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Date:   Fri, 13 May 2022 00:47:49 +0200
From:   Dmitry Torokhov <dmitry.torokhov@gmail.com>
To:     Pablo Ceballos <pceballos@google.com>
Cc:     Jiri Kosina <jikos@kernel.org>,
        Benjamin Tissoires <benjamin.tissoires@redhat.com>,
        lkml <linux-kernel@vger.kernel.org>,
        "linux-input@vger.kernel.org" <linux-input@vger.kernel.org>
Subject: Re: [PATCH] HID: Driver for Google Hangouts Meet Speakermic
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On Thu, May 12, 2022 at 03:35:00PM -0700, Pablo Ceballos wrote:
> On Thu, May 12, 2022 at 3:53 AM Jiri Kosina <jikos@kernel.org> wrote:
> > On Thu, 12 May 2022, Dmitry Torokhov wrote:
> > > I am curious, could not this be achieved without a kernel driver by
> > > simply using udev to map this usage code to KEY_RESERVED?
> >
> > Hmm, good point, using KEY_RESERVED mapping to achieve the key being
> > actually ignored didn't immediately occur to me.
> >
> > Pablo, could you please verify that it behaves in the expected way, and
> > confirm that we could drop the 'driver' in favor of udev rule?
> 
> I think I've achieved the same result by adding the following to udev
> hwdb. Dmitry, is this what you had in mind, or is there a better way
> of doing this?
> 
> evdev:input:b0003v18D1p8001*
>  KEYBOARD_KEY_b002f=reserved

No, that is exactly what I had in mind, thank you. Please submit this
entry to upstream systemd/udev project (and we can cherry-pick it into
our udev as well).

In general I think we should try to avoid trivial "fixup" HID drivers if
it is possible. I also wondered if we could be supplying fixed-up HID
descriptors via request_firmware() for HID devices.

Thanks.

-- 
Dmitry