From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Cochran <richardcochran-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH v4 0/6] Touchscreen performance related fixes
Date: Tue, 16 Dec 2014 16:30:48 +0100
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To: Catalin Crenguta <catalin.crenguta-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: "Griffis, Brad" <bgriffis-l0cyMroinI0@public.gmane.org>, Sebastian Andrzej Siewior <bigeasy-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>, Nicolae Rosia <nicolae.rosia-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, "R, Vignesh" <vigneshr-l0cyMroinI0@public.gmane.org>, Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Pawel Moll <pawel.moll-5wv7dgnIgG8@public.gmane.org>, Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>, Ian Campbell <ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org>, Kumar Gala <galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org>, Benoit Cousson <bcousson-rdvid1DuHRBWk0Htik3J/w@public.gmane.org>, Tony Lindgren <tony-4v6yS6AI5VpBDgjK7y7TUQ@public.gmane.org>, Russell King <linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org>, Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, Hartmut Knaack <knaack.h-Mmb7MZpHnFY@public.gmane.org>, Dmitry Torokhov <dmitry.torokhov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, Lars-Peter Clausen <lars-Qo5EllUWu/uELgA04lAiVw@public.gmane.org>, Peter Meerwald <pmeerw-jW+XmwGofnusTnJN9+BGXg@public.gmane.org>, Samuel Ortiz <sameo-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>, "Balbi, Felipe" <balbi-l0cyMroinI0@public.gmane.org>, Sanjeev Sharma <sanjeev_sharma-nmGgyN9QBj3QT0dZR+AlfA@public.gmane.org>, Paul Gortmaker <paul.gortmaker-CWA4WttNNZF54TAoqtyWWQ@public.gmane.org>, Jan Kardell <jan.kardell@telliq.c>
List-Id: linux-input@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