From an initial reading of the commit history I suspect the issue may be caused by e417085e79136d9f955 "drm/i915/dp: Send DPCD ON for MST before phy_up" which deals with power transitions during monitor connect/disconnect.
From an initial reading of the commit history I suspect the issue may be caused by e417085e79136d9f955 "drm/i915/dp: Send DPCD ON for MST before phy_up" which deals with power transitions during monitor connect/disconnect.