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Linux Mint 20.2 on a ThinkPad E14 (Ryzen 7, gen 2)

23 July, 2021

I’ve recently got a new laptop, a Lenovo ThinkPad E14 with a Ryzen 7 Pro (and hence integrated Radeon Renoir graphics) and 16GB RAM. It came with Windows 10 Pro but after allowing myself a few days to play some older Windows games I’ve installed my favourite Linux distro, Mint 20.2 Cinnamon.

I’ve had ThinkPads before. I’ve got an old T420 and I’ve recently retired an old X1 Carbon, a Yoga S730, and a second-hand ThinkBook 13. Having run Linux on all of them I wasn’t expecting issues.

It turns out Linux on the ‘E’ range of ThinkPads is not specifically supported by Lenovo.

Mint installs without issue. The usual suspects all worked, liked WiFi and audio. However there were two issues, an initial one and a second which became obvious by the fix to the first.

  • The function keys do not work properly and keyboard LEDs do not light up
  • Waking from Suspend leaves me at a blank screen (working, but no display)

So here are details of how I got past these issues; it only takes a few minutes to do. There’s also an issue with scaling in Firefox (that is not specific to this machine) which I’ll cover in passing.

Function keys

The issue

The keyboard backlight and the function lock both work fine (though the indicator on the latter doesn’t change). All alternative uses of the function keys fail to operate, like the volume, brightness, and mute keys.

The fix

The solution is to suspend immediately after booting up. After resuming, the keys work fine. Here’s how you can do it manually if you want to just add a script to your desktop which you run after login:

systemctl suspend

It’s a little hacky, though, so you can make it happen automatically during boot-up. All you need to do is update your cron jobs. If that means nothing to you don’t worry, just give it a go anyway.

sudo crontab -e

Add the following line at the end of the file that opens, then save and reboot after you do the next fix.

@reboot sudo rtcwake -m mem -s 2

There is still that second issue of suspend/resume dropping into a blank screen. To get around this you need the next fix.

Suspend resumes with a blank screen

As mentioned, waking from Suspend results in a working system but with no display. The Linux kernel in use (as of Mint 20.2 Cinnamon) is 5.4. Upgrading to 5.8 will fix the Resume functionality.

  • Download the following into your home folder
  • Navigate into your home folder and install the new kernel via the terminal
sudo dpkg -i *.deb
  • Then reboot and check using uname -r

Note that Update Manager may remove the 5.8 headers when it next runs. This doesn’t appear to break things again, and it will probably re-install them the very next time it runs anyway.

Issue with high-DPI screens in Firefox

This is not specific to this machine - not even to Mint as it happens.

Browsing in Firefox you’ll see tiny pages. You can change default fonts and zooms in Firefox, but that’s a hack. Here’s how you can fix things in the Firefox settings.

  • Open Firefox and browse to about:config
  • Search for the option layout.css.devPixelsPerPx
  • Change the value to 1.2, press enter, and close the config

Hope those help - with all that in place it’s an excellent Linux machine.