Input: vmmouse - remove port reservation
authorSinclair Yeh <syeh@vmware.com>
Fri, 24 Jun 2016 00:37:34 +0000 (17:37 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 10 Aug 2016 09:49:26 +0000 (11:49 +0200)
commit12a83f6702402803190450218c0a80a1d5fb2b09
tree02e0bd46a1eb56806ed15256ceac1fb023d59f70
parent8fd58e050f90ed5d5161413c75a8a8271934566c
Input: vmmouse - remove port reservation

commit 60842ef8128e7bf58c024814cd0dc14319232b6c upstream.

The VMWare EFI BIOS will expose port 0x5658 as an ACPI resource.  This
causes the port to be reserved by the APCI module as the system comes up,
making it unavailable to be reserved again by other drivers, thus
preserving this VMWare port for special use in a VMWare guest.

This port is designed to be shared among multiple VMWare services, such as
the VMMOUSE.  Because of this, VMMOUSE should not try to reserve this port
on its own.

The VMWare non-EFI BIOS does not do this to preserve compatibility with
existing/legacy VMs.  It is known that there is small chance a VM may be
configured such that these ports get reserved by other non-VMWare devices,
and if this ever happens, the result is undefined.

Signed-off-by: Sinclair Yeh <syeh@vmware.com>
Reviewed-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/input/mouse/vmmouse.c