I'm not sure if anyone can glean any insight from the attached dmesg output but my edison just dumped the usb serial devices (and hub).
The context is that I have two prolific USB serial devices connected to the edison (mini breakout) via a USB hub and OTG cable.
When the incident happened I was only using one of the serial ports with a program.
The program polls a solar inverter for energy output. Suspiciously this incident occurred just after the sun came up and the inverter started sending responses.
It wasn't immediately after as some messages were received but it was shortly after.
This system was running well for over 12 hours on the previous day
Normally the prolific devices are lit up with leds but after this event they were both without power.
Several reboots did nothing. I had to physically pull the usb otg plug an reattach.
It's a bit embarrassing when an old laptop running XP has been doing this job for years without fail but now...
[82121.067159] pmic_ccsm pmic_ccsm: USB VBUS Removed. Notifying OTG driver
[82121.269484] dwc3-host dwc3-host.2: remove, state 4
[82121.269543] usb usb2: USB disconnect, device number 1
[82121.270166] xHCI xhci_drop_endpoint called for root hub
[82121.270188] xHCI xhci_check_bandwidth called for root hub
[82121.291381] dwc3-host dwc3-host.2: USB bus 2 deregistered
[82121.291829] dwc3-host dwc3-host.2: remove, state 1
[82121.291875] usb usb1: USB disconnect, device number 1
[82121.291898] usb 1-1: USB disconnect, device number 2
[82121.291919] usb 1-1.3: USB disconnect, device number 3
[82121.293564] pl2303 ttyUSB0: pl2303 converter now disconnected from ttyUSB0
[82121.293696] pl2303 1-1.3:1.0: device disconnected
[82121.300243] usb 1-1.4: USB disconnect, device number 4
[82121.301607] pl2303 ttyUSB1: pl2303 converter now disconnected from ttyUSB1
[82121.301692] pl2303 1-1.4:1.0: device disconnected
[82121.305539] xHCI xhci_drop_endpoint called for root hub
[82121.305563] xHCI xhci_check_bandwidth called for root hub
[82121.306472] dwc3-host dwc3-host.2: USB bus 1 deregistered