Hi,
I have tested multiple combinations and seems that following error:
Code:
[pią lis 10 09:12:26 2017 < 0,000072>] [drm:drm_wait_vblank [drm]] *ERROR* Unsupported type value 0x121, supported mask 0x7400003f
happens only when I connect one specific Samsung display (tested it on coworker's display - also Samsung, also via HDMI) and no spam happened. Fortunately I will have it replaced soon.
Today i intend to test all peripherals connected to laptop (with the Samsung display via HDMI) and Dell display via DP via Dock to see if I will get any disconnects. Wish me luck!