Re: [GIT PULL] HID for 5.7

[Jiri Kosina <jikos@kernel.org>]

On Wed, 1 Apr 2020, Linus Torvalds wrote:

> > Samuel Čavoj (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