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Date:   Mon, 3 Jul 2023 11:36:20 +0100
From:   Daniel Thompson <daniel.thompson@linaro.org>
To:     Julius Zint <julius@zint.sh>
Cc:     Lee Jones <lee@kernel.org>, Jingoo Han <jingoohan1@gmail.com>,
        Helge Deller <deller@gmx.de>, linux-kernel@vger.kernel.org,
        dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org
Subject: Re: [PATCH 0/1] Backlight driver for the Apple Studio Display
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References: <20230701120806.11812-1-julius@zint.sh>
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On Sat, Jul 01, 2023 at 02:08:02PM +0200, Julius Zint wrote:
> I have been using and testing this as a DKMS for 6 months now without
> any known issues. It bothers me, that it needs to be part of the
> initramfs instead of just working out of the box. Maybe someone else
> here knows, how to tell the USB HID driver, that this is not a HID device
> and it should keep its fingers from it.

If is says it is a HID device and is uses HID reports for control then
it *is* a HID device!

In other words you need your driver to register as a HID driver instead
of sending raw HID frames using the USB stack. If you do that then the
HID core infrastructure will ensure the right driver gets loaded (it
has special logic to automatically unregister hid-generic and load the
better driver as soon as one becomes available).


Daniel.