On Wed, Jan 26, 2022 at 12:11 AM Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > > On Mon, Jan 24, 2022 at 04:55:22PM +0200, Mathias Nyman wrote: > > > > > [ 0.000000] xhci_dbc:early_xdbc_parse_parameter: dbgp_num: 0 > > > [ 4.984106] xhci_dbc:xdbc_start: waiting for connection timed out, DCPORTSC:0xa0 > > > [ 9.946159] xhci_dbc:xdbc_start: waiting for connection timed out, DCPORTSC:0xa0 > > > [ 9.946163] xhci_dbc:early_xdbc_setup_hardware: failed to setup the connection to host > > > > > > [ 12.818364] xhci_hcd 0000:00:0d.0: xHCI Host Controller > > > [ 12.818373] xhci_hcd 0000:00:0d.0: new USB bus registered, assigned bus number 1 > > > [ 12.820360] xhci_hcd 0000:00:0d.0: xHCI Host Controller > > > [ 12.820363] xhci_hcd 0000:00:0d.0: new USB bus registered, assigned bus number 2 > > > [ 12.821036] xhci_hcd 0000:00:14.0: xHCI Host Controller > > > [ 12.821040] xhci_hcd 0000:00:14.0: new USB bus registered, assigned bus number 3 > > > [ 12.823451] xhci_hcd 0000:00:14.0: xHCI Host Controller > > > [ 12.823453] xhci_hcd 0000:00:14.0: new USB bus registered, assigned bus number 4 > > > [ 17.115089] usb usb4-port4: Cannot enable. Maybe the USB cable is bad? > > > [ 17.115163] usb usb4-port4: config error > > > > Ok, I see it now. > > Your setup has two xhci controllers, earlypringk=dbc enables dbc on the first xhci > > it finds, which would be at 0000:00:0d.0. > > Your cable is connected to the second xhci host at 0000:00:14.0 > > I suspect the first xhci controller is for the usb-c ports on the > machine, while the second one has the usb-a ports covered. > > Now the documentation states we need this super speed A<->A cable, but > could you also update the documentation for usb-c ? There's a fair > number of usb-c only devices out there now. > > C<->A and C<->C cables are fairly easy to come by, would they 'just > work' ? I have used DbC with USB-C to A and it works
