Fix Driver Issues with CH340G on Ubuntu 22.04 LTS ( and possibly other Linux Distro's)

Having recently upgraded to Ubuntu 22.04 LTS ( After the local power-company managed to destroy my HP ML350-G6 server, with a UPS installed, with a power surge or something - still no answers -- :( ) on a new more modern Desktop computer, I found some intermittent issues with my ESP32 / ESP8266 and Arduino boards... The Serial port would not work at all ( on devices with CH340G chips )...

A quick online search found the following, link to the original article here,

Instructions for Ubuntu 22.04 LTS x86_64

01Get the currently installed kernel version:

sudo apt-get update -y
sudo apt-get install neofetch -y
neofetch

I think it came with Kernel: 5.13.8-...

02Install latest kernel (GUI solution):

sudo add-apt-repository ppa:cappelikan/ppa
sudo apt-get update -y
sudo apt-get install mainline -y
sudo apt autoremove -y

Run mainline and select the latest kernel (I tried, as of 16/05/2022, kernel version: 5.17.8-051708-generic)

After installation and reboot, run neofetch again and check if the latest linux kernel is loaded.

03Install build tools (if not installed already):

sudo apt-get update -y
sudo apt-get install build-essential dwarves dkms make cmake -y
sudo apt autoremove -y

04Install and fix CH34x drivers:

As per the guide here in sparkfun and https://github.com/juliagoda/CH341SER

git clone https://github.com/juliagoda/CH341SER
cd CH341SER
sudo make clean 

# The Makefile looks for vmlinux in a certain location (check that cat Makefile)
# we need to move that
# https://forum.proxmox.com/threads/kernel-module-not-found-when-compile-skipping-btf-generation.100974/
cp /sys/kernel/btf/vmlinux /usr/lib/modules/`uname -r`/build/

sudo make
sudo make load
lsmod | grep ch34*

# NOTE: if other/prev ch34x drivers are loaded (and you know they were not working), then you can unload them by:
sudo rmmod ch34x

# Plug and unplug your CH340 device again on the USB port
sudo dmesg

# plug un-plug your device and then verify:
ls /dev/tty*

# make it accessible
sudo usermod -a -G dialout $(whoami)
sudo chmod a+rw /dev/ttyUSB0 # if /dev/ttyUSB0 was assigned

# To unload:
sudo rmmod ch34x
# or 
sudo make unload

05Disable some conflicting services.

It came out during my test, at least on my machine, a service for some external brail hardware was conflicting with the drivers. I saw that in sudo dmesg

... ch340 1-10:1.0: ch341-uart converter detected
... usb 1-10: ch341-uart converter now attached to ttyUSB0
.
.
.
... usb 1-10: usbfs: interface 0 claimed by ch341 while 'brltty' sets config #1
... ch340-uart ttyUSB0: ch341-uart converter now disconnected from ttyUSB0

It was apearing and dis-appearing. so I tried to hunt the service as such:

sudo systemctl list-units | grep brltty

I then disabled it:

sudo systemctl stop <brl service name or other service that is interfering and not needed>
sudo systemctl disable <brl service name or other service that is interfering and not needed>
sudo systemctl mask <brl service name or other service that is interfering and not needed>

for f in /usr/lib/udev/rules.d/*brltty*.rules; do
    sudo ln -s /dev/null "/etc/udev/rules.d/$(basename "$f")"
done
sudo udevadm control --reload-rules