Re: PROBLEM: Regression likely in hid_uclogic driver breaks Huion Inspiroy H640 drawing tablet

From: José Expósito
Date: Thu Aug 04 2022 - 14:24:58 EST


Hi again,

On 2022-07-26 18:48, José Expósito wrote:
> The first bad commit is 87562fcd1342 ("HID: input: remove the need for
> HID_QUIRK_INVERT"):
> https://lore.kernel.org/all/20220203143226.4023622-11-benjamin.tissoires@xxxxxxxxxx/
> (CCing the folks whose email is in the patch tags)
>
> I reverted the patch on hid/for-next and, after fixing a tiny conflict,
> I can confirm that the tablet works again as expected.
>
> I'd need to investigate a bit more over the weekend, but I think that
> all HUION tablets with the latest firmware (internally, v2) are
> affected.

Indeed, it looks like v2 devices are affected. Similar reports:

- https://github.com/DIGImend/digimend-kernel-drivers/issues/626
- https://bugzilla.kernel.org/show_bug.cgi?id=216106

Kindly sending this thread back to your inbox to see if we could fix
this regression.

Best wishes,
Jose

> Those tablets do not set the inrange bit (UCLOGIC_PARAMS_PEN_INRANGE_NONE).
> The driver sets it and uses a timer to remove it.
> See drivers/hid/hid-uclogic-core.c, function uclogic_raw_event_pen().
> [...]