From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH v2] input: qt602240 - Add ATMEL QT602240 touchscreen driver Date: Mon, 28 Jun 2010 02:01:35 -0700 Message-ID: <20100628090135.GA13523@core.coreip.homeip.net> 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> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-pv0-f174.google.com ([74.125.83.174]:48081 "EHLO mail-pv0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755046Ab0F1JBo (ORCPT ); Mon, 28 Jun 2010 05:01:44 -0400 Received: by pvg2 with SMTP id 2so1802787pvg.19 for ; Mon, 28 Jun 2010 02:01:43 -0700 (PDT) Content-Disposition: inline In-Reply-To: <4C286183.6080304@euromail.se> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Henrik Rydberg Cc: Joonyoung Shim , linux-input@vger.kernel.org, kyungmin.park@samsung.com 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... -- Dmitry