USB keyboard problems

Dave Leimbach leimySPAM2k at
Thu Jan 8 00:48:55 PST 2004

Matthew Dillon <dillon at xxxxxxxxxxxxxxxxxxxx> writes:

> :>     Similar problems have been posted to the FreeBSD groups.  The
> :>     concensus seems to be that a lot of BIOSes have severely broken USB
> :>     legacy keyboard support and that you are better off either using 
> :>     a normal PS/2 keyboard, a USB-to-PS2 converter on your keyboard
> :>     cable, or going native USB all the way.
> :> 
> :> 						-Matt
> :
> :Thanks Matt.  It's odd though that linux deals with whatever this problem is
> :seemingly well as well as Windows.
> :
> :The problem this presents for me only occurs when I need to switch what OS 
> :I am booting into as I need to either plug in a PS/2 keyboard or switch
> :legacy support on to be able to navigate GRUB.
> :
> :I will check if there are any BIOS updates for my hardware before diving much
> :deeper all the same.  I've seen hardware work with AGP in Windows and the 
> :Linux drivers couldn't deal with the problem on certain HP systems as well so
> :I know this can be tricky :).
> :
> :I'll keep the list updated if fix is in the BIOS.
> :
> :Dave
>     Another thing you could do is search the FreeBSD archives to see if 
>     there are any USB legacy keyboard issues that have been fixed in 5.x.
>     If so we can backport them.  But I do not recall any from my read of
>     the list.
> 					-Matt
> 					Matthew Dillon 
> 					<dillon at xxxxxxxxxxxxx>

The thing that also makes this seem unlikely is that, if the BIOS is doing
its job properly, the USB keyboard appears to be PS/2 IIRC.  This makes me
think there should be no code *added* to the kernel to support USB Legacy.

If anything some of the USB code might somehow be able to still detect the
keyboard and is confusing it with the PS/2 emulation provided by BIOS.

At least that's my only working theory.


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