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=-5.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 98505C433DF for ; Mon, 6 Jul 2020 18:03:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 724EB206DF for ; Mon, 6 Jul 2020 18:03:52 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=broadcom.com header.i=@broadcom.com header.b="ZQQk4dLt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729657AbgGFSDw (ORCPT ); Mon, 6 Jul 2020 14:03:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60998 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729648AbgGFSDv (ORCPT ); Mon, 6 Jul 2020 14:03:51 -0400 Received: from mail-wm1-x343.google.com (mail-wm1-x343.google.com [IPv6:2a00:1450:4864:20::343]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6B46CC061755 for ; Mon, 6 Jul 2020 11:03:51 -0700 (PDT) Received: by mail-wm1-x343.google.com with SMTP id 22so40269144wmg.1 for ; Mon, 06 Jul 2020 11:03:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=1r9nQdWAuC8N3L1BUVcnwpS3LGqvBj+wWQMPJCqLtvo=; b=ZQQk4dLtYx4rXkZhrV/UnqXCtRf6fQ6sUIDr2YabKGUhR3TxA0ZyoT+fKfNxfCeS5y 7aOUhd8r/us9cpKZjarVN6ikyylNM1kju32WZAhE3M1azxKGbrY3FVWjpzhoRKVXkH+n UMUo4V/JgYe4Za1zs45PoQnm0h8bH6oHoi49Q= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=1r9nQdWAuC8N3L1BUVcnwpS3LGqvBj+wWQMPJCqLtvo=; b=KdyAfe+QKOwqfiBRuT4LAj56TbFdV3Ljf53SytMmFMOfQ2EwoSiZqmjqVL1z8wPqIh +mZKN+DvURjwtdxokL0Frr7UljdFiSZ6/tu12IpVSdtB2/4Xl+tY6MYl8m5jspUFpA/Q 3t7W5RLZPf/LqBJqazKsIGoUOO7fEQQN8Nnt9A9VMmxmF2XRBzOL4gqVRL8OVhrjqMwo 6gzn3KBelAOT72ejmOEQCHLWznlFJ96hVvOznmqZVj45H5MKkpSCTH+TWLVIzggKBNOg 8pj1/nlWgV5h3w+qH91gInkO1yf9XAft+gT8m18Ade41pnL0WJHtnTCyogFF/yyW+9kh N+Qg== X-Gm-Message-State: AOAM530p64EKZK1D9Scv4Nqu/TH4U6ZDwbaf6e22qfEbNxI6DA3PdgUO BjUnVQ0G2WXA1vvFicpqe2u4ag== X-Google-Smtp-Source: ABdhPJxIvXroKVjZ+FrZo4o+fwxqV9fn7/P/NvJsQUHYWvoNqS6xwkV4tFfScORJId5peKPFn3S9WQ== X-Received: by 2002:a1c:32c4:: with SMTP id y187mr382139wmy.79.1594058629837; Mon, 06 Jul 2020 11:03:49 -0700 (PDT) Received: from [192.168.1.201] (d162-156-48-252.bchsia.telus.net. [162.156.48.252]) by smtp.gmail.com with ESMTPSA id x5sm314958wmg.2.2020.07.06.11.03.47 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 06 Jul 2020 11:03:49 -0700 (PDT) Subject: Re: [PATCH] pinctrl: initialise nsp-mux earlier. To: Florian Fainelli , Mark Tomlinson , "bcm-kernel-feedback-list@broadcom.com" , "linux-gpio@vger.kernel.org" , "linus.walleij@linaro.org" , "sbranden@broadcom.com" , "rjui@broadcom.com" Cc: "linux-kernel@vger.kernel.org" References: <20200630212958.24030-1-mark.tomlinson@alliedtelesis.co.nz> <760595a8cdfeb0156d5180ecaeb2ee4487f50cc7.camel@alliedtelesis.co.nz> <86c009a8-05c4-40a3-daef-6d9e848642a3@gmail.com> From: Ray Jui Message-ID: Date: Mon, 6 Jul 2020 11:03:45 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.9.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-gpio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org On 6/30/2020 9:44 PM, Florian Fainelli wrote: > > > On 6/30/2020 9:37 PM, Mark Tomlinson wrote: >> On Tue, 2020-06-30 at 20:14 -0700, Florian Fainelli wrote: >>> Sorry, it looks like I made a mistake in my testing (or I was lucky), >>>> and this patch doesn't fix the issue. What is happening is: >>>> 1) nsp-pinmux driver is registered (arch_initcall). >>>> 2) nsp-gpio-a driver is registered (arch_initcall_sync). >>>> 3) of_platform_default_populate_init() is called (also at level >>>> arch_initcall_sync), which scans the device tree, adds the nsp-gpio-a >>>> device, runs its probe, and this returns -EPROBE_DEFER with the error >>>> message. >>>> 4) Only now nsp-pinmux device is probed. >>>> >>>> Changing the 'arch_initcall_sync' to 'device_initcall' in nsp-gpio-a >>>> ensures that the pinmux is probed first since >>>> of_platform_default_populate_init() will be called between the two >>>> register calls, and the error goes away. Is this change acceptable as a >>>> solution? >>> >>> If probe deferral did not work, certainly but it sounds like this is >>> being done just for the sake of eliminating a round of probe deferral, >>> is there a functional problem this is fixing? >> >> No, I'm just trying to prevent an "error" message appearing in syslog. >> >>>> The actual error message in syslog is: >>>> >>>> kern.err kernel: gpiochip_add_data_with_key: GPIOs 480..511 >>>> (18000020.gpio) failed to register, -517 >>>> >>>> So an end user sees "err" and "failed", and doesn't know what "-517" >>>> means. >>> >>> How about this instead: >>> >>> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c >>> index 4fa075d49fbc..10d9d0c17c9e 100644 >>> --- a/drivers/gpio/gpiolib.c >>> +++ b/drivers/gpio/gpiolib.c >>> @@ -1818,9 +1818,10 @@ int gpiochip_add_data_with_key(struct gpio_chip >>> *gc, void *data, >>> ida_simple_remove(&gpio_ida, gdev->id); >>> err_free_gdev: >>> /* failures here can mean systems won't boot... */ >>> - pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__, >>> - gdev->base, gdev->base + gdev->ngpio - 1, >>> - gc->label ? : "generic", ret); >>> + if (ret != -EPROBE_DEFER) >>> + pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", >>> + __func__, gdev->base, gdev->base + gdev->ngpio - 1, >>> + gc->label ? : "generic", ret); >>> kfree(gdev); >>> return ret; >>> } >>> >> That was one of my thoughts too. I found someone had tried that >> earlier, but it was rejected: >> >> >> https://patchwork.ozlabs.org/project/linux-gpio/patch/1516566774-1786-1-git-send-email-david@lechnology.com/ > > clk or reset APIs do not complain loudly on EPROBE_DEFER, it seems to me > that GPIO should follow here. Also, it does look like Linus was in > agreement in the end, not sure why it was not applied though. > I think either we silently drop this or we explicitly make it obvious that it failed due to EPROBE_DEFER. Both seem acceptable to me. Thanks! Ray