From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Cochran <richardcochran-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH 1/4] input: touchscreen: ti_am335x_tsc Interchange
 touchscreen and ADC steps
Date: Fri, 7 Nov 2014 11:17:14 +0100
Message-ID: <20141107101714.GA23102@netboy>
References: <1414408111-2631-1-git-send-email-vigneshr@ti.com>
 <1414408111-2631-2-git-send-email-vigneshr@ti.com>
 <20141106141916.GA17151@netboy>
 <545C59CD.3070707@ti.com>
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To: Vignesh R <vigneshr-l0cyMroinI0@public.gmane.org>
Cc: 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>, Dmitry Torokhov <dmitry.torokhov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Lars-Peter Clausen <lars-Qo5EllUWu/uELgA04lAiVw@public.gmane.org>, Samuel Ortiz <sameo-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>, Jan Kardell <jan.kardell-KSZdJiTw9mzQT0dZR+AlfA@public.gmane.org>, linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Sebastian Andrzej Siewior <bigeasy-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org>, linux-input-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Felipe Balbi <balbi-l0cyMroinI0@public.gmane.org>, Paul Gortmaker <paul.gortmaker-CWA4WttNNZF54TAoqtyWWQ@public.gmane.org>, Peter Meerwald <pmeerw-jW+XmwGofnusTnJN9+BGXg@public.gmane.org>, Hartmut Knaack <knaack.h-Mmb7MZpHnFY@public.gmane.org>, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Lee Jones <lee.jones-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>, linux-arm
List-Id: linux-input@vger.kernel.org

On Fri, Nov 07, 2014 at 11:04:05AM +0530, Vignesh R wrote:
> Currently, there is too much noise in the TSC hardware that is being
> removed by delta filtering. I tested TSC unit by removing filtering
> logic, the performance was not at all satisfactory. The cursor jumps
> wayward and smooth circles cannot be drawn. Looks like delta filtering
> cannot be removed as of now. May be I will try and address it in future.

FWIW, on the boards that I tested, I printed the measured values out,
and I found that with 5 repetitions, I got the same value 5 times,
plus or minus a very small delta.

Thanks,
Richard