bug#35574: bcm5974 touchpad is not recognized as touchpad

["pelzflorian (Florian Pelz)" <pelzflorian@pelzflorian.de>]

On Mon, Apr 20, 2020 at 04:47:18PM +0200, pelzflorian (Florian Pelz) wrote:
> However I also cannot find the reason why this usbmouse loadable
> kernel module gets loaded at all.  How can I debug what loads this
> kernel module?  Debian does not show usbmouse in lsmod, and I think
> usbmouse should not get loaded in Guix either.  usbmouse is not
> required for my external USB mouse to work.

Debian 10’s /boot/config-4.19.0-6-amd64 has

# USB HID Boot Protocol drivers
#
# CONFIG_USB_KBD is not set
# CONFIG_USB_MOUSE is not set

while Guix has in /tmp/guix-build-linux-libre-5.4.32.drv-0/linux-5.4.32/.config

CONFIG_USB_MOUSE=m

I will write and test a patch to disable the module in
%default-extra-linux-options, like the description in linux-5.4.11
source file drivers/hid/usbhid/Kconfig recommends:

config USB_MOUSE
        tristate "USB HIDBP Mouse (simple Boot) support"
        depends on USB && INPUT
        ---help---
          Say Y here only if you are absolutely sure that you don't want
          to use the generic HID driver for your USB mouse and prefer
          to use the mouse in its limited Boot Protocol mode instead.

          This is almost certainly not what you want.  This is mostly
          useful for embedded applications or simple mice.

          To compile this driver as a module, choose M here: the
          module will be called usbmouse.

          If even remotely unsure, say N.

Regards,
Florian