From mboxrd@z Thu Jan 1 00:00:00 1970 From: Henrik Rydberg Subject: Re: [PATCH v2] input: qt602240 - Add ATMEL QT602240 touchscreen driver Date: Mon, 28 Jun 2010 11:10:02 +0200 Message-ID: <4C2866EA.207@euromail.se> References: <1277430882-3685-1-git-send-email-jy0922.shim@samsung.com> <4C24B86E.1030407@euromail.se> <4C283048.1090601@samsung.com> <4C285124.1050201@euromail.se> <4C285AB1.7030301@samsung.com> <4C285E85.6080008@euromail.se> <20100628084212.GE25287@core.coreip.homeip.net> <4C286183.6080304@euromail.se> <20100628090135.GA13523@core.coreip.homeip.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from ch-smtp01.sth.basefarm.net ([80.76.149.212]:44488 "EHLO ch-smtp01.sth.basefarm.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751070Ab0F1JKi (ORCPT ); Mon, 28 Jun 2010 05:10:38 -0400 In-Reply-To: <20100628090135.GA13523@core.coreip.homeip.net> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Dmitry Torokhov Cc: Joonyoung Shim , linux-input@vger.kernel.org, kyungmin.park@samsung.com Dmitry Torokhov wrote: > On Mon, Jun 28, 2010 at 10:46:59AM +0200, Henrik Rydberg wrote: >> Dmitry Torokhov wrote: >>> On Mon, Jun 28, 2010 at 10:34:13AM +0200, Henrik Rydberg wrote: >>>> It is a bit confusing I agree, but the document is correct. The empty >>>> input_mt_sync() is used when there is no data to report, no lifted fingers, >>>> nothing. Just imagine a device which gets polled periodically. >>> If there is no new data to report why we need to call input_mt_sync() at >>> all? You can send input_sync() but input core will filter it out... >>> >> Yep, that is the reason. Admittedly, this is a corner cases that type A does not >> handle very gracefully, but it works. The only device so far where this seems >> useful is for the magic mouse, which does not want to report BTN_TOUCH at all. >> > > So what if we filter everything out? Userspace will never know that we > got an interrupt and will be just fine... > Userspace would still want to know if that last finger stayed on the pad the whole time, or if it was actually removed in between. Henrik