Comment 121 for bug 173652

With "xrandr --output LVDS --set BACKLIGHT_CONTROL native" I can adjust my lcd brightness using xbacklight by I am still unable to get my function keys detected.

https://bugs.launchpad.net/ubuntu/+source/linux-source-2.6.15/+bug/38323

I have a sony vaio VGN-CR220e I wonder when my laptop's function keys will be supported by linux

Sean Coleman wrote:
> I have a fairly recent model: Sony VGN-NR498E, Intel X3100.
>
> With a fresh install of 8.10, the function keys cause the backlight OSD
> to move up and down properly, however there is no adjustment to the
> backlight.
>
> If I use the command "xrandr --output LVDS --set BACKLIGHT_CONTROL
> native", I can immediately adjust brightness with the function keys.
> With native, I am subject to what I believe above is being called the
> oscillation bug. This setup is non-functional. Also, with native, if I
> click the power manager icon, the power manager doesn't respond.
>
> On the other hand, If i use the command "xrandr --output LVDS --set
> BACKLIGHT_CONTROL legacy", I have brightness control with the function
> keys, and I don't have the oscillation problem. Some other events do
> adjust brightness (and leave it that way) though, such as going to
> preferences of the power manager dims the display.
>
> With either BACKLIGHT_CONTROL setting, I don't have to use the
> xbacklight command at all, and I don't have xbacklight installed.
>
> At the moment, "BACKLIGHT_CONTROL legacy" is the only tolerable
> situation.
>
>