feat(gamepad): virtual DualSense on the Windows host (UMDF shm channel)

Wire the Windows UMDF DualSense driver into the host as a real pad backend, so a
client that requests a DualSense gets a genuine one on a Windows host (instead of
folding to Xbox 360).

- Extract the transport-independent DualSense contract (DsState + from_gamepad,
  serialize_state, parse_ds_output, DUALSENSE_RDESC, feature blobs, DS_* consts)
  out of the Linux-only UHID backend into inject/dualsense_proto.rs, shared by both
  platforms; dualsense.rs is now just the /dev/uhid plumbing.
- Add inject/dualsense_windows.rs: DualSenseWindowsManager mirroring the Linux
  DualSenseManager (same new/handle/apply_rich/pump/heartbeat surface) over a
  DsWinPad that creates the Global\pfds-shm-<idx> section (CreateFileMappingW +
  SDDL D:(A;;GA;;;WD) so WUDFHost can open it), writes serialize_state -> input
  slot, polls output_seq -> parse_ds_output -> rumble/hidout callbacks.
- Un-gate the seam: PadBackend::DualSenseWindows arm; pick_gamepad gains a
  windows flag (DualSense honored on linux||windows; DS4/Xbox One stay Linux-only).

Verified: Linux cargo test gamepad_resolution_precedence + clippy clean; Windows
cargo check + clippy -D warnings clean (on the RTX box). Device lifecycle still
uses an out-of-band devnode (devgen/installer); SwDeviceCreate per session is next.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit is contained in:
2026-06-21 20:36:53 +00:00
parent aa159df33f
commit 4a73102d48
8 changed files with 896 additions and 487 deletions
@@ -0,0 +1,331 @@
//! Virtual Sony DualSense on Windows via the UMDF minidriver (`packaging/windows/dualsense-driver`).
//!
//! The Windows analogue of the Linux UHID backend ([`super::dualsense`]): same [`DsState`] model and
//! the same byte-level report codec ([`super::dualsense_proto`]), but a different transport. Where
//! the Linux backend writes report `0x01` to `/dev/uhid` and reads report `0x02` via `UHID_OUTPUT`,
//! the Windows backend talks to the UMDF driver over a **named shared-memory section**
//! `Global\pfds-shm-<idx>` (256 B: magic `u32@0`, input report `@8`, output seq `u32@72`, output
//! report `@76`). The host creates the section (privileged → a permissive SDDL so the WUDFHost can
//! open it); the driver maps it from its timer, feeds game `READ_REPORT`s from the input bytes, and
//! publishes a game's `0x02` (rumble / lightbar / player-LEDs / adaptive triggers) into the output
//! bytes. `hidclass` gates the device stack, so this user-mode IPC is the only viable channel (a
//! UMDF driver has no control device); see `windows-dualsense-scoping.md`.
//!
//! Device lifecycle: the `root\pf_dualsense` devnode is currently created out-of-band (the dev-box
//! `devgen` for tests; the installer for fleet use). Per-session creation via `SwDeviceCreate` (so the
//! pad appears/disappears with the session, matching the Linux UHID lifecycle) is the next step —
//! see [`DsWinPad::open`].
use super::dualsense_proto::{
parse_ds_output, serialize_state, DsFeedback, DsState, DS_INPUT_REPORT_LEN, DS_TOUCH_H,
DS_TOUCH_W,
};
use crate::gamestream::gamepad::{GamepadEvent, MAX_PADS};
use anyhow::{anyhow, Result};
use punktfunk_core::quic::{HidOutput, RichInput};
use std::ffi::c_void;
use std::time::{Duration, Instant};
use windows::core::{w, HSTRING, PCWSTR};
use windows::Win32::Foundation::{CloseHandle, HANDLE, INVALID_HANDLE_VALUE};
use windows::Win32::Security::Authorization::{
ConvertStringSecurityDescriptorToSecurityDescriptorW, SDDL_REVISION_1,
};
use windows::Win32::Security::{PSECURITY_DESCRIPTOR, SECURITY_ATTRIBUTES};
use windows::Win32::System::Memory::{
CreateFileMappingW, MapViewOfFile, UnmapViewOfFile, FILE_MAP_ALL_ACCESS,
MEMORY_MAPPED_VIEW_ADDRESS, PAGE_READWRITE,
};
/// Shared-section layout — must match `packaging/windows/dualsense-driver/src/lib.rs`.
const SHM_SIZE: usize = 256;
const SHM_MAGIC: u32 = 0x5046_4453; // "PFDS"
const OFF_INPUT: usize = 8;
const OFF_OUT_SEQ: usize = 72;
const OFF_OUTPUT: usize = 76;
/// A single virtual DualSense: the shared-memory section the driver maps (and, in future, the
/// `HSWDEVICE` from `SwDeviceCreate`). Dropping it unmaps + closes the section.
struct DsWinPad {
map: HANDLE,
view: *mut u8,
seq: u8,
ts: u32,
last_out_seq: u32,
}
impl DsWinPad {
/// Create + map the section `Global\pfds-shm-<index>` and stamp the magic so the driver accepts
/// it. (TODO: also `SwDeviceCreate("root\\pf_dualsense")` here to spawn the devnode per session;
/// for now the devnode is created out-of-band by the installer / dev-box `devgen`.)
fn open(index: u8) -> Result<DsWinPad> {
let name = HSTRING::from(format!("Global\\pfds-shm-{index}"));
// A permissive DACL so the WUDFHost (whatever account it runs as) can open the section.
let mut psd = PSECURITY_DESCRIPTOR::default();
// SAFETY: the SDDL literal is valid; psd receives an allocated descriptor (freed by the OS
// when the process exits — acceptable for a host-lifetime object).
unsafe {
ConvertStringSecurityDescriptorToSecurityDescriptorW(
w!("D:(A;;GA;;;WD)"),
SDDL_REVISION_1,
&mut psd,
None,
)?;
}
let sa = SECURITY_ATTRIBUTES {
nLength: std::mem::size_of::<SECURITY_ATTRIBUTES>() as u32,
lpSecurityDescriptor: psd.0,
bInheritHandle: false.into(),
};
// SAFETY: anonymous (pagefile-backed) section of SHM_SIZE bytes with the SDDL above.
let map = unsafe {
CreateFileMappingW(
INVALID_HANDLE_VALUE,
Some(&sa),
PAGE_READWRITE,
0,
SHM_SIZE as u32,
PCWSTR(name.as_ptr()),
)?
};
// SAFETY: map is a valid section handle; map the whole thing.
let view = unsafe { MapViewOfFile(map, FILE_MAP_ALL_ACCESS, 0, 0, SHM_SIZE) };
if view.Value.is_null() {
// SAFETY: map is valid.
unsafe {
let _ = CloseHandle(map);
}
return Err(anyhow!("MapViewOfFile failed for {name}"));
}
let base = view.Value as *mut u8;
// Zero the section then stamp the magic LAST (the driver only accepts it once magic is set).
// SAFETY: base points at SHM_SIZE writable bytes.
unsafe {
std::ptr::write_bytes(base, 0, SHM_SIZE);
std::ptr::write_unaligned(base.add(OFF_INPUT) as *mut [u8; DS_INPUT_REPORT_LEN], {
let mut r = [0u8; DS_INPUT_REPORT_LEN];
serialize_state(&mut r, &DsState::neutral(), 0, 0);
r
});
std::ptr::write_unaligned(base as *mut u32, SHM_MAGIC);
}
Ok(DsWinPad {
map,
view: base,
seq: 0,
ts: 0,
last_out_seq: 0,
})
}
/// Serialize `st` into report `0x01` and publish it to the section's input slot.
fn write_state(&mut self, st: &DsState) {
self.seq = self.seq.wrapping_add(1);
self.ts = self.ts.wrapping_add(1);
let mut r = [0u8; DS_INPUT_REPORT_LEN];
serialize_state(&mut r, st, self.seq, self.ts);
// SAFETY: view points at SHM_SIZE bytes; input slot is OFF_INPUT..OFF_INPUT+64.
unsafe { std::ptr::copy_nonoverlapping(r.as_ptr(), self.view.add(OFF_INPUT), r.len()) };
}
/// Poll the section's output slot; parse a new `0x02` report (rumble / LEDs / triggers) into a
/// [`DsFeedback`] for pad `pad`. Returns empty feedback if the driver hasn't published anything new.
fn service(&mut self, pad: u8) -> DsFeedback {
let mut fb = DsFeedback::default();
// SAFETY: view points at SHM_SIZE bytes.
let seq = unsafe { std::ptr::read_unaligned(self.view.add(OFF_OUT_SEQ) as *const u32) };
if seq != self.last_out_seq {
self.last_out_seq = seq;
let mut out = [0u8; 64];
// SAFETY: output slot is OFF_OUTPUT..OFF_OUTPUT+64 within the section.
unsafe {
std::ptr::copy_nonoverlapping(self.view.add(OFF_OUTPUT), out.as_mut_ptr(), 64)
};
parse_ds_output(pad, &out, &mut fb);
}
fb
}
}
impl Drop for DsWinPad {
fn drop(&mut self) {
// SAFETY: view came from MapViewOfFile; map from CreateFileMappingW.
unsafe {
let _ = UnmapViewOfFile(MEMORY_MAPPED_VIEW_ADDRESS {
Value: self.view as *mut c_void,
});
let _ = CloseHandle(self.map);
}
}
}
/// All virtual DualSense pads of a session — the Windows analogue of
/// [`DualSenseManager`](super::dualsense::DualSenseManager). Same method surface so the session input
/// thread drives either backend identically.
pub struct DualSenseWindowsManager {
pads: Vec<Option<DsWinPad>>,
state: Vec<DsState>,
last_rumble: Vec<(u16, u16)>,
last_write: Vec<Instant>,
broken: bool,
}
impl Default for DualSenseWindowsManager {
fn default() -> DualSenseWindowsManager {
DualSenseWindowsManager::new()
}
}
impl DualSenseWindowsManager {
pub fn new() -> DualSenseWindowsManager {
DualSenseWindowsManager {
pads: (0..MAX_PADS).map(|_| None).collect(),
state: vec![DsState::neutral(); MAX_PADS],
last_rumble: vec![(0, 0); MAX_PADS],
last_write: vec![Instant::now(); MAX_PADS],
broken: false,
}
}
/// Handle one decoded controller event (create/destroy by mask, then merge button/stick state).
pub fn handle(&mut self, ev: &GamepadEvent) {
match ev {
GamepadEvent::Arrival { index, kind, .. } => {
tracing::info!(index, kind, "controller arrival (DualSense/Windows)");
self.ensure(*index as usize);
}
GamepadEvent::State(f) => {
let idx = f.index as usize;
if idx >= MAX_PADS {
return;
}
for (i, slot) in self.pads.iter_mut().enumerate() {
if slot.is_some() && f.active_mask & (1 << i) == 0 {
tracing::info!(index = i, "controller unplugged (DualSense/Windows)");
*slot = None;
self.state[i] = DsState::neutral();
self.last_rumble[i] = (0, 0);
}
}
if f.active_mask & (1 << idx) == 0 {
return;
}
self.ensure(idx);
let prev = self.state[idx];
let mut s = DsState::from_gamepad(
f.buttons,
f.ls_x,
f.ls_y,
f.rs_x,
f.rs_y,
f.left_trigger,
f.right_trigger,
);
s.touch = prev.touch;
s.gyro = prev.gyro;
s.accel = prev.accel;
self.state[idx] = s;
self.write(idx);
}
}
}
/// Apply one rich client→host event (touchpad contact / motion sample) to an existing pad.
pub fn apply_rich(&mut self, rich: RichInput) {
let idx = match rich {
RichInput::Touchpad { pad, .. } | RichInput::Motion { pad, .. } => pad as usize,
};
if idx >= MAX_PADS || self.pads[idx].is_none() {
return;
}
match rich {
RichInput::Touchpad {
finger,
active,
x,
y,
..
} => {
let slot = (finger as usize).min(1);
let t = &mut self.state[idx].touch[slot];
t.active = active;
t.id = slot as u8;
t.x = ((x as u32 * (DS_TOUCH_W - 1) as u32) / u16::MAX as u32) as u16;
t.y = ((y as u32 * (DS_TOUCH_H - 1) as u32) / u16::MAX as u32) as u16;
}
RichInput::Motion { gyro, accel, .. } => {
self.state[idx].gyro = gyro;
self.state[idx].accel = accel;
}
}
self.write(idx);
}
fn write(&mut self, idx: usize) {
let st = self.state[idx];
if let Some(pad) = self.pads[idx].as_mut() {
pad.write_state(&st);
}
self.last_write[idx] = Instant::now();
}
/// Re-emit each live pad's current report if it's been silent for `max_gap` (the driver's timer
/// streams whatever's in the section, so this just keeps the section fresh / future-proofs parity
/// with the UHID backend's heartbeat).
pub fn heartbeat(&mut self, max_gap: Duration) {
let now = Instant::now();
for i in 0..self.pads.len() {
if self.pads[i].is_some() && now.duration_since(self.last_write[i]) >= max_gap {
self.write(i);
}
}
}
fn ensure(&mut self, idx: usize) {
if idx >= MAX_PADS || self.pads[idx].is_some() || self.broken {
return;
}
match DsWinPad::open(idx as u8) {
Ok(p) => {
tracing::info!(
index = idx,
"virtual DualSense created (Windows UMDF shm channel)"
);
self.pads[idx] = Some(p);
self.state[idx] = DsState::neutral();
self.last_rumble[idx] = (0, 0);
self.last_write[idx] = Instant::now();
}
Err(e) => {
tracing::error!(error = %format!("{e:#}"), "virtual DualSense creation failed — controller input disabled");
self.broken = true;
}
}
}
/// Service every pad: poll the section for a game's feedback. `rumble` fires `(index, low, high)`
/// only on change (universal 0xCA plane); `hidout` fires for each rich DualSense feedback event
/// (lightbar / player LEDs / adaptive triggers — 0xCD plane).
pub fn pump(
&mut self,
mut rumble: impl FnMut(u16, u16, u16),
mut hidout: impl FnMut(HidOutput),
) {
for i in 0..self.pads.len() {
let Some(pad) = self.pads[i].as_mut() else {
continue;
};
let fb = pad.service(i as u8);
if let Some(r) = fb.rumble {
if self.last_rumble[i] != r {
self.last_rumble[i] = r;
rumble(i as u16, r.0, r.1);
}
}
for h in fb.hidout {
hidout(h);
}
}
}
}