Another USB Dock (Cheap)


I found another USB dock for the Librem5, ok there will certainly be a lot … :slight_smile: I found the price performance very good. 6 euros or 7 dollars and you have USB, HDMI and PD to go. Works flawlessly.

Here is the link where I ordered it

Here some more pictures:


In your experience, does it matter which way you turn the USB-C connector?

I mean, it is symmetric and I’m sure it’s intended to work both ways, but I have noticed that in practice it sometimes matters, some things will not work if the supposedly symmetric cable connector is turned “the wrong way”. And for a USB-C-to-USB-C cable there are four possibilities to try.

Is it a fundamental mistake in the design of USB-C that it was made symmetric, when in fact there is no guarantee that it will work like a symmetric thing in practice? To me at least it seems like it would have been much better to not have it symmetric. On the changing cable for my Librem 5 I put a piece of tape to remind me of the “correct” orientation to avoid having to test both ways every time.


@Skalman Good question, I trust the technology … :slight_smile: I use four different power supplies, several cables and adapters and so far I haven’t paid attention to how I plug them in. So far everything has worked as expected.

Something I noticed, you have to exit the dock mode before you pull the dock off, otherwise the phone crashes and wants to be restarted.


I think normally it should work in all orientations.
I had a similar issue.

What does the following output:
sudo dmesg | grep tps

It gives this:

[    6.492861] power_supply bq25890-charger: bq25890-charger: Found supply : tps6598x-source-psy-0-003f

But that is from when it booted, it always says that regardless of the cable being plugged in or not. Doing sudo dmesg | grep tps shows nothing new after plugging in the cable, regardless of how the cable is turned.

Okay, so not the same I had.
I don’t get any response from it.

You could try to ask in Matrix chat for help.

Thanks, it’s not critical anyway, I will investigate it more later.

Or to ensure that compliance with USB-C standards means that it is guaranteed to work?

There was a time when ethernet controllers didn’t support auto-crossover and you had to worry about the nature of the port at each end and whether the cable (straight-through or crossover) was the right cable for that pair of ports. Would anyone want to go back to those days? I think not.

I can see what the USB consortium were trying to achieve with having a symmetric cable.

One of the benefits of a symmetric cable is when plugging in to a port that is in a confined space, and/or where you can’t easily see the host end in order to orient the cable correctly - or just because your eyesight is a bit crap. (That probably doesn’t apply so much for the Librem 5 / dock / power supply scenario.)


I just found (unintentionally) answer (at least partial answer … as which PD power supply actually in use might extend it) to your question:

Another one for comparison:

In short, PD trigger function needs to be activated (as manufacturer demonstrated), and as related to your use case as well. Therefore I would guess that this feature belongs to E-Mark chip, to the one that is used within some particular USB-C to USB-C cable (and communicate with the particular/real PD power supply just when cable flipped into proper position, properly connected on one side).

Actually it is about the protected way (ideal one, as in advance taken care when with Librem 5 distributed cable used to charge it). Which side is proper, as I already referred toward to me unknown PD power supply, you know already.

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