A user sent me a PM to explain him how to install Touchscreen drivers. Putting it here for everyone's reference.
BTW, it does not work in Fedora and only works on Ubuntu/Ubuntu based distros and Arch.
1. After installing Ubuntu, make sure that you have updated all the software.
2. Download touchscreen drivers from this location. https://github.com/onitake/gsl-firmw...e/linux/silead
3. Rename the driver to mssl1680.fw
4. Copy the driver into /lib/firmware/silead. The folder silead does not exist, you need to create one.
5. Uninstall driver xserver-xorg-input-libinput and install driver xserver-xorg-input-evdev
6. Install xinput-calibrator and run the program
7. Calibrate your screen and touchscreen starts working as expected.
8. Copy the settings in the terminal to /usr/share/X11/xorg.conf.d/99-calibration.conf
It works permanently now.
---------- Post added at 11:09 AM ---------- Previous post was at 11:02 AM ----------
BTW, my Chuwi has died. I have been travelling a lot lately and I have been using my Phone charger to charge up Chuwi. My Phone has QC 3.0 charger and can deliver 12 V at 1.5A or 5V 3A. It worked fine for a couple of days because 5V 3A is the rating of our Chuwi charger. But then the charging circuit went kaput one day and now, whenever I turn it on even without connecting the charger, it overheats around the USB-C port and it trips off within few seconds. It's not because of heat sink because the heatsink is still in place and I inspected damage. It's directly below the micro USB port. Broke the tab into thousand pieces and threw it away.
Bottom line - Chuwi charger is only 5V 2A one and do not charge it with a bigger charger. Once or twice is fine but if you charge like that for a month or so, it will fail as mine did.
Side note - I repurposed the Keyboard device to work as a USB device. It is a very simple mod and if anyone is interested, I can post a tutorial here.