answered
2017-11-22 09:01:22 +0200
@Universebenzene_Jolla: The "double tap from lpm" is supported. And it does not need any special hardware/firmware support i.e. it should work in all devices regardless of whether "real" double tap is supported or not. The problem with xperia is that there are issues with the "real" double tap -> double tap wakeups are disabled by default - and this disables also the "fake" ones.
So, if you want to have both the real double tap (with whatever issues it has) and fake ones from "lpm", this should suffice:
mcetool --unblank --block=2 --set-doubletap-wakeup=always # see note1
mcetool --set-low-power-mode=enabled
Or, If you just want to have "lpm" and "double tap from lpm" without activating the troublesome "real doubletap", the following should work. Needs root privileges (due to config file handling & service restart).
First make mce disable the double tap detection done by the touch panel fw
mcetool --unblank --block=2 --set-doubletap-wakeup=never # see note1
Then override the double tap control path so that mce no longer can enable it
systemctl stop mce
printf "[DoubleTap]\nControlPath=\n" > /etc/mce/99-mask-doubletap.ini # see note2
systemctl start mce
And finally, enable "lpm" and allow (fake) double tap wakeup processing
mcetool --set-low-power-mode=enabled
mcetool --set-doubletap-wakeup=proximity
Note1: Making changes to fw doubletap controls while display is off can cause issues in xperia - some details at https://together.jolla.com/question/166938/double-tap-on-sailfish-x/
Note2: This kind of custom setting files stay effective also over os upgrades -> To undo the effects, they need to be removed manually. If you are later unsure whether you have added such files or not, checking if there are files in /etc/mce that are not originating from any rpm packages might help, e.g.
rpm -qf /etc/mce/* | grep owned
file /etc/mce/99-mask-doubletap.ini is not owned by any package