Comment 18 for bug 1678477

Thanks @Kai-Heng Feng for your help. I have installed your kernel and it does seem to work. The boot does not delay for 30 or more seconds anymore, and the keyboard is usable immediately after boot. It still nags a bit:

[ 2.249880] usb 3-1: New USB device found, idVendor=1b1c, idProduct=1b20
[ 2.249881] usb 3-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 2.249882] usb 3-1: Product: Corsair STRAFE RGB Gaming Keyboard
[ 2.249882] usb 3-1: Manufacturer: Corsair
[ 2.249883] usb 3-1: SerialNumber: 1303D038AEA7A44454E1B806F5001944
[ 2.252101] hidraw: raw HID events driver (C) Jiri Kosina
[ 2.254100] usbhid 3-1:1.2: couldn't find an input interrupt endpoint

but so far it seems to work well. I will watch it for a while and report back if there is still trouble.