PC (ISA) keyboard controller
pckbc* at isa? flags 0x00 (alpha, amd64,
pckbc* at ebus? (sparc64)
pckbd* at pckbc?
pms* at pckbc?
pckbc driver handles resource
allocation and device attachment for the traditional PC/AT keyboard
controller. It provides two logical connections for child devices, the
“keyboard” slot for a keyboard and the
“auxiliary” slot for mice (the latter might be missing in
older keyboard controllers).
To avoid attaching a phantom PS/2 keyboard device, the
pckbc driver will attempt to detect USB legacy
keyboard emulation on amd64 and i386 systems. Unfortunately, the detection
heuristics may fail on older systems with a real PS/2 keyboard. The keyboard
can be forced to attach on these systems, by changing the device flags to
ebus(4), intro(4), isa(4), pckbd(4), pms(4), boot_config(8)