Re: keyboard bound to [dummy device]

[Helge H. <hel...@hi...>]

Hugo Vanwoerkom wrote:

>Hi!
>
>Still have a question:
>
>--- Helge Hafting <hel...@hi...> wrote:
>
><snip>
>
>  
>
>>If you have two framebuffers, one for each card,
>>then I recommend
>>using framebuffer console and no dumbcon for ruby
>>2.6.7.
>>
>>    
>>
>
><snip>
>
>I don't understand that. Dense. :-( How do you assign
>framebuffers to a card? And how many framebuffers do I
>have?
>  
>
You don't really assign framebuffers yourself.  It usually
happens automatically, if you have framebuffer drivers for
your cards.

I have a matrox G550 dualhead card, and my kernel
is compiled with two framebuffers for it, one for each head.
Therefore, /dev/fb0 is the first head and /dev/fb1 is the second.
cat something > /dev/fb0 cause garbage to appear on the
first screen, while cat somthing > /dev/fb1 cause garbage on
the other screen. Using /dev/fb2 gives me ENODEV because
there is no third framebuffer at this time. There
will be when I get my radeon pci card though.


>I do "cat <something> > /dev/fb0 or /dev/fb1 and it
>always ends up on the primary console...
>  
>
Very strange.  Only one of them should refer to
the primary console.  Have you tried higher numbers,
such as fb2, fb3, and so on?

Try "ls -l /dev/fb*" and see
if the device numbers are correct.  You should
get something like this:
crw-rw----  1 root video 29, 0 2004-08-16 15:33 /dev/fb0
crw-rw----  1 root video 29, 1 2004-08-16 15:33 /dev/fb1
crw-rw----  1 root video 29, 2 2004-08-16 15:33 /dev/fb2

The date may be different, but the major number should be 29
and the minors should go from 0 and up.  The devices must have
distinct minor numbers.


You can assign keyboards to consoles - once your framebuffer
oddities are sorted out.
Look at the files in /proc/bus/console
For a 2-keyboard machine with one vgacon and one dummycon I have:

cat /proc/bus/console/00/display_desc
VGA+
cat /proc/bus/console/00/keyboard
isa0060/serio0/input0

cat /proc/bus/console/01/display_desc
dummy device
cat /proc/bus/console/01/keyboard    
isa0060/serio1/input0

These are changeable.  I can swap the two keyboards like this, for example:
echo isa060/serio1/input0 > /proc/bus/console/00/keyboard
echo isa060/serio0/input0 > /proc/bus/console/01/keyboard

(serio1 is the ps2 kbd connector, serio0 is the ps2 mouse connector,
where I have another keyboard instead. My mice are serial mice.)

Helge Hafting