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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED autolearn=ham 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 1722BC43142 for ; Thu, 2 Aug 2018 11:31:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C1537214F1 for ; Thu, 2 Aug 2018 11:31:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=agner.ch header.i=@agner.ch header.b="PPYgGdB/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C1537214F1 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=agner.ch Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732277AbeHBNWT (ORCPT ); Thu, 2 Aug 2018 09:22:19 -0400 Received: from mail.kmu-office.ch ([178.209.48.109]:49288 "EHLO mail.kmu-office.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731083AbeHBNWT (ORCPT ); Thu, 2 Aug 2018 09:22:19 -0400 Received: from webmail.kmu-office.ch (unknown [IPv6:2a02:418:6a02::a3]) by mail.kmu-office.ch (Postfix) with ESMTPSA id BF8C45C08AE; Thu, 2 Aug 2018 13:31:32 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=agner.ch; s=dkim; t=1533209492; 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; bh=yZSBUeD+CS+p5XaryCa+J//p6fEF2SQJ9s4ukuXLGQw=; b=PPYgGdB/NVttiZ2DNbqFQE8Wf0owU6z/VuONKBoKhr6/SpWL5WMKKUZ1KZZNnWQryxjNRS dZhH51lROdeOMugOqQ7RMilwcTMz3YZV47BT4b6s5pVtbR3N823ilNCeADUiocfeWl4N+v UcqvQp0j7W0swlYCjekOLURHpcmXY6g= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Date: Thu, 02 Aug 2018 13:31:32 +0200 From: Stefan Agner To: Dmitry Osipenko Cc: Linus Walleij , Thierry Reding , Jonathan Hunter , Marcel Ziswiler , linux-tegra@vger.kernel.org, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 1/2] pinctrl: tegra: Move drivers registration to arch_init level In-Reply-To: <20180802111144.12512-1-digetx@gmail.com> References: <20180802111144.12512-1-digetx@gmail.com> Message-ID: <20a52a0461e32e776e526171c250551a@agner.ch> X-Sender: stefan@agner.ch User-Agent: Roundcube Webmail/1.3.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02.08.2018 13:11, Dmitry Osipenko wrote: > There is a bug in regards to deferred probing within the drivers core > that causes GPIO-driver to suspend after its users. The bug appears if > GPIO-driver probe is getting deferred, which happens after introducing > dependency on PINCTRL-driver for the GPIO-driver by defining "gpio-ranges" > property in device-tree. The bug in the drivers core is old (more than 4 > years now) and is well known, unfortunately there is no easy fix for it. > The good news is that we can workaround the deferred probe issue by > changing GPIO / PINCTRL drivers registration order and hence by moving > PINCTRL driver registration to the arch_init level and GPIO to the > subsys_init. A while back at least using those init lists were not well received even for GPIO/pinctrl drivers: https://lore.kernel.org/lkml/CACRpkdYk0zW12qNXgOstTLmdVDYacu0Un+8quTN+J_azOic7AA@mail.gmail.com/T/#mf0596982324a6489b5537b0531ac5aed60a316ba I still think we should make an exception for GPIO/pinctrl and use earlier initcalls. Platform GPIO/pinctrl drivers provide basic infrastructure often used by many other drivers, we want to have them loaded early. It avoids unnecessary EPROBE_DEFER and hence probably even boots faster. And in this case it even resolves real world issues. This should definitely go in, at least as a stop gap solution. Acked-by: Stefan Agner -- Stefan > > Signed-off-by: Dmitry Osipenko > --- > drivers/pinctrl/tegra/pinctrl-tegra114.c | 7 ++++++- > drivers/pinctrl/tegra/pinctrl-tegra124.c | 7 ++++++- > drivers/pinctrl/tegra/pinctrl-tegra20.c | 7 ++++++- > drivers/pinctrl/tegra/pinctrl-tegra210.c | 7 ++++++- > drivers/pinctrl/tegra/pinctrl-tegra30.c | 7 ++++++- > 5 files changed, 30 insertions(+), 5 deletions(-) > > diff --git a/drivers/pinctrl/tegra/pinctrl-tegra114.c > b/drivers/pinctrl/tegra/pinctrl-tegra114.c > index 511a8774fd8d..d43c209e9c30 100644 > --- a/drivers/pinctrl/tegra/pinctrl-tegra114.c > +++ b/drivers/pinctrl/tegra/pinctrl-tegra114.c > @@ -1868,4 +1868,9 @@ static struct platform_driver tegra114_pinctrl_driver = { > }, > .probe = tegra114_pinctrl_probe, > }; > -builtin_platform_driver(tegra114_pinctrl_driver); > + > +static int __init tegra114_pinctrl_init(void) > +{ > + return platform_driver_register(&tegra114_pinctrl_driver); > +} > +arch_initcall(tegra114_pinctrl_init); > diff --git a/drivers/pinctrl/tegra/pinctrl-tegra124.c > b/drivers/pinctrl/tegra/pinctrl-tegra124.c > index 57e3cdcf4503..5b07a5834d15 100644 > --- a/drivers/pinctrl/tegra/pinctrl-tegra124.c > +++ b/drivers/pinctrl/tegra/pinctrl-tegra124.c > @@ -2080,4 +2080,9 @@ static struct platform_driver tegra124_pinctrl_driver = { > }, > .probe = tegra124_pinctrl_probe, > }; > -builtin_platform_driver(tegra124_pinctrl_driver); > + > +static int __init tegra124_pinctrl_init(void) > +{ > + return platform_driver_register(&tegra124_pinctrl_driver); > +} > +arch_initcall(tegra124_pinctrl_init); > diff --git a/drivers/pinctrl/tegra/pinctrl-tegra20.c > b/drivers/pinctrl/tegra/pinctrl-tegra20.c > index 624889ed3a9d..1fc82a9576e0 100644 > --- a/drivers/pinctrl/tegra/pinctrl-tegra20.c > +++ b/drivers/pinctrl/tegra/pinctrl-tegra20.c > @@ -2277,4 +2277,9 @@ static struct platform_driver tegra20_pinctrl_driver = { > }, > .probe = tegra20_pinctrl_probe, > }; > -builtin_platform_driver(tegra20_pinctrl_driver); > + > +static int __init tegra20_pinctrl_init(void) > +{ > + return platform_driver_register(&tegra20_pinctrl_driver); > +} > +arch_initcall(tegra20_pinctrl_init); > diff --git a/drivers/pinctrl/tegra/pinctrl-tegra210.c > b/drivers/pinctrl/tegra/pinctrl-tegra210.c > index 0956a1c73391..3e77f5474dd8 100644 > --- a/drivers/pinctrl/tegra/pinctrl-tegra210.c > +++ b/drivers/pinctrl/tegra/pinctrl-tegra210.c > @@ -1582,4 +1582,9 @@ static struct platform_driver tegra210_pinctrl_driver = { > }, > .probe = tegra210_pinctrl_probe, > }; > -builtin_platform_driver(tegra210_pinctrl_driver); > + > +static int __init tegra210_pinctrl_init(void) > +{ > + return platform_driver_register(&tegra210_pinctrl_driver); > +} > +arch_initcall(tegra210_pinctrl_init); > diff --git a/drivers/pinctrl/tegra/pinctrl-tegra30.c > b/drivers/pinctrl/tegra/pinctrl-tegra30.c > index c923ad58af84..10e617003e9c 100644 > --- a/drivers/pinctrl/tegra/pinctrl-tegra30.c > +++ b/drivers/pinctrl/tegra/pinctrl-tegra30.c > @@ -2503,4 +2503,9 @@ static struct platform_driver tegra30_pinctrl_driver = { > }, > .probe = tegra30_pinctrl_probe, > }; > -builtin_platform_driver(tegra30_pinctrl_driver); > + > +static int __init tegra30_pinctrl_init(void) > +{ > + return platform_driver_register(&tegra30_pinctrl_driver); > +} > +arch_initcall(tegra30_pinctrl_init);