On Tue, 23 Jan 2018, Samuel Sadok wrote: > Thanks Alan, > > While I was at it I also enabled debug logs for xhci_hcd and xhci_pci. > > $ echo module usbcore =p > /sys/kernel/debug/dynamic_debug/control > $ echo module xhci_hcd =p > /sys/kernel/debug/dynamic_debug/control > $ echo module xhci_pci =p > /sys/kernel/debug/dynamic_debug/control > $ modprobe usbmon > $ cat /sys/kernel/debug/usb/usbmon/0u > /tmp/usbmon.log > $ # press power button > > dmesg: https://gist.github.com/anonymous/29b81574abf40605f999cfeefe98e341 > usbmon: https://gist.github.com/anonymous/55b6d9bbf8b8c8627230b10d2b09dcb6 > > Both logs were collected at the same time so the timestamps should match. In fact they do, quite closely. But there is a noticeable gap in the usbmon trace, between lines 197 and 198 (the timestamp jumps from 35923531 to 38925126) and there obviously was a lot of activity on bus 1 in between. > Resume starts at dmesg line 1255. > As far as I can judge, the earliest indication of something going > wrong is line 1514: > [ 36.087176] xhci_hcd 0000:00:14.0: xHCI xhci_urb_enqueue called with > unaddressed device > [ 36.087180] usb 2-4: Disable of device-initiated U1 failed. > [ 36.087212] xhci_hcd 0000:00:14.0: xHCI xhci_urb_enqueue called with > unaddressed device > [ 36.087224] usb 2-4: Disable of device-initiated U2 failed. > [ 36.087226] xhci_hcd 0000:00:14.0: xHCI xhci_urb_enqueue called with > unaddressed device > [ 36.087227] usb 2-4: usb_reset_and_verify_device Failed to disable LTM Yes, that's where the problem first seems to show up. Apparently usb_disable_ltm() fails because it can't communicate with the device, and usb_reset_and_verify_device() then aborts because of that failure. It shouldn't do this; after all, one very good reason for resetting the device is because we're unable to communicate with it. You could try editing the source code for usb_reset_and_verify_device() in drivers/usb/core/hub.c, to see what happens if it doesn't give up after usb_disable_ltm() fails. However, this does not explain the errors that occur later, notably around line 2008 or a little earlier: [ 42.819016] usb usb2-port4: not enabled, trying warm reset again... [ 42.819020] usb usb2-port4: Cannot enable. Maybe the USB cable is bad? [ 42.819110] xhci_hcd 0000:00:14.0: Cannot set link state. [ 42.819125] usb usb2-port4: cannot disable (err = -32) [ 42.819180] usb usb2-port4: status 0341, change 0010, 5.0 Gb/s [ 42.819185] usb 2-4: USB disconnect, device number 2 Perhaps Mathias can take a look at this, and the error messages that follow, and figure out what's going wrong. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
