Setting kernel parameter for builtin kernel module atkbd

Ask Fedora
1

I have just migrated one of my families computers to Fedora 43. It has a rather old IBM Rapid Access keyboard which is supported by the atkbd driver, but to activate the special keys I need to set the

parm: extra:Enable extra LEDs and keys on IBM RapidAcces, EzKey and similar keyboards (bool)

I have tried adding atkbd.extra=1 to the boot command line, but it seems to have no effect.

Dear old chatGPT suggests I build my own kernel, but that seems a bit onerous and of course I would need to do for each new kernel.

Any help would be appreciated

2

How do you know you have to set this?

Where do you set this?

When you set it does the keyboard work properly?

If so, I’m sure we can find a config or service to make it permanent.

4

Well the parm comes from running modinfo atkbd. It is a PS/2 keyboard, so that is the right driver and I had a read of the source for the driver and it seems to send the correct command bytes, which by various hunting down on the web seem to be “ea71”, see https://aeb.win.tue.nl/linux/kbd/scancodes-6.html. I know historically I did the same for a Windows 2000 driver about 20 years back.

I set the atkbd.extra=1 in /etc/default/grub as GRUB_CMDLINE_LINUX=“rhgb quiet atkbd.extra=1” and then run grub2-mkconfig. I have been doing some more experimenting and am pretty sure it is being applied. (I also added atkbd.reset=1 and tht did appear to reset the keyboard an extra time during the boot process)

Now I’m thinking the atkbd driver may not be doing exactly the right thing for this keyboard.

5

After more reading and hackin g about, I found I also need to put the controller in raw mode, with i8042.direct=1. This did enable the extra keys, well most of them anyway, but I then couldn’t work out how to map them to do useful things. (I’m using Cinnamon desktop)