acer-wmi auto-loaded on a Lenovo Thinkpad X1 Carbon 4th gen

["Bjørn Mork" <bjorn@mork.no>]

I recently got a new laptop.  And now I'm trying to figure out what all
the stuff they put into it actually is :)
.
One thing that doesn't seem quite right is that the acer-wmi driver is
loaded and claims that this laptop has an "Acer BMA150 accelerometer".

It is true that there is a device there matching

  #define AMW0_GUID1            "67C3371D-95A3-4C37-BB61-DD47B491DAAB"

as can be seen:

 bjorn@miraculix:~$ ls -l /sys/devices/virtual/wmi/67C3371D-95A3-4C37-BB61-DD47B491DAAB
 total 0
 -r--r--r-- 1 root root 4096 Jul 14 23:10 modalias
 drwxr-xr-x 2 root root    0 Jul 14 23:10 power
 lrwxrwxrwx 1 root root    0 Jul 14 23:10 subsystem -> ../../../../class/wmi
 -rw-r--r-- 1 root root 4096 Jul 14 23:10 uevent


But I sort of doubt there is an Acer specific device here.  Maybe this
is a generic accelerometer interface?  Or is there something else going
on?

The input device created by the driver just just returns -EPERM when I
try to open it, so I don't think this actually works as-is:

 root@miraculix:/tmp# cat /dev/input/event8
 cat: /dev/input/event8: Operation not permitted


And it does seem a little weird that a Thinkpad should need an Acer
specific platform driver anyway....  thinkpad_acpi is of course handling
all(?) the Thinkpad specifics as expected.


Bjørn