Comment 414 for bug 1887190

On Mon, Apr 05, 2021 at 03:22:24PM -0000, James Hennig wrote:
>Since this is the main thread on the Internet about this issue, I
>suppose it is appropriate to post here even though I am using Manjaro.
>
>- This issue is non-present on a Thinkpad 3 14ADA05 with touchpad
>MSFT0001:00 06CB:CE2D on kernel 5.9.16-1 which uses i2c_hid. It is not
>elantech or designware (doesn't load the associated specific i2c
>drivers). Installing an entirely new keyboard panel with a new touchpad,
>essentially rebuilding the entire laptop does not address this issue. It
>is the same model touchpad for this specific laptop model even if you
>order a new one (unless I got bad luck of the draw).

If kernel 5.9.16-1 with i2c_hid driver worked for you, I'd suggest you
stick with the i2c_hid that comes with kernel 5.9.16-1 and build a
stand-alone driver for newer kernel and replace newer i2c_hid driver.

>
>- The issue becomes present on kernel 5.10.23-1 (and previous versions
>of 5.10) up to 5.12rc3. Have not tried compiling 5.12rc5, but no reason
>to believe it would work.
>
>The touchpad will fail to be recognized and work on bootup between 1-30
>reboots. I have tried many things such as different kernels and
>GRUB_CMDLINE_LINUX_DEFAULT options, yes even checking to set the kernel
>config option others are suggesting (Manjaro removed then reinstated the
>CONFIG_I2C_HID_ACPI=m option). I also tore apart kernels 5.9 and 5.10 to
>look at the pinctrl-amd.c driver and found that there was no difference
>between the two on these kernels, so it is something other than what
>https://launchpadlibrarian.net/500948605/0303-pinctrl-amd2.patch
>addresses since it works on the former kernel but not the latter. Also,
>the patch fails to apply on 5.12rc5.
>
>I don't really know how to compare the entire torn-apart kernels 5.9 and
>5.10 to try and find what change(s) could possibly cause this bug.
>Hopefully someone else knows how to?
>
>Might be able to get somewhere if so...
>
>Other mods might be replacing the touchpad with a model not designed for
>the laptop, but I don't know where to start with that either.
>