enricobuehler
ae35e8b4d7
`XBOX_RDESC` is the only report descriptor in `pf-gamepad` that was hand-written rather than
captured off hardware, and its own provenance warning has now come true three times. The fix for
that class of bug is not another careful reading — it is a tool that goes and asks the device.
`tools/hid-descriptor-dump` does that: it dumps a real HID device's report descriptor, decodes it
into an annotated item listing plus a bit-offset LAYOUT TABLE, and can decode a blob we already
ship through the same decoder (`--rust-source <file> --symbol <NAME>`) so the two are diffable
line for line. `--read N` pulls live wire bytes, which is the only ground truth a reconstructed
descriptor cannot give you.
Deliberately NOT a workspace member — it pulls `hidapi`, a C library wanting libudev on Linux,
which has no business in `cargo build --workspace` or on a CI leg with no pad attached. It is a
bring-your-own-hardware tool and it is excluded in the root manifest, so CI never sees it.
The captured Elite disagrees with our blob in four ways, and the dangerous one is field ORDER:
the real pad reports sticks, ONE combined 16-bit Z trigger, then BUTTONS, then the hat, in an
UNNUMBERED 15-byte report; ours declares Report ID 1, two Simulation-page trigger axes, then the
hat, then 15 buttons. Since we claim a genuine Microsoft VID/PID and SDL/Steam/Windows all apply
stock mappings keyed on it, that ordering difference is exactly how every control silently lands
on the wrong action. The driver comment now records the diff and the two blockers that stop the
capture from simply being pasted in.
VERIFIED
* `cargo fmt --check` clean, `cargo clippy --all-targets -- -D warnings` clean (macOS).
* The tool builds and runs on macOS and on .173 (Windows 11 26200, cargo 1.96, MSVC, no WDK).
* TOOL VALIDATED AGAINST A KNOWN-GOOD CONTROL: pointed at the live DualSense on .173, it
reproduces the real `DUALSENSE_RDESC` layout exactly (input 0x01, 64 B, X,Y,Z,Rz,Rx,Ry at
bytes 1..6, hat 8.0, 15 buttons 8.4, output 0x02, the full feature ladder), and `--read`
returned live len=64 reports with sticks centred at 80 80 80 80 and the counter incrementing.
* `cargo metadata` on the root workspace still resolves and does NOT list this crate.
* The Elite capture is reproducible: `--vid 045E --pid 0B22`.
NOT VERIFIED
* That the capture equals the pad's NATIVE report map. Windows exposes no API for a device's
literal descriptor bytes, so hidapi reconstructs from `HidD_GetPreparsedData` — faithful in
structure, item order and bit offsets, not byte-exact (measured: the DualSense's real 273-byte
descriptor reconstructs to 467). `xinputhid` also filters that pad, and the captured shape is
the legacy DirectInput view. A byte-exact answer needs Linux hidraw.
* Why the Elite returned ZERO input reports across two runs (72 s and 90 s) while the DualSense
streamed fine on the same code path — untouched pad, or exclusive claim by the XInput
translator. Unresolved.
* Nothing here was built on Windows as a driver: `XBOX_RDESC` itself is UNCHANGED, so no
behaviour changes. The only edit to the driver is its provenance comment.
Packaging punktfunk for Fedora / Bazzite
The punktfunk host links system FFmpeg (NVENC on NVIDIA, VAAPI on AMD/Intel, with a GPU-less software-H.264 fallback), PipeWire and Opus. This page covers packaging it for the Fedora Atomic / Bazzite world (rpm-ostree + bootc), where most of those deps are already present; the NVIDIA-specific notes below apply to the NVENC path.
👉 Ubuntu/Debian hosts install via
aptfrom Gitea's package registry — seedebian/README.md(apt update && apt upgradefor new builds).
👉 End-to-end Bazzite setup walkthrough (install → udev/group →
host.env→ service → firewall → verify → troubleshooting):bazzite/README.md. This file is the higher-level packaging rationale.
packaging/
rpm/punktfunk.spec # the RPM (builds punktfunk-host from source with cargo)
bazzite/host.env # gamescope-default config for a Bazzite appliance
bazzite/README.md # step-by-step Bazzite setup guide
bazzite/*sysext*.sh # the no-layering path: build/install/publish the systemd-sysext
bootc/Containerfile # bake punktfunk into a Bazzite-based atomic image
copr/ # COPR build-from-SCM settings
The other packaging targets have their own READMEs: debian/ (apt),
arch/ (pacman binary repo + PKGBUILD + SteamOS sysext),
flatpak/ (the client), windows/ (host installer +
drivers), plus kde/ and linux/ helpers. NixOS / Nix users get a flake (flake.nix at the
repo root) with reproducible host + client packages and a services.punktfunk NixOS module —
see nix/README.md.
What's needed beyond base Fedora
| Dependency | Where it comes from |
|---|---|
ffmpeg-libs with NVENC |
RPM Fusion nonfree (ffmpeg, not ffmpeg-free) |
NVIDIA driver (libnvidia-encode, libEGL_nvidia) |
Bazzite -nvidia images ship it; plain Fedora: akmod-nvidia + xorg-x11-drv-nvidia-cuda |
| gamescope, PipeWire, wireplumber | Bazzite ships these; plain Fedora: dnf install gamescope pipewire wireplumber |
opus, libei |
Fedora base / updates |
On Bazzite the only genuinely new runtime bits are ffmpeg-libs (RPM Fusion) + opus +
libei — the rest of the stack is already there. The default backend is gamescope
(packaging/bazzite/host.env), which the host spawns headless per session — no desktop login.
Option A — systemd-sysext (recommended; no layering, no reboot)
On Bazzite / Fedora Atomic the recommended install is the systemd-sysext image — rpm-ostree
layering is a last resort per the Bazzite docs (it slows every OS update and can block upgrades),
while a sysext overlays /usr at runtime, survives OS updates, and updates in one command with
no reboot. CI wraps the same RPMs below into the image, so content and channels are identical.
curl -fsSLO https://git.unom.io/unom/punktfunk/raw/branch/main/packaging/bazzite/punktfunk-sysext.sh
sudo bash punktfunk-sysext.sh install # then: sudo punktfunk-sysext update | status | remove
Full walkthrough (incl. the F43→F44 rebase behavior and migration off layering):
bazzite/README.md.
Option B — Gitea RPM registry (per-host, rpm-ostree layering)
The host's RPM is published to unom's self-hosted Gitea RPM registry (CI builds it on every
push), mirroring the Debian/apt setup. Add one repo file, install, and track
updates with rpm-ostree upgrade — no COPR account needed. Full guide: rpm/README.md.
# GPG-signed pkgs + Gitea-signed metadata → gpgcheck=1, repo_gpgcheck=1 (see rpm/README.md)
sudo tee /etc/yum.repos.d/punktfunk.repo >/dev/null <<'REPO'
[gitea-unom-bazzite]
name=punktfunk (unom, Bazzite)
baseurl=https://git.unom.io/api/packages/unom/rpm/bazzite
enabled=1
gpgcheck=1
repo_gpgcheck=1
gpgkey=https://git.unom.io/api/packages/unom/rpm/repository.key
https://git.unom.io/api/packages/unom/generic/punktfunk-keys/1/RPM-GPG-KEY-punktfunk
REPO
rpm-ostree install punktfunk && systemctl reboot
# updates: rpm-ostree upgrade && systemctl reboot
Option C — COPR (per-host, rpm-ostree install)
- Create a COPR project, enable build-from-SCM pointing at this repo, spec path
packaging/rpm/punktfunk.spec(seecopr/README.md). Under External Repositories add RPM Fusion nonfree soffmpeg-develresolves at build time. - On the Bazzite host:
# RPM Fusion (for the NVENC ffmpeg) — usually already enabled on Bazzite rpm-ostree install \ https://mirrors.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm \ https://mirrors.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm # enable the COPR + install punktfunk sudo wget -O /etc/yum.repos.d/_copr_punktfunk.repo \ https://copr.fedorainfracloud.org/coprs/enricobuehler/punktfunk/repo/fedora-$(rpm -E %fedora)/ rpm-ostree install punktfunk systemctl reboot
Option D — bootc (image-based, atomic)
Layer punktfunk into a Bazzite image once, then rebase any number of hosts onto it — no
per-host drift. See bootc/Containerfile:
podman build -t ghcr.io/<you>/bazzite-punktfunk -f packaging/bootc/Containerfile .
podman push ghcr.io/<you>/bazzite-punktfunk
# on the target:
sudo bootc switch ghcr.io/<you>/bazzite-punktfunk && systemctl reboot
First-run setup (all options)
ujust add-user-to-input-group # virtual gamepads need /dev/uinput (then re-login).
# On Bazzite use ujust, NOT `usermod -aG input` (atomic OS — it won't stick).
mkdir -p ~/.config/punktfunk
cp /usr/share/punktfunk/host.env.bazzite ~/.config/punktfunk/host.env # edit (gamescope app, etc.)
systemctl --user enable --now punktfunk-host
# Management web console (pairing + status) — pulled in by default (the host RPM Recommends it;
# `--no-install-recommends` / headless-only boxes can skip it). Enable it and read the login password:
systemctl --user enable --now punktfunk-web
journalctl --user -u punktfunk-web-init | sed -n 's/.*password generated: //p' # then open https://<host-ip>:47992
Pair a stock Moonlight client (mDNS-discovered), or connect the native punktfunk/1 client — via the
web console at https://<host-ip>:47992 or directly.
⚠️ COPR caveat: COPR's mock chroot has no
bun, so a COPR build produces onlypunktfunk+punktfunk-client— notpunktfunk-web. For the console on a COPR/bootc host, install from the Gitea RPM registry (Option B — it carriespunktfunk-web; the sysext image includes it too), which is also whybootc/Containerfileinstalls from there rather than COPR.
Why not Flatpak (for the HOST)?
The host needs unsandboxed access the zero-copy NVENC path, /dev/uinput, the PipeWire
graph and the compositor's privileged protocols — a Flatpak sandbox fights all of these.
An RPM (or the bootc layer) installs into the host system where those just work.
👉 The client is a different story — it IS shipped as a Flatpak (the only viable Steam Deck install path: SteamOS
/usris read-only and lackslibadwaita/libSDL3). Seeflatpak/README.md. The client sandbox only needs the GPU render node, Wayland, PipeWire audio, the network and hidraw — all expressible as finish-args.
Building the SRPM/RPM locally (Fedora only)
git archive --format=tar.gz --prefix=punktfunk-0.3.0/ -o ~/rpmbuild/SOURCES/punktfunk-0.3.0.tar.gz HEAD
rpmbuild -ba packaging/rpm/punktfunk.spec # needs the BuildRequires from the spec
# (0.3.0 = the spec's default %{pf_version}; the prefix and tarball name must match it)
(Not buildable on Debian/Ubuntu — use a Fedora toolbox/container or COPR.)