I'm working on Beagle Bone Black, and I need to change the power button behaivor.
Img that I'm using: bone-debian-8.7-lxqt-4gb-armhf-2017-03-19-4gb.img
As the documentation says, this button can wakeup is the module has in suspend mode.
REF: BBONEBLK_SRM BeagleBone Black System Reference Manual Rev C.1
6.1.8.5 WAKEUP
The WAKEUP signal from the TPS65217C is connected to the EXT_WAKEUP signal on the processor.
This is used to wake up the processor when it is in a sleep mode.
When an event is detected by the TPS65217C, such as the power button being pressed, it generates this signal.