If I plug in a USB-to-Ethernet gadget, the kernel sees something: usb 2-1: new SuperSpeed Gen 1 USB device number 2 using xhci-hcd usb 2-1: New USB device found, idVendor=0b95, idProduct=1790, bcdDevice= 1.00 usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3 usb 2-1: Product: AX88179 usb 2-1: Manufacturer: ASIX Elec. Corp. usb 2-1: SerialNumber: 00000000000012 ax88179_178a 2-1:1.0 eth0: register 'ax88179_178a' at usb-xhci-hcd.0.auto-1, ASIX AX88179 USB 3.0 Gigabit Ethernet, 00:0e:c6:fb:e2:41 usbcore: registered new interface driver ax88179_178a # lsmod Module Size Used by Not tainted ax88179_178a 24576 0 usbnet 32768 1 ax88179_178a mii 20480 2 ax88179_178a,usbnet But the eth LEDs don't turn on (or blink) when I plug in a cable. Could it be a power/voltage issue? # lsusb -v Bus 002 Device 003: ID 0b95:1790 Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 3.00 bDeviceClass 255 bDeviceSubClass 255 bDeviceProtocol 0 bMaxPacketSize0 9 idVendor 0x0b95 idProduct 0x1790 bcdDevice 1.00 iManufacturer 1 ASIX Elec. Corp. iProduct 2 AX88179 iSerial 3 00000000000012 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 0x0039 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 0 bmAttributes 0xa0 (Bus Powered) Remote Wakeup MaxPower 496mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 3 bInterfaceClass 255 bInterfaceSubClass 255 bInterfaceProtocol 0 iInterface 4 Network_Interface Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0008 1x 8 bytes bInterval 11 bMaxBurst 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x82 EP 2 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0400 1x 1024 bytes bInterval 0 bMaxBurst 3 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x03 EP 3 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0400 1x 1024 bytes bInterval 0 bMaxBurst 15 Binary Object Store Descriptor: bLength 5 bDescriptorType 15 wTotalLength 0x0016 bNumDeviceCaps 2 USB 2.0 Extension Device Capability: bLength 7 bDescriptorType 16 bDevCapabilityType 2 bmAttributes 0x00000002 HIRD Link Power Management (LPM) Supported SuperSpeed USB Device Capability: bLength 10 bDescriptorType 16 bDevCapabilityType 3 bmAttributes 0x00 wSpeedsSupported 0x000e Device can operate at Full Speed (12Mbps) Device can operate at High Speed (480Mbps) Device can operate at SuperSpeed (5Gbps) bFunctionalitySupport 1 Lowest fully-functional device speed is Full Speed (12Mbps) bU1DevExitLat 1 micro seconds bU2DevExitLat 101 micro seconds can't get debug descriptor: Resource temporarily unavailable Device Status: 0x0000 (Bus Powered)