Sony backlight regression from 2.6.28 to 29-rc

[Norbert Preining <preining@logic.at>]

Dear all,

there is a regression from 2.6.28 to 2.6.29-rc, namely that the
backlight cannot be controlled anymore.

Previously I was able to get a working backlight control with late
2.6.28 kernels, not sure if I needed some patches posted by Mattia.

Now, with 2.6.29-rc2 with and without these patches the backlight does
not work at all, no change.

INterestingly changing the "values" in the sys-files does work (via
/sys/class/backlight/acpi_video0/brightness), either per hand or using
xbacklight. but there is no effect on the actual brightness.

And the sony_laptop sys entries have lost their brightness values.

Is there a way to restore this behaviour?

(Even better, get sony_laptop fixed completely?)

Hardware: Vaio VGN-Z11

Best wishes

Norbert

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Dr. Norbert Preining <preining@logic.at>        Vienna University of Technology
Debian Developer <preining@debian.org>                         Debian TeX Group
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