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=-2.4 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT 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 0643CC43387 for ; Sat, 15 Dec 2018 10:12:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C1B7E20645 for ; Sat, 15 Dec 2018 10:12:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730028AbeLOKMY (ORCPT ); Sat, 15 Dec 2018 05:12:24 -0500 Received: from jablonecka.jablonka.cz ([91.219.244.36]:49891 "EHLO jablonecka.jablonka.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729077AbeLOKMX (ORCPT ); Sat, 15 Dec 2018 05:12:23 -0500 Received: from twilight.vojtech.kobylisy.czf (unknown [10.32.148.9]) by jablonecka.jablonka.cz (Postfix mail delivery) with ESMTP id DE0B8603494B; Sat, 15 Dec 2018 11:12:21 +0100 (CET) Received: by twilight.vojtech.kobylisy.czf (Postfix, from userid 1000) id C35B71549C37; Sat, 15 Dec 2018 11:12:21 +0100 (CET) Date: Sat, 15 Dec 2018 11:12:21 +0100 From: Vojtech Pavlik To: Pavel Machek Cc: kernel list , jikos@suse.cz, linux-input@vger.kernel.org, dmitry.torokhov@gmail.com Subject: Re: [rfd] saving old mice -- button glitching/debouncing Message-ID: <20181215101221.GA23879@suse.com> References: <20181214232437.GA8310@amd> <20181215085510.GB12930@suse.com> <20181215094722.GA5804@amd> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181215094722.GA5804@amd> X-Bounce-Cookie: It's a lemon tree, dear Watson! User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Dec 15, 2018 at 10:47:22AM +0100, Pavel Machek wrote: > > > b) would it be acceptable if done properly? (cmd line option to > > > enable, avoiding duplicate/wrong events?) > > > > Well, for one, you shouldn't be using a timer, all the debouncing can be > > done by math on the event timestamps. > > Not... really, right? You need to send an release some time after > button indicates release if bounce did not happen. It is similar to > autorepeat needing a timer. You can send the first release and ignore all presses and releases in a time window after that. > Let me gain some experience with the patch. I don't think hardware > does as heavy debouncing as you describe. Microswitches vibrate significantly when clicked. Without hardware debouncing, you'd have many clicks instead of one even on a new mouse. -- Vojtech Pavlik