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=-2.8 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 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 6EE4AC43331 for ; Fri, 5 Mar 2021 18:36:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 57B266509A for ; Fri, 5 Mar 2021 18:36:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230215AbhCESft (ORCPT ); Fri, 5 Mar 2021 13:35:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230213AbhCESfb (ORCPT ); Fri, 5 Mar 2021 13:35:31 -0500 Received: from mail-pg1-x52c.google.com (mail-pg1-x52c.google.com [IPv6:2607:f8b0:4864:20::52c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD973C061574; Fri, 5 Mar 2021 10:35:31 -0800 (PST) Received: by mail-pg1-x52c.google.com with SMTP id t26so1953571pgv.3; Fri, 05 Mar 2021 10:35:31 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=bebTZOBS90Mn7EMR9IqSfE9satt6qw7eQpkaCcjmPC4=; b=QBsRsPbSSqwPsOQf7nmJQt+eB1kupI6HHagrsUgxHLWyzMb4H/9DN8jx1PpFPjB1zu epRM30Gu/7qLI09d+hqPh7/hO0ZfzDVBpwsD6s7V5dyhV5mN4s5CkXnDo4Rb/Hyc8QRi QDZa9bIovsZfiy+oo7pZNmocVb8gFGmsu3FUdTnGnxFam/ZsJK6F8kHe0vHOE6kLxvaS LMh4tyY8p1loEjDHGVok8pm1TFNhhboaw45uQUru+T6Gp1uEmybfoNlQKgYEg6AtCr7F y/OjUBgDoONigOJpLBhUgo0mC4INLLNE1E708VaEkV/VcXYNjnNq+NR01WFlK1UiAVrw 6QLA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=bebTZOBS90Mn7EMR9IqSfE9satt6qw7eQpkaCcjmPC4=; b=c7DsDvdPOCtMHKX5Ozp31z+R+mtdFvOge+jK0pmbVNQj8lzARsRDQ6d5z1an1+4UIB AgOZ7gWI6ntrzFQCPfeN+4BemgWL13QTrvaPwHHxf2v5ku4SwtvrXmmQiA+7TIrkb/Nl 3bGq2wv+aT+GqyckYwrEoB7uZtIit4W0GGb3UdUPgRjZ0aRedvn0Ou35hQcHo0xPsEl+ xq1yKAUri4/BCwmez2b67YFxfLnNyvnNNDEOOx0WRoHxiWg9P33WScivaTNkQ7wyUQ8E Wxn+N0N3tQBkI+8xY33ryWBKgbFFJ0vsLwAqAuUA9wnL8cyx+WWBsvnj8WbPMkyrj6Pw XSkA== X-Gm-Message-State: AOAM530X+nWc0DWy8HWxQwKse5oorR2l9FBLP1Tp7KUv3PgX0pqmdGAt Xxx54krOgr2ckpDPgbGJEgg= X-Google-Smtp-Source: ABdhPJxb0ulaBrIkxI29f08vnaSprwKYVBnjN0VJdc3afyg0naid8D3i1/g1tns/y3E1VWs9Bn+7TA== X-Received: by 2002:a62:1896:0:b029:197:491c:be38 with SMTP id 144-20020a6218960000b0290197491cbe38mr10147888pfy.15.1614969331120; Fri, 05 Mar 2021 10:35:31 -0800 (PST) Received: from google.com ([2620:15c:202:201:70ea:1e11:c25c:35fe]) by smtp.gmail.com with ESMTPSA id a3sm3122976pfi.206.2021.03.05.10.35.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 05 Mar 2021 10:35:29 -0800 (PST) Date: Fri, 5 Mar 2021 10:35:24 -0800 From: Dmitry Torokhov To: Paul Cercueil Cc: od@zcrc.me, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 3/3] input: gpio-keys: Use hrtimer for software debounce Message-ID: References: <20210305170111.214782-1-paul@crapouillou.net> <20210305170111.214782-3-paul@crapouillou.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210305170111.214782-3-paul@crapouillou.net> Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org Hi Paul, On Fri, Mar 05, 2021 at 05:01:11PM +0000, Paul Cercueil wrote: > -static void gpio_keys_gpio_work_func(struct work_struct *work) > +static enum hrtimer_restart gpio_keys_debounce_timer(struct hrtimer *t) > { > - struct gpio_button_data *bdata = > - container_of(work, struct gpio_button_data, work.work); > + struct gpio_button_data *bdata = container_of(t, > + struct gpio_button_data, > + debounce_timer); > > gpio_keys_gpio_report_event(bdata); I am not sure how this works. As far as I know, even HRTIMER_MODE_REL_SOFT do not allow sleeping in the timer handlers, and gpio_keys_gpio_report_event() use sleeping variant of GPIOD API (and that is not going to change). It seems to me that if you want to use software debounce in gpio keys driver you need to set up sufficiently high HZ for your system. Maybe we could thrown a warning when we see low debounce delay and low HZ to alert system developer. Thanks. -- Dmitry