Lenovo Y570 backlight

[matt]

On 07/12/12 05:06, SicoSico wrote:
> Thanks for your reply Erich Dollansky-2,
>
> #kldload acpi_call
> #acpi_call -p '\VBRC' -i 8
> Unknown object type '-1515870811'
>
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You could also try kldloading acpi_video and using its sysctl interface 
(man acpi_video, I'm not on a machine it attaches to right now).

VBRC is non-standard (as far as I know), BCL I think is the ACPI 
"standard" way of talking to the backlight. For some values of standard, 
anyway. BCL is what acpi_video looks for and talks to, but you may have 
a non-standard brightness acpi call. If that's the case, you'd have to 
dig through an ACPI dump for graphics references and try to find stuff 
that looks brightness related.

With any luck, Lenovo uses a more traditional ACPI interface to it's 
non-ThinkPad lines and acpi_video will work...

Matt