Hi, thanks for your quick response. Am 06.11.2014 um 10:39 schrieb Jani Nikula: > On Thu, 06 Nov 2014, Arnd Hannemann <arnd@xxxxxxxxxx> wrote: >> Hi, >> >> I have a Thinkpad T440s (Haswell) connected to two additional Monitors >> via a Docking Station (MST). >> >> During Bootup all three displays work, even when X is started. >> However, if the laptop display is turned off once (either because of >> power saving, or via xrandr), it fails to "come back". >> That is if I try to re-enable it the Display stays blank. >> I believe this used to work in 3.17. >> >> Here is the xrandr Ouput of the edp, when its enabled (but staying blank): >> Screen 0: minimum 8 x 8, current 3840 x 1200, maximum 32767 x 32767 >> eDP1 connected 1920x1080+0+0 (normal left inverted right x axis y axis) 309mm x 175mm >> 1920x1080 60.0*+ 59.9 >> >> here is the debug output, while trying to enable it: >> > > ... > >> [ 416.538848] [drm:intel_edp_backlight_power] panel power control backlight disable >> >> >> I'm happy to provide further input. > > What does cat /sys/class/backlight/intel_backlight/bl_power say? What if root@kallisto:~# cat /sys/class/backlight/intel_backlight/bl_power 1 > you echo 0 there? :-) Works my display comes back, when I echo 0 there. Is user-space doing something wrong here? Best regards Arnd _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
