Nicolas Devillers, from my personal experience, regarding backlight bugs where one is forced to use acpi_backlight=vendor to enable it, these reports typically result in upstream making a quirk for the hardware in order to enable the backlight by default. Hence, the best strategy would be to get the quirk merged upstream, in turn pulled downstream and supported in Ubuntu, then refocus on how if the quirk still causes suspend to not work, refocus to this.
Hence, could you please open a new report via a terminal: ubuntu-bug linux and feel free to subscribe me to it. ** Changed in: linux (Ubuntu) Status: Incomplete => Confirmed -- 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/1214287 Title: [Dell Inspiron 15R 5521] suspend/resume failure Status in “linux” package in Ubuntu: Confirmed Bug description: Dell Inc. Inspiron 5521 often crash when resuming. WORKAROUND: Don't use non default kernel parameters: acpi_osi=Linux acpi_backlight=vendor ProblemType: KernelOops DistroRelease: Ubuntu 13.10 Package: linux-image-3.11.0-2-generic 3.11.0-2.5 ProcVersionSignature: Ubuntu 3.11.0-2.5-generic 3.11.0-rc5 Uname: Linux 3.11.0-2-generic x86_64 Annotation: This occured during a previous suspend and prevented it from resuming properly. ApportVersion: 2.12-0ubuntu3 Architecture: amd64 AudioDevicesInUse: USER PID ACCESS COMMAND /dev/snd/controlC0: nicolas 2763 F.... pulseaudio Date: Tue Aug 20 10:02:28 2013 ExecutablePath: /usr/share/apport/apportcheckresume Failure: suspend/resume HibernationDevice: RESUME=UUID=173db09c-bffc-4da9-ab42-7ca73f84e71f InstallationDate: Installed on 2013-04-08 (133 days ago) InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Release amd64 (20121017.5) InterpreterPath: /usr/bin/python3.3 MachineType: Dell Inc. Inspiron 5521 MarkForUpload: True ProcCmdline: /usr/bin/python3 /usr/share/apport/apportcheckresume ProcEnviron: TERM=linux PATH=(custom, no user) ProcFB: 0 inteldrmfb 1 radeondrmfb ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.11.0-2-generic root=UUID=09af3e13-8004-48fa-b0fe-116acbf8d3d7 ro crashkernel=384M-2G:64M,2G-:128M quiet splash acpi_osi=Linux acpi_backlight=vendor vt.handoff=7 PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: Daemon not responding. RelatedPackageVersions: linux-restricted-modules-3.11.0-2-generic N/A linux-backports-modules-3.11.0-2-generic N/A linux-firmware 1.113 SourcePackage: linux StagingDrivers: rts5139 Title: [Dell Inc. Inspiron 5521] suspend/resume failure UpgradeStatus: Upgraded to saucy on 2013-06-24 (56 days ago) UserGroups: dmi.bios.date: 05/20/2013 dmi.bios.vendor: Dell Inc. dmi.bios.version: A08 dmi.board.name: 0HK2KG dmi.board.vendor: Dell Inc. dmi.board.version: A00 dmi.chassis.type: 8 dmi.chassis.vendor: Dell Inc. dmi.chassis.version: A08 dmi.modalias: dmi:bvnDellInc.:bvrA08:bd05/20/2013:svnDellInc.:pnInspiron5521:pvrA08:rvnDellInc.:rn0HK2KG:rvrA00:cvnDellInc.:ct8:cvrA08: dmi.product.name: Inspiron 5521 dmi.product.version: A08 dmi.sys.vendor: Dell Inc. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1214287/+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