Jakub Kicinski <kuba@xxxxxxxxxx> > Sent: Friday, January 14, 2022 12:17 PM [...] > Dunno much about USB but it seems the driver matches: > > USB_DEVICE_INTERFACE_CLASS(vend, prod, USB_CLASS_VENDOR_SPEC), > \ > > and > > USB_DEVICE_AND_INTERFACE_INFO(vend, prod, USB_CLASS_COMM, \ > USB_CDC_SUBCLASS_ETHERNET, USB_CDC_PROTO_NONE), \ > > Both of these should match. Former because: > > Bus 002 Device 002: ID 0bda:8156 Realtek Semiconductor Corp. USB > 10/100/1G/2.5G LAN > [...] > Interface Descriptor: > bLength 9 > bDescriptorType 4 > bInterfaceNumber 0 > bAlternateSetting 0 > bNumEndpoints 3 > bInterfaceClass 255 Vendor Specific Class > bInterfaceSubClass 255 Vendor Specific Subclass > > And the latter because of another config with: > > bInterfaceClass 2 Communications > bInterfaceSubClass 6 Ethernet Networking > bInterfaceProtocol 0 There are three configurations for RTL8156. config #1: vendor mode (r8152) config #2: NCM mode (cdc_ncm) config #3: ECM mode (cdc_ether) The USB core selects config #2 for default, so cdc_ncm is loaded. If you plan to use vendor mode, you have to switch the configuration to config #1. For example, echo 1 > /sys/bus/usb/devices/2-7/bConfigurationValue Best Regards, Hayes
