monitor - Fedora 22 - unable adjust screen brightness -

my laptops msi ge60 2qd apache, use dual boot install fedora 22 beta , yum upgrade already, still can't adjust screen brightness. have no problem adjust brightness on window 8.

following output of xrandr:

[kelvin@apache ~]$ xrandr --verbose xrandr: failed size of gamma output default screen 0: minimum 1920 x 1080, current 1920 x 1080, maximum 1920 x 1080 default connected primary 1920x1080+0+0 (0x181) normal (normal) 0mm x 0mm         identifier: 0x180         timestamp:  88929         subpixel:   unknown         clones:             crtc:       0         crtcs:      0         transform:  1.000000 0.000000 0.000000                     0.000000 1.000000 0.000000                     0.000000 0.000000 1.000000                    filter:          _mutter_presentation_output: 0    1920x1080 (0x181) 159.667mhz *current         h: width  1920 start    0 end    0 total 1920 skew    0 clock  83.16khz         v: height 1080 start    0 end    0 total 1080           clock  77.00hz [kelvin@apache ~]$  

no difference if use xbacklight set different value:

[kelvin@apache ~]$ xbacklight -set 10 [kelvin@apache ~]$ xbacklight -set 0 [kelvin@apache ~]$ xbacklight -set 100 [kelvin@apache ~]$  

i tried xrandr can't set output because can't name xrandr output above:

[kelvin@apache ~]$ xrandr --brightness 0.7 xrandr: --brightness must used after --output try 'xrandr --help' more information. 

[kelvin@apache ~]$

this screenshot of gnome panel(my laptop not support wayland): http://i58.tinypic.com/av6gyu.png (i don't have enough reputation upload image)

as can see, there's volume control no brightness control.

any appreciated,

you need use:

xrandr --listactivemonitors 

to see active monitor(s) case:

monitors: 3  0: +*edp1 1366/340x768/190+0+0  edp1  1: +dp1 1920/520x1080/290+1366+0  dp1  2: +hdmi1 1920/520x1080/290+3286+0  hdmi1 

after need use:

xrandr --output <monitor> --brightness <value> 

for change screen brightness.