Re: [PATCH]: ACPI: Skip the first two elements in the _BCL package

[Len Brown <lenb@kernel.org>]

> I remember that Rui pointed me to a brightness level list, which included
> a value in AC/battery values which was not in the rest of the list.

if that is true, then I like your idea better.
we should make sure that the ac and dc values appear on the list.

> I expect simply ignoring battery/AC values is not right.
> I posted a patch a while ago which did:
>   - Go through the brightness values and extract from all (including
>     AC and battery) unique values
>   - Sort them
>   - Create a with the data a new list.
> Not sure whether this would have worked, but something is still
> missing. Currently we do not use battery/AC values, but what if we want
> do that, e.g. exporting them to userspace?

I should think that it would be prudent to expose the
ac and dc defaults to user-space -- allowing user-space
to over-ride them, and then on ac events doing the
brightness switch in the kernel.  That way it will work
even w/o teaching user-space new tricks.

thanks,
-Len

> > http://bugzilla.kernel.org/show_bug.cgi?id=12450