I've removed the "solved" mark. I have put the following script into the startup items. After reboot the touch is out of sync with the mouse pointer.
straight_left.sh
#! /usr/bin/env bash
xrandr -o normal
TOUCHPAD=`xinput list | grep "TouchPad" | grep -o -E -e 'id=[0-9]+' | cut -d = -f 2`
SCREEN=`xinput list | grep "ATML1000" | grep -o -E -e 'id=[0-9]+' | cut -d = -f 2`
xinput set-prop ${SCREEN} 'Coordinate Transformation Matrix' 1 0 0 0 1 0 0 0 1
xinput set-prop ${TOUCHPAD} 'Coordinate Transformation Matrix' 1 0 0 0 1 0 0 0 1
xrandr -o left
xinput set-prop ${SCREEN} 'Coordinate Transformation Matrix' 0 -1 1 1 0 0 0 0 1
xinput set-prop ${TOUCHPAD} 'Coordinate Transformation Matrix' 0 -1 1 1 0 0 0 0 1
How do I establish whether the straight_left.sh script has been run?