[coreboot] Thinkpad X230 Thinklight always on

[Gert Menke]

Hi,

I just got my new backlit keyboard and ran into a slight annoyance.

When I set the backlight option in nvram to "Both" or "Thinklight only", 
it works as expected: Fn+Space toggles the Thinklight or Turns on the 
keyboard backlight, then the Thinklight, then off.

However, when I set it to backlight="Keyboard only", the Thinklight 
lights up on power on, and stays on forever. The keyboard backlight 
behaves as expected, though.

Normally, the Thinklight lights up for about a second when the system is 
powered on. I suspect that coreboot tells the EC to disregard the 
Thinklight somewhere within this timepsan, so the EC never bothers to 
turn it off again. Does that make sense?

I looked into h8.c and found the place where the relevant bit of EC 
configuration happens (it's bit 3 and 2 of address 0x01). But I have no 
idea how to fix this.

A workaround for now is to set backlight="Both" and use "ectool -w 0x01 
-z 0x05" in /etc/rc.local.

Any ideas how to fix this properly?

Cheers
Gert