Re: kbd not functioning in 2.5.25-dj2

From: Rogier Wolff (R.E.Wolff@BitWizard.nl)
Date: Sun Jul 14 2002 - 08:36:20 EST


Vojtech Pavlik wrote:
> > > > mice: PS/2 mouse device common for all mice
> > > > atkbd.c: Sent: f5
> > > > atkbd.c: Received fe
> > > > serio: i8042 KBD port at 0x60,0x64 irq 1
[...]
> Responses:
>
> 0xfe
> Resend. Keyboard will send this if it didn't receive the last command
> correctly.
>
> Unfortunately, 0xfe also happens when you send a command to a keyboard
> that's not plugged, or when the keyboard doesn't understand the command.
> Resending in those cases (which are the most common) would cause an
> infinite loop ...

Not if implemented correctly.

Set the retry counter to 5 at the beginning.

    if you get 0xfe: decrement retry counter,
        if 0 :
            no keyboard connected. Give up.
        else
            Just immediately resend the last command
    else
        set the retry counter to 5 again.
        process returned code

Roger.

-- 
** R.E.Wolff@BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2137555 **
*-- BitWizard writes Linux device drivers for any device you may have! --*
* There are old pilots, and there are bold pilots. 
* There are also old, bald pilots. 
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