Re: [GIT PULL] HID for 5.7

From: Jiri Kosina
Date: Fri Apr 03 2020 - 06:05:45 EST


On Wed, 1 Apr 2020, Linus Torvalds wrote:

> > Samuel Äavoj (1):
> > HID: Add driver fixing Glorious PC Gaming Race mouse report descriptor
>
> What a glorious name for a piece of hardware. Even if it's apparently
> buggy and needs help to work right.

Yeah, the vendor apparently was not of the humble kind :)

> I felt bad saying I don't need that glorious driver when doing my
> oldconfig.

:))

> Anyway, because I noticed this due to the name, it does strike me that
> clearly Windows must be ignoring - or otherwise reacting differently to
> - the HID_MAIN_ITEM_CONSTANT flag. Because presumably those mice work
> under Windows without special drivers?
>
> In fact, reading that driver, it looks like they report being *both*
> constant *and* variable in their report descriptors. Which sounds odd.
> Maybe we should do whatever Windows does, and not need a special driver
> for this maybe-bot-so-glorious-after-all mouse hardware?

Adding Samuel to CC.

>From what I understood is that in order to access the buttons reported in
report #2 (the one marked with HID_MAIN_ITEM_CONSTANT), you actually *do*
need a special software on windows anyway.

What we do is that we ignore any changes in reports with
HID_MAIN_ITEM_CONSTANT in the HID core.

It would still be possible to access the report via hidraw, and maybe
that's analogy of what the Windows driver/special Glorious software :)
does, I don't know. It's hard to believe that Windows would be actually
willing to report any changes coming through HID_MAIN_ITEM_CONSTANT
reports, but who knows.

--
Jiri Kosina
SUSE Labs