Files
xone_macos/PLAN.md
T
portersky dae51f085b feat: pair controllers and show them in the app
Port the MT76 client functions (send_wlan, associate_client,
pair_client, set_client_key, remove_client) and wire the RX dispatch
into the session: EP IN frames are parsed, ASSOC_REQ associates a
controller (WCID plus chip programming), PAIR_REQ replies with
PAIR_RESP, and DISASSOC or client-lost removes it. The C API exposes
connected controllers and the app lists them by MAC. Bumps
xone_cli/xone_app to C++23: they were falling back to the default
standard once mt76.hpp started using std::span. Adds a unit test pinning
the WCID regions, the 32-byte rxwi, and the new frame control values.

Co-Authored-By: qwen3.8-27b@q2_k_xl: client functions, RX dispatch, GUI list
2026-08-29 13:36:32 +02:00

336 lines
15 KiB
Markdown

# Xbox Wireless Dongle — macOS Port
## Goal
User-space macOS app that speaks to the Xbox Wireless Dongle (MT76xx chip) and exposes connected controllers as HID gamepads.
## Architecture
```
┌──────────────────────────────────────────────────────┐
│ macOS App (Swift/C++) │
│ ┌──────────┐ ┌──────────┐ ┌──────────────────┐ │
│ │ App/UI │ │ HID Proxy│ │ Core Audio (opt) │ │
│ └────┬─────┘ └────▲─────┘ └──────────────────┘ │
│ │ │ │
│ ┌────▼──────────────▼──────────────────────┐ │
│ │ GIP Protocol Layer │ │
│ │ (bus/protocol.c — ported, pure C) │ │
│ └──────────────────┬───────────────────────┘ │
│ │ │
│ ┌──────────────────▼───────────────────────┐ │
│ │ MT76 Chip Protocol Layer │ │
│ │ (transport/mt76.c — ported, USB calls) │ │
│ └──────────────────┬───────────────────────┘ │
│ │ │
│ ┌──────────────────▼───────────────────────┐ │
│ │ USB Transport Layer (new) │ │
│ │ (IOKit / IOUSBInterfaceInterface) │ │
│ └──────────────────────────────────────────┘ │
│ │ │
│ ┌──────────────────▼───────────────────────┐ │
│ │ Xbox Wireless Dongle │ │
│ │ VID:045E PID:02FE (02E6, 02F9, 091E) │ │
│ └──────────────────────────────────────────┘ │
└──────────────────────────────────────────────────────┘
```
## Current Status
- Phase 1 (GIP + auth): ported and unit-tested.
- Phase 2 (USB transport): probe/open, async read pump, vendor requests,
bulk write. Verified on hardware.
- Phase 3 (MT76 chip): register/EFUSE access, firmware load (per-PID images),
radio init (registers, crystal, MAC/BSSID, channel eval, beacon). Verified
end-to-end: `radio-init` completes, beacon TX enabled, FCE shows firmware
running.
- C API + Swift app: async session (fast probe; firmware + radio on a worker
thread), state display (idle/starting/ready/error).
Remaining for Phase 3: controller association and the data path (design below).
Then Phase 4 (HID) and Phase 5 (app polish).
**Immediate goal:** pair a controller and show it in the GUI. Exposing it as
a macOS HID device is deferred.
## Directory Layout
```
macos/
├── PLAN.md ← this file
├── src/
│ ├── usb/ ← IOKit USB transport (new)
│ ├── mt76/ ← MT76 chip protocol (port from transport/mt76.c)
│ ├── gip/ ← GIP protocol (port from bus/protocol.c)
│ ├── auth/ ← Auth + crypto (port from auth/)
│ ├── hid/ ← Virtual HID gamepad (new)
│ └── app/ ← macOS app entry point + UI (new)
├── include/
│ ├── common/ ← Shared types, platform abstraction
│ ├── usb/
│ ├── mt76/
│ ├── gip/
│ ├── auth/
│ └── hid/
├── scripts/
│ └── download-firmware.sh ← Port of install/firmware.sh
├── firmware/ ← Downloaded firmware binaries (gitignored)
└── build/ ← Build output (gitignored)
```
## Implementation Phases
### Phase 1 — Foundation (Linux → C library)
Extract the protocol logic from Linux kernel code into standalone C.
**src/gip/**
- Port `bus/protocol.c` → pure C, no kernel deps
- Redefine `__le16`, `__packed`, `guid_t` for user-space
- Replace `kzalloc`/`kfree``malloc`/`free`
- Replace `spin_lock_irqsave` → pthread mutex or lock-free ring buffer
- Replace `dev_dbg`/`gip_err` → NSLog or custom logger
- Replace `EXPORT_SYMBOL_GPL` → nothing (static library)
**src/auth/**
- Port `auth/auth.c` + `auth/crypto.c` → AES-CCMP, authentication handshake
- Should be mostly copy-paste, these are pure crypto
**include/common/**
- Platform types (`stdint.h` based)
- Endianness helpers
- Memory allocator abstraction (so we can swap malloc if needed)
### Phase 2 — USB Transport (new)
**src/usb/**
- IOKit device matching on `USB\VID_045E&PID_02FE` (and other PIDs)
- Open device, claim interface (bInterfaceNumber = 1)
- `IOUSBDevInterface` for control transfers (vendor requests)
- `IOUSBInterfaceInterface` for bulk endpoints:
- EP 0x04 IN — WLAN data (802.11 frames from controllers)
- EP 0x04 OUT — Bulk out (commands to chip)
- EP 0x05 IN — MCU commands (firmware load responses)
- Async completion callbacks → callback/dispatch queue
- Device disconnect handling (chip reconnects during firmware load)
**Key IOKit APIs:**
- `IOServiceMatching("IOUSBDevice")` — find dongle
- `IOUSBDeviceOpen` / `IOUSBInterfaceOpen` — claim
- `DeviceRequest` — control transfers (register R/W)
- `WritePipe` / `ReadPipe` — bulk transfers
- `CreateInterruptEndpoint` — for EP 0x05 (MCU)
### Phase 3 — MT76 Chip Protocol (port)
**src/mt76/**
- Port `transport/mt76.c` → replace USB calls with Phase 2 transport
- **Firmware loading:** send binary in 0x3800-byte chunks, poll for completion
- **EFUSE read:** MAC address, chip ID, crystal trim, TX power calibration
- **Radio init:** ~80 hardcoded register writes (AGC, EDCA, TX power, protection)
- **Channel evaluation:** cycle through 12 channels, pick highest power
- **Beacon transmission:** 802.11 beacons with Microsoft OUI IE
- **Pairing mode:** rotate channels every 2s when pairing enabled
- **Controller association:** 802.11 assoc, WCID assignment, AES-CCMP encryption
- **Data path:** QoS data frames to/from controllers
**Key replacement map:**
- `usb_control_msg()``IOUSBDevInterface->DeviceRequest()`
- `usb_bulk_msg()``IOUSBInterfaceInterface->WritePipe()` / `ReadPipe()`
- `kzalloc`/`skb_put``malloc`/buffer management
- `msleep`/`mdelay``usleep`/`nanosleep`
- `ieee80211_*` → custom 802.11 frame builders
- `cfg80211_*` → nothing (no regulatory domain reporting needed)
### Phase 4 — Virtual HID Gamepad (new)
**src/hid/**
- Expose controller as macOS HID device so games work natively
- Options:
- **HID Proxy Driver (DriverKit)** — Maps USB device to virtual HID. Minimal kernel code. Preferred approach.
- **IOHIDSystem user-space** — Create virtual HID device entirely in user-space. May not work for all games.
- **Gamepad wrapper** — Lower-level, translate input events to HID reports.
- Map Xbox controller buttons/sticks/triggers to standard Xbox 360/One HID report descriptor
- Handle force feedback (rumble) — send back to dongle via GIP
- Battery status reporting
### Phase 5 — macOS App (new)
**src/app/**
- Swift or C++ main app
- Device discovery (IOKit notification when dongle plugged in)
- Pairing UI (LED blink, controller button press)
- Status display (connected controllers, battery)
- Preferences (channel selection, LED mode)
- Menubar icon for status
- Firmware download helper (script or in-app)
## Controller Association Design
Ported from `transport/dongle.c` and `transport/mt76.c`. Goal: pair a
controller and show it in the GUI. Exposing it as a macOS HID device is
deferred.
### RX Path
Both EP IN endpoints (0x04 WLAN, 0x05 CMD) feed one handler:
1. `process_buffer`: take the raw IN buffer.
2. `process_message`: parse the u32 info header; read D_PORT. Ignore command
responses (CMD_SEQ == 0x01). Strip header + 4-byte trailer.
- D_PORT == WLAN: go to step 3.
- D_PORT == CPU_RX: dispatch by EVT_TYPE:
- BUTTON (0x04): enter pairing mode.
- PACKET_RX (0x0c): go to step 3 (payload is a WLAN frame).
- CLIENT_LOST (0x0e): payload[0] = wcid; remove that client.
3. `process_wlan`: parse rxwi (16 bytes); if RXINFO_L2PAD set, skip the
2-byte pad after the 802.11 header; trim to MPDU_LEN from rxwi.ctl.
4. `process_frame`: dispatch by frame_control:
- DATA|QOS_DATA: feed the client's GIP adapter (`gip_process_buffer`).
- MGMT|ASSOC_REQ: add a client (addr2 = controller MAC).
- MGMT|DISASSOC: remove client (wcid from rxwi.ctl).
- MGMT|0x70 (WLAN_RESERVED): client command; payload[1] is PAIR_REQ (0x01)
or ENABLE_ENCRYPTION (0x10).
### Client Lifecycle
- create_client: find a free WCID (1..16); create a GIP adapter for it.
- associate_client(wcid, mac): `write_burst(WCID_ADDR, mac)`; ms_command(
ADD_CLIENT, {wcid-1,0,0,0,0x40,0x1f,0,0}); send an ASSOC_RESP mgmt frame via
`send_wlan` (fc = MGMT|ASSOC_RESP, da/sa/bssid, status_code = 0x0110,
aid = 0x0f00).
- pair_client(mac): send a PAIR_RESP mgmt frame via `send_wlan`
(fc = MGMT|0x70, reserved + PAIR_RESP byte + 9-byte payload).
- remove_client(wcid): ms_command(REMOVE_CLIENT, {wcid-1,0,0,0}); zero the
WCID ADDR/IV/ATTR regions.
- LED: on when a client is added outside pairing mode; off when the last
client leaves.
### Architecture
One GIP adapter per controller, keyed by the chip's WCID (matches upstream).
The rxwi.wcid identifies which controller a frame belongs to; within each
adapter the GIP client ID is 0. Our ported `get_client` auto-creates a client
on first packet, so a fresh adapter yields its single client on demand.
(Verify the GIP header client ID on hardware.)
### Constants To Add (mt76_defs.hpp)
- WCID regions: ADDR base 0x1800 (+n*8), KEY base 0x8000 (+n*32, len 16),
IV base 0xa000 (+n*8), ATTR base 0xa800 (+n*4); ATTR pairwise bit 0,
pkey mode genmask(3,1) = AES_CCMP (4).
- TXD info: DPORT genmask(29,27), QSEL genmask(26,25) EDCA=2, WIV bit 24,
80211 bit 19.
- RX FCE info: CMD_SEQ genmask(19,16), EVT_TYPE genmask(23,20), D_PORT
genmask(29,27).
- rxwi: RXINFO_L2PAD bit 14; CTL_WCID genmask(7,0); CTL_MPDU_LEN genmask(29,16).
- Events: BUTTON 0x04, PACKET_RX 0x0c, CLIENT_LOST 0x0e.
- Client commands: WLAN_RESERVED fc 0x70; PAIR_REQ 0x01, PAIR_RESP 0x02,
ENABLE_ENCRYPTION 0x10.
- 802.11 FCTL: MGMT 0x00, DATA 0x08; ASSOC_REQ 0x00, ASSOC_RESP 0x10,
DISASSOC 0xa0, QOS_DATA 0x70.
### chip Functions To Port (mt76.c)
`send_wlan`, `associate_client`, `pair_client`, `send_client_command`,
`set_client_key`, `remove_client`.
### GUI
- C API: expose connected controllers (count + per-client info: MAC, product
name from GIP identify, battery).
- Swift app: list controllers in the Controllers section of the Debug view.
## Dongle Initialization Sequence
```
1. Detect dongle via IOKit
2. Download/verify firmware (firmware.sh)
3. Load firmware into chip (bulk transfer, 0x3800 byte chunks)
4. Chip disconnects + reconnects (handle this!)
5. Read EFUSE (MAC, chip ID, TX power cal)
6. Initialize radio (~80 register writes)
7. Evaluate channels (find best channel)
8. Start beacon transmission
9. Enter pairing mode (channel rotation)
10. When controller associates:
a. Parse 802.11 assoc request
b. Assign WCID (client ID)
c. Set up AES-CCMP encryption
d. Send assoc response
11. GIP handshake:
a. Controller ANNOUNCE (vendor/product/fw version)
b. Host sends IDENTIFY request
c. Controller sends IDENTIFY (capabilities, interfaces, HID descriptor)
d. Auth handshake (AES-CCMP key exchange)
e. Status reports begin (battery, connected)
12. Game loop:
a. Controller → HID reports (input)
b. Host → rumble, LED, audio control
```
## Firmware
Firmware binaries are downloaded from Microsoft Windows Update driver catalog:
| PID | Dongle Type | Firmware File |
| ---- | ---------------------- | -------------------- |
| 02E6 | Old dongle | xone_dongle_02e6.bin |
| 02FE | New dongle | xone_dongle_02fe.bin |
| 02F9 | Built-in (ASUS/Lenovo) | xone_dongle_02f9.bin |
| 091E | Surface Book 2 | xone_dongle_091e.bin |
Downloaded via `scripts/download-firmware.sh` (port of `install/firmware.sh`).
## Known Challenges
1. **USB timing** — MT76 is timing-sensitive. User-space USB on macOS may have different latency than Linux kernel URBs. May need careful tuning of `usleep` values.
2. **Chip reconnect** — During firmware load, the dongle disconnects and reconnects. IOKit needs to handle this gracefully (close, wait, reopen, re-claim).
3. **Virtual HID** — Games expect a real HID device. HID Proxy Driver (DriverKit) is the cleanest path but requires a minimal kernel extension.
4. **5GHz regulatory** — The dongle uses 5GHz channels. macOS may have regulatory restrictions. May need to limit to 2.4GHz only.
5. **Audio** — Headset audio is complex (real-time PCM streaming). Lower priority, tackle after gamepad works.
## Source Files to Port
| Linux source | Target | Notes |
| ----------------------- | -------------------------- | ---------------------------------- |
| `transport/mt76.c` | `src/mt76/mt76.c` | Replace USB calls, remove cfg80211 |
| `transport/mt76.h` | `include/mt76/mt76.hpp` | Clean up kernel types |
| `transport/mt76_defs.h` | `include/mt76/mt76_defs.hpp` | Mostly copy (register defs) |
| `bus/protocol.c` | `src/gip/protocol.c` | Replace kernel alloc/lock/debug |
| `bus/protocol.h` | `include/gip/protocol.hpp` | Clean up kernel types |
| `bus/bus.c` | `src/gip/bus.c` | Client lifecycle management |
| `auth/auth.c` | `src/auth/auth.c` | Pure crypto, mostly copy |
| `auth/auth.h` | `include/auth/auth.hpp` | Copy |
| `auth/crypto.c` | `src/auth/crypto.cpp` | AES-CCMP, mostly copy |
| `auth/crypto.h` | `include/auth/crypto.hpp` | Copy |
| `driver/gamepad.c` | N/A | Replaced by HID layer |
## Build System
- **CMake** or **Xcode project** — either works
- Static library for protocol/auth layers
- macOS app bundle for the final product
- Minimum macOS: 12.0 (Monterey) — for modern IOKit/DriverKit support
## Dependencies
- IOKit (system)
- CoreFoundation (system)
- HID Proxy Driver framework (optional, for virtual gamepad)
- Core Audio (optional, for headset support)
- No external dependencies for protocol/auth layers