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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1D161C77B73 for ; Tue, 30 May 2023 10:53:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229846AbjE3Kxw (ORCPT ); Tue, 30 May 2023 06:53:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43834 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229752AbjE3Kxv (ORCPT ); Tue, 30 May 2023 06:53:51 -0400 Received: from fgw22-7.mail.saunalahti.fi (fgw22-7.mail.saunalahti.fi [62.142.5.83]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 841A5A0 for ; Tue, 30 May 2023 03:53:50 -0700 (PDT) Received: from localhost (88-113-26-95.elisa-laajakaista.fi [88.113.26.95]) by fgw22.mail.saunalahti.fi (Halon) with ESMTP id 412208c1-fed8-11ed-a9de-005056bdf889; Tue, 30 May 2023 13:53:48 +0300 (EEST) From: andy.shevchenko@gmail.com Date: Tue, 30 May 2023 13:53:47 +0300 To: "xingtong.wu" Cc: andy.shevchenko@gmail.com, simon.guinot@sequanux.org, Linus Walleij , brgl@bgdev.pl, linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, henning.schild@siemens.com, xingtong.wu@siemens.com Subject: Re: [PATCH v2 1/1] gpio-f7188x: fix base values conflicts with other gpio pins Message-ID: References: <20230529025011.2806-1-xingtong_wu@163.com> <20230529025011.2806-2-xingtong_wu@163.com> <5428dcc3-bcaf-2fff-59db-62d3b3b45d17@163.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <5428dcc3-bcaf-2fff-59db-62d3b3b45d17@163.com> Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org Tue, May 30, 2023 at 02:27:09PM +0800, xingtong.wu kirjoitti: > On 2023/5/30 06:24, andy.shevchenko@gmail.com wrote: > > Mon, May 29, 2023 at 03:54:36PM +0200, simon.guinot@sequanux.org kirjoitti: > >> On Mon, May 29, 2023 at 03:03:28PM +0200, Linus Walleij wrote: > >>> On Mon, May 29, 2023 at 2:27 PM wrote: > >>> > >>>> It would be nice if a pin number found in the device datasheet could > >>>> still be converted into a Linux GPIO number by adding the base of the > >>>> first bank. > >>> > >>> We actively discourage this kind of mapping because of reasons stated > >>> in drivers/gpio/TODO: we want dynamic number allocation to be the > >>> norm. > >> > >> Sure but it would be nice to have a dynamic base applied to a controller > >> (and not to each chip of this controller), and to respect the interval > >> between the chips (as stated in the controllers datasheets). > > > > What you want is against the architecture. To fix this, you might change > > the architecture of the driver to have one chip for the controller, but > > it's quite questionable change. Also how can you guarantee ordering of > > the enumeration? You probably need to *disable* SMP on the boot time. > > This will still be fragile as long as GPIO chip can be unbound at run > > time. Order can be changed. > > > > So, the patch is good and the correct way to go. > > > > P.S. The root cause is that hardware engineers and documentation writers > > do not consider their hardware in the multi-tasking, multi-user general > > purpose operating system, such as Linux. I believe the ideal fix is to fix the > > documentation (datasheet). > > Thanks for your review. > > The direct reason of this patch is that when "modprobe gpio-f7188x", > it conflicts with INT34C6. I met this issue on an older kernel, but > could not remember which version exactly. This is interesting. But what I have noticed the v6.3.2 missing this https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/gpio/gpiolib.c?id=7dd3d9bd873f138675cb727eaa51a498d99f0e89 change. Can you apply and retest? If this does not help, please share more details, exact steps of reproducing the issue, including respective `dmesg` output, etc. (maybe via creating a kernel bugzilla report). > The error message is as the link below: > https://elixir.bootlin.com/linux/v6.3.2/source/drivers/gpio/gpiolib.c#L798 -- With Best Regards, Andy Shevchenko