We receive a plug event callback whenever a thunderbolt device is added
or removed. This patch fills in the tb_handle_hotplug method and starts
reacting to these events by adding/removing switches from the hierarchy.
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add utility methods tb_port_state and tb_wait_for_port. Add
tb_scan_switch which recursively checks for downstream switches.
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Thunderbolt switches have a plug events capability. This patch adds the
tb_plug_events_active method and uses it to activate plug events during
switch allocation.
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch adds the structures tb_switch and tb_port as well as code to
initialize the root switch.
Signed-off-by: NAndreas Noever <andreas.noever@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>