LegionI2CArrowLake

A codeless kext (one Info.plist, no binary) that lets VoodooI2C drive the I2C controllers of Intel's Arrow Lake-HX / 800-series PCH (8086:7F4C to 7F4F), so an I2C touchpad on those laptops works in macOS. VoodooI2C 2.9.1 only matches Sunrise Point, Cannon Lake, Comet Lake and Ice Lake controller IDs; this adds a personality for the Arrow Lake ones with the right timing values and the controller class that wakes the device from D3hot.

Written for a Lenovo Legion 5 15IAX10, whose ELAN06FA touchpad (PNP0C50, ACPI \_SB.PC02.I2C1.TPD0) sits on I2C1 = 8086:7F4D.

Status

What	Tested on	Result
Touchpad ELAN06FA on `8086:7F4D`	Legion 5 15IAX10, VoodooI2C 2.9.1 + VoodooI2CHID, macOS 15.8.1 and 26.7.1 (25G241), OpenCore 1.0.8	pointer, tap, two-finger scroll working daily since 2026-10-16; interrupt polled (`-vi2c-force-polling`), see below

What it can't do

It needs -vi2c-force-polling: VoodooGPIO has no community data for the Arrow Lake GPIO controllers (INTC1082 / INTC1084), so the touchpad interrupt cannot be routed and VoodooI2C polls instead. That costs a little CPU and latency; it does not affect how the pad feels here.
It only matches the controller. Your touchpad still needs the right VoodooI2C satellite (VoodooI2CHID for PNP0C50 HID-over-I2C devices) and an ACPI _STA that says the device is present under Darwin.
Tested on one laptop and one controller revision.

Installation

Install VoodooI2C 2.9.1 (with its VoodooGPIO and VoodooI2CServices plugins) and VoodooI2CHID the usual way. If VoodooPS2 is also loaded, load only one copy of VoodooInput.

Copy LegionI2CArrowLake.kext to EFI/OC/Kexts/ and add it to config.plist, Kernel > Add, after VoodooI2C and VoodooI2CHID:

BundlePath      LegionI2CArrowLake.kext
ExecutablePath  (empty)
PlistPath       Contents/Info.plist
MinKernel       (empty)
MaxKernel       (empty)
Enabled         true

Add -vi2c-force-polling to boot-args.

Reboot and check:

ioreg -r -c VoodooI2CPCILakeController -l -w0 | grep -E 'IOPCIMatch|I2CClkRate|COMP'
ioreg -r -c VoodooI2CHIDDevice | head

Rollback: set Enabled to false. It has no code, so the worst case is a touchpad that stays dead.

Properties

Key	Value	Where it comes from
`IOPCIMatch`	`0x7f4c8086&0xFFFCFFFF`	matches 7F4C, 7F4D, 7F4E, 7F4F
`IOClass`	`VoodooI2CPCILakeController`	the VoodooI2C controller class that forces the function to D0 through PMCSR before touching it
`I2CClkRate`	133000000	Linux `intel-lpss-pci.c`, `bxt_i2c_info` for these IDs
`I2CSdaHoldTimeNs`	42	same
`I2CSdaFallingTimeNs`	171	same
`I2CSclFallingTimeNs`	208	same
`IOProbeScore`	9999	above VoodooI2C's own personalities, which do not match anyway

How it works

VoodooI2C's controller personalities carry the clock and timing values per PCH generation and name a controller class. Linux gives the Arrow Lake-HX LPSS I2C functions the same bxt_i2c_info timing table as Ice Lake (0x34E8), so the Ice Lake values are copied. The first version used the plain VoodooI2CPCIController class and failed: the firmware leaves the controller in D3hot, every register read returned 0xffffffff (COMP_TYPE included), and VoodooI2C gave up. The VoodooI2CPCILakeController class writes the PMCSR (capability 0x80) to bring the function to D0 first, which is what 1.1.0 changed. More in docs/HOW-IT-WORKS.md.

Credits

VoodooI2C (alexandred and contributors, GPL-2.0): the driver this plugs into.
Linux drivers/mfd/intel-lpss-pci.c: the device IDs and timing table.

Licence

The Info.plist is ISC (see LICENSE). VoodooI2C itself is GPL-2.0 and is not included here.