Dear NVidia Team
We have a custom carrier with an M.2 Key B Slot where we connect an LTE module. The used signals for USB2 are USB1_D_P (Pin 117) and USB1_D_N (Pin 115), the ones for USB3 are USBSS2_RX_P/N (Pin 53 and 51) and USBSS2_TX_P/N (Pin 59 and 57).
Now when we power-on the device, everything works as expected and the LTE module is recognized without any errors. If we then do a software reboot (# sudo reboot), the usb device is not anymore recognized (nothing listed with “lsusb”) and we see the following errors:
[ 8.485709] usb 1-2: new low-speed USB device number 2 using tegra-xusb
[ 8.629486] usb 1-2: device descriptor read/64, error -71
[ 8.870132] usb 1-2: device descriptor read/64, error -71
[ 9.121707] usb 1-2: new low-speed USB device number 3 using tegra-xusb
[ 9.259016] usb 1-2: device descriptor read/64, error -71
[ 9.506082] usb 1-2: device descriptor read/64, error -71
[ 10.033708] usb 1-2: new low-speed USB device number 4 using tegra-xusb
[ 10.041663] usb 1-2: Device not responding to setup address.
[ 10.255068] usb 1-2: Device not responding to setup address.
[ 10.465711] usb 1-2: device not accepting address 4, error -71
[ 10.605571] usb 1-2: new low-speed USB device number 5 using tegra-xusb
[ 10.622749] usb 1-2: Device not responding to setup address.
[ 10.847172] usb 1-2: Device not responding to setup address.
[ 11.061706] usb 1-2: device not accepting address 5, error -71
Here is the full dmesg output after a power-off:
dmesg_ok.txt (74.1 KB)
Here is the full dmesg output in the failure case:
dmesg.txt (73.0 KB)
Here our device tree:
out.dts (310.4 KB)
If we connect the LTE Module via an onboard hub, it always gets correctly enumerated. Kernel Settings like “usbcore.autosuspend=-1” did not help. Weirdly is that the device gets in the failure case recognized as low-speed usb device.
Thank you for your help.
If you need any additional information, let us know.
Best regards