On 13/12/2018 10:29, Richard van der Hoff wrote:
Thanks for looking at it. I've attached a log from a 4.19.8 kernel
showing the problem with the dynamic debug flags you suggested. The
first instance of the problem seems to begin with:
Dec 13 09:32:56 fred kernel: [ 479.158038] xhci_hcd 0000:39:00.0:
Port Status Change Event for port 1
Dec 13 09:32:56 fred kernel: [ 479.158045] xhci_hcd 0000:39:00.0:
handle_port_status: starting port polling.
Dec 13 09:32:56 fred kernel: [ 479.158062] hub 3-0:1.0: state 7 ports
2 chg 0000 evt 0002
Dec 13 09:32:56 fred kernel: [ 479.158070] xhci_hcd 0000:39:00.0: get
port status, actual port 0 status = 0x202a0
Dec 13 09:32:56 fred kernel: [ 479.158071] xhci_hcd 0000:39:00.0: Get
port status returned 0x10100
Dec 13 09:32:56 fred kernel: [ 479.158083] xhci_hcd 0000:39:00.0:
clear port connect change, actual port 0 status = 0x2a0
Dec 13 09:32:56 fred kernel: [ 479.158087] usb usb3-port1: status
0100, change 0001, 12 Mb/s
Dec 13 09:32:56 fred kernel: [ 479.158095] usb 3-1: USB disconnect,
device number 2
Dec 13 09:32:56 fred kernel: [ 479.158097] usb 3-1.1: USB disconnect,
device number 3
Dec 13 09:32:56 fred kernel: [ 479.158098] usb 3-1.1.3: USB
disconnect, device number 8
Dec 13 09:32:56 fred kernel: [ 479.158100] usb 3-1.1.3: unregistering
device
Mika, Mathias: sorry to pester. I've been trying to decode this with the
help of the source. Any clues?
My impression is that "get port status, actual port 0 status = 0x202a0"
means that the xhci controller is reporting a zero value for the port
status and control register - ie, that the dock is disconnected. If
that's the case, it presumably points fairly firmly to a hardware issue
of some kind.
It would be really helpful to get your thoughts on this.
