bc250-ha-bridge

Expose an AMD BC-250 gaming PC (Cyan Skillfish, running Bazzite or another Linux with the cyan-skillfish-governor-smu GPU governor) to Home Assistant over MQTT, with sensors, a few controls, and a ready-made dashboard.

One small Python script, standard library only. No pip, no containers, nothing installed system-wide besides a systemd unit (and optionally a polkit rule).

Built for one specific, heavily modified board. Read Safety before enabling the Advanced controls.

The bc250-card custom card, as it looks in Home Assistant.

Online	Machine off or asleep	Advanced panel open

When the machine is off, everything is locked except Wake up. Destructive buttons ask for confirmation, and the GPU clock panel is collapsed unless show_advanced: true.

The background photo and the frosted-glass theme in these screenshots are personal choices and are not part of this repo (the card itself has a glass: true option for a similar look).

What you get

Sensors (HA MQTT discovery, published every 30 s): CPU / GPU / NVMe temperature, GPU clock, GPU load, pump RPM, RAM / swap / disk use, uptime, current Steam game, active CU count (from the CU manager config), configured voltage at the current max clock, governor throttle temperature, current GPU min/max range.

Controls: Sleep, Reboot, Shut down, Restart Steam, Switch to Desktop / Game mode, Close current game, and an [Advanced] GPU min/max clock range with a Reset button.

Availability: the device shows unavailable in HA when the machine is asleep or off (MQTT last-will). Wake it with HA's Wake on LAN integration (see below).

Requirements

• An MQTT broker reachable from the PC (for example the Mosquitto add-on in Home Assistant) and an MQTT user for the bridge.
• Python 3.11+ (tomllib) and systemd.
• Optional: cyan-skillfish-governor-smu for the GPU clock features. Without it those entities report nothing.

Install

git clone https://github.com/phiiaz/bc250-ha-bridge ~/bc250-ha-bridge

# 1. credentials (never commit the real file)
mkdir -p ~/.config/bc250-ha-bridge
cp ~/bc250-ha-bridge/env.example ~/.config/bc250-ha-bridge/env
chmod 600 ~/.config/bc250-ha-bridge/env && $EDITOR ~/.config/bc250-ha-bridge/env

# 2. try it without touching the network, then once against the broker
python3 -I ~/bc250-ha-bridge/publisher.py --dry-run
python3 -I ~/bc250-ha-bridge/publisher.py --once

# 3. run it as a service (edit YOUR_USER first)
sudo cp ~/bc250-ha-bridge/systemd/bc250-ha-bridge.service /etc/systemd/system/
sudo systemctl daemon-reload && sudo systemctl enable --now bc250-ha-bridge
journalctl -u bc250-ha-bridge -f

A device named Bazzite BC-250 appears under Settings → Devices & Services → MQTT.

Power buttons need a polkit rule

The service has no login session, so systemctl reboot/poweroff/suspend would be refused. polkit/50-bc250-ha-bridge-power.rules allows exactly those three actions for one user (not the *-ignore-inhibit variants). Edit YOUR_USER, then:

sudo cp polkit/50-bc250-ha-bridge-power.rules /etc/polkit-1/rules.d/

Skip it if you do not want the power buttons; they will just log an error.

Dashboard card

The dashboard is a single custom Lovelace card, custom:bc250-card (source in card/, built file in dist/bc250-card.js). Pick the device and you get vitals gauges, history graphs, system tiles, power/session buttons (destructive ones ask for confirmation) and an optional, collapsed Advanced panel for the GPU clock range.

Install with HACS: HACS → ⋮ → Custom repositories → add https://github.com/phiiaz/bc250-ha-bridge, category Dashboard, then download BC-250 Card and reload the browser.

Or manually: copy dist/bc250-card.js to /config/www/bc250-card.js, add a resource (Settings → Dashboards → Resources) with URL /local/bc250-card.js, type JavaScript module.

Add the card from the card picker (visual editor), or in YAML:

type: custom:bc250-card
device_id: YOUR_DEVICE_ID          # required: the "Bazzite BC-250" device
wol_entity: button.wake_on_lan     # optional: your Wake on LAN button, enables "Wake up"
show_advanced: false               # GPU clock range panel (collapsed by default)
show_history: true
history_hours: 6
confirm_actions: true
glass: false                       # frosted-glass look
# name, accent_color, background_color, sections: [header, vitals, history, system, actions]

device_id is the device registry ID: select the device in the editor, or copy it from the device page URL. Entities are found by their unique_id, falling back to the default entity names, so renamed entities keep working (the unique_id lookup needs an admin user). homeassistant/dashboard.yaml is a ready dashboard containing just this card. homeassistant/dashboard-legacy.yaml is the old stock-cards dashboard, deprecated and kept for one release.

The card only validates the clock range for convenience: publisher.py still enforces the limits on the machine.

Build it yourself: cd card && npm install && npm test && npm run build.

Wake on LAN

Enable magic-packet wake on the NIC, persistently, with NetworkManager:

nmcli connection modify "Wired connection 1" 802-3-ethernet.wake-on-lan magic

Then add HA's Wake on LAN integration with the PC's MAC address. Whether the board wakes from sleep or from a full shutdown depends on its BIOS. Test both.

ESPHome RLCD Desk Remote (Optional)

esphome/bazzite-rlcd-remote.yaml turns a Waveshare ESP32-S3-RLCD-4.2 (4.2" 400×300 monochrome reflective LCD, zero backlight power) into a desk status monitor and Wake / Shut down remote via Home Assistant:

Online	Shut down confirmation (2-step)
Offline (ready to wake)	Wake-on-LAN sent

• Screen: online/offline status, current Steam game, 6-tile vitals grid (CPU/GPU temp, GPU load, GPU clock, RAM used, pump RPM), onboard SHTC3 room temperature/humidity, and 18650 battery percentage.
• Buttons:
  • When offline, pressing KEY (GPIO18) or BOOT (GPIO0) triggers button.wake_on_lan.
  • When online, pressing KEY once arms a 5-second confirmation banner; pressing KEY a second time triggers button.bazzite_shut_down (BOOT cancels).

Flash with ESPHome (cp esphome/secrets.yaml.example esphome/secrets.yaml && esphome run esphome/bazzite-rlcd-remote.yaml), then in Home Assistant (Settings → Devices & Services → ESPHome → Configure) enable "Allow the device to perform Home Assistant actions".

Safety

• GPU clock control: limits are enforced inside publisher.py (BRIDGE_CLOCK_FLOOR / BRIDGE_CLOCK_CEIL, default 1000 to 2200 MHz, steps of 50), not only in HA. The default ceiling is the author's own tested value on one board. Set yours. Changes go through the governor's runtime D-Bus interface, are not persisted, and reset on a governor restart or reboot. The governor config file is never touched.
• Voltage and CU count are read-only on purpose. There is no runtime interface for them and a wrong value can hang the machine.
• Commands come from a fixed whitelist. MQTT payloads never reach a shell.
• Use a dedicated, LAN-only MQTT user with a strong password.
• "Close current game" sends SIGTERM to Steam's reaper process for the running game. It does not force-kill, and unsaved progress is lost.

Known limits

• GPU load is an average over the 30 s sampling window, not a live gauge.
• "Current Steam game" only sees games launched through Steam.
• While the PC sleeps, the bridge is frozen; it reconnects about 15 s after waking.

Files

Path	Purpose
publisher.py	The bridge (sensors, controls, MQTT discovery)
env.example	Credentials template
systemd/bc250-ha-bridge.service	System unit
polkit/50-bc250-ha-bridge-power.rules	Optional power-control permission
card/	Source of the bc250-card Lovelace card (TypeScript + Lit)
dist/bc250-card.js	Built card (what HACS / /local serves)
hacs.json	HACS metadata (Dashboard category)
homeassistant/dashboard.yaml	Dashboard with the card
homeassistant/dashboard-legacy.yaml	Deprecated stock-cards dashboard
esphome/bazzite-rlcd-remote.yaml	Optional ESPHome config for Waveshare ESP32-S3-RLCD-4.2
esphome/secrets.yaml.example	ESPHome credentials template

License

MIT, see LICENSE.