# nvidia-power-tray

A tray indicator showing the PCI power state of the NVIDIA GPU — `D0` when the
card is awake, `D3cold` when the driver has runtime-suspended it. Useful on
hybrid-graphics laptops to see at a glance whether something is holding the
discrete GPU on.

The state is read from `/sys/bus/pci/devices/<address>/power_state`. That is a
plain sysfs read and does not wake a suspended card — unlike `nvidia-smi` or
`lspci`, both of which touch the device and pull it back into `D0`. For the
same reason the device name in the menu is resolved from `/usr/share/misc/pci.ids`
instead of by shelling out to `lspci`.

## Contents

```text
.local/bin/nvidia-power-tray                     # the indicator
.config/systemd/user/nvidia-power-tray.service   # runs it in the GNOME session
```

## Dependencies

- GNOME with the [AppIndicator support extension](https://extensions.gnome.org/extension/615/appindicator-support/)
  (`appindicatorsupport@rgcjonas.gmail.com`) — GNOME Shell has no tray of its own
- `gir1.2-ayatanaappindicator3-0.1`, `gir1.2-gtk-3.0`, `python3-gi`
- `pciutils` for `/usr/share/misc/pci.ids` (already present on Debian)

```bash
sudo apt install gir1.2-ayatanaappindicator3-0.1 gir1.2-gtk-3.0 python3-gi
```

The script also accepts the older `AppIndicator3` namespace if that is what the
system ships.

## Install

```bash
cd ~/dotfiles
stow nvidia-power-tray
systemctl --user daemon-reload
systemctl --user enable --now nvidia-power-tray.service
```

The unit is `WantedBy=graphical-session.target`, so it starts with the GNOME
session and stops with it.

## Usage

The icon reflects the state (`power-profile-performance-symbolic` for `D0`,
`power-profile-power-saver-symbolic` for `D3hot`/`D3cold`) and the label next to
it is the raw state string. The menu shows the device, PCI address, bound
driver, power state, runtime-PM status and runtime-PM control setting, plus
`Refresh now` and `Quit`.

The PCI address is autodetected: the first NVIDIA (vendor `0x10de`) display
controller, preferring one with a driver bound. Override it, or the 5 second
poll interval, with flags or environment variables:

```bash
nvidia-power-tray --address 0000:01:00.0 --interval 10
NVIDIA_POWER_TRAY_ADDRESS=0000:01:00.0 NVIDIA_POWER_TRAY_INTERVAL=10 nvidia-power-tray
```

`nvidia-power-tray --print` prints `<address> <state>` once and exits without
touching GTK — handy for testing or for a shell prompt/status bar.

## Troubleshooting

```bash
systemctl --user status nvidia-power-tray.service
journalctl --user -u nvidia-power-tray.service -f
```

If the service runs but no icon appears, the AppIndicator extension is probably
disabled: `gnome-extensions list --enabled | grep appindicator`.
