Same issue for my A8-450M laptop with Integrated or Discrete GPU set. I made some tests from kernel 3.8.0 to 3.12-RC6 on Ubuntu. I got same result with other distro like ArchLinux or Fedora.
# lspci 00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1 fh) Processor Root Complex 00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Trinit y [Radeon HD 7640G] Some other tests on my main kernel 3.11.6 (Ubuntu PPA) (CPU and GPU firmware has been updated to latest version) - After suspend and resume, with ssh I can check brightness control on /sys/class/blacklight/radeon_bl0/brightness and change the value but nothing change on screen (always black screen) - no syslog entry give information on the problem - no more information with drm.debug on kernel - fglrx doesn't have the same problem, suspend and resume work fine (but fglrx don't allow to change brightness). So, this concern seems to come from the drm driver and not from kernel or acpi, but I don't have enough knowledge to go further to identify the root cause in xorg -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1034002 Title: Lenovo E525 screen black on resume Status in Direct Rendering Infrastructure: Confirmed Status in The Linux Kernel: Fix Released Status in “linux” package in Ubuntu: Triaged Bug description: I did the kernel smoke test for the quantal kernel on precise. I can suspend and resume however when I resume I the screen stays black. It looks like the backlight isn't coming on, but it's noteable that I don't see anything on my external screen either. I can see consoles on my external monitor (over HDMI) and if I disconnect the HDMI cable and reconnect it then I am also able to see my Unity session on that screen. This issue is present with both the quantal kernel and the stock 12.04 one. My setup is a Lenovo Thinkpad E525, AMD A8-3500m. --- AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.25. ApportVersion: 2.0.1-0ubuntu12 Architecture: amd64 ArecordDevices: **** List of CAPTURE Hardware Devices **** card 1: Generic_1 [HD-Audio Generic], device 0: CONEXANT Analog [CONEXANT Analog] Subdevices: 1/1 Subdevice #0: subdevice #0 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC1: tealeg 2861 F.... pulseaudio /dev/snd/controlC0: tealeg 2861 F.... pulseaudio Card0.Amixer.info: Card hw:0 'Generic'/'HD-Audio Generic at 0xf0b44000 irq 48' Mixer name : 'ATI R6xx HDMI' Components : 'HDA:1002aa01,00aa0100,00100200' Controls : 6 Simple ctrls : 1 Card0.Amixer.values: Simple mixer control 'IEC958',0 Capabilities: pswitch pswitch-joined penum Playback channels: Mono Mono: Playback [on] Card1.Amixer.info: Card hw:1 'Generic_1'/'HD-Audio Generic at 0xf0b40000 irq 16' Mixer name : 'Conexant CX20590' Components : 'HDA:14f1506e,17aa21ea,00100002' Controls : 18 Simple ctrls : 10 Card29.Amixer.info: Card hw:29 'ThinkPadEC'/'ThinkPad Console Audio Control at EC reg 0x30, fw unknown' Mixer name : 'ThinkPad EC (unknown)' Components : '' Controls : 1 Simple ctrls : 1 Card29.Amixer.values: Simple mixer control 'Console',0 Capabilities: pswitch pswitch-joined penum Playback channels: Mono Mono: Playback [on] DistroRelease: Ubuntu 12.04 HibernationDevice: # RESUME=/dev/sda5 RESUME='UUID=61453936-e394-41de-8b00-5ee8f17023b3' InstallationMedia: Ubuntu-Server 12.04 LTS "Precise Pangolin" - Alpha amd64 (20111129) MachineType: LENOVO 12002KG Package: linux 3.2.0.27.29 PackageArchitecture: amd64 ProcEnviron: LANGUAGE=en_GB:en TERM=xterm PATH=(custom, user) LANG=en_GB.UTF-8 SHELL=/bin/bash ProcFB: 0 radeondrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.5.0-7-generic root=UUID=c2742c1e-158f-446d-9884-d6f037d7fa8c ro quiet splash elevator=deadline ProcVersionSignature: Ubuntu 3.5.0-7.7~precise1-generic 3.5.0 RelatedPackageVersions: linux-restricted-modules-3.5.0-7-generic N/A linux-backports-modules-3.5.0-7-generic N/A linux-firmware 1.79 Tags: precise running-unity Uname: Linux 3.5.0-7-generic x86_64 UpgradeStatus: No upgrade log present (probably fresh install) UserGroups: adm cdrom dip kvm libvirtd lpadmin plugdev sambashare sudo WifiSyslog: dmi.bios.date: 07/28/2011 dmi.bios.vendor: LENOVO dmi.bios.version: 8IET34WW(1.07) dmi.board.asset.tag: Not Available dmi.board.name: 12002KG dmi.board.vendor: LENOVO dmi.board.version: Not Available dmi.chassis.asset.tag: No Asset Information dmi.chassis.type: 10 dmi.chassis.vendor: LENOVO dmi.chassis.version: Not Available dmi.modalias: dmi:bvnLENOVO:bvr8IET34WW(1.07):bd07/28/2011:svnLENOVO:pn12002KG:pvrThinkPadE525:rvnLENOVO:rn12002KG:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable: dmi.product.name: 12002KG dmi.product.version: ThinkPad E525 dmi.sys.vendor: LENOVO To manage notifications about this bug go to: https://bugs.launchpad.net/dri/+bug/1034002/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp