The virtual Deck's gamepad evdev was churning (destroyed + recreated) because
Steam kept re-probing: GetControllerInfo reads HID feature reports, and the gadget
served zeros for them. Captured the real contract off a physical Deck
(packaging/linux/steam-deck-gadget/get_deck_attrs.c, hidraw HIDIOCGFEATURE — usbmon
truncates to 32B) and implemented it in steam_gadget.rs::feature_reply:
- 0x83 GET_ATTRIBUTES_VALUES: [83, 2d, 9×(attr-id, u32-LE)] — product id 0x1205, a
per-instance unit serial (0x0a/0x04, so a gadget never collides with a real Deck
or another gadget), and the capability attrs (0x09=0x2e, 0x0b=0x0fa0, rest 0).
- 0xAE GET_STRING_ATTRIBUTE: [ae, len, attr, ascii] — serial (attr 1) / board
serial (attr 0).
- other commands (0x87 settings): echo the last write.
Validated on the Deck: 1 connect / 0 disconnect / 1 gamepad evdev (was constant
churn), Steam activates the gadget cleanly (no GetControllerInfo failed, no zombie)
and emits its X-Box 360 pad. usbmon on the gadget's bus confirms our state reports
(pressed button at byte 8) are delivered on the interrupt-IN and consumed by
hid-steam — so with M1/M2's byte-8→BTN_SOUTH decode the input chain is proven
end-to-end. Remaining: a foreground-game confirmation of Steam Input's XInput
mapping, then default the gadget on for SteamOS.
Workspace clippy/fmt/test green. Not pushed.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Port the proven raw_gadget virtual Deck to a Rust host gamepad backend, the
SteamOS-only transport that gets Steam Input to actually promote the Deck.
- inject/linux/steam_gadget.rs (new): SteamDeckGadget — a userspace raw_gadget
emulator of the real 3-interface USB Deck (mouse=0/keyboard=1/controller=2,
28DE:1205) on a dummy_hcd loopback UDC, descriptors captured from a physical
Deck, answering every control transfer incl. the HID feature reports. Driven by
the same steam_proto::serialize_deck_state as the UHID pad; rumble feedback via
parse_steam_output. The raw_gadget UAPI is funneled through 4 documented ioctl
wrappers (the crate denies undocumented unsafe).
- inject/linux/steam_controller.rs: the manager pad is now a DeckTransport enum
(Uhid | Gadget); ensure() prefers the gadget when PUNKTFUNK_STEAM_GADGET=1
(best-effort modprobe dummy_hcd+raw_gadget), gracefully falling back to the
universal UHID SteamDeckPad. write/pump/heartbeat dispatch through the enum.
Validated on a real Deck via a static musl harness that #[path]-includes the
module: enumerates, hid-steam binds + reads our serial + creates the Steam Deck +
Motion Sensors evdevs — identical to the C PoC. Caught a real portability bug:
raw_gadget's no-arg ioctls (RUN/CONFIGURE/EP0_STALL) reject a non-zero `value`
with EINVAL, and on musl an omitted ioctl vararg is a garbage register — so they
must pass an explicit 0.
Opt-in (default off) while the Steam GetControllerInfo feature contract is
hardened (to stop the gamepad-evdev churn). Workspace clippy/fmt/test green. Not pushed.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
The interface-2 wall is climbed. packaging/linux/steam-deck-gadget/deck_raw_gadget.c
is a raw_gadget userspace emulator of a real 3-interface USB Steam Deck (28DE:1205,
mouse=0/keyboard=1/controller=2) on a dummy_hcd loopback UDC, with descriptors
captured verbatim from a physical Deck and full HID feature-report handling.
Live on a real Deck (SteamOS 3.8.11): hid-steam reads our serial (PFDECK000),
creates the Steam Deck + Motion Sensors evdevs, and Steam Input PROMOTES it —
controller.txt "Interface: 2 ... device opened ... reserving XInput slot 1" +
"input: Microsoft X-Box 360 pad 1". Stable (1 connect, 0 disconnects, no zombie);
the kernel Steam Deck evdev is then grabbed by Steam Input which exposes its own
X-Box pad, exactly like a real Deck. First time a virtual Deck is fully Steam-Input
promoted (UHID can't — it has no USB interface number, so Steam filters it).
Also includes the configfs f_hid variant (configfs_gadget_up/down.sh) — the minimal
reproducer that proved interface 2 makes Steam open+XInput-reserve the device, but
f_hid can't serve feature reports so Steam dropped it as a zombie.
Gotchas documented in the README: 7-byte vs 9-byte endpoint descriptor, no-data OUT
controls acked via zero-length EP0_READ (not WRITE, else error -110), streamer must
not start before SET_CONFIGURATION is acked. SteamOS-host only (needs dummy_hcd +
raw_gadget). Recognition proven; feeding real client reports + a host backend is next.
Not pushed.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Streaming the KDE *Desktop* (KWin) session failed on a real interactive
Plasma session with "KWin does not expose zkde_screencast_unstable_v1":
KWin treats the screencast/virtual-output and fake_input globals as
restricted and advertises them only to a client whose installed .desktop
lists them under X-KDE-Wayland-Interfaces (matched by /proc/<pid>/exe ->
Exec, and cached per-executable on first connect). The host shipped no
.desktop, so it was permanently denied; it only ever worked on the
headless dev box via KWIN_WAYLAND_NO_PERMISSION_CHECKS=1.
Ship packaging/linux/io.unom.Punktfunk.Host.desktop (least-privilege:
only the host, only zkde_screencast_unstable_v1 + org_kde_kwin_fake_input)
and install it from the RPM/.deb/Arch host packaging so it is present
before the host first connects. Drop the blunt session-wide
NO_PERMISSION_CHECKS hack from kde-desktop-setup.sh (it now only seeds the
RemoteDesktop input grant) and fix the now-misleading kwin.rs docs/errors.
Validated live on a Bazzite Kinoite box (KWin 6.6.4): probe-compositor +
spike --source kwin-virtual succeed against a KWin running WITHOUT the
permission bypass.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Hook the Linux client into the existing packaging CI:
- deb.yml builds both binaries and publishes punktfunk-host AND
punktfunk-client to the Gitea apt registry; new
packaging/debian/build-client-deb.sh mirrors the host script
(shlibdeps auto-Depends — GTK4/libadwaita/SDL3/FFmpeg/PipeWire
sonames; no NVIDIA filter, the client links no CUDA). Built and
inspected locally on Ubuntu 26.04.
- punktfunk.spec gains a "client" subpackage (binary + desktop entry +
udev rule); rpm.yml's publish loop picks it up unchanged.
- New shared assets: packaging/linux/io.unom.Punktfunk.desktop and
scripts/70-punktfunk-client.rules — DualSense hidraw uaccess (USB +
Bluetooth, steam-devices style) so SDL's HIDAPI driver gets
touchpad/motion/lightbar/triggers instead of degrading to evdev.
- Builder images learn the client link deps (rust-ci already had
them; fedora-rpm adds gtk4/libadwaita/SDL3-devel) with idempotent
install steps in deb.yml/rpm.yml since jobs run against the
previous push's image.
Workspace check CI (build/clippy/test) already covers the crate since
f09def4.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>