Laptop: Toshiba R630
http://www.linlap.com/toshiba_portege_r700-r705
OS: Mint 14, Cinnamon
$ lspci | grep -i vGA
00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 02)
Apart from the commonly reported problem of loss of brightness level, I cannot change my brightness at all once I recover from stand by. If I use 'brightness and lock' and try to move the slider, the brightness never change.
I have seen multiple threads related to the problem. I have tried a few suggested fixes but I could not get it to work. It looks like for an average linux user like me the solutions described are not much understandable.
Can someone explain or point to right documentation to understand the problem related to setting/modify display brightness?
1. xrandr
xrandr --output LVDS1 --brightness 0.8
this works but what i do not understand is when I bring the value below 1.0 (max brightness), the screen is not convenient to look at. I am unable to describe technically which constituent related to brightness is not correct.
2. acpi
echo 7 > /sys/class/backlight/acpi_video0/brightness
i tried this solution but it does not change brightness
3. toshset
$ toshset
required kernel toshiba support not enabled.
Not sure what to do with the above.
4. setpci
rag@rag-tos-laptop:~$ sudo lspci | grep VGA
00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 02)
$ setpci -s 00:02.0 F4.B=80
pcilib: Cannot open /sys/bus/pci/devices/0000:00:02.0/config
but something seems to be different for my laptop