Re: [BUG] HID: i2c-hid: ELAN 04F3:30FD touchpad reset race causes -EREMOTEIO on HP Pavilion Gaming 15-ec1xxx

One more data point, in case it's useful.

I also tried a fresh openSUSE Tumbleweed live/install on the same
hardware. On one boot the touchpad did start working - dmesg from that
boot is attached as dmesg-opensuse-working.txt. A few things that stood
out:

- The initial HID descriptor fetch succeeded quickly (~2.3s in), unlike
  the usual Arch failure.
- Registration (hid-generic, then hid-multitouch) proceeded normally.
- Every subsequent get/set report transaction still failed with -121
  for roughly 35-38 seconds after that (including one "device returned
  incorrect report (2 vs 6 expected)"), before apparently
  self-resolving - no further errors after that point, and the
  touchpad was usable.

I then rebooted the same openSUSE several more times and got
the usual non-working result again, so this doesn't seem to be
something openSUSE fixes - just the same intermittent race showing up
there too. It does suggest the issue may not be limited to the very
first reset/descriptor-fetch step - there may be an ongoing i2c bus
communication problem for a while after boot that intermittently
self-resolves, rather than a single narrow timing window right at
probe.

Happy to keep gathering data if useful.

Thanks,
Adam

On Sun, Aug 16, 2026 at 7:52 PM Adam <[email protected]> wrote:

> Thanks for looking into this.
>
> Attached:
> - dmesg-failing-boot.txt - full dmesg from a failing boot, with
>   i2c_hid.dyndbg=+p and i2c_hid_acpi.dyndbg=+p set on the kernel command
>   line from the start, on the unpatched linux kernel (7.1.8-arch1-3).
> - acpidump-output.txt - full acpidump output from the same machine.
>
> Unfortunately I wasn't able to capture a successful boot for comparison
> despite several attempts - in my experience the touchpad only initializes
> successfully very rarely (I estimated roughly 1 in 10-15 boots when I was
> testing before, but going by the last few days of retries it seems to be
> even less frequent than that, maybe closer to 1 in 30+). I'm happy to keep
> retrying over the coming days and send a successful-boot log if/when I
> get one, if that's still useful.
>
> Let me know if there's anything else that would help.
>
> Thanks,
> Adam
>
> On Sat, Aug 15, 2026 at 9:33 PM Lovekesh Solanki <
> [email protected]> wrote:
>
>> On Mon, Aug 10, 2026 at 07:31:32PM +0200, Adam wrote:
>> > Hello,
>> >
>> > I'm reporting a reproducible probe failure for an ELAN i2c-hid touchpad
>> > (ACPI ELAN0718:00, VID:PID 04F3:30FD) on an HP Pavilion Gaming
>> 15-ec1033nw
>> > (AMD platform, i2c bus under AMDI0010:03). The touchpad fails to
>> > initialize on nearly every boot on Linux, while the same hardware works
>> > reliably every time under Windows 11 on the same machine (dual context,
>> > same BIOS F.35 rev.A).
>> >
>> > Kernel: 7.1.6-arch1-1 (Arch Linux)
>> > Also reported by other users with the same touchpad ID on different
>> > kernels/distros (Arch, Ubuntu, Linux Mint) going back to at least 2022:
>> > - https://bbs.archlinux.org/viewtopic.php?id=277393
>> > - https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2031061
>> > - https://forums.linuxmint.com/viewtopic.php?t=329212
>> >
>> > Symptom (default logging):
>> >
>> >   i2c_hid_acpi i2c-ELAN0718:00: failed to fetch HID descriptor: -121
>> >   i2c_hid_acpi i2c-ELAN0718:00: Failed to fetch the HID Descriptor
>> >   i2c_hid_acpi i2c-ELAN0718:00: probe with driver i2c_hid_acpi failed
>> with
>> > error -121
>> >
>> > With dynamic_debug enabled for i2c_hid and i2c_hid_acpi:
>> >
>> >   i2c_hid_start_hwreset
>> >   i2c_hid_set_power: cmd=05 00 00 08
>> >   i2c_hid_xfer: cmd=05 00 00 01
>> >   i2c_hid_finish_hwreset: waiting...
>> >   i2c_hid_finish_hwreset: finished.
>> >   asking HID report descriptor
>> >   i2c_hid_xfer: cmd=02 00
>> >   reading report descriptor failed
>> >   can't add hid device: -121
>> >   probe with driver i2c_hid_acpi failed with error -121
>>
>> Could you attach full dmesg with debug enabled, of failing boot and
>> successfull boot? And also acpidump?
>>
>> Thanks,
>> Lovekesh
>>
>