Install
Arch Linux
with
KDE Plasma
on a
Lenovo X220 Tablet

go to mb.sb

This is a guide to install Arch Linux with KDE Plasma on a Lenovo X220 Tablet laptop.

Here's a video of the laptop in tablet mode, running GIMP: link

Using the stylus in GIMP, with pressure sensitivity. Here's a higher-resolution version of the video.

• Rotating the screen with a tablet button
• Drawing with the stylus in GIMP, making use of the stylus' pressure sensitivity
• Using a different brush when drawing with a finger
• Erasing with the back side of the stylus
• Right clicking with a tablet button
• Entering text with a virtual keyboard, inserting a custom text snippet

Especially the first half of this guide contains instructions that can also be found in the excellent ArchWiki entry. A few steps in this guide here are simpler than in the ArchWiki since they only have to work on this specific laptop, not on any other machine.

In the second half, we'll go beyond what's covered in the ArchWiki and configure the laptop's tablet mode.

Write Installation Image to USB Drive

For this step, you'll either use the operating system currently running on your Lenovo X220 Tablet or a different computer.

Download the Arch Linux ISO file from here, preferably via BitTorrent.

After plugging in a USB drive, make sure it's not mounted. If you're already running Linux, you can unmount with umount /run/media/$USER/*. Then, with lsblk -fs find out the name of your USB drive device, it starts with "sd". Historically, this stood for "SCSI disk" but also refers to USB drives nowadays. Assuming your drive is "sdb", write the ISO image to the USB drive using dd:

dd bs=4M if=path/to/archlinux.iso of=/dev/sdb status=progress oflag=sync

Boot the Live USB Drive

Connect to the Internet

If you had an Ethernet cable plugged in while booting, you should already be connected to the internet. Make sure by running ping archlinux.org. If you've plugged in an Ethernet cable after booting, you can configure network access (including getting an IP address) by running dhcpcd.

wpa_passphrase myRouter verySecretPassword | wpa_supplicant -B -i wlan0 -c /dev/stdin; dhcpcd wlan0

Set the Time

timedatectl set-ntp true

Partition the Disk, Format the Partition

If you want to back up preexisting data on the Lenovo's disk, now's the last chance. After completing this section, data on your disk will be much harder to extract or lost entirely.

1. Create a new DOS partition table with o.
2. Create a new partition with n, select p to make the partition a primary one.
3. Select partition number 1, that's the default.
4. Select 2048 as the partition's first sector (also the default). A sector in our case is 512 bytes.
5. In the next step, fdisk uses the last sector of the disk as the partition's last sector per default. You can keep that default or have a smaller partition by entering "+80G", for example, to create a partition with 80 GiB.
6. Finally, write the changes to disk with w.

This creates a partition at /dev/sda1, which you can verify with fdisk -l.

In the first step in fdisk you selected to create a DOS partition table. This means fdisk wrote the Master Boot Record (MBR) to the first 512 bytes of the disk. The MBR contains the location of the partitions on the disk (we only have one partition). As we'll see in the section on GRUB, the MBR will also contain a little bit of code that loads parts of the GRUB bootloader, whose task it is to boot our operating system.

mkfs.ext4 /dev/sda1

To convince yourself that the partition now has an ext4 file system, call lsblk -fs and check the value of FSTYPE for /dev/sda1.

mount /dev/sda1 /mnt

mkdir /mnt/etc; genfstab -U /mnt >> /mnt/etc/fstab

Install Packages

Open the file /etc/pacman.d/mirrorlist with vim or nano and put a server's URL which is close to you at the top. The first server per default is in Melbourne, Australia which, depending on where you are in the world, might incur significant lag when downloading packages.

Server = https://packages.oth-regensburg.de/archlinux/$repo/os/$arch

pacstrap /mnt base base-devel linux linux-firmware grub plasma vi sddm sudo networkmanager man packagekit-qt5 konsole

• linux-firmware contains closed source drivers. In case you're curious what happens if we don't install linux-firmware: The Wi-Fi interface such as wlp3s0 won't show up and you won't find an access point (your router) to connect to wirelessly.
• base-devel provides developer tools like make for building software, for example with Aura. It also has sudoedit which is helpful when you need to edit files owned by root.
• PackageKit is a program that Discover uses to interact with pacman, Arch Linux' package manager.
• SDDM will provide a graphical login screen when starting your system.

Set up Your System

• In the file /etc/pacman.d/mirrorlist put a server URL at the top whose location is close to you. Just like before on the live USB drive.
• Define your time zone, for example: ln -sf /usr/share/zoneinfo/Europe/Vienna /etc/localtime
• Synchronize the software clock with the hardware clock: hwclock --systohc
• Set a password for root: passwd
• Create a regular user: useradd regularUser --create-home --groups wheel
• Set a password for the regular user: passwd regularUser.
• Call visudo and uncomment this line: %wheel ALL=(ALL) ALL. This allows members of group "wheel" to execute any command. To be able to run visudo, we need vi which is the reason why we've installed it using pacstrap.
• Make a couple of services start at boot: systemctl enable NetworkManager sddm

Install GRUB as the Bootloader

grub-install --target=i386-pc /dev/sda && grub-mkconfig -o /boot/grub/grub.cfg

Don't let the i386 part throw you off: Your operating system is 64-bit.

Overview of How Arch Linux Boots with GRUB

This section provides a cursory explanation of how the boot process works with GRUB on the X220 Tablet. If you're only interested in getting Arch Linux running and have already installed the bootloader in the previous step, you can safely skip this section and continue here.

1. boot.img: This is code written to the master boot record (MBR). The MBR is a region taking up the first 512 bytes of our disk /dev/sda. The job of boot.img is to load core.img.
2. core.img: more code that comes after the MBR but before our partition /dev/sda1 which starts at sector 2048. We've set the partition's start sector when creating it with fdisk. The job of core.img is to load the normal module at /boot/grub/i386-pc/normal.mod. Since core.img needs to work with file paths, it contains code to access file systems.
3. the directory at /boot/grub/ which lives on our partition /dev/sda1. This directory contains the normal module. This module executes /boot/grub/grub.cfg which we created with grub-mkconfig.

The file /boot/grub/grub.cfg is a shell script that displays the available operating systems in a textual menu after powering up. Once you've selected an operating system, grub.cfg boots it. In our case, we only have one operating system, Arch Linux, whose kernel is a file at /boot/vmlinuz-linux.

To get a better understanding of the boot process, this graphic shows the physical components of your laptop where those programs exist (not to scale):

You can see that grub-install writes core.img into the gap between the MBR and the beginning of the partition /dev/sda1. This area is neither part of a partition nor formatted with a file system. Instead, grub-install writes core.img's location on the disk to the MBR.

Where exactly on the disk is core.img? I used this answer to find out on my disk it starts at byte 512, which is sector 1.

You can learn more about GRUB in its manual. For a look inside the MBR, check out this page.

The BIOS chip on the Lenovo X220 Tablet is the EEPROM labelled L08, soldered to the top left of the system board, next to the fan. Here are images of the X220's system board with the BIOS chip pointed out.

Reboot and Install Applications

After GRUB is installed, you can exit chroot with exit or pressing Ctrl+d. Unmount the partition with umount /mnt then reboot.

When the system has booted, SDDM should present you with a login screen. Log in with the password of your regular user. Once logged in, you can pick an image for your user in System Settings → User Manager. To allow SDDM to show this image on the login screen, do

setfacl -m u:sddm:x ~/; setfacl -m u:sddm:r ~/.face.icon

This command uses access control lists to allow the user sddm to enter your home directory and then grants that user read rights to the file .face.icon.

You can install preferred applications via Discover or use a terminal emulator like Konsole to call pacman directly. Press Alt+Space to summon KRunner that lets you launch those programs by typing their names.

sudo pacman -Sy firefox thunderbird gwenview dolphin vlc okular libreoffice-still ark gimp spectacle ntfs-3g

• plasma-thunderbolt is unnecessary since this laptop doesn't have a Thunderbolt or USB-C port.
• I don't use Vault for storing secrets.

sudo pacman -Rs plasma-thunderbolt plasma-vault

Installing Aura

Localization

• Edit /etc/locale.gen, uncommenting de_AT.UTF-8 UTF-8, then generate the locale using sudo locale-gen.
• Set the system language (you'll have to scroll down a bit if your language starts with a non-ASCII character): System Settings → Regional Settings → Formats
• Localize LibreOffice: sudo pacman -S libreoffice-still-de. Use pacman -Ss libreoffice-still-* to find the package for your language.
• Localize Thunderbird: sudo pacman -S thunderbird-i18n-de. Use pacman -Ss thunderbird-i18n-* to find the package for your language.
• Localize Firefox: Choose "Search for more languages..." in Firefox' preferences.

Tablet Mode

Rotate the Screen

• The leftmost button with the dot in the middle is the laptop's second power button. It's slightly larger than the other two buttons.
• The center button with the arrow forming a clockwise circle is called the "Secure Attention Sequence" button on page 46 of the laptop's manual, it triggers the Ctrl+Alt+Del key combination on Windows. When pressed on Linux, this button creates an XF86TaskPane key event. You can confirm this by running xev and pressing the button.
• The button to the right is the one we'll use to rotate the screen. From xev we know that it creates the XF86RotateWindows key event.

The Script

#!/usr/bin/sh

# Get your display name with xrandr
display="LVDS-1"

# Names of screen inputs, from xinput
touch_input="Wacom ISDv4 E6 Finger"
stylus_input_tip="Wacom ISDv4 E6 Pen Pen (0)"
# The red button on the back of the stylus
stylus_input_eraser="Wacom ISDv4 E6 Pen Eraser (0)"

ctm="Coordinate Transformation Matrix"

# Turns coordinates on their heads
inversion_matrix="-1 0 1 0 -1 1 0 0 1"

# Leaves coordinates as they are
identity_matrix="1 0 0 0 1 0 0 0 1"

# The current screen rotation: One of "normal", "inverted", "left", "right"
cur_rotation=$(xrandr -q --verbose | grep "$display" | cut -d" " -f6)

echo "Let's rotate the screen"
echo "Current rotation is $cur_rotation"

if [ "$cur_rotation" = "normal" ]; then
    echo "Invert the screen and the inputs for touch and stylus"
    xinput set-prop "$stylus_input_tip" "$ctm" $inversion_matrix
    xinput set-prop "$stylus_input_eraser" "$ctm" $inversion_matrix
    xinput set-prop "$touch_input" "$ctm" $inversion_matrix

    xrandr -o inverted
else
    echo "Return the screen and the inputs to normal"
    xinput set-prop "$stylus_input_tip" "$ctm" $identity_matrix
    xinput set-prop "$stylus_input_eraser" "$ctm" $identity_matrix
    xinput set-prop "$touch_input" "$ctm" $identity_matrix

    xrandr -o normal
fi

The command xrandr -o inverted turns your screen output upside down. You might think that you're done after that, but as soon as you touch the screen, you'll notice that the cursor is off: If you touch the lower left of the screen, the cursor ends up in the upper right and vice versa. The reason for this is that while the screen output has been inverted, the screen input has not.

xinput set-prop "Wacom ISDv4 E6 Finger" "Coordinate Transformation Matrix" -1 0 1 0 -1 1 0 0 1

I've created a directory at ~/.local/scripts, put the script in there, and made it executable with

chmod +x ~/.local/scripts/flip_screen.sh

I recommend running the script directly via Bash to see if it works. When you call the script again, it will return the screen input and output to normal. If you intend to use that script on a different machine, you'll want to adapt the names of the screen inputs and outputs (the displays). Get them with xinput and xrandr, respectively.

The Shortcut

In Plasma's system settings, we add a shortcut to call this script when the screen rotation tablet button is pressed:

Select the Trigger tab. After clicking the button saying "None", press the rightmost tablet button:

~/.local/scripts/flip_screen.sh

Right Click in Tablet Mode

While we're at it, let's define a second shortcut for making life easier in tablet mode: Simulate a right click with the mouse. This is convenient when using GIMP in tablet mode. You can use the stylus for drawing (see this section) and show the right click context menu by pressing the remaining tablet button:

sudo pacman -Sy xdotool

• Create another Global Shortcut in Custom Shortcuts with a Command/URL target, just like for the screen-flipping script.
• In the Trigger tab, press the GUI button saying "None" and then the physical button. The GUI button should say "Task Panel" now.
• In the Action tab, add xdotool click 3.

Virtual Keyboard

sudo pacman -Sy qt5-virtualkeyboard

sudoedit /etc/sddm.conf.d/virtualkbd.conf

[General]
InputMethod=qtvirtualkeyboard

When you log out, SDDM will show a button with a keyboard icon saying "Virtual Keyboard" on the lower left of the login screen. Pressing that button activates an on-screen keyboard for you to type your password.

Onboard

sudo pacman -Sy onboard

To have Onboard started each time you log in, call Autostart with KRunner (Alt+Space) and select Onboard from the "Utilities" category.

Use the Stylus in GIMP

• Wacom ISDv4 E6 Pen Eraser (0)
• Wacom ISDv4 E6 Pen Pen (0)

I could still use the stylus to draw, but the stylus would show up as the Core Pointer in the Device Status dialog. This way, I wasn't able to make the brush grow and shrink with the pressure I applied with the stylus to the screen.

It seems that GIMP recognizes the devices if you just draw with the stylus and also with its red backside, the eraser, and then restart GIMP. Afterwards, the stylus' two devices were not grayed out anymore in the menu at Edit → Input Devices. Make sure those devices are not grayed out, then set their mode from Disabled to Screen. This allows making use of the stylus' pressure sensitivity in GIMP.

Assign Input Devices to GIMP Tools

1. the tip of the stylus draws using GIMP's paintbrush
2. the red eraser at the back of the stylus is GIMP's eraser, naturally
3. the regular Core Pointer, controlled with a mouse or a finger, performs a bucket fill

To change the GIMP tool associated with the input device, let's say for the stylus, make sure the stylus is the current input device by hovering over the image window in the center. Then, select a different tool from the toolbox or modify the tool using the Tool Options, the dialog with this icon:

By changing the pressure you apply with the stylus, you can vary various properties of the brush. I wanted to change the size of the brush: Applying little pressure with the stylus draws a fine line (small brush) and applying more pressure makes the line thicker (big brush). In GIMP, you can define this behavior with paint dynamics in the Tool Options.

Where to Go from Here

If things went smoothly, your X220 Tablet should be ready for action now, with applications installed on top of a desktop environment, tablet mode configured, using the language of your choice.

Troubleshooting

No Touchpad and Pointing Stick after Suspend

Sometimes, after the laptop wakes up from sleep, the touchpad and the red pointing stick on the keyboard don't work, meaning you can't move your mouse. Moving the cursor by touching the screen still works, though.

sudo rmmod psmouse; sudo modprobe psmouse proto=bare