levd

Daemon with configurable properties that will control NZXT Kraken x61 liquid cooler.

Dependencies

This project depends on glog, yaml-cpp and libusb. On fedora:

$ sudo dnf install yaml-cpp-devel glog-devel libusb-devel

Building

To compile this project ensure you have an up-to-date cpp compiler toolchain that supports c++ 14. Also ensure you have the cmake build tool. To build:

$ mkdir build && cd build
$ cmake ..
$ make
$ sudo make install # Optionally

Installing

Using make install will install the program and its necessary config files into the filesystem. You'll need to run this command as sudo, as the installer will copy files into directories outside of your home directory. Here's what the output of make install should look like:

[100%] Built target kraken
Install the project...
-- Install configuration: ""
-- Installing: /usr/bin/kraken
-- Installing: /usr/bin/kraken-start.sh
-- Up-to-date: /etc/leviathan
-- Installing: /etc/leviathan/levd.cfg
-- Up-to-date: /etc/systemd/system
-- Installing: /etc/systemd/system/levd.service

Setting up for use as daemon

Now that all of the necessary files have been copied into their respecive locations (also with the correct permissions), you'll have to let systemctl be aware of the modifications we're introducing. Follow the examples below:

$ sudo systemctl daemon-reload # Use this whenever levd.service changes
$ sudo systemctl enable levd
$ sudo systemctl start levd # stop sends SIGKILL to process, gracefully terminating

Configuration

The program must see a valid levd.cfg file located in /etc/leviathan. A sample can be found in the config/ folder. Your configuration file must be in yaml format and contain at least the main_color, temperature_source, fan_profile and interval properties.

To set a fan curve, add to the fan_profile list, other lists of size two. These are data points which build your fan profile curve - x value being temp (cpu or liquid, in C) and y value being fan percentage (in factors of 5, 30 being lowest, 100 highest).

You can also set a different profile for the pump using pump_profile. If unspecified, the pump will follow fan_profile. For example:

fan_profile:
  -
    - 30
    - 30
  -
    - 35
    - 40
  -
    - 40
    - 60
  -
    - 42
    - 70
  -
    - 43
    - 80
  -
    - 45
    - 100

At a temperature of 30C the fan/pump will operate at their lowest value, 30%. At a reading of 37C the program will perform the necessary calculations to find the fan/pump value 48% - then rounding up to the nearest multiple of 5, being 50%. All of this happens every interval, which by default is 0.5 seconds.

Real-time updates to the levd.cfg file are supported. No need to relaunch the daemon every time you modify a property.

Logging

Using journalctl you can see the programs stderr/stdout logs.

$ sudo journalctl -f -u levd.service
[sudo] password for [user]:
-- Logs begin at Wed 2017-08-16 15:57:01 EDT. --
Aug 16 20:18:13 localhost.localdomain systemd[1]: Started Leviathan - Daemon for Kraken x61 Watercooler.
Aug 16 20:31:02 localhost.localdomain kraken-start.sh[22349]: I0816 20:31:02.675717 22349 main.cpp:20] There are 15 usb devices hooked up
Aug 16 20:31:02 localhost.localdomain kraken-start.sh[22349]: I0816 20:31:02.675858 22349 main.cpp:24] Kraken X61 is detected
Aug 16 20:31:02 localhost.localdomain kraken-start.sh[22349]: I0816 20:31:02.675865 22349 main.cpp:25] Starting levd service...
Aug 16 20:31:02 localhost.localdomain kraken-start.sh[22349]: I0816 20:31:02.676039 22349 leviathan_service.cpp:68] Kraken Driver Initialized
Aug 16 20:31:02 localhost.localdomain kraken-start.sh[22349]: I0816 20:31:02.676582 22349 leviathan_service.cpp:69] Kraken Serial No: CCVI_1.0
Aug 16 20:31:02 localhost.localdomain kraken-start.sh[22349]: I0816 20:31:02.677431 22349 leviathan_service.cpp:100] Detected modifications to config file, updating
 preferences...
Aug 16 20:31:02 localhost.localdomain kraken-start.sh[22349]: I0816 20:31:02.925264 22349 leviathan_service.cpp:118] Changed fan speed to: 1020
...

...
Aug 16 20:36:56 localhost.localdomain systemd[1]: Stopping Leviathan - Daemon for Kraken x61 Watercooler...
Aug 16 20:36:57 localhost.localdomain kraken-start.sh[22349]: I0816 20:36:57.116379 22349 main.cpp:31] ... driver gracefully shutting down
Aug 16 20:36:57 localhost.localdomain systemd[1]: Stopped Leviathan - Daemon for Kraken x61 Watercooler.

And running systemctl status levd can give you quick insight into the status of the daemon

$ sudo systemctl status levd.service
● levd.service - Leviathan - Daemon for Kraken x61 Watercooler
   Loaded: loaded (/etc/systemd/system/levd.service; enabled; vendor preset: disabled)
   Active: active (running) since Wed 2017-08-16 20:37:19 EDT; 46s ago
 Main PID: 22870 (kraken)
    Tasks: 2 (limit: 4915)
   CGroup: /system.slice/levd.service

Acknowledgements

https://github.com/jaksi/leviathan

As I was reverse engineering the windows driver, I later found out that someone else did a way better job then me :)

This project would not have been possible without contributions to the open source community from jaksi.