2023-06-15 This project will not be maintained because the unit I had was buggy (garbled OLED) and the replacement unit is buggy too so am going to buy a different brand. I do hope this project to be useful for anyone else so leaving the code up.

Komplementary Kontrol

Unofficial Linux support for the Komplete Kontrol A-series keyboard by Native Instruments

I am in no way affiliated with Native Instruments

DISCLAIMER : USE THIS AT YOUR OWN RISK

I cannot be held responsible for any problems that might arise from using these utilities.

Now that that is out of the way...

About

This is a set of utilities to make the Komplete Kontrol A-series keyboards usable under Linux.

This has been developed using a A25 but I don't see any reason why this could not work for the other A-series keyboards.

It consists of two utilities:

• komplement
• konfigure

The komplement tool is the thing that makes the non-MIDI buttons usable on your system. See below.

The konfigure tool generates SysEx packets that can be sent to the device to configure the current preset (i.e. that maps the rotary dials to actual MIDI events). See below.

Compiling and installing

The konfigure requires libasound2-dev, the komplement tool additionally requires libhidapi-libusb0.

To install required libraries, run apt install libhidapi-libusb0 libasound2-dev

To compile the binaries, run make all

If you want to install it on your system, run sudo make install

Note: Installation will also create the folders /usr/share/komplementary-control/mappings and /usr/share/komplementary-control/presets where the mappings and presets are copied to. This is where the utilities will try to find the files if they do not exist in the path, so running komplement -m rosegarden.map will load it from /usr/share/komplementary-kontrol/mappings/rosegarden.map.

komplement

This basically works by reading the relevant USB HID packets and mapping that to keys useful for your favourite software.

This means that if your software is not the active window, any other active application will receive the keypresses. This is something to keep in mind.

Due to how it works, it needs to run while you want to use the keyboard in your DAW.

If you are done using it, you can simply hit Ctrl+C to abort it and it shall gracefully exit.

Permissions

This utility required read/write access to the USB device and only write to /dev/uinput for sending keypresses.

Note that it doesn't read from uinput, so your passwords are safe.

Access to these can be accomplished by either running the komplement binary as root, or allowing user access to the necessary files.

Obviously, the latter is encouraged. (Running as root is bad, mkay.)

The setfacl utility can be used to allow write access to the /dev/uinput file.

    $> sudo setfacl -m u:$USER:w /dev/uinput

Note that changes with setfacl are not permanent and will need to be applied again after a reboot.

For convenience, I have created the file udev/55-komplete-kontrol.rules that can be used to set up USB device access for the group audio (chances are you have already added yourself to that group). If not, edit the rules file to a group you do belong to.

After copying that file (as root) to /etc/udev/rules.d and then running sudo udevadm control --reload-rules

You can unplug / plug the device so that permissions are set-up properly and then you no longer need to run the utility as root.

Mapping files

An example mapping is supplied in mappings/rosegarden.map that maps useful buttons to functionality in Rosegarden. This file can serve as a basis to create mappings for other software.

Check the file doc/Supported_Keys.md for a list of all the supported keys.

(If you do create your own, please share your mapping files so others can use it too!)

Examples

Example usage that loads the Rosegarden mapping and /dev/uinput for output:

$> ./komplement -m mappings/rosegarden.map -o /dev/uinput

(The above example assumes that the permissions are correctly set up.)

konfigure

This is a utility that creates a SysEx file that can be sent to the device to configure it the rotary knobs.

Preset files

An example preset file is supplied in presets/basic_cc.pst that maps a few CC to the buttons.

Examples

Example that writes it to a separate file that you can then send to the appropriate device with the amidi utility:

$> ./konfigure -i presets/basic_cc.pst > /tmp/sysex.syx
$> amidi -s /tmp/sysex.syx

It is also possible to send it directly to the device like so:

$> ./konfigure -i presets/basic_cc.pst -p "hw:3,0,0"