Re: iBook (firewire) backlight
On Thu, 16 Aug 2001, Kin Chung wrote:
> Thanks for the tip. Actually it turns out to be caused by
> not having aty128fb activated (the 2.4.4 kernel version was
> badly behaved, it seems, for just about every imac-like machine
> including the ibook) as I discovered after downloading and
> compiling the 2.4.6 kernel (the 2.4.6 aty128fb works brilliantly).
I haven't had this problem, but I've found that using the 'backlight'
command (from the powerpc-utils package) with the '-a' switch often
doesn't work (won't control the backlight properly), and I have had it
hard-lock the system. Using the '-q' switch instead doesn't do this - it
controls the backlight level correctly, and I haven't had it lock the
laptop.
An 'strace' indicates that with the '-a' switch, it opens /dev/adb, and
tries to use it to control the backlight (getting EINVAL on write, and EIO
on read), and doesn't try anything else, whereas with the '-q' switch, it
tries /dev/adb, then tries /dev/pmu (which, as I said, works right).
Just thought that since the subject had arisen, this was worth mentioning.
Derrik Pates | Sysadmin, Douglas School | #linuxOS on EFnet
dpates@dsdk12.net | District (dsdk12.net) | #linuxOS on OPN
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