thunderbolt: Stop waiting on a path pending bit that never clears

__tb_path_deactivate_hop() waits up to 500 ms for a hop's pending bit to
read back clear. On an ASMedia ASM4242 host router the host interface
adapter latches it once enough frames have gone through the DMA ring and
never clears it again: the teardown finds it already set, seconds after
the last frame and with the path still up. USB4 v2 table 8-23 has the
field read only and zero unless packets belonging to the path are waiting
to be dequeued, so the wait is right and this adapter is not.

Make the wait a per-adapter length and quirk those routers to zero, which
leaves the loop reading the bit exactly once. A hop that does drain still
says so on that read, and one that does not answers -ETIMEDOUT without
burning the timeout: bringing the interface down takes 6 ms where it took
506.

Assisted-by: Claude:claude-opus-5
Signed-off-by: Fan Ye <fy15309206903@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

0 files changed, 0 insertions, 0 deletions