[Bug 289353] [ig4] touchpad broken on MateBook X Pro 2023 with 15.0-CURRENT

https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=289353

--- Comment #1 from huanghwh@gmail.com ---
The culprit is "iichid: Stop using split I²C bus transactions" by git bisect:

commit 36027361f9cfb76013153a032286eccda1512359 (HEAD)
Author: Poul-Henning Kamp <phk@FreeBSD.org>
Date:   Tue Jul 29 06:17:43 2025 +0000

    iichid: Stop using split I²C bus transactions

    Read IIC-HID reports as a single I²C transaction, instead of reading
    first the two byte length field, holding the bus, and then the rest
    of the report in a separate transaction.

    While technically legal, I²C bus split transactions are not universally
    supported, and in particular the "Snapdragon Elite" ARM CPU does
    not seem to support them.

    It is also not obvious that they are beneficial in this case, given
    the overhead of controller setup, interrupts and tear-down.

    Reviewed by: wulf
    Differential Revision: https://reviews.freebsd.org/D51302

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