I have a Dell XPS 15 (9550) which have a thunderbolt 3/USB-C port and a Dell TB15 thunderbolt 3 dock.
Also, I'm running GNU/Linux Debian jessie with Linux 4.5.
So far, the dock is unusable in this OS because most of the ports (HDMI, USB, etc.) are not recognized by the kernel.
Only power is recognized (so I can charge the laptop and peripherals).
Some people on Dell forums say that "Intel is working on thunderbolt 3 support for linux".
I was wondering if you guys have more details on that.