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|Summary:||backlight problem with Intel i915 integrated graphics adatper in N4xx/N5xx Atom after kernel 3.14.2|
|Product:||[Fedora] Fedora||Reporter:||Paul DeStefano <paul.destefano-redhat2>|
|Component:||kernel||Assignee:||Hans de Goede <hdegoede>|
|Status:||CLOSED ERRATA||QA Contact:||Fedora Extras Quality Assurance <extras-qa>|
|Version:||21||CC:||gansalmon, hdegoede, itamar, jonathan, kernel-maint, madhu.chinakonda, mchehab, paul.destefano-redhat2|
|Fixed In Version:||kernel-3.18.3-201.fc21||Doc Type:||Bug Fix|
|Doc Text:||Story Points:||---|
|Last Closed:||2015-01-26 02:31:04 UTC||Type:||Bug|
|oVirt Team:||---||RHEL 7.3 requirements from Atomic Host:|
|Cloudforms Team:||---||Target Upstream Version:|
Description Paul DeStefano 2014-07-02 21:22:20 UTC
Description of problem: After update to kernel 3.14.2, backlight adjustment via fn-key combination doesn't work. Furthermore, 3.14.7 does not fix the problem. lspci -vv: ... VGA compatible controller: Intel Corporation Atom Processor D4xx/D5xx/N4xx/N5xx Integrated Graphics Controller ... Kernel driver in use: i915 ... Version-Release number of selected component (if applicable): 3.14.2-200 How reproducible: Since 3.14.2 Steps to Reproduce: 1. Update to kernel v3.14.2 or later, 2. 3. Actual results: Backlight adjustment from X session is broken, cannot adjust. Expected results: Should behave as v3.14.1 or earlier. Additional info: This bug is nearly identical to bug 1093991, but isn't since problem persists after bug was fixed.
Comment 1 Justin M. Forbes 2014-11-13 16:01:46 UTC
*********** MASS BUG UPDATE ************** We apologize for the inconvenience. There is a large number of bugs to go through and several of them have gone stale. Due to this, we are doing a mass bug update across all of the Fedora 20 kernel bugs. Fedora 20 has now been rebased to 3.17.2-200.fc20. Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel. If you have moved on to Fedora 21, and are still experiencing this issue, please change the version to Fedora 21. If you experience different issues, please open a new bug report for those.
Comment 2 Paul DeStefano 2014-11-15 23:30:07 UTC
Problem is still present with latest kernel v3.17.2. Just to remind you, the problem and symptoms are identical to bug 1093991. 'backlight' shows FN-keys are changing the backlight setting, but backlight is not actually adjusted. And the workaround for X11 is still required: Section "Device" Identifier "Intel Graphics" Driver "intel" Option "AccelMethod" "sna" Option "Backlight" "intel_backlight" # use your backlight that works here BusID "PCI:0:2:0" EndSection
Comment 3 Hans de Goede 2014-11-25 13:30:47 UTC
Hi Paul, (In reply to Paul DeStefano from comment #2) > Problem is still present with latest kernel v3.17.2. > > Just to remind you, the problem and symptoms are identical to bug 1093991. > 'backlight' shows FN-keys are changing the backlight setting, but backlight > is not actually adjusted. And the workaround for X11 is still required: > > Section "Device" > Identifier "Intel Graphics" > Driver "intel" > Option "AccelMethod" "sna" > Option "Backlight" "intel_backlight" # use your backlight > that works here > BusID "PCI:0:2:0" > EndSection So with this workaround things do work ? Can you please do "sudo dmidecode > dmi.log" and attach the generated dmi.log file here ? Regards, Hans
Comment 4 Paul DeStefano 2014-12-11 21:54:00 UTC
Confirmed on F21. But, let me try your request, now; just saw it.
Comment 6 Hans de Goede 2014-12-12 11:51:54 UTC
Hi Paul, Thanks for the info, 2 questions: 1) Can you please do: "ls /sys/class/backlight" In a terminal and copy & paste the output here ? 2) Can you please confirm that things do work properly with the workaround from comment #2 ? Thanks, Hans
Comment 7 Paul DeStefano 2014-12-14 08:05:35 UTC
(In reply to Hans de Goede from comment #6) > 1) Can you please do: > > "ls /sys/class/backlight" Sure, you bet... > ls -ltr /sys/class/backlight/ total 0 lrwxrwxrwx. 1 root root 0 Dec 13 15:53 intel_backlight -> ../../devices/pci0000:00/0000:00:02.0/drm/card0/card0-LVDS-1/intel_backlight/ lrwxrwxrwx. 1 root root 0 Dec 13 23:53 samsung -> ../../devices/platform/samsung/backlight/samsung/ > 2) Can you please confirm that things do work properly with the workaround > from comment #2 ? Yes, I'm still using the same file contents shown in comment #2 as a workaround. FWIW, the on-screen overlay backlight adjustment indicator is missing in F21, but that could be an issue with my desktop. If F20, there was a horizontal percentage bar that would show for a few seconds while changing the brightness; that's gone now and no brightness indication is shown while adjusting. If you could tell me whether that's part of this bug or not, that'd be helpful. But, asside from the indicator bar, the backlight adjustment *does work* with the aforementioned workaround, and doesn't work without the workaround.
Comment 8 Hans de Goede 2015-01-09 15:54:00 UTC
Hi, I've done a kernel scratch-build, with a fix for this, please give it a try. Please download the following rpms: kernel-3.17.8-...rpm kernel-core-3.17.8-...rpm kernel-modules-3.17.8-...rpm For your arch from here: http://koji.fedoraproject.org/koji/taskinfo?taskID=8571559 (note this is still building atm) Save them all to the same directory (which should not contain other rpms) and do: sudo rpm -ivh kernel-*.rpm From within that directory. Then mv the custom xorg.conf file to somewhere where xorg will not find it, boot into the new kernel check if the backlight works as expected. Regards, Hans
Comment 9 Paul DeStefano 2015-01-10 08:05:08 UTC
Success! Yes, that works. FWIW, backlight is 100% now at boot on battery, which is different than it was before. But, fn-keys adjust backlight as expected with your kernel build. Should I uninstall these packages, now?
Comment 10 Hans de Goede 2015-01-10 08:54:34 UTC
(In reply to Paul DeStefano from comment #9) > Success! Yes, that works. > > FWIW, backlight is 100% now at boot on battery, which is different than it > was before. But, fn-keys adjust backlight as expected with your kernel > build. That is likely only the case the first boot because the backlight device in use changed, systemd should remember your backlight level over reboots, so once you reboot from the new kernel to the new kernel you should get your last used backlight level. > Should I uninstall these packages, now? There is no reason to uninstall them really. Once I've confirmation for the fixes in question for a number of related bugs I'll ask the kernel team to add the fixes to the official Fedora kernel builds.
Comment 11 Josh Boyer 2015-01-12 14:15:22 UTC
Patch added to Fedora git. Thanks Hans!
Comment 12 Fedora Update System 2015-01-14 13:14:36 UTC
kernel-3.18.2-200.fc21 has been submitted as an update for Fedora 21. https://admin.fedoraproject.org/updates/kernel-3.18.2-200.fc21
Comment 13 Fedora Update System 2015-01-14 23:59:55 UTC
Package kernel-3.18.2-200.fc21: * should fix your issue, * was pushed to the Fedora 21 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing kernel-3.18.2-200.fc21' as soon as you are able to, then reboot. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2015-0724/kernel-3.18.2-200.fc21 then log in and leave karma (feedback).
Comment 14 Fedora Update System 2015-01-19 20:49:17 UTC
kernel-3.18.3-201.fc21 has been submitted as an update for Fedora 21. https://admin.fedoraproject.org/updates/kernel-3.18.3-201.fc21
Comment 15 Fedora Update System 2015-01-26 02:31:04 UTC
kernel-3.18.3-201.fc21 has been pushed to the Fedora 21 stable repository. If problems still persist, please make note of it in this bug report.