Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757718AbZFYPGZ (ORCPT ); Thu, 25 Jun 2009 11:06:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756889AbZFYPGR (ORCPT ); Thu, 25 Jun 2009 11:06:17 -0400 Received: from smtp.nokia.com ([192.100.122.230]:39745 "EHLO mgw-mx03.nokia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755615AbZFYPGQ (ORCPT ); Thu, 25 Jun 2009 11:06:16 -0400 Subject: Re: [PATCH]input: Change timer function to workqueue for gpio_keys driver From: Jani Nikula To: ext Alek Du Cc: LKML , Trilok Soni , "linux-input@vger.kernel.org" , Dmitry Torokhov , "ben-linux@fluff.org" In-Reply-To: <1245941565.20530.134.camel@jani-desktop> References: <20090608152420.0e76c302@dxy.sh.intel.com> <5d5443650906121040n3f36c99eka01f5eb5274ee6ff@mail.gmail.com> <359ed6810906250329x70cf380cy278f23e3ebc6a829@mail.gmail.com> <20090625210642.432e08a5@dxy.sh.intel.com> <1245936693.20530.107.camel@jani-desktop> <20090625220826.1fa7413e@dxy.sh.intel.com> <1245941565.20530.134.camel@jani-desktop> Content-Type: text/plain Date: Thu, 25 Jun 2009 18:05:55 +0300 Message-Id: <1245942355.20530.141.camel@jani-desktop> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 25 Jun 2009 15:06:01.0990 (UTC) FILETIME=[7436E260:01C9F5A6] X-Nokia-AV: Clean Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1383 Lines: 37 On Thu, 2009-06-25 at 16:52 +0200, Jani Nikula wrote: > On Thu, 2009-06-25 at 16:08 +0200, ext Alek Du wrote: > > If you schedule the timer when you decide it "stabilized", the final gpio_get_value() > > could still return 0 in the timer handler, if the key released at that time. So your previous > > "stabilized" state is useless. > > True, gpio_keys_report_event should also compare the value to the > previous state and bail out if it's unchanged. Something along the lines > of: > > @@ -46,6 +46,10 @@ static void gpio_keys_report_event(struct work_struct *work) > unsigned int type = button->type ?: EV_KEY; > int state = (gpio_get_value(button->gpio) ? 1 : 0) ^ button->active_low; > > + if (state == bdata->state) > + return; > + bdata->state = state; Actually scrap that, the input layer already ignores events with no state changes, right? > Debouncing should also completely ignore a single spike shorter than > debounce_interval. Admittedly gpio-keys was flawed, but please consider > a change like above which should fix that. Same here, gpio-keys did ignore spikes shorter than debounce_interval. BR, Jani. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/