V4eNRNJA83vW Ewa5m8DYYOMk32D5apU9DKviRKskGS5l6HXxwmHoEly2/DqUwovXMsx9dXNRzGKA4TcK 6e4alAlx2dksqximPIHYzpeh05WlNE0ePSG+YSaauGDzQ4cq+MJVeGK/emBdVMTHyjoY ZbkUjHoBg+tW19YOcavbOeigsLB5p4Ixmz25BXmqIFfXnszzNQQuHo54hBcG4K7w31Ts XLnQ== X-Gm-Message-State: AOAM5326EdISpKhK54KjM3Z+zWZppdsREfkq7dXWxhd9UvF+hPRBRgpM SzPEkJFCs7mpi/iPHg/WtPQQY8yhBK54yxLyJ7qeOQ== X-Google-Smtp-Source: ABdhPJztqYIekifUAkogxvmP6cFAfSb8mD1OJ06MuDN7GJEQY/Tvu7YCiuhZGtOCnc4NehwkSNKZYCHWWEIIOHWVZ8w= X-Received: by 2002:a05:651c:1291:: with SMTP id 17mr12792312ljc.286.1595923784397; Tue, 28 Jul 2020 01:09:44 -0700 (PDT) MIME-Version: 1.0 References: <1595382353-17486-1-git-send-email-Anson.Huang@nxp.com> In-Reply-To: From: Linus Walleij Date: Tue, 28 Jul 2020 10:09:33 +0200 Message-ID: Subject: Re: [PATCH V2 1/4] gpio: mxc: Support module build To: Arnd Bergmann Cc: Anson Huang , Russell King - ARM Linux , Shawn Guo , Sascha Hauer , Sascha Hauer , Fabio Estevam , Catalin Marinas , Will Deacon , Bartosz Golaszewski , Peter Chen , "oleksandr.suvorov@toradex.com" , Andreas Kemnade , Peng Fan , Hans Verkuil , Olof Johansson , Krzysztof Kozlowski , Alexandre Torgue , Patrice Chotard , Marek Szyprowski , Joel Stanley , Lubomir Rintel , Christian Gmeiner , Bjorn Andersson , Leo Li , Geert Uytterhoeven , "michael@walle.cc" , Linux ARM , "linux-kernel@vger.kernel.org" , "open list:GPIO SUBSYSTEM" , dl-linux-imx Content-Type: text/plain; charset="UTF-8" Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On Mon, Jul 27, 2020 at 1:57 PM Arnd Bergmann wrote: > Overall, my feeling is that making sure all drivers that depend on the pinctrl > driver can deal with deferred probing is a prerequisite before this can be > made a loadable module itself (same for clk, irqchip, etc drivers that others > may rely on). > > I understand that your primary motivation is to fit into Google's GKI framework, > but I think that doing the conversion only partially would neither serve to > improve the kernel nor actually meet the GKI requirements. This has been my worry as well when it comes to these GKI-initiated patches that are flying right now. > Most pinctrl drivers are currently always built-in to work around the > load order dependencies. This of course is a bit of a hack and we'd be > better off if all drivers managed to avoid the dependencies, but this > can also require a lot of work. Several people have argued that it is reasonable to cut corners to achieve the "greater good" of GKI. I try to handle it on a "does the kernel look better after than before" basis, while pushing gently for at least trying to properly modularize the whole thing. It can become pretty hard to test I think. If it is things like GPIO expanders on I2C that can be used by several SoCs I would be more hard on this, on a single SoC not as much. One discussion thread got inflamed because of ARM vs x86 discussions "x86 is better modularized" which is something I want to avoid, it is easy to be modularized when your irqs, clocks, regulators and pins are handled by the BIOS. This is a SoC problem and x86 SoCs with no BIOS, RISCV, ARM and whatever doesn't have a fix-it-all-BIOS have this problem. :/ Yours, Linus Walleij