Re: [PATCH] HID: semitek: new driver for GK6X series keyboards

From: Jiri Kosina
Date: Wed May 05 2021 - 08:21:52 EST


On Sun, 7 Feb 2021, Benjamin Moody wrote:

> From: Benjamin Moody <bmoody@xxxxxxxxxxxxxx>
>
> A number of USB keyboards, using the Semitek firmware, are capable of
> handling arbitrary N-key rollover, but due to a buggy report
> descriptor, keys beyond the sixth cannot be detected by the generic
> HID driver.
>
> There are numerous hardware variants sold by several vendors, mostly
> using generic names like "GK61" for the 61-key version. These
> keyboards are sometimes known collectively as the "GK6X" series.
>
> The keyboard has three USB interfaces. Interface 0 uses the standard
> HID boot protocol, limited to eight modifier keys and six normal keys;
> interface 2 uses a custom report format that permits any number of
> keys. If more than six keys are pressed simultaneously, the first six
> are reported via interface 0 while subsequent keys are reported via
> interface 2.
>
> (Interface 1 uses a custom protocol for reprogramming the keyboard;
> this can be controlled through userspace tools and is not of concern
> for the present driver.)
>
> The report descriptor for interface 2, however, is incorrect (for
> report ID 0x04, the input field is marked as "array" rather than
> "variable".) The descriptor appears to be correct in other respects,
> so we simply replace the incorrect byte before parsing the descriptor.
>
> Signed-off-by: Benjamin Moody <bmoody@xxxxxxxxxxxxxx>

Applied, thanks.

--
Jiri Kosina
SUSE Labs