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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, 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 8E6F7C43381 for ; Mon, 11 Jan 2021 13:40:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5E466221EC for ; Mon, 11 Jan 2021 13:40:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387520AbhAKNko (ORCPT ); Mon, 11 Jan 2021 08:40:44 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731984AbhAKNkl (ORCPT ); Mon, 11 Jan 2021 08:40:41 -0500 Received: from mail-io1-xd31.google.com (mail-io1-xd31.google.com [IPv6:2607:f8b0:4864:20::d31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4A6FCC061786; Mon, 11 Jan 2021 05:40:01 -0800 (PST) Received: by mail-io1-xd31.google.com with SMTP id 81so17761534ioc.13; Mon, 11 Jan 2021 05:40:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=VPX+TWLUVWMLDjFiSnhOZGL+SWYosAkfqkHnqdSxUAM=; b=oYpWOHIwy6XftMFufPxgO9fchZbGj2sitlgT6yrncOYW3o+rDnEaoDdEBgXbnIkNeX BRgMVzfxXtPehTLtxH6/A+/pCGEJ3rhhXAiCTmRByGxtCcl8HuLLDc4BXZpAV55H3biZ 0yDuJ/sOHEfW0HPXS5Fkcy+xtw+eO8Vz+ABu8n7XEudo17TUNCRfI2C5ZA6PpHF0HWLe Lx7Pjc40cr4XA321nE1pFq1IE4Pg7cHaco2k4hd0nh2MkbN3i8tPv7ypcjFqWMR7xBRv c3Bd9zDm7FaaHKwWj0GVydeK7Us4jjDSjh2RO7254w2P/sPOk9WCkIF5XTrXgUCTwGu8 z98g== 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=VPX+TWLUVWMLDjFiSnhOZGL+SWYosAkfqkHnqdSxUAM=; b=ExQYTm2mjN9pDwKXVoFR7DGfblCYkkdZkc4f9UaQ7+fkxpHeXRVhVMvENp7hSN/Y8S YqUc8vgAPYotsIiKOg9iFsSYqxpYIKm2wiIjaRdiwANVdVXqHXXTN59t82ZfYmaieIEj K4mmHeSN2h65tGQV/b5UFf1KXRowRtJBN0ctomcpdecmkzITic1BnaSv4lxEmltu+ybB RK0PngNCKnciaKKu1mHbyZpj4TojRH7Tbz9BpHHvpp3AOvFvquPT/SUoS0rVEMfmFmhE oyExkAKPDRtAfPagJWpA/d6ZicvTE9R4tl9Wr9+oy/yr7c3onK+sHs4vTWTST+gnkJQ5 T2RA== X-Gm-Message-State: AOAM532w/nemwmpkAXu4NksVBYPXr34KoLkKWZcFfvLtKUYx0u7WCE9r pLCxSViWjNhEen45aRq3XBPuJTLt7bj0QUMNKwU= X-Google-Smtp-Source: ABdhPJxdIHd1jmADjrtYp3Zsp0l/yfn12bjpz+qSZpWV+XVteUVCntZjcfHonB6Q9MK8aoe7wB6LwfSgeU+sRkaghGs= X-Received: by 2002:a02:c8c7:: with SMTP id q7mr14527159jao.7.1610372400687; Mon, 11 Jan 2021 05:40:00 -0800 (PST) MIME-Version: 1.0 References: <20210111054428.3273-1-dqfext@gmail.com> <20210111054428.3273-3-dqfext@gmail.com> <20210111110407.GR1551@shell.armlinux.org.uk> In-Reply-To: <20210111110407.GR1551@shell.armlinux.org.uk> From: DENG Qingfang Date: Mon, 11 Jan 2021 21:40:00 +0800 Message-ID: Subject: Re: [PATCH net-next 2/2] drivers: net: dsa: mt7530: MT7530 optional GPIO support To: Russell King - ARM Linux admin Cc: Andrew Lunn , Vivien Didelot , Florian Fainelli , Vladimir Oltean , "David S. Miller" , Jakub Kicinski , Rob Herring , Matthias Brugger , Sean Wang , Landen Chao , Philipp Zabel , netdev , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, "moderated list:ARM/Mediatek SoC support" , linux-kernel@vger.kernel.org, =?UTF-8?Q?Ren=C3=A9_van_Dorst?= , Frank Wunderlich Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Jan 11, 2021 at 7:04 PM Russell King - ARM Linux admin wrote: > > FYI, Documentation/driver-api/gpio/consumer.rst says: > > For output GPIOs, the value provided becomes the initial output value. > This helps avoid signal glitching during system startup. > > Setting the pin to be an output, and then setting its initial value > does not avoid the glitch. You may wish to investigate whether you > can set the value before setting the pin as an output to avoid this > issue. > So, setting the Output Enable bit _after_ setting the direction and initial value should avoid this issue. Right?