drm/amd/display: Enable mst when it's detected but yet to be initialized

[Why]
drm_dp_mst_topology_queue_probe() is used under the assumption that
mst is already initialized. If we connect system with SST first
then switch to the mst branch during suspend, we will fail probing
topology by calling the wrong API since the mst manager is yet to
be initialized.

[How]
At dm_resume(), once it's detected as mst branc connected, check if
the mst is initialized already. If not, call
dm_helpers_dp_mst_start_top_mgr() instead to initialize mst

V2: Adjust the commit msg a bit

Fixes: bc068194f548 ("drm/amd/display: Don't write DP_MSTM_CTRL after LT")
Cc: Fangzhi Zuo <[email protected]>
Cc: Mario Limonciello <[email protected]>
Cc: Alex Deucher <[email protected]>
Reviewed-by: Tom Chung <[email protected]>
Signed-off-by: Wayne Lin <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>
(cherry picked from commit 62320fb8d91a0bddc44a228203cfa9bfbb5395bd)
Cc: [email protected]

0 files changed, 0 insertions, 0 deletions