Thinkpad Edge E220s - setting brightness freezes linux

Hi,

the topic well describes the problem, I am running Ubuntu 11.04 witl latest kernel, Ican set brightness in Win, or during boot, but after kernel is loaded it causes freezes.
All other features work out of the box, I tried with console only as well.

do you have any ideas how to solve this, or do you experience this with e420, 520?

 

Have you tried other distros? Generally I find that openSUSE and Arch work in places that Ubuntu doesn't, and vice-versa. I can't say that I know what the problem is but trying that out and posting results might help people here.

Also you mention that during boot it's fine, is that after GRUB?

 

I haven't tried other distros, only ubuntu. It produced the same with live cd a well. A far as I understand, the brightness is set by bios, but acpi call is messed up. Maybe this is a bug in thinkpad acpi, I will try an other live cd. Anyone else with similar issues?

Oh an one last thing: if I rmmod thinkpad-acpi than I can set it 2-6 times, but it freezes again.

 

I've just found this on a mailing list:


> I just got an Edge e220s, and am having some issues. If I press Fn-F7
> (lower screen brightness) two times or Fn-F8 (increase brightness) the
> laptop freezes up solid. I get an unhandled HKEY 0x6050 message from
> Fn-F7 the first time I press it, but I'm not thinking thinkpad_acpi is
> the culprit, since the behavior is the same (2nd F7, 1st F8 freezes
> laptop) even without the module loaded.
>
> Do you have any advice or insight into this issue, or how to diagnose
> the cause of this issue?

[ccing linux-acpi too]

Self-replying..

Apparently the hang is ACPI-related, it only happens when using ACPI
backlight controls. It works if acpi=off, but that's not really a good
solution these days. I think this means I'm out of luck without a BIOS
update -- the backlight ASL (avail on request) ends up calling a "SMI"
method, so the trail ends there.

I also found out that blacklisting the video module doesn't work,
perhaps because i915 depends on it?

Another weird thing is that acpi_backlight=vendor causes it to hang,
right before gdm screen comes up, so that's not an option either, alas.

Cmon Lenovo bios people, I thought you had a clue!

 

just tested with Fedora live cd: same results

 

Yeah, just read the mailing list, it's not exactly something that could be distro-related. 39 is going downstream slowly, if it still doesn't work with that the only other option would be to start spamming mailing lists . Sorry I can't be much more help.

 

I guess this is an ACPI or a bios issue, first we shall find out which one

 

if i add the boot option 'noapic' it gets resolved, still a fixed bios would be fine...

 

Have you asked on the Ubuntu mailing list/IRC?

 

Does it also hang if you use the "xbacklight" command or if you echo brightness level to /sys/class/backlight/acpi_video0/brightness?

 

/sys/class/backlight/acpi_video0/brightness is not populated, so xbacklight doesn't work.