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I have A Sony VAIO laptop F-series () Nvidia and it has light sensor. When I was using Windows, this light sensor controlled the brightness and the keyboard backlight automatically due to the surroundings state.

But when using Ubuntu 12.04, it only controls the backlight without automatically adjusting the brightness.

How can I enable light sensor to automatically adjustment the LCD brightness without losing the keyboard backlight adjustment due to surrounding state?

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There is currently no automatic method that I am aware of built into Ubuntu. However, take a look at lightum

It works fine on my mac but I have my lgiht senser in /sys/devices/platform/applesmc.768/light

You can check out the code and make the modifications or use it to write your own app.

The principal is sound, and I have seen other scripts do the same thing. If you don't want to tackle lightum try this or take a look at this mac info.

I know you have a sony but the process should be the same, read the sensor, set some values to a file in /sys/

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i go to /sys/devices/platform/ and can't find the file 'light' there is a folder called Sony-laptop but i can't find where it is ?? – amrelghobary Nov 10 '12 at 9:21
Try /sys/class/backlight/sony/brightness Of course knowing your exact model would help a lot. – coteyr Nov 10 '12 at 15:05
found this googling, it's a bit old, but it's a start. – coteyr Nov 10 '12 at 15:06
there is two folder in that path : "acpi_video0" and "acpi_video1" >>> my model is VPCF236FM – amrelghobary Nov 10 '12 at 16:16
cat /sys/class/backlight/acpi_video0/brightness – coteyr Nov 10 '12 at 17:38

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