Jiri and Benjamin: Please look at Bugzilla # 209137: https://bugzilla.kernel.org/show_bug.cgi?id=209137 Somewhere between 5.0 and 5.4, the logitech-djreceiver driver stopped binding to the user's Logitech wireless device. Here are relevant parts of the kernel logs. From 5.0 (working): [ 2.857770] logitech-djreceiver 0003:046D:C52B.0003: hiddev0,hidraw0: USB HID v1.11 Device [Logitech USB Receiver] on usb-0000:00:14.0-4/input2 [ 2.985339] input: Logitech Unifying Device. Wireless PID:1024 Mouse as /devices/pci0000:00/0000:00:14.0/usb3/3-4/3-4:1.2/0003:046D:C52B.0003/0003:046D:1024.0004/input/input13 [ 2.985410] hid-generic 0003:046D:1024.0004: input,hidraw1: USB HID v1.11 Mouse [Logitech Unifying Device. Wireless PID:1024] on usb-0000:00:14.0-4:1 [ 2.995266] input: Logitech K520 as /devices/pci0000:00/0000:00:14.0/usb3/3-4/3-4:1.2/0003:046D:C52B.0003/0003:046D:2011.0005/input/input17 [ 3.026985] logitech-hidpp-device 0003:046D:2011.0005: input,hidraw1: USB HID v1.11 Keyboard [Logitech K520] on usb-0000:00:14.0-4:2 [ 3.033173] input: Logitech M310 as /devices/pci0000:00/0000:00:14.0/usb3/3-4/3-4:1.2/0003:046D:C52B.0003/0003:046D:1024.0004/input/input18 [ 3.033358] logitech-hidpp-device 0003:046D:1024.0004: input,hidraw2: USB HID v1.11 Mouse [Logitech M310] on usb-0000:00:14.0-4:1 >From 5.4 (non-working): [ 2.908901] hid-generic 0003:046D:C52B.0001: input,hidraw0: USB HID v1.11 Keyboard [Logitech USB Receiver] on usb-0000:00:14.0-4/input0 [ 2.909003] hid-generic 0003:046D:C52B.0002: unknown main item tag 0x0 [ 2.909016] hid-generic 0003:046D:C52B.0002: unknown main item tag 0x0 [ 2.909019] hid-generic 0003:046D:C52B.0002: unknown main item tag 0x0 [ 2.909023] hid-generic 0003:046D:C52B.0002: unknown main item tag 0x0 [ 2.909030] hid-generic 0003:046D:C52B.0002: unexpected long global item [ 2.909038] hid-generic: probe of 0003:046D:C52B.0002 failed with error -22 [ 2.909196] hid-generic 0003:046D:C52B.0003: hiddev0,hidraw1: USB HID v1.11 Device [Logitech USB Receiver] on usb-0000:00:14.0-4/input2 [ 2.910586] logitech-djreceiver 0003:046D:C52B.0002: unknown main item tag 0x0 [ 2.910601] logitech-djreceiver 0003:046D:C52B.0002: unknown main item tag 0x0 [ 2.910605] logitech-djreceiver 0003:046D:C52B.0002: unknown main item tag 0x0 [ 2.910609] logitech-djreceiver 0003:046D:C52B.0002: unknown main item tag 0x0 [ 2.910616] logitech-djreceiver 0003:046D:C52B.0002: unexpected long global item [ 2.910620] logitech-djreceiver 0003:046D:C52B.0002: logi_dj_probe: parse failed [ 2.910623] logitech-djreceiver: probe of 0003:046D:C52B.0002 failed with error -22 FYI, intf 0 is a boot-interface keyboard, intf 1 is a boot-interface mouse, and intf 2 is the wireless HID interface. It's not immediately obvious to me where the problem lies. Thanks, Alan Stern