/sys/devices/platform/pixel_qi_screen_ctrl/state

event0 - hardware buttons
event1 - touch buttons
event2 - touchscreen

Ericsson F3307
AT+CFUN=1
AT+CGDCONT=1,"IP","$APN"
AT*ENAP=1,1
dhclient usb0

working:

xorg
touchscreen
wifi
usb host

to be checked:
wwan
gps

not working:
v4l2
sound

who needs this:
accelerometer
battery monitoring
cpu scaling
bluetooth