Summary: After a successful ts_calibration and ts_test, ts_test shows 
varying results after reboots.

I am connecting a beaglebone black to a 16 bpp, 4 wire touchscreen/LCD. The 
lcd is working beautifully, but I am having an issue with the touchscreen. 
I am connecting AIN0-3 directly to the up, down, left, and right pins of 
the touchscreen via breadboard and breakoutboard.

I can boot up a 3.8 RCN kernel with a custom device tree overlay (and also 
a modified 3.2 kernel), I can run ts_calibrate and ts_test and get perfect 
results.

The problem occurs on reboots, sometimes the results of ts_test are near 
perfect, sometimes they are off by a small but significant amount, 
sometimes it is way off. On a reboot when ts_test is off, if I run 
ts_calibrate then the results of ts_test are right on the mark.

I haven't been able to make heads or tails of this, whether to focus an 
hardware or software.

Looking at the touch signals with a scope there is a small amount of noise 
that seems to increase in frequency as more is displayed on the LCD. 
However the calibration never seems to change once the board is booted so I 
do not believe that the noise is at the root of my issue.

/etc/ts.conf contains

module_raw input
module pthres pmin=1
module variance delta=30
module dejitter delta=100
module linear

I'm exporting the following before running any ts_* utils:

export TSLIB_CONSOLEDEVICE=none
export TSLIB_CONFFILE=/etc/ts.conf
export TSLIB_CALIBFILE=/etc/pointercal
export TSLIB_TSDEVICE=/dev/input/event1
export TSLIB_FBDEVICE=/dev/fb0
#export TSLIB_PLUGINDIR=/usr/lib/ts
export TSLIB_PLUGINDIR=/usr/lib/arm-linux-gnueabihf/ts0
export TSLIB_TSEVENTTYPE=INPUT


I have a debian rootfs and I've installed tslibs via apt-get, but I've also 
cross compiled tslibs-1.0 and tslibs-1.1 from:

https://github.com/kergoth/tslib

With the same results.

Any ideas/suggestions would be greatly appreciated.

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