Comment 12 for bug 912387

Created attachment 55714
drm-dmesg.txt

I added "drm.debug=0xe" to my kernel command line by hand, and got the following output.

This is not exactly the scenario described above -- I actually booted up at home away from my dock, suspended the laptop, came to work, and resumed in the dock. I had exactly the same situation that my external monitor wouldn't light up though, and I went through my (now-standard) workaround dance of:
 - log into text kernel and do xrandr --output LVDS1 --auto to turn on the laptop screen
 - light up the DP monitor at 1024x768
 - switch the DP monitor to 2560x1440 at the same time as I turn off the laptop screen

and I now have my X session working at native resolution on my external monitor.