Closure.
Kicking myself utterly over this one. My EMS USB2 PlayStation joypad converters are now working perfectly again.
The problem was that the device has a physical switch which is used for swapping between PC mode and Lightgun-with-a-PS2 mode. It appears I'd somehow managed to accidentally flick that switch.
Setting it back to PC, and it all works straight out of the box again. Very silly schoolboy error and had nothing to do with the computer hardware upgrade or the KDE and Linux kernel updates, after all.
Peter.
$ dmesg <SNIP> [ 88.344380] usb 2-1: new full speed USB device using ohci_hcd and address 2 [ 88.862908] usb 2-1: string descriptor 0 read error: -32 [ 88.862908] usb 2-1: New USB device found, idVendor=0b43, idProduct=0003 [ 88.862908] usb 2-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 88.862908] usb 2-1: configuration #1 chosen from 1 choice [ 89.212286] usbcore: registered new interface driver hiddev [ 89.262223] input: HID 0b43:0003 as /devices/pci0000:00/0000:00:06.0/usb2/2-1/2-1:1.0/input/input7 [ 89.262223] input: HID 0b43:0003 as /devices/pci0000:00/0000:00:06.0/usb2/2-1/2-1:1.0/input/input8 [ 89.262223] input: HID 0b43:0003 as /devices/pci0000:00/0000:00:06.0/usb2/2-1/2-1:1.0/input/input9 [ 89.262223] input: HID 0b43:0003 as /devices/pci0000:00/0000:00:06.0/usb2/2-1/2-1:1.0/input/input10 [ 89.262223] generic-usb 0003:0B43:0003.0001: input,hidraw0: USB HID v1.00 Joystick [HID 0b43:0003] on usb-0000:00:06.0-1/input0 [ 89.262223] usbcore: registered new interface driver usbhid [ 89.262223] usbhid: v2.6:USB HID core driver $
$ lsusb Bus 002 Device 002: ID 0b43:0003 Play.com, Inc. PS2 Controller Converter <SNIP> $