Unpredictable power direction with Thunderbolt Dock

Framework Laptop 13 Linux
1

Which Linux distro are you using? NixOS
Which release version? 25.05
Which kernel are you using? 6.16.8
Which BIOS version are you using? 3.16
Which Framework Laptop 13 model are you using? AMD Ryzen™ 7040 Series

I use a Dell TB16 Thunderbolt dock with my Framework. Whenever I try to connect my laptop to my dock, it’s a coin flip of whether or not the dock will charge the device. About 30% of the time, the laptop will only charge and the not connect to the thunderbolt devices. Around 40% of the time, it connects to thunderbolt devices but does not charge. And the rest, will connect correctly.

It seems like this issue is unique to Dell Thunderbolt Docks, as I’ve tried another dock previously that had the same issue. Withframework_tool --pdports, I get the following when the dock is connected but not charging (i.e. with monitors and USB devices semi-working):

USB-C Port 0 (Right Back):
  Role:          Source
  Charging Type: None
  Voltage Now:   5.0 V, Max: 0.0 V
  Current Lim:   0 mA, Max: 1500 mA
  Dual Role:     Charger
  Max Power:     0.0 W

When the dock is successfully connected, as well as when it’s only charging, I get this:

USB-C Port 0 (Right Back):
  Role:          Sink
  Charging Type: PD
  Voltage Now:   0.0 V, Max: 19.500 V
  Current Lim:   3000 mA, Max: 3000 mA
  Dual Role:     Charger
  Max Power:     58.500 W

The dock is powered with a fairly substantial power supply (>100W), so I don’t see why it would be having this issue. Does anyone have any ideas as to why this could be happening or a potential workaround?

2

Sadly this is likely the issue. USB4 is not Thunderbolt no matter what the standard suggests. At best yes they should be the same, but in practice the forum is littered with issues that relate to similar situations. Even Thunderbolt does not guarantee that a particular dock will behave with a particular device. That being said I have not experienced any issues using a TB19 with my 12th gen Intel Framework 13.

3

Is your TB16 firmware fully up to date? If not you should update first. FYI you need to do this from a Dell system. You can’t update it on anything else.

If it’s still happening after updating dock firmware I think you should report this fo Framework support. The PD controller in the dock and laptop seem not to be negotiating properly.