[GTALUG] USB power reporting Type-c super speed skirmish and libpartd error

[Lennart Sorensen]

On Wed, Sep 23, 2020 at 11:36:39AM -0400, Russell Reiter via talk wrote:
> I've made some progress and then lost it again. I had to take a high def
> photo of the writing on the cable to read that the cable is rated 3.0 and
> my mb is only rated 3.0 but the peripheral card is usb 3.1. I think this is
> why the mb connection hangs the system on usb 3.0, but the peripheral 3.1
> card does not. I'm not sure which iteration of usb provides "alternative"
> bus capabilities, ie. video and up to 100w power.

USB 3 naming is crazy.  My understanding is:

USB 3.0 = USB 3.1 Gen 1 = USB 3.2 Gen 1x1 = 5Gbps
          USB 3.1 Gen 2 = USB 3.2 Gen 2x1 = 10Gbps
                          USB 3.2 Gen 1x2 = 10Gbps (requires USB-C)
                          USB 3.2 Gen 2x2 = 20Gbps (requires USB-C)

So a USB 3.0 port is also a USB 3.1 Gen 1 and a USB 3.2 Gen 1x1 port.

Confusing enough?

As for power, USB-PD (power delivery) allows USB-C to provide 2A at 5V
or up to 3A or 5A at 12V and 20V, for a maximum of 100W.  They start
at standard USB 5V, then negotiate what each end supports and if in
agreement, switch the voltage and current.

-- 
Len Sorensen