If a Sixaxis or Dualshock 4 controller is connected via USB while already
connected via Bluetooth it will cause duplicate devices to be added to the
input device list.
To prevent this a global list of controllers and their MAC addresses is
maintained and new controllers are checked against this list. If a duplicate
is found, the probe function will exit with -EEXIST.
On USB the MAC is retrieved via a feature report. On Bluetooth neither
controller reports the MAC address in a feature report so the MAC is parsed from
the uniq string. As uniq cannot be guaranteed to be a MAC address in every case
(uHID or the behavior of HIDP changing) a parsing failure will not prevent the
connection.
Signed-off-by: Frank Praznik <frank.praznik@oh.rr.com>
Reviewed-by: David Herrmann <dh.herrmann@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
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