From patchwork Tue May 17 08:56:09 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thierry Reding X-Patchwork-Id: 791032 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.3) with ESMTP id p4H8uIRK027039 for ; Tue, 17 May 2011 08:56:34 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752235Ab1EQI4e (ORCPT ); Tue, 17 May 2011 04:56:34 -0400 Received: from moutng.kundenserver.de ([212.227.17.10]:65484 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752162Ab1EQI4c (ORCPT ); Tue, 17 May 2011 04:56:32 -0400 Received: from localhost (p548E0077.dip0.t-ipconnect.de [84.142.0.119]) by mrelayeu.kundenserver.de (node=mreu4) with ESMTP (Nemesis) id 0LfLHp-1Pu0vP02qP-00p4Hk; Tue, 17 May 2011 10:56:14 +0200 From: Thierry Reding To: linux-input@vger.kernel.org Cc: Dmitry Torokhov , Kwangwoo Lee Subject: [PATCH v2 2/5] tsc2007: Add max_rt parameter to platform data. Date: Tue, 17 May 2011 10:56:09 +0200 Message-Id: <1305622572-3154-2-git-send-email-thierry.reding@avionic-design.de> X-Mailer: git-send-email 1.7.5.1 X-Provags-ID: V02:K0:b1LbEoFVuo62AjgqjE+AmgyvxepVg7bbRFdnc5OW/Cp MxTKg3q97CW8jI6EMHefF+3kYBsvors1xyACthu+StrJvC+1vq Fq0Ah5UDC8yuPNDeAjD9MY7M1TqcZ4fTjVlTU9idT4F41wAHdJ xn/RFei21ytCOp8G3leMPON4lyrq1NtCwpkbJLEhJqPi0CCFdI 483zEYCQL2MFJQsHx+oIiDUiTJDohMl3SPhDXctxSw= Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Tue, 17 May 2011 08:56:34 +0000 (UTC) Finger touch events or very quick stylus events on low-quality panels can cause the tsc2007 to read bogus values. Looking at oscilloscope snapshots, this seems to be caused by the touch event disappearing during the measurements. These bogus values result in misclicks, where the X and Y values deviate from the real position. Most of these misclicks can be filtered out by setting a low enough threshold for the maximum resistance (which is loosely the inverse of the pressure) allowed to consider a set of values valid. Since this behaviour is largely dependent on the type and quality of the panel, this commit introduces the max_rt parameter. The default value is kept at MAX_12BIT. Changes in v2: - Move max_rt parameter to platform data. Cc: Dmitry Torokhov Cc: Kwangwoo Lee Signed-off-by: Thierry Reding --- drivers/input/touchscreen/tsc2007.c | 4 +++- include/linux/i2c/tsc2007.h | 1 + 2 files changed, 4 insertions(+), 1 deletions(-) diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c index df4ae35..8c48a91 100644 --- a/drivers/input/touchscreen/tsc2007.c +++ b/drivers/input/touchscreen/tsc2007.c @@ -75,6 +75,7 @@ struct tsc2007 { u16 model; u16 x_plate_ohms; + u16 max_rt; bool pendown; int irq; @@ -185,7 +186,7 @@ static void tsc2007_work(struct work_struct *work) tsc2007_read_values(ts, &tc); rt = tsc2007_calculate_pressure(ts, &tc); - if (rt > MAX_12BIT) { + if (rt > ts->max_rt) { /* * Sample found inconsistent by debouncing or pressure is * beyond the maximum. Don't report it to user space, @@ -294,6 +295,7 @@ static int __devinit tsc2007_probe(struct i2c_client *client, ts->model = pdata->model; ts->x_plate_ohms = pdata->x_plate_ohms; + ts->max_rt = pdata->max_rt ? : MAX_12BIT; ts->get_pendown_state = pdata->get_pendown_state; ts->clear_penirq = pdata->clear_penirq; diff --git a/include/linux/i2c/tsc2007.h b/include/linux/i2c/tsc2007.h index c6361fb..d95f113 100644 --- a/include/linux/i2c/tsc2007.h +++ b/include/linux/i2c/tsc2007.h @@ -6,6 +6,7 @@ struct tsc2007_platform_data { u16 model; /* 2007. */ u16 x_plate_ohms; + u16 max_rt; /* max. resistance above which samples are ignored */ int (*get_pendown_state)(void); void (*clear_penirq)(void); /* If needed, clear 2nd level