3 Replies Latest reply on May 27, 2016 8:34 AM by allan_intel

    Ubuntu 15.10 Intel-NUC video doesn't recover when input is switched

    ErnieE

      I purchased an Intel-NUC to hide behind a display (Dell U3014) that I typically use with a MacBook Pro (Runs Linux mostly, but dual boots Windows 7 Windows 10). The NUC is using a Mini-DP to DP connector and the MBP is using a DP to Mini-DP. (DisplayPort 1.2 support on the monitor is annoyingly turned off. I would love it if MST worked with Intel graphics ON LINUX, but that is another issue.)

       

      For the record I have the same issue with Ubuntu 15.04 or 14...

       

      Intel NUC Kit NUC5i7RYH

      (has dedicated Samsung 850 (M.2) for Kubuntu and dedicated Samsung 840 (SATA) for Windows)

       

      uname -a

      Linux erniee-nuc 4.2.0-16-generic #19-Ubuntu SMP Thu Oct 8 15:35:06 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

       

      lspci -s 02 -k  
      00:02.0 VGA compatible controller: Intel Corporation Broadwell-U Integrated Graphics (rev 09)
              Subsystem: Intel Corporation Device 2057
              Kernel driver in use: i915


      When I turn the display off, switch inputs, or otherwise lose the signal to the display the Linux driver/TTY7 will NOT recover.  This is beyond annoying if I have left things in a state that I need to work with.  Yeah, I also could run Linux in a VM on the MBP (and do) but that isn't the point. I can Ctrl+Alt+F1 (1-6) to use any of the other FB tty's, but haven't found a way to recover the display.


      Is there a solution to this? I really don't know who to 'blame', but I DO NOT have the same issue (on other systems, will ask related, but different questions about those) with the Intel drivers disabled and NVidia hosted displays under Ubuntu/Linux (sometimes Debian in the past).


      If I leave the system connected to the display at all times, then I don't have issues.