Librem 5 "Batteryless" Dock Support

Hey all, my Librem 5 Evergreen that I received in April is able to dock to my old Pinephone dock that has 2 USBs and an HDMI port, which lets me attach a standard mouse, keyboard, and monitor and then use the Librem 5 as though it were a desktop.

But I also would enjoy not using the battery when I pretend my Librem 5 is a desktop. And although I can remove the battery and then use the Librem 5 normally simply by plugging in the “batteryless” device, the same is not true of the dock. When connected through the dock, it seems the “batteryless” Librem 5 does not receive sufficient power and it bootloops instead of functioning normally as it would without the dock.

So it seems that the dock I am using does not forward sufficient power through the device to support a batteryless docked experience. Does anyone know of dock brands that do provide sufficient power? For example, would the NexDock brand mentioned elsewhere on the Purism forums support “docking without a battery” in this way?

Not directly answering your question but

  • does it help to boot the Librem 5 with all switches off? Then progressively turn on the switches. In particular, keeping the WiFi/BT switch off and the cellular switch off until after successful(?) boot?
  • likewise you could try booting without peripherals attached to the dock?
  • if you really want to know what’s going on then you need a USB meter so that you can monitor the power negotiation between the dock and the phone (but I’m not sure how well that would work with video over USB-C)
  • depends on how much time and dollars you want to put into this but what about the dock that Purism actually sells?

That’s not directly comparable because NexDock is a lapdock. That means that it has the keyboard, trackpad and monitor built-in. So it’s not really your use case unless you want to change your use case. (In other words, you are pretending that you have a desktop whereas a lapdock means pretending that you have a laptop.)

Consequently the NexDock is much more expensive than a basic dock such as I imagine you are using.

It also has a battery built-in, which muddies the waters as far as what appears to be the problem (and ultimately would mean that you are not batteryless).

Quite apart from any of the above, running batteryless may have implications for your battery calibration.

How can I check if it has implications for battery calibration?

My understanding is that if you remove the battery then calibration will be lost - and so it will take a few charge/discharge cycles to recalibrate.

If you only use your phone as a desktop, that might not be a problem. However it seems unlikely that you would only ever use your phone as a desktop.

So the effect could be that the displayed battery percentage is less reliable (less accurate) on your phone as compared with the phone of a user with a conventional usage.

Did you update the Librem 5’s USB-C PD firmware?

I didn’t even realize there was an update for that. That is separate from the OS updates, correct?

Yes, it is independent.

For an “April” phone, it is probably already up to date but it doesn’t hurt to check.

sudo cat /sys/kernel/debug/tps6598x/0-003f/customer_use

If you get

0x4c35445000000200

then, as far as I know, you are up to date.

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What power supply are you using?
Does it supply enough power to feed the dock and the L5 together?
Also, cables can be causing power problems.