Logitech TrueForce Linux Driver

Warning This driver is under active development and may contain bugs or incomplete features. Use at your own risk. This disclaimer will be removed once the driver reaches a stable release.

New here with a wheel and a sim to race? Start with the step-by-step guide: docs/GETTING_STARTED.md

• from download to driving in about 15 minutes.

Linux kernel driver for Logitech TrueForce direct-drive racing wheels:

• Logitech RS50 (046d:c276)
• Logitech G PRO Racing Wheel for Xbox/PC (046d:c272)
• Logitech G PRO Racing Wheel for PS/PC (046d:c268)

Note: this project was previously named logitech-rs50-linux-driver. It was renamed 2026-07-02 because the driver covers the whole TrueForce direct-drive family, not just the RS50. Old GitHub links and clones redirect automatically. As of v0.12.0 the kernel module is hid-logitech-dd (previously the fork shipped as hid-logitech-hidpp and shadowed the in-tree driver); the installer migrates existing systems automatically.

You get the full evdev force-feedback suite (constant, spring, damper, friction, inertia, periodic, ramp, rumble, gain), all buttons, encoders, paddles, hat switch, 16-bit pedal axes, and G Hub-equivalent settings (rotation range, FFB strength / damping / TRUEFORCE / filter, pedal curves, LIGHTSYNC LEDs) exposed via sysfs. TrueForce haptics work in supported sims under Proton via Logitech's own signed SDK DLLs - see the recipe below.

This is a fork of the in-kernel hid-logitech-hidpp driver, scoped to only the Logitech direct-drive wheels - the RS50 and G PRO, across their three USB IDs (c276 RS50 native, c272 G PRO Xbox/PC which the RS50 also uses in compatibility mode, c268 G PRO PS/PC). It installs as a separate module, hid-logitech-dd, that binds only those wheels and runs alongside the in-tree hid-logitech-hidpp, which keeps handling all your other Logitech HID++ devices (mice, keyboards, G29 / G920 / G923 wheels, etc.) at its current, continuously-maintained version. No blacklist, no shadowing - this driver owns only the hardware it improves.

What works

Force feedback (full evdev suite, all routed to wheel torque): FF_CONSTANT, FF_SPRING, FF_DAMPER, FF_FRICTION, FF_INERTIA, FF_PERIODIC (sine, square, triangle, saw-up, saw-down), FF_RAMP, FF_RUMBLE, FF_GAIN. Verified with fftest, the in-tree tests/ff_matrix_test, and across multiple sims (ACC, AC, BeamNG, AMS2, Le Mans Ultimate, iRacing, Dirt Rally, ETS2).

Inputs: all buttons including the G1 (logo) button, both encoder rotaries with click, both shifter paddles, 8-direction D-pad as a hat switch, 16-bit wheel axis (up to 2700° on RS50), 16-bit pedal axes (throttle, brake, clutch). Button table further down.

G Hub-equivalent settings via sysfs at /sys/class/hidraw/hidrawX/device/wheel_*. Native mode (RS50 in its native 046d:c276 enumeration):

• Rotation range (90 to 2700°)
• FFB strength, damping, TRUEFORCE level, FFB filter (with auto)
• Sensitivity (desktop mode) and brake-force (onboard mode)
• Per-pedal response curves and deadzones, combined-pedals mode
• LIGHTSYNC LED slots, colors, effects, direction, brightness
• Mode + profile switching (desktop / onboard 1-5)
• Centre calibration (wheel_calibrate, wheel_calibrate_here)

Compat mode (RS50 or G PRO enumerated as 046d:c272 / 046d:c268) exposes a reduced HID++ feature set, but the same wheel-config attributes (range, strength, trueforce, damping, FFB filter, calibration, plus LIGHTSYNC) all work via fallback feature paths decoded from G Hub captures. The wheel boots in onboard mode in compat; write 0 to wheel_profile to enter desktop mode and have live SETs take effect on the motor. See "Compat-mode behavior" below for caveats.

TrueForce in Proton sims: end-to-end verified against Assetto Corsa Competizione and Assetto Corsa EVO - full FFB, TrueForce haptics, and complete button / paddle / encoder binding all working through Logitech's own signed SDK DLLs running unmodified under Proton. The same setup is expected to work for Le Mans Ultimate, AMS2, Assetto Corsa (the original 2014 game), rFactor 2, and iRacing - they all use the same SDK. The recipe below covers the setup. Our driver passes the SDK's raw writes through unchanged; no shim, no DLL injection.

Only ACC and AC EVO are verified; the rest are expected to work because they share the SDK, not confirmed. This project does not ship an rFactor 2 plugin: rFactor 2's TrueForce support is a separate third-party component (for example the community TF4ALL SimHub plugin), not something provided here, and it is untested with this setup.

See docs/SYSFS_API.md for the complete sysfs reference.

Compatibility matrix

What to expect per wheel. Legend: ✅ verified on hardware · 🟢 supported, expected to work (shares the verified code path, not yet tested on that exact model) · 🟡 implemented from captures, needs an owner to validate · - not applicable.

Capability	RS50 (c276 native / c272 compat)	G PRO Racing Wheel (c272 Xbox-PC / c268 PS-PC)
Steering, pedals, buttons, 8-way D-pad	✅	🟢
Force feedback (full evdev effect suite)	✅	🟢
TrueForce haptics (Proton + signed SDK)	✅	🟢
TrueForce texture routing for evdev effects (wheel_texture_route)	✅	🟢
Rotation range (90-2700°)	✅	🟢
FFB strength / damping / FFB filter (+ auto)	✅	🟢
TrueForce intensity / sensitivity / brake-force	✅	🟢
LIGHTSYNC RGB LEDs (RS50 faceplate strip)	✅	-
Rev-light level (wheel_rev_level, real G PRO rim)	-	🟡 needs a tester
Centre calibration	✅	🟢
Mode / profile switching	✅	🟢

The RS50 is the development hardware, so its column is verified directly in both native (046d:c276) and G PRO compatibility (046d:c272) modes, including SDK game TrueForce under Proton in each. A real G PRO runs the same hidpp_dd_ff_* code path as an RS50 in G PRO compatibility mode, so it is expected to work; we just do not have one to confirm against. G920 / G923 are handled by the in-tree hid-logitech-hidpp driver (this scoped fork no longer claims them); their standard HID++ FFB is unaffected, and the RS50/G-PRO-specific wheel_* settings do not apply to them. The G923 speaks the same TrueForce stream protocol as the DD wheels (confirmed on Windows by the TF4ALL project), and the udev rule now grants it hidraw access so the SDK DLLs can reach it under Proton - TrueForce on a G923 is plausible but unverified on Linux; testers wanted in issue #27.

Force-feedback effect types

All effects are routed to the wheel's single direct-drive motor (software-emulated on top of its constant-force endpoint), verified with fftest, the in-tree tests/ff_matrix_test, and in-game:

Effect	Notes
FF_CONSTANT	Direct torque (the steering/centring force).
FF_SPRING	Use this for auto-centring. Synthetic damping (wheel_spring_damping) keeps stiff springs stable on the direct-drive motor.
FF_DAMPER, FF_FRICTION, FF_INERTIA	Condition effects, sampled from live wheel motion.
FF_RAMP	Linear force ramp.
FF_PERIODIC	sine / square / triangle / saw-up / saw-down. 20 Hz and faster ride the TrueForce texture channel by default (wheel_texture_route).
FF_RUMBLE	Streams on the TrueForce texture channel by default, so it vibrates the rim without shaking the steering axis.
FF_GAIN	Global force scaling.
FF_AUTOCENTER	Driver-emulated damped centring spring (also via the autocenter sysfs); games can disable it per session as usual.

Verified game support

• Assetto Corsa Competizione and Assetto Corsa EVO - verified end-to-end under Proton: steering, full FFB, and TrueForce all at the same time, with PROTON_ENABLE_HIDRAW=1 and Steam Input disabled.
• Other Logitech-SDK sims (Le Mans Ultimate, AMS2, Assetto Corsa, rFactor 2, iRacing) share the same SDK and are expected to work; not yet confirmed.

Caveats:

• Some sims (AC EVO observed) reset the wheel's rotation range to 90° once at session start, via the game's own SDK path (a TrueForce operating-range packet, usbmon-verified). The driver detects this within 20 seconds and restores your range automatically (wheel_range_restore, default on, heavily safety-gated - see docs/SYSFS_API.md), logging both the external change and the restore in dmesg. Also check the game's own steering-rotation setting (AC EVO: "Steering lock") - once touched and re-applied, the game pushes its configured value itself. The in-game FFB gain is the master force control; wheel_strength is the wheel-side multiplier.
• AC EVO's map-load centring force has once been observed ringing the wheel into its over-torque failsafe (the base shuts itself off; power-cycle to recover). Instrumented sessions show AC EVO drives all its forces through the Logitech SDK stream rather than the kernel FFB path, so this is game/SDK-side behaviour; if it occurs, lower the in-game FFB gain or wheel_strength. Keep hands clear during map loads as a precaution.
• If a game stops seeing the wheel (dead bindings, hung map loads) after the driver was reloaded while Steam ran: restart Steam fully - its device list goes stale across driver reloads.

State of the driver

Verified on RS50 hardware (native and G PRO compatibility modes, plus extensive USB captures): everything checked in the matrix above, including full-lap ACC and AC EVO with simultaneous FFB and TrueForce.

Expected, needs a field report: a real G PRO (identical code path, issue #8) and the other Logitech-SDK sims (Le Mans Ultimate, AMS2, Assetto Corsa, rFactor 2, iRacing) - one confirmation each moves them into the verified column.

Not yet, vs G Hub on Windows: no GUI (settings are sysfs, partly Oversteer); two per-game Steam settings stay manual (PROTON_ENABLE_HIDRAW=1, Steam Input off); no firmware updates and no onboard-profile editing (slots select and read, not write).

Button Mapping

Buttons use sequential indices matching Windows DirectInput for cross-platform compatibility.

Index	Button
0	A
1	X
2	B
3	Y
4	Right Paddle / Gear Right
5	Left Paddle / Gear Left
6	RT (Right Trigger)
7	LT (Left Trigger)
8	Camera/View
9	Menu
10	RSB (Right Stick)
11	LSB (Left Stick)
21	Right Encoder CW
22	Right Encoder CCW
23	Right Encoder Push
24	Left Encoder CW
25	Left Encoder CCW
26	Left Encoder Push
27	G1 (Logitech logo)

D-pad reports as hat switch (ABS_HAT0X / ABS_HAT0Y).

Note: Indices 12-20 are gaps in the HID descriptor (unused).

Installation

This is the path most users want: from a fresh clone to a working wheel with full force feedback and (optionally) TrueForce in SDK-aware sims under Proton.

Short version - one command covers steps 1-5 below (DKMS build, migration off any old full-fork install, udev rule, module load, TrueForce shim if the SDK DLLs are staged), and doctor verifies every layer:

sudo ./tools/setup.sh        # install / update everything
./tools/setup.sh doctor      # health-check all layers, change nothing

The numbered steps below are what it does, kept for transparency and for anyone who prefers manual control.

Prefer a native package? Arch (AUR), Fedora/Nobara (COPR akmod), openSUSE (OBS), and Debian/Ubuntu (.deb from Releases) all have one, and they rebuild on kernel upgrades. See the distro table in Getting Started, step 1.

Atomic / immutable distros (Bazzite, Silverblue, Kinoite): DKMS does not work on rpm-ostree systems. Build the module as a static kmod in a toolbox and layer it with rpm-ostree install instead - see section 1a of the Getting Started guide.

Prerequisites

• Linux kernel 5.15 or newer (tested through 7.1)
• Kernel headers for the running kernel
• dkms, make, gcc or clang
• For TrueForce in Proton sims only: winegcc (ships with Wine on most distros), and a copy of Logitech G HUB on Windows from which to source four signed SDK DLLs. Skip these if you only want standard force feedback. You will still get full FFB (constant force, spring, damper, periodic, etc.) in every game.

There are no userspace components you need to compile by hand. The install script below handles the kernel module, the udev rule, and the SDK DLL installation into your wine prefixes.

Steps

1. Clone the repo.

   git clone https://github.com/mescon/logitech-trueforce-linux-driver.git
   cd logitech-trueforce-linux-driver

2. (TrueForce only) Stage the Logitech SDK DLLs. These are Logitech's own Authenticode-signed binaries. We do not redistribute them; you must supply your own copies from a Logitech G HUB installation on Windows (or G HUB unpacked into a throwaway wine prefix on Linux). Place exactly these four files at exactly these paths inside the repo:

   sdk/Logi/Trueforce/1_3_11/trueforce_sdk_x64.dll
   sdk/Logi/Trueforce/1_3_11/trueforce_sdk_x86.dll
   sdk/Logi/wheel_sdk/9_1_0/logi_steering_wheel_x64.dll
   sdk/Logi/wheel_sdk/9_1_0/logi_steering_wheel_x86.dll
   

   See sdk/README.md for more detail. If any are missing the SDK DLL install step in (3) prints a warning and is skipped; the kernel driver itself still installs fine.

3. Run the installer.

   sudo ./tools/dkms-update.sh

   This:

   • Registers the source under /usr/src/logitech-trueforce-1.0/ and runs dkms install so the kernel module rebuilds automatically on every kernel update.
   • Installs udev/70-logitech-trueforce.rules, which hands wheel_* sysfs and the wheel's hidraw nodes to your session user (no sudo needed for Oversteer or echo > wheel_*).
   • If winegcc is available and the SDK DLLs are staged (step 2), copies the four DLLs into every Steam wine prefix it finds and registers the two CLSIDs in each prefix's system.reg so SDK-aware sims (ACC, Le Mans Ultimate, AMS2, AC, rF2, iRacing) load TrueForce.

4. Reload the module and replug the wheel.

   No blacklist is needed: hid-logitech-dd claims only the three direct-drive wheels, which the in-tree drivers do not, so the two coexist without conflict.

   Safety: the RS50 can produce up to 8 Nm and may rotate under power. Hold the rim or keep clear whenever you load or reload the driver, replug the wheel, or switch profiles.

   sudo modprobe -r hid-logitech-dd 2>/dev/null
   sudo modprobe hid-logitech-dd

   Physically unplug then replug the wheel's USB cable (or reboot). dmesg | grep -i "force feedback" should show Force feedback initialized, prefixed with your wheel's model tag: RS50 (native):, RS50 (G PRO compatibility mode):, or G PRO:.

5. Smoke test.

   fftest /dev/input/by-id/*Logitech*event-joystick

   The wheel should respond to each effect in turn. fftest comes from the linuxconsoletools project: it's in the linuxconsole package on Arch-based distros (Arch, CachyOS, SteamOS) and linuxconsoletools on most others.

For ACC + TrueForce specifically, see "Recipe: SDK-aware sims (ACC, AC EVO, ...) on RS50 or G PRO" further down. Other SDK-aware sims follow the same recipe.

Updating after git pull

sudo ./tools/dkms-update.sh

Then reload as in step 4. A reboot is only needed on UEFI Secure Boot systems if the MOK key needs re-enrollment.

Adding TrueForce to a Wine prefix created later

For Steam games installed after step 3, or for non-Steam Wine prefixes (Heroic, Lutris, bottled wine):

./tools/install-tf-shim.sh --all-steam            # every Steam prefix
./tools/install-tf-shim.sh --prefix /path/to/pfx  # a single prefix

Run as your normal user, not sudo.

input group membership

Most desktop distros put interactive users in input automatically via systemd-logind uaccess. If echo > wheel_* returns EACCES:

sudo usermod -aG input "$USER"
# log out and back in

Build without DKMS (developers)

cd mainline
make
sudo rmmod hid-logitech-dd 2>/dev/null
sudo insmod ./hid-logitech-dd.ko

Recipe: SDK-aware sims (ACC, AC EVO, ...) on RS50 or G PRO

End-to-end verified against Assetto Corsa Competizione and Assetto Corsa EVO: full FFB, TrueForce haptics, and complete button / paddle / encoder binding, all delivered by Logitech's own signed SDK DLLs running unmodified under Proton. The same recipe is expected to work for the other Logitech-SDK-aware sims (Le Mans Ultimate, AMS2, Assetto Corsa, rFactor 2, iRacing). The recipe applies to both the RS50 and the G PRO Racing Wheel for Xbox/PC. Step 1 is RS50-only and optional.

1. (RS50, optional) You can switch the wheel into "G PRO compatibility" mode via the OLED menu (it reboots and reappears as 046d:c272), but as of 2026-07-08 this is not required: the SDK also accepts the RS50's native PID 046d:c276, verified end-to-end in AC EVO (usbmon-confirmed TrueForce stream). Native mode additionally unlocks the full 2700 range. Use compat mode only as a fallback if a specific game's SDK build does not recognise the native PID.
2. Set the wheel's steering angle. The default range can be very small (compat mode's factory default is 90°), much too small to drive with. Two equivalent paths:
   • From Linux (recommended): enter desktop mode and set the range live via sysfs:

     H=$(ls -d /sys/class/hidraw/*/device/wheel_range | head -1 | xargs dirname)
     echo 0   > "$H/wheel_profile"   # desktop mode
     echo 540 > "$H/wheel_range"     # 540 degrees lock-to-lock

   • From the OLED: edit the active onboard profile's stored steering angle. Each onboard profile carries its own.
3. Stage the four Logitech-signed SDK DLLs under sdk/Logi/ in the repo. We do not redistribute these; copy them out of a Logitech G HUB install on Windows (or G HUB unpacked into a throwaway wine prefix on Linux):

   sdk/Logi/Trueforce/1_3_11/trueforce_sdk_x64.dll
   sdk/Logi/Trueforce/1_3_11/trueforce_sdk_x86.dll
   sdk/Logi/wheel_sdk/9_1_0/logi_steering_wheel_x64.dll
   sdk/Logi/wheel_sdk/9_1_0/logi_steering_wheel_x86.dll
   

4. Install the DLLs into your Wine prefixes (idempotent, run as your normal user, not sudo):

   ./tools/install-tf-shim.sh --all-steam

5. Steam launch options: PROTON_ENABLE_HIDRAW=1 %command%. Required: the TF SDK only sees the wheel through hidraw nodes that Wine exposes when this is set.
6. In the game, Settings → Controls → load the "PRO Racing Wheel for Xbox/PC" preset (or the closest match), bind axes and buttons, then set the in-game Wheel Rotation / steering lock to match the angle you set in step 2. If a gamepad is plugged in, unplug or disable it during binding so the game's auto-bind does not pick it up over the wheel.

Other Logitech-SDK-aware sims (Le Mans Ultimate, AMS2, Assetto Corsa, rFactor 2, iRacing) follow the same recipe.

Compat-mode behavior

A few things look wrong but are firmware-side defaults that match Windows G Hub, not Linux bugs:

• The wheel self-centers when idle. The firmware applies its own centering spring whenever no game is driving FFB; a game (or the TF SDK) overrides it. No host command disables it.
• Factory steering angle is 90° in compat mode. Set it with wheel_profile=0 then wheel_range=<degrees>, or via the OLED. Some games (e.g. AC EVO) reset it to 90° on launch (firmware-side, not a range command from the game); if so, set the angle on the OLED after launch and pin the in-game range to match.
• wheel_profile=0 enters desktop mode, where live SETs to wheel_range, wheel_strength, wheel_trueforce, wheel_damping, and wheel_ffb_filter take effect immediately. Selecting onboard slots 1-5 via wheel_profile is unreliable in compat mode; use the OLED menu instead.
• wheel_brake_force, wheel_sensitivity, wheel_ffb_filter_auto return -EOPNOTSUPP on this firmware; configure via G Hub or the OLED.

Usage

Test Force Feedback

# Find your device
ls /dev/input/by-id/ | grep -i logi

# Test FFB (requires linuxconsole package)
fftest /dev/input/by-id/usb-Logitech_RS50*-event-joystick

Configure Settings via sysfs

Settings are exposed at /sys/class/hidraw/hidrawX/device/ (where X varies by system).

# Find your wheel's hidraw device
WHEEL_DEV=$(ls -d /sys/class/hidraw/*/device/wheel_range 2>/dev/null | head -1 | xargs dirname)
echo "Wheel found at: $WHEEL_DEV"

# Example: Set rotation to 900 degrees
echo 900 | sudo tee $WHEEL_DEV/wheel_range

# Example: Set FFB strength to 80%
echo 80 | sudo tee $WHEEL_DEV/wheel_strength

# Example: Set LED slot to CUSTOM 1 (slot 0)
echo 0 | sudo tee $WHEEL_DEV/wheel_led_slot

# Example: Set custom rainbow colors for all 10 LEDs (hex RGB triplets)
echo "ff0000 ff7f00 ffff00 00ff00 00ffff 0000ff 7f00ff ff00ff ff0080 ffffff" | sudo tee $WHEEL_DEV/wheel_led_colors
echo 1 | sudo tee $WHEEL_DEV/wheel_led_apply

Available sysfs Attributes

Mode and Profile:

Attribute	Range	Description
wheel_mode	desktop/onboard	Operating mode (Desktop or Onboard profiles)
wheel_profile	0-5	Active profile (0=Desktop, 1-5=Onboard profiles)

Force Feedback:

Attribute	Range	Description
wheel_range	90-2700	Rotation range in degrees
wheel_strength	0-100	FFB strength percentage
wheel_damping	0-100	Damping percentage
wheel_trueforce	0-100	TRUEFORCE audio-haptic level
wheel_sensitivity	0-100	Wheel sensitivity (Desktop mode only)
wheel_brake_force	0-100	Brake pedal load cell threshold (Onboard mode only)
wheel_ffb_filter	1-15	FFB smoothing level
wheel_ffb_filter_auto	0-1	Auto FFB filter (0=off, 1=on)
wheel_calibrate	0-65535 (write-only)	Raw encoder value to adopt as the new centre (RS50 and G Pro).

LIGHTSYNC LED Control:

Attribute	Range	Description
wheel_led_slot	0-4	Active custom slot (CUSTOM 1-5)
wheel_led_slot_name	string	Slot name (max 8 chars, stored on device)
wheel_led_slot_brightness	0-100	Per-slot brightness (applied when slot activated)
wheel_led_direction	0-3	Animation direction (0=L→R, 1=R→L, 2=In→Out, 3=Out→In)
wheel_led_colors	hex	10 space-separated RGB hex values (LED1-LED10)
wheel_led_effect	1-5	LED effect (1-4 = animated modes, 5 = static/custom slot colors)
wheel_led_brightness	0-100	Global LED brightness percentage
wheel_led_apply	(write)	Apply current slot config to device

Pedal Configuration:

Attribute	Range	Description
wheel_combined_pedals	0-1	Combined pedals mode
wheel_throttle_curve	0-2	Throttle response curve (0=linear, 1=low sens, 2=high sens)
wheel_brake_curve	0-2	Brake response curve
wheel_clutch_curve	0-2	Clutch response curve
wheel_throttle_deadzone	"L U"	Throttle deadzone (lower% upper%)
wheel_brake_deadzone	"L U"	Brake deadzone
wheel_clutch_deadzone	"L U"	Clutch deadzone

See docs/SYSFS_API.md for complete API documentation with examples.

Oversteer Compatibility

The driver exposes the standard new-lg4ff attribute set for Oversteer: range (to 2700°), gain, autocenter, spring_level/damper_level/friction_level, and combine_pedals, verified through Oversteer against a live wheel.

Full support needs a patch (oversteer-logitech-trueforce.patch, in this repo): it adds RS50 detection (046d:c276), the 2700° range, and finds the settings on the HID++ sibling interface (stock Oversteer looks on the joystick interface and only unlocks range for the G PRO, leaving the other controls greyed out). It applies cleanly to current Oversteer master; upstreaming is planned.

# pip / system install:
cd "$(python3 -c 'import oversteer,os; print(os.path.dirname(os.path.dirname(oversteer.__file__)))')"
sudo patch -p1 < /path/to/oversteer-logitech-trueforce.patch

# or from git source:
git clone https://github.com/berarma/oversteer.git && cd oversteer
git apply /path/to/oversteer-logitech-trueforce.patch && sudo pip install .

Flatpak Oversteer is sandboxed and can't be patched in place; install from source instead. Non-root access to the settings is handled by the driver's udev rule (installed by setup.sh).

Documentation

In-repo references for users and contributors:

• docs/SYSFS_API.md - every wheel_* sysfs attribute, with examples and per-mode availability (native vs. compat).
• docs/PROTOCOL_SPECIFICATION.md - HID++ feature catalog for both native and compat modes, the dedicated-endpoint FFB protocol, and the G PRO compat-mode feature decoding.
• docs/TRUEFORCE_PROTOCOL.md - interface-2 audio-haptic stream layout (init sequence, sample framing, gain/damping commands).
• sdk/README.md - inventory of Logitech's Windows SDK artifacts we reference, plus the DLL-staging layout consumed by tools/install-tf-shim.sh.

Userspace components

userspace/libtrueforce/ is a native-Linux C reimplementation of Logitech's TrueForce SDK. You do not need it for the ACC + TF recipe above - that path runs Logitech's own signed DLLs through Wine, which talk directly to our kernel driver. libtrueforce exists for native-Linux applications that want to drive TrueForce without going through Wine (for example a telemetry-driven haptic generator or a custom test rig). It has its own README and tests under userspace/libtrueforce/. Nothing in userspace/ is built or installed by the regular install flow.

Game compatibility

Games see the wheel as a standard Linux joystick with force feedback; no special setup beyond binding controls in-game. Verified titles are listed under Verified game support; TrueForce in SDK-aware sims needs the Proton recipe above. Some games want Steam Input enabled as a gamepad, or SDL_JOYSTICK_DEVICE=/dev/input/eventX.

Experimental inject_pid module parameter: for non-SDK games that use standard DirectInput PID force feedback (older/indie sims), the driver can inject a PID output collection on interface 0 and translate DInput FFB into evdev. Off by default (inject_pid=0); =1 dry-runs (logs only, no actuation), =2 actuates (bench-tested only). Unrelated to PROTON_ENABLE_HIDRAW, and not needed for any SDK-aware sim.

Technical details

The wheel is a 3-interface USB device: interface 0 = joystick input, interface 1 = HID++ 4.2 (config/settings), interface 2 = force-feedback output (64-byte reports on ep 0x03). Unlike the belt-driven G920/G923 (FFB over HID++ 0x8123, 900°), the direct-drive wheels use a dedicated FFB endpoint and reach 2700°, so the driver gates them on HIDPP_QUIRK_DD_FFB and initialises FFB on interface 1 only (interface 0 has no HID++). Full protocol in docs/PROTOCOL_SPECIFICATION.md.

Troubleshooting

"Invalid code 768" messages during boot

These come from the HID descriptor declaring more buttons than physically exist. This driver filters them (see hidpp_dd_input_mapping) so they never reach userspace - which means if you do see them, the wheel is being handled by hid-generic, not this driver. That happens when the wheel enumerates before the module loads. See "Wheel has no FFB / no wheel_* (stuck on hid-generic)" below.

Wheel has no FFB / no wheel_* (stuck on hid-generic)

If the wheel works as a plain joystick but has no force feedback and no wheel_* sysfs (and you see "Invalid code 768" in dmesg), hid-generic claimed it before this module was loaded. Fix it with:

sudo ./tools/rebind-wheel.sh

This loads the module and rebinds every wheel interface from hid-generic to this driver. If it reports the bind failed, the hid-logitech-dd module is not installed/loaded - run sudo ./tools/dkms-update.sh (then reload the module), and retry.

FFB not working

1. Verify the driver is bound to the wheel, not just loaded: ls /sys/class/hidraw/*/device/wheel_range should list a path. If it does not, see "stuck on hid-generic" above.
2. Check dmesg for errors: dmesg | grep -iE 'rs50|g pro'
3. Ensure you're testing with a game/app that supports FFB

FFB "pulls the wrong way" / wheel feels unstable under Wine/Proton

If a game amplifies your steering instead of pushing back toward centre (no self-centering when released), the FF_CONSTANT sign compensation is in the wrong state. Wine/Proton deliver FF_CONSTANT inverted relative to native evdev apps, so the driver inverts by default and Wine/Proton games feel right out of the box. Native-evdev tools (fftest, SDL FF, raw EVIOCSFF) then feel inverted - toggle it off:

WHEEL_DEV=$(dirname "$(ls -d /sys/class/hidraw/*/device/wheel_range | head -1)")
echo 1 | sudo tee "$WHEEL_DEV/wheel_ffb_constant_sign"   # invert (Wine/Proton, default)
echo 0 | sudo tee "$WHEEL_DEV/wheel_ffb_constant_sign"   # pass-through (native evdev)

Only FF_CONSTANT is affected. See docs/SYSFS_API.md.

Settings not persisting

sysfs settings are volatile and reset on driver reload. For persistent settings, add commands to a udev rule or startup script.

Wine/Proton: HIDRAW=0 vs HIDRAW=1

Wine's HID stack has two paths it can take for the wheel, and the right one depends on the game:

• PROTON_ENABLE_HIDRAW=0 (default): Wine routes the joystick interface via SDL. Suitable for native-Linux-style FFB games where no Logitech-specific SDK is involved - input flows cleanly and evdev FFB works through our driver.
• PROTON_ENABLE_HIDRAW=1: Wine exposes all wheel hidraw nodes to the Windows side. Required for any game that uses the Logitech TrueForce SDK (ACC, LMU, AMS2, AC, iRacing) - the SDK finds the wheel via Windows HID enumeration which only sees hidraw devices Wine has explicitly exposed.

If you see no FFB and the game's "wheel detection" or TrueForce check says no Logitech wheel is present, you probably need PROTON_ENABLE_HIDRAW=1 plus the steps in the SDK-aware-sims recipe above.

If the game just doesn't see any wheel at all (no FFB, ghost inputs), Wine may be holding the device through a different backend - the legacy fallback is to hide the wheel from Wine's hidraw layer entirely:

# Steam launch options:
PROTON_ENABLE_HIDRAW=0 %command%

# Or globally hide the wheel from any Wine prefix:
echo 'SUBSYSTEM=="hidraw", ATTRS{idVendor}=="046d", ATTRS{idProduct}=="c276", MODE="0000"' | \
  sudo tee /etc/udev/rules.d/99-hide-rs50-from-wine.rules
sudo udevadm control --reload-rules

Solution 2: Use SDL instead of Wine's dinput

Some games work better with SDL's joystick handling:

# Steam launch options:
SDL_JOYSTICK_HIDAPI=0 %command%

Solution 3: Check hidraw permissions

If Oversteer or sysfs settings don't work, Wine may have grabbed the hidraw device:

# Find your wheel's hidraw device number
ls -la /sys/class/hidraw/*/device/wheel_range 2>/dev/null

# Check who has the device open (replace X with your hidraw number)
sudo lsof /dev/hidrawX

# If wine processes are listed, close them or use Solution 1

Contributing

Contributions are welcome! There are several ways to help:

Code contributions: This driver is forked from JacKeTUs/hid-logitech-hidpp with RS50-specific additions. If your changes apply to other Logitech devices, please consider contributing upstream as well.

Testing: Try the driver and report issues. Include your kernel version, distribution, and any relevant dmesg output.

USB captures: If you own a Logitech wheel variant that isn't yet fully supported and want to help with reverse-engineering, open an issue and we will share the contributor capture tooling.

License

• Kernel driver (mainline/), tooling, and everything else: GPL-2.0-only (same as the Linux kernel it derives from). Full text in COPYING.
• libtrueforce (userspace/libtrueforce/): LGPL-2.1-or-later, so native Linux apps (including closed-source ones) may link it while changes to the library itself stay open. Full text in userspace/libtrueforce/COPYING.

Logitech's TrueForce SDK DLLs are not part of this project and are not redistributed here; users supply them from their own Logitech G HUB installation (see the Proton setup above).

Acknowledgments

• RS50 USB protocol reverse-engineered using Wireshark captures from G Hub on Windows
• Based on JacKeTUs/hid-logitech-hidpp which adds G Pro wheel support and improved FFB
• Upstream Linux kernel hid-logitech-hidpp driver by Benjamin Tissoires and contributors
• Oversteer by Bernat Arlandis for the wheel configuration GUI