This is a kernel module for Ralink RT3290 chip which makes it work with Bluez software and driver. Works like a charm on HP 250 g3 laptop.

This module has no official support by Mediatek. Support was discontinued.

Usage:

# Init
sudo modprobe rtbth
sudo rfkill unblock bluetooth
hcitool dev # check

# Switch off
sudo rfkill block bluetooth

# Switch on
sudo rfkill unblock bluetooth

# Shutdown
sudo pkill -2 rtbt
sudo rmmod rtbth

Blob issues:

No support for Bluetooth Protocol v4.0 and more recent. Configure your devices to use legacy mode.