the brightness is not available on this UMPC
Please attach the output of acpidump on this box.
Created attachment 24258 [details]
This is my output of acpidump
There is no ACPI backlight control methods available on this UMPC.
so this is not an ACPI bug.
what graphics are you using?
please attach the lspci output.
Created attachment 24263 [details]
It has a 915GM intel graphic. Is it possible to have in the future release of Kernel Linux same method for backlight?
This is lspci.
No. this is done is the BIOS...
But in Windows i can change it
Please test with new 'samsung-laptop' kernel driver, with recent xf86-video-intel release, to see if backlight can work on your samsung.
Where can i find samsung-laptop kernel driver? i use xf86-video-intel v 2.9.1 on gentoo
It's not relate to xf86-video-intel. Check if gentoo kernel already has 'samsung-laptop' module (e.g modprobe samsung-laptop), if not you have to build kernel with staging driver and make sure CONFIG_SAMSUNG_LAPTOP is on.
I checked in my .config of kernel 2.6.32, but there isn't CONFIG_SAMSUNG_LAPTOP. samsung-laptop.c miss in drivers/platform/x86/
It's under drivers/staging/samsung-laptop/
ok, i compiled kernel 2.6.33-rc2 with samsung laptop driver (on 2.6.32 this driver not exist), but backlight still not works
The samsung-laptop driver does not support this device, sorry.
It will not work with the dri driver, a special bios-mode call needs
to be made.
Patches are gladly accepted to add support for this device to the samsung-laptop driver, but I can not create them, myself.
Does http://patchwork.kernel.org/patch/81187/ help?
Another backlight dupe: https://bugs.freedesktop.org/show_bug.cgi?id=26664