What exactly handles the Fn keys events in my old laptop Asus M5200AE?

tw00084811 · 2013-08-22 07:17:00

All the Fn keys works fine in my old laptop Asus M5200AE with fresh installed arch + xfce4, all the key events shows up on acpi_listen.

However, I was trying to figure out what exactly handles those acpi events like hibernate when some button pressed or brightness adjustment, cause I tried to manage all the acpi events in one file instead of handled by mutiple services or modules (logind, xfce4-power-manager, asus-laptop module...) at one time and causing conflicts.

First I modified logind.conf to ignore those key events, and now xfce4-power-manager works perfectly by the way I told it to do.

Then I try to disable the brightness adjustment functions, so I rmmod the "asus-laptop" acpi module, but turns out those buttons still works! I can still toggle wireless and screen, adjust brightness and hibernate my laptop. And I find out, as the module been removed, some key events are no longer showing up on acpi_listen, but power button and hibernate key still do.

So I'm just curious, what exactly handles those key events? Could it be controlled directly by firmware or bios without OS? Or is there some service or module I didn't kwow?

Trilby · 2013-08-22 11:19:51

The wifi toggle, for one, is handled at the hardware (bios) level. AFAIK, that's the only one that is.

progandy · 2013-08-22 12:35:06

The brightness keys might just be reported as keyboard events (XF86MonBrightnessUp, XF86MonBrightnessDown, XF86Display). xfce handles those events, i guess through the powermanager.

Power and hibernate should be stanardized acpi events and should be working without a special driver, so this is not surprising. The xfce powermanager handles those acpi events.

And the wifi toggle is probably an rfkill switch which is set in hardware. Those switches usually have two levels, hardware and software. If the hardware switch is used, linux can do nothing.

tw00084811 · 2013-08-23 14:23:44

So there must have some hardware bonding between those buttons... good to know

After reading the documentation about asus-laptop module, I decided to set the module into "pass acpi event only" mode and handled with acpid service.

WonderWoofy · 2013-08-23 14:37:14

I see in your first post that you rmmod'ed th asus-laptop module. But maybe had you done a 'modprobe -r asus-laptop' it might have removed whatever was controlling that functionality. The rmmod command will do exactly as you tell it, that is, it will simply remove that one module. The modprobe command deals with module depndencies as well. So using 'modprobe -r' will remove the specified module, but also any other modules that it depends on that are also not being used by any other modules.

I really have no idea if this will change anything or not. I like asus machines, but I own a thinkpad. The thinkpad-acpi module allows for some pretty in-depth control of those special buttons and their functions.

tw00084811 · 2013-08-24 12:04:47

Had tried 'modprobe -r', but those functions still works, I guess there might have real hardware binding.

I own a thinkpad too! Next laptop definitely gonna be a thinkpad cause I really fall in love with trackpoint
The old asus laptop belonged to my advisor. He was planning to throw it away cause it was too old for windows, so I took it and make it alive with fresh Archlinux!

Arch Linux

#1 2013-08-22 07:17:00

What exactly handles the Fn keys events in my old laptop Asus M5200AE?

#2 2013-08-22 11:19:51

Re: What exactly handles the Fn keys events in my old laptop Asus M5200AE?

#3 2013-08-22 12:35:06

Re: What exactly handles the Fn keys events in my old laptop Asus M5200AE?

#4 2013-08-23 14:23:44

Re: What exactly handles the Fn keys events in my old laptop Asus M5200AE?

#5 2013-08-23 14:37:14

Re: What exactly handles the Fn keys events in my old laptop Asus M5200AE?

#6 2013-08-24 12:04:47

Re: What exactly handles the Fn keys events in my old laptop Asus M5200AE?

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