Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751359AbaLPPa7 (ORCPT ); Tue, 16 Dec 2014 10:30:59 -0500 Received: from mail-wi0-f172.google.com ([209.85.212.172]:61745 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751118AbaLPPa4 (ORCPT ); Tue, 16 Dec 2014 10:30:56 -0500 Date: Tue, 16 Dec 2014 16:30:48 +0100 From: Richard Cochran To: Catalin Crenguta Cc: "Griffis, Brad" , Sebastian Andrzej Siewior , Nicolae Rosia , "R, Vignesh" , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Benoit Cousson , Tony Lindgren , Russell King , Jonathan Cameron , Hartmut Knaack , Dmitry Torokhov , Lee Jones , Lars-Peter Clausen , Peter Meerwald , Samuel Ortiz , "Balbi, Felipe" , Sanjeev Sharma , Paul Gortmaker , Jan Kardell , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-omap@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-iio@vger.kernel.org" , "linux-input@vger.kernel.org" Subject: Re: [PATCH v4 0/6] Touchscreen performance related fixes Message-ID: <20141216153048.GA16981@localhost.localdomain> References: <1415941651-28962-1-git-send-email-vigneshr@ti.com> <20141124115116.GA14997@linutronix.de> <547C3A95.30605@ti.com> <547C3C19.5090501@linutronix.de> <547C42FF.5010700@ti.com> <548A0125.6040708@linutronix.de> <912A29987EAE174BA6CF187D7CDFA9CE26FA135A@DLEE08.ent.ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Dec 16, 2014 at 10:31:47AM +0200, Catalin Crenguta wrote: > > It seems that because the ribbon cable has both the analog and digital > signals, the analog signals are affected by the digital ones (hence > the touchscreen was working OK when the display was disabled). Putting > decoupling capacitors on X+, X-, Y+, Y- reduces the noise and the > false events disappear. IOW, the root cause is a design flaw in the BB-View 4.3 Cape? Thanks, Richard -- 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/