thunderbolt: Do not touch CL state configuration during discovery
authorMika Westerberg <mika.westerberg@linux.intel.com>
Wed, 24 May 2023 10:47:04 +0000 (13:47 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 21 Jun 2023 14:00:56 +0000 (16:00 +0200)
commit081b5f1ebc731d74a9b9fe8a0c8d163f7f1aff52
treea4b9a871a4b3b867c6f6962bfece62382988bf1e
parent1eb0eff7da975426b1072528cb5e6bbddd29195c
thunderbolt: Do not touch CL state configuration during discovery

commit 3fe95742af29b8b4eccab2ba94bc521805c6e10c upstream.

If the boot firmware has already established tunnels, especially ones
that have special requirements from the link such as DisplayPort, we
should not blindly enable CL states (nor change the TMU configuration).
Otherwise the existing tunnels may not work as expected.

For this reason, skip the CL state enabling when we go over the existing
topology. This will also keep the TMU settings untouched because we do
not change the TMU configuration when CL states are not enabled.

Reported-by: Koba Ko <koba.ko@canonical.com>
Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/7831
Cc: stable@vger.kernel.org # v6.0+
Acked-By: Yehezkel Bernat <YehezkelShB@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/thunderbolt/tb.c