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Joysticks can be a bit of a hassle to get working in Linux. Not because they are poorly supported, but simply because you need to determine which modules to load to get your joystick working, and it's not always very obvious!

Determining which modules you need

For an extensive overview of all joystick related modules in Linux, you will need access to the Linux kernel sources -- specifically the Documentation section. Unfortunately, pacman kernel packages do not include what we need. If you have the kernel sources downloaded, have a look at Documentation/input/joystick.txt. You can browse the kernel source tree at by clicking the "C" (current changesets) link, then clicking the "tree" link near the top. Here's a link to the Documentation from kernel

Some joysticks need specific modules, such as the Microsoft Sidewinder controllers (sidewinder), or the Logitech digital controllers (adi). Many older joysticks will work with the simple analog module. If your joystick is plugging in to a gameport provided by your soundcard, you will need your soundcard drivers loaded - however, some cards, like the Soundblaster Live, have a specific gameport driver (emu10k1-gp). Older ISA soundcards may need the ns558 module, which is a standard gameport module.

As you can see, there are many different modules related to getting your joystick working in Linux, so I couldn't possibly cover everything here. Please have a look at the documentation mentioned above for details.

Loading the modules

You need to load a module for your gameport (ns558, emu10k1-gp, cs461x, etc...), a module for your joystick (analog, sidewinder, adi, etc...), and finally the kernel joystick device driver (joydev). Add these to your /etc/rc.conf, or simply modprobe them. The gameport module should load automatically, as this is a dependency of the other modules.

Testing Your Configuration

Once the modules are loaded, you should find a new device: /dev/input/js0. You can simply cat the device to see if it works - move the stick around, press all the buttons. I found my Logitech Thunderpad Digital had two buttons that weren't working with the analog module. After reading some docs, I saw there was a specific adi module for this controller. The moral of the story is, if it doesn't work the first time, do not give up, and read those docs thoroughly! I couldn't get anything working at all until I found that documentation.

Another way of testing is using jstest from the joyutils package. That package also has jscal for calibrating your device. If you have too many buttons and axes to fit on a single line or your pad has an accelerometer (it continuously sends new events even when nothing really happens) you should use a graphical tool. AUR has jstest-gtk-gitAUR for that purpose. It's essential for testing and troubleshooting a sixaxis.

USB joysticks

You need to get USB working, and then modprobe your joystick driver, which is usbhid, as well as joydev. If you use a usb mouse or keyboard, usbhid will be loaded already and you just have to load the joydev module.

PS3 controller

The Sixaxis gamepad works out of the box when plugged in via USB. Steam properly recognizes it as a PS3 pad and Big Picture can be launched with the PS button. Big Picture and some games may act as if it was a 360 controller.

Gamepad control over mouse is on by default. You may want to turn it off before playing games, See below.

Some people found that the controller is detected properly out of the box, but none of the buttons and analogs do a thing. Pressing the PS button solves he issue.

Xbox 360 controllers

The controllers should work without additional packages, but the wireless controller needs a wireless reciever (the charge-and-play cable can not be used for communicating with the controller). Both the wired controllers and the wireless reciever is supported by the xpad kernel module.

Unfortunately xpad has problems with new wireless controllers:

The working solution is use xboxdrvAUR. It is alternative driver wich works in userspace. It could be launched as system service.

If you wish to use the controller for controlling the mouse, or mapping buttons to keys, etc. you should use the xf86-input-joystick package (configuration help can be found using man joystick). If the mouse locks itself in a corner, it might help changing the MatchDevicePath in /etc/X11/xorg.conf.d/50-joystick.conf from /dev/input/event* to /dev/input/js*.

xboxdrv with two controllers

xboxdrv supports a multitude of controllers, but it works only in daemon mode. The simplest way is launch xboxdrv as service in daemon mode:

ExecStart = /usr/bin/xboxdrv -D -c /etc/conf.d/xboxdrv

And add support of the second controller in config file:

 silent = true
 next-controller = true
 dbus = disabled

Setting up deadzones

If you want to set up the deadzones of your analog input you have to do it separately for the xorg (for mouse and keyboard emulation) and the kernel driver (for gaming).

Deadzones in Xorg

Add a similar line into your /etc/X11/xorg.conf.d/50-joystick.conf before the EndSection:

Option "MapAxis1" "deadzone=1000"

1000 is the default value, but you can set anything between 0 and 30 000. To get the axis number see the "Testing Your Configuration" section of this article. If you already have an option with a specific axis just type in the deadzone=value at the end of the parameter separated by a space.

Deadzones in the Kernel Driver

The easiest way is using jstest-gtk-gitAUR. Select the controller you want to edit, then click the calibration button at the bottom of the dialog. You must set the CenterMin and CenterMax values for joysticks and analog sticks, RangeMin for triggers. Then use jscal for to dump the new values into a shell script:

jscal -p /dev/input/jsX > # replace X with your joystick's number 
chmod +x

Now you need to make a udev rule (for example /etc/udev/rules.d and name it 85-jscal.rules) so the script will automatically run when you connect the controller:

SUBSYSTEM=="input", ATTRS{idVendor}=="054c", ATTRS{idProduct}=="c268", ACTION=="add", RUN+="/usr/bin/"

To get the idVendor and idProduct use udevadm info --attribute-walk --name /dev/input/jsX

Finally we must announce SDL our joystick device, or else it will just ignore these to use its own settings. Add this to your ~/.bashrc : export SDL_JOYSTICK_DEVICE=/dev/input/jsX (Again, replace X to your device number.)

Disable Joystick From Controlling Mouse

If you want to play games with your controller, you might want to disable gamepad control over mouse cursor. To do this, edit /etc/X11/xorg.conf.d/50-joystick.conf so that it looks like this:

Section "InputClass"
        Identifier "joystick catchall"
        MatchIsJoystick "on"
        MatchDevicePath "/dev/input/event*"
        Driver "joystick"
        Option "StartKeysEnabled" "False"       #Disable mouse
        Option "StartMouseEnabled" "False"      #support


Joystick moving mouse

Sometimes USB joystick can be recognized as HID mouse (only in X, it is still being installed as /dev/input/js0 as well). Known issue is cursor being moved by the joystick, or escaping to en edge of a screen right after plugin. If your application can detect joystick by it self, you can remove xf86-input-joystick package.

More gentle solution is to add:

Option "StartKeysEnabled" "False"
Option "StartMouseEnabled" "False"

at the end of your /etc/X11/xorg.conf.d/50-joystick.conf of joystick InputClass.

Joystick sending keystrokes

This is a good solution for systems where restarting Xorg is a rare event because it's a static configuration loaded only on X startup. I use it on my media PC running XBMC controlled with Logitech Cordless RumblePad 2. Due to a problem with the d-pad (a.k.a. "hat") being recognized as another axis, I used to run Joy2key as a workaround. Since I upgraded to XBMC 11.0 and joy2key 1.6.3-1, this setup no longer worked for me. I ended up taking a more direct approach and let Xorg handle joystick events.

First, make sure you have xf86-input-joystick installed. Then, create /etc/X11/xorg.conf.d/51-joystick.conf like so:

 Section "InputClass"
  Identifier "Joystick hat mapping"
  Option "StartKeysEnabled" "True"
  #MatchIsJoystick "on"
  Option "MapAxis5" "keylow=113 keyhigh=114"
  Option "MapAxis6" "keylow=111 keyhigh=116"
Note: The MatchIsJoystick "on" line doesn't seem to be required for this to work but you may want to uncomment it.