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Fn-PgUp key is supposed to turn on the little keyboard lamp on Lenovo. It used to work on my T61 and older models, but no longer on X220. Ideas anyone?

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Please run sudo acpi_listen in the terminal, press Fn+PgUp and edit answer/comment with what code appears. – izx May 24 '12 at 12:02
Nothing. The above command does not yield any output in response to Fn+PgUp. It does generate codes for other Fn combinations, but not for this one. – Yossi Gil May 26 '12 at 11:20
Does it work when in BIOS? – izx May 31 '12 at 8:29
It works when I boot it up in Windows 7. – Yossi Gil Jun 6 '12 at 3:59

1. Figuring out the key code emitted by Fn+PgUp

  • You can use the lsinput and input-events commands to look at the output of the Fn+PgUp combination.

  • Then you can assign the key combination via the ACPI Event Definition as defined here.

2. Shell commands to switch on-off: can be integrated in ACPI Events, shortcut keys, etc.

Switch on the lamp:

echo 255 > /sys/class/leds/tpacpi\:\:thinklight/brightness

Switch off the lamp:

echo 0 > /sys/class/leds/tpacpi\:\:thinklight/brightness

For more information regarding ThinkLight on Linux:

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OP wants to use the key combo, not soft control. – izx Jun 1 '12 at 2:52
@izx I have improved my answer. – pl1nk Jun 1 '12 at 10:16
Can you please provide more details on the implementation details? – Yossi Gil Jun 4 '12 at 5:08
@YossiGil As izx mentioned, does the lamp work while you are in BIOS menu screen? Furthermore what is the output of lsmod |grep thinkpad . Why I'm keeping downvoted ?? – pl1nk Jun 4 '12 at 10:55
I must be doing something wrong. The echo command does not work in that it does not change the light status. Further, I still cannot figure out the scan code. – Yossi Gil Jun 6 '12 at 4:03

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