Zero hops in tb_path_activate before writing a new path.
This fixes the following scenario:
- Boot with a coldplugged device
- Unplug device
- Plug device back in
- PCI hotplug fails
The hotplug operation fails because our new path matches the (now
defunct) path which was setup by the firmware for the coldplugged
device. By writing zeros before writing our path configuration we can
force thunderbolt to retrain the path.
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
A thunderbolt path is a unidirectional channel between two thunderbolt
ports. Two such paths are needed to establish a pci tunnel.
This patch introduces struct tb_path as well as a set of tb_path_*
methods which are used to activate & deactivate paths.
Signed-off-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
