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Date:   Wed, 9 Nov 2022 22:14:36 +0100
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Subject: Re: [Regression] Cambridge Silicon Radio, Ltd Bluetooth Dongle
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To:     Luiz Augusto von Dentz <luiz.dentz@gmail.com>,
        Jack <ostroffjh@users.sourceforge.net>
Cc:     linux-bluetooth@vger.kernel.org,
        Paul Menzel <pmenzel@molgen.mpg.de>,
        Marcel Holtmann <marcel@holtmann.org>,
        Hans de Goede <hdegoede@redhat.com>
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 <CABBYNZKDEjYOW+b1snUsvBgidW37+tPbsidq0pXaOqWKvRC8uQ@mail.gmail.com>
From:   Swyter <swyterzone@gmail.com>
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>> In case it helps any, I have applied Swyter's patch referenced at
>> comment #243 of the bug referenced above, and it does restore function
>> to my particular dongle (Gentoo linux, with gentoo-sources kernel
>> 6.0.6.)  (I believe I provided the git bisect quoted at the top of this
>> message.)
>
> Ive applied the first 2 patches, the third one I'm not so sure I'd
> like to introduce another module parameter.

Thanks for that, Luiz. The module parameter does help a lot and it
has been requested a few times in the Bugzilla thread.

I have been thinking about this problem for a long time.

Essentially nulls-out any potential drawback the suspend workaround
may ever cause. In the past for this we used a very spotty whitelist,
but we can't really work with that here. When I'm talking about hundreds
to thousands of dongles in various states of brokenness I mean it.

The generic catch-all-as-best-as-we-can is the best way forward here.

Detecting fakes is hard enough, detecting dongles that don't like
the suspend workaround is essentially impossible. As they all
share the same identifiers than the ones that do.

Some fakes NEED the suspend workaround to work at all while a *much*
smaller subset of otherwise identical dongles have trouble with it.

Thanks to this last-effort parameter we can cover that last mile
without people having to recompile custom versions of btusb.

My dongle doesn't work? Easy, add this here. Most people won't
have to bother with this, but that final ~3% would be screwed.