../couch-gaming
Couch gaming with WoL, Steamlink, gamepad and LG TV API
I recently purchased a mini PC to use as a media center and home server. One of the things I wanted to explore was streaming games from my desktop PC to the TV. This works well enough, but it is kind of a hassle to get to the gaming:
- If off, turn on the TV
- Select correct HDMI-input (no CEC on the mini PC)
- Launch SteamLink, which means I have to fish out the keyboard/trackpad-combo from under the table (Logitech K400)
- If it is not running, I also have to power on / wake the Desktop PC.
Hardly a console-like experience!
So instead of using my limited time to enjoy some gaming, I ended up scripting the whole thing. I wanted to be able to just pick up the gamepad and jump into a game. Using Python and Alga, I was able to achieve this quite nicely.
The script waits for a connected gamepad, and if present, listens for a specific button combo held for a few seconds. This triggers a set of steps that:
- Rumbles the controller to indicate that the script is started
- Turns on the TV, using Wake On Lan
- Turns on the desktop PC, also using Wake On Lan
- Sets the TV to the correct HDMI-input, using Alga
- Jiggles the mouse cursor, in cases where the TV is on and set to the right input, but the screensaver / screen blanking is active
- Launches the SteamLink-app
The script is configured to run as a service using systemd. The repository is here. It is kludged together and can probably benefit from some TLC, but it works!
#! /usr/bin/python3
from evdev import InputDevice, ecodes, list_devices, ff, categorize
import time
import subprocess
import random
import socket
MAC_ADDRESS_DESKTOP = 'd8:80:83:9c:5b:2f'
MAC_ADDRESS_TV = '48:8d:36:bc:e8:ec'
DEVICE_PATH = '/dev/input/event14'
IP_ADDRESS_TV = '192.168.1.43'
RETRY_INTERVAL = 3
BTN_A = ecodes.BTN_SOUTH
BTN_B = ecodes.BTN_EAST
BTN_COMBO = set([BTN_A, BTN_B])
COMBO_HOLD_TIME = 1.5 # Seconds
HDMI_INPUT = 'HDMI_2'
def main():
device = find_controller_device()
pressed_buttons = set()
combo_pressed_time = None
while True:
try:
for event in device.read_loop():
if event.type != ecodes.EV_KEY:
continue
key_event = categorize(event)
if key_event.keystate == key_event.key_down:
pressed_buttons.add(key_event.scancode)
if pressed_buttons == BTN_COMBO:
combo_pressed_time = time.time()
else:
combo_pressed_time = None
elif key_event.keystate == key_event.key_up:
if combo_pressed_time and (time.time() - combo_pressed_time >= COMBO_HOLD_TIME):
execute_commands(device)
combo_pressed_time = None
pressed_buttons.discard(key_event.scancode)
combo_pressed_time = None
except OSError as e:
if e.errno == 19: # 19 = No such device (disconnected)
print(f'Device disconnected. Reconnecting...')
device = find_controller_device()
else:
print(f'Unexpected error: {e}')
time.sleep(RETRY_INTERVAL)
def find_controller_device():
while True:
try:
devices = [InputDevice(path) for path in list_devices()]
for dev in devices:
if dev.path == DEVICE_PATH:
print(f'Device found: {dev.path}')
return InputDevice(DEVICE_PATH)
print(f'Device not found. Retrying in {RETRY_INTERVAL} seconds...')
time.sleep(RETRY_INTERVAL)
except Exception as e:
print(f'Error checking devices: {e}')
time.sleep(RETRY_INTERVAL)
def execute_commands(device):
print('Button combo detected! Running script...')
rumble_controller(device)
print('Waking TV....')
send_wol_packet(MAC_ADDRESS_TV)
print('Waking Desktop....')
send_wol_packet(MAC_ADDRESS_DESKTOP)
wake_screen()
start_steamlink()
print('Setting TV input')
set_tv_input()
print('Commands completed.')
def rumble_controller(device):
rumble = ff.Rumble(strong_magnitude=0xc000, weak_magnitude=0xc000)
duration_ms = 500
effect = ff.Effect(
ecodes.FF_RUMBLE,
-1,
0,
ff.Trigger(0, 0),
ff.Replay(duration_ms, 0),
ff.EffectType(ff_rumble_effect=rumble)
)
effect_id = device.upload_effect(effect)
repeat_count = 1
device.write(ecodes.EV_FF, effect_id, repeat_count)
time.sleep(0.5)
device.erase_effect(effect_id)
def send_wol_packet(mac_address):
mac_bytes = bytes.fromhex(mac_address.replace(':', ''))
magic_packet = b'\xff' * 6 + mac_bytes * 16
# TV will sometimes not respond, so we spam WoL a bit.
for _ in range(10):
with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock:
sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
sock.sendto(magic_packet, ('<broadcast>', 9))
def wake_screen():
# If TV is ON, but media-PC has blanked the screen/screensaver, move the mouse a bit.
x, y = random.randint(0, 10), random.randint(0, 10)
subprocess.run(['ydotool', 'mousemove', str(x), str(y)], stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
def start_steamlink():
try:
result = subprocess.run(
['pgrep', '-f', 'com.valvesoftware.SteamLink'],
stdout=subprocess.PIPE,
stderr=subprocess.PIPE
)
if result.stdout:
print('SteamLink is already running, skipping launch.')
else:
print('Starting SteamLink...')
with open('/home/sverrejb/workspace/gamestart/steamlink.log', 'a') as log_file:
subprocess.Popen(
'QT_QPA_PLATFORM=wayland WAYLAND_DISPLAY=wayland-0 flatpak run com.valvesoftware.SteamLink',
shell=True,
stdout=log_file,
stderr=subprocess.STDOUT,
start_new_session=True,
env={
'QT_QPA_PLATFORM': 'wayland',
'WAYLAND_DISPLAY': 'wayland-0',
'XDG_RUNTIME_DIR': '/run/user/1000'
}
)
except Exception as e:
print(f'Error checking for SteamLink process: {e}')
def set_tv_input():
try:
subprocess.run(['/home/sverrejb/.local/bin/alga', 'input', 'set', HDMI_INPUT], check=True)
except:
print('Initial HDMI-switch failed. Trying harder.')
while True:
response = subprocess.run(['ping', '-c', '1', '-W', '1', IP_ADDRESS_TV], stdout=subprocess.PIPE)
if response.returncode == 0:
print('TV is responding to ping.')
break
else:
print('Waiting for TV to respond to ping...')
time.sleep(1)
time.sleep(10)
for i in range(5):
print(f'Setting HDMI-input {i+1}/5')
subprocess.run(['/home/sverrejb/.local/bin/alga', 'input', 'set', HDMI_INPUT])
time.sleep(0.2)
if __name__ == '__main__':
try:
main()
except KeyboardInterrupt:
print('Exiting...')