Game Input MultipleXer

I had a Driving Force GT wheel which is not supported and it doesn't work in PS4, so it was basically covering in dust... but the community is awesome and there exists a project called gimx that enables support for old wheels in new systems like PS4, so I decided to give it a try, and after a few hours understanding what I needed and getting my hands dirty, it is working perfect with the DIY adapter (using a Chinese atmega32u4 + CP2102 converter) and a Raspberry PI 2.

The official wiki is pretty well documented, so I'm going to explain the addons I've made to fit what I wanted

Autostart at boot in without X
Instead using a .desktop file that will start X and then gimx, I've created a simple systemd init file that starts gimx.

Simply create a file /etc/systemd/system/gimx.service with the following content:

Code: Select all

[Unit]
Description=GIMX  
After=syslog.target network.target

[Service]
User=pi  
Type=simple  
ExecStart=/usr/bin/gimx -p /dev/ttyUSB0 -c LogitechDrivingForceGT_G29.xml --nograb  
Restart=always  
RestartSec=5

[Install]
WantedBy=multi-user.target  

Run systemctl daemon-reload to notify systemd about the new file and systemctl enable gimx && systemctl start gimx to enable the gimx service start at boot and start it in the same line.

Please note LogitechDrivingForceGT_G29.xml file should be available in the pi home directory as /home/pi/LogitechDrivingForceGT_G29.xml

Notify when gimx is running
In order to have a proper confirmation about if the gimx service is up and running, I've created a simple python script that turns a led on if the gimx service is running.

The file is located at /home/pi/blink.py:

Code: Select all

#!/usr/bin/python
import os  
import time  
import RPi.GPIO as GPIO

led = 23  
button = 18  
GPIO.setmode(GPIO.BCM)  
GPIO.setup(led, GPIO.OUT)  
GPIO.setup(button, GPIO.IN, pull_up_down = GPIO.PUD_UP)

def Shutdown(channel):  
  GPIO.output(led, True)
  time.sleep(0.2)
  GPIO.output(led, False)
  time.sleep(0.2)
  GPIO.output(led, True)
  time.sleep(0.2)
  GPIO.output(led, False)
  os.system("sudo shutdown -h now")

GPIO.add_event_detect(18, GPIO.FALLING, callback = Shutdown, bouncetime = 2000)

while True:  
  found = False
  time.sleep(5)
  pids = [pid for pid in os.listdir('/proc') if pid.isdigit()]
  for pid in pids:
    try:
      cmd = open(os.path.join('/proc', pid, 'cmdline'), 'rb').read()
      if "gimx" in cmd:
        found = True
    except IOError: # proc has already terminated
      continue
  if found == True:
    GPIO.output(led, True)
  else:
    GPIO.output(led, False)

As a bonus, I've also added a button so when it is pressed, there is a little blink effect, and the pi is shutted down. Pretty cool uh?

The schema is the following:



To start at boot, simply add it to the pi user crontab (crontab -e) as @reboot /home/pi/blink.py

Order
All the wires, pi, etc. is hidden inside a Samsung Galaxy S6 box, which makes it pretty convenient.





Enjoy!