Public bug reported: After upgrading LTS kernel and X server from 12.04 to 12.04.03, my external monitor is no longer detected/driven. This worked perfectly under 12.04, and is therefore a major regression impacting common use cases. Does not affect the Display Port to DVI-D connection with the same display.
When the Display Port/VGA adapter is plugged in dmesg reports several: [drm:intel_dp_i2c_aux_ch] *ERROR* too many retries, giving up When booting with the VGA adaptor connected, dmesg is flooded with these and the trackpad does not work. I'm an experienced user but new to filing bugs. Feel free to ask for more information. Work arounds: Boot using 12.04 kernel (vmlinuz-3.2.0-54-generic) caveat: VGA works as 1024x768 or 800x600 out of the box but you dont need to know/find/add modlines. or Add the modline manually and enable using xrandr. This is less reliable, only works sometimes in my experience and the external monitor has some weird behaviour - no background and right click on the background appears only the primary display. //copy the modline from HDMI1 (DVI-D label in xrandr) to DP1 (or manually create the modline for your display): xrandr --addmode DP1 1920x1080 //connect the DP to VGA cable, removing the DP to DVI, run: xrandr --output DP1 --above eDP1 --mode 1920x1080 Hardware: MacBook Air 5,2 Mid 2012 Display configuration: Apple Display Port to VGA adaptor Ubuntu version: 12.04.3 with linux-lts-raring xserver-xorg-lts-raring xserver-xorg-video-intel-lts-raring. ProblemType: Bug DistroRelease: Ubuntu 12.04 Package: linux-image-3.8.0-31-generic 3.8.0-31.46~precise1 ProcVersionSignature: Ubuntu 3.8.0-31.46~precise1-generic 3.8.13.8 Uname: Linux 3.8.0-31-generic x86_64 NonfreeKernelModules: wl AlsaVersion: Advanced Linux Sound Architecture Driver Version k3.8.0-31-generic. ApportVersion: 2.0.1-0ubuntu17.5 Architecture: amd64 ArecordDevices: **** List of CAPTURE Hardware Devices **** card 0: PCH [HDA Intel PCH], device 0: Cirrus Analog [Cirrus Analog] Subdevices: 1/1 Subdevice #0: subdevice #0 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: shah 2374 F.... pulseaudio Card0.Amixer.info: Card hw:0 'PCH'/'HDA Intel PCH at 0xa0610000 irq 23' Mixer name : 'Intel PantherPoint HDMI' Components : 'HDA:10134206,106b5600,00100302 HDA:80862806,80860101,00100000' Controls : 37 Simple ctrls : 10 Date: Sat Oct 19 11:34:54 2013 HibernationDevice: RESUME=UUID=363970cc-f00e-4fc5-9ad4-85835761f881 InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120823.1) MachineType: Apple Inc. MacBookAir5,2 MarkForUpload: True ProcFB: 0 inteldrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.8.0-31-generic root=UUID=546e99ab-1217-4a80-9242-a78138929e8f ro crashkernel=384M-2G:64M,2G-:128M quiet i915.i915_enable_rc6=1 resume=/dev/sda6 noapic RelatedPackageVersions: linux-restricted-modules-3.8.0-31-generic N/A linux-backports-modules-3.8.0-31-generic N/A linux-firmware 1.79.7 SourcePackage: linux-lts-raring UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 11/27/2012 dmi.bios.vendor: Apple Inc. dmi.bios.version: MBA51.88Z.00EF.B02.1211271028 dmi.board.asset.tag: Base Board Asset Tag# dmi.board.name: Mac-2E6FAB96566FE58C dmi.board.vendor: Apple Inc. dmi.board.version: MacBookAir5,2 dmi.chassis.type: 10 dmi.chassis.vendor: Apple Inc. dmi.chassis.version: Mac-2E6FAB96566FE58C dmi.modalias: dmi:bvnAppleInc.:bvrMBA51.88Z.00EF.B02.1211271028:bd11/27/2012:svnAppleInc.:pnMacBookAir5,2:pvr1.0:rvnAppleInc.:rnMac-2E6FAB96566FE58C:rvrMacBookAir5,2:cvnAppleInc.:ct10:cvrMac-2E6FAB96566FE58C: dmi.product.name: MacBookAir5,2 dmi.product.version: 1.0 dmi.sys.vendor: Apple Inc. ** Affects: linux-lts-raring (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug linux-lts-raring precise qa-kernel-lts-testing xserver-xorg-lts-raring xserver-xorg-video-intel-lts-raring -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1242013 Title: [Macbook Air 5,2] External monitor not working 12.04 - Display Port to VGA, xserver-xorg-lts-raring, Intel HD 4000 graphics To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-lts-raring/+bug/1242013/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs