From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755572AbZCCKfV (ORCPT ); Tue, 3 Mar 2009 05:35:21 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751263AbZCCKfH (ORCPT ); Tue, 3 Mar 2009 05:35:07 -0500 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:60001 "EHLO opensource2.wolfsonmicro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750901AbZCCKfG (ORCPT ); Tue, 3 Mar 2009 05:35:06 -0500 Date: Tue, 3 Mar 2009 10:35:02 +0000 From: Mark Brown To: Dmitry Torokhov Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, Hans-Christian Egtvedt Subject: Re: [PATCH 2/2] Input: add wm97xx accelerated driver for AVR32 AT32AP700X microprocessors Message-ID: <20090303103501.GA19086@rakim.wolfsonmicro.main> References: <1236000228-13025-1-git-send-email-broonie@opensource.wolfsonmicro.com> <1236000228-13025-2-git-send-email-broonie@opensource.wolfsonmicro.com> <20090303091322.GA14557@dtor-d630.eng.vmware.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090303091322.GA14557@dtor-d630.eng.vmware.com> X-Cookie: TAILFINS!! ... click ... User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 03, 2009 at 01:13:23AM -0800, Dmitry Torokhov wrote: > Hi Mark, This is actually Hans-Christian's patch but here goes... > > + if (!pressure && source == WM97XX_ADCSEL_Y) { > > + input_report_abs(wm->input_dev, ABS_X, at32_wm97xx->x); > > + input_report_abs(wm->input_dev, ABS_Y, at32_wm97xx->y); > > + input_report_abs(wm->input_dev, ABS_PRESSURE, pen_down); > Please do not report pressure (and don't advertise ABS_PRESSURE) if you don't > actually read it. I have seen a follow-up patch that adds BTN_TOUCH that should > work just fine here. The usage below is good since there you actually do provide > true pressure readings. BTW, why would one not want pressure readings? These parts are usually deployed in embedded systems where performance is sufficiently tightly constrained that the additional work involved in taking pressure measurements is noticable. This is mostly the case where PIO is used but users have reported problems even when using DMA so idiomatically WM97xx drivers provide the option.