I just recently bought a TCL 4 series tv. According to the specs on the tv, all 3 of the hdmi ports support hdcp 2.2 - and I've set all of the ports to default to hdmi 2.0
But when i try to view 4k content using a firetv stick, it complains that there's no HDCP 2.2 support. I've tried power cycling the tv, and I tried buying the latest version of the fire tv stick, and it still complains about the lack of HDCP 2.2 support.
And I do have the stick plugged into a power outlet, i'm not trying to power it off the tv's USB port.
this is the first thread that pops in google when searching for tcl hdcp, so i reckon it could be useful for some people:
I had the same issue with hdcp compliancy on my mi box. it sometimes was working, but most of the time it stated compliance on level 1.x or even unprotected. Turns out that the bad guy here was the instant on mode (dunno what it's called in english tv's, but it's a feature that enables the tv and the smart elements of it to stay on all the time so the powering on is instant instead of waiting a few seconds for everything to boot. You have to turn it OFF (as in you want the tv to start slowly) and all of the problems dissapear.