HID: surface-hid: Use correct event registry for managing HID events
authorMaximilian Luz <luzmaximilian@gmail.com>
Thu, 21 Oct 2021 13:09:03 +0000 (15:09 +0200)
committerHans de Goede <hdegoede@redhat.com>
Fri, 22 Oct 2021 08:54:51 +0000 (10:54 +0200)
commitdc0fd0acb6e0e8025a0a43ada54513b216254fac
treef0b3437b1942bc92de81ba00f953288e49728a68
parent4f042e40199ce8bac6bc2b853e81744ee4ea759c
HID: surface-hid: Use correct event registry for managing HID events

Until now, we have only ever seen the REG-category registry being used
on devices addressed with target ID 2. In fact, we have only ever seen
Surface Aggregator Module (SAM) HID devices with target ID 2. For those
devices, the registry also has to be addressed with target ID 2.

Some devices, like the new Surface Laptop Studio, however, address their
HID devices on target ID 1. As a result of this, any target ID 2
commands time out. This includes event management commands addressed to
the target ID 2 REG-category registry. For these devices, the registry
has to be addressed via target ID 1 instead.

We therefore assume that the target ID of the registry to be used
depends on the target ID of the respective device. Implement this
accordingly.

Note that we currently allow the surface HID driver to only load against
devices with target ID 2, so these timeouts are not happening (yet).
This is just a preparation step before we allow the driver to load
against all target IDs.

Cc: stable@vger.kernel.org # 5.14+
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20211021130904.862610-3-luzmaximilian@gmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
drivers/hid/surface-hid/surface_hid.c
include/linux/surface_aggregator/controller.h