[ltp] T420 /proc/acpi/ibm/video not working

David Woodfall linux-thinkpad@linux-thinkpad.org
Wed, 11 Feb 2015 17:32:08 +0000

Found how to do it with xrandr, so all is well.

Thanks for the replies


>On Sat, 07 Feb 2015, David Woodfall wrote:
>> When I cat /proc/acpi/ibm/video it shows every monitor disabled, even when
>> int and ext are on.
>> Echoing anything there has no effect at all. It all worked fine in my
>> T42. What I would like to do is just use the video_switch command.
>Lenovo abandoned these interfaces a long time ago.
>> Is this a known problem, and is there a workaround?
>None. You have to use something else to video switch :-(
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>  Henrique Holschuh
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