These are example of controlling GPIO via hardware registers on
Snapdragon 410 system-on-chip (specific SoC model: APQ8016), as
used in various Android phones and with 96Boards project's
single-board computer Dragonboard410c.

Examples use MicroPython: https://github.com/micropython/micropython

Before running them, Linux kernel triggers should be shutdown:

for l in /sys/class/leds/*user*; do echo none >$l/trigger; done

Examples (just as the command above) should be run as root, as
required to access hardware in low-level way.