On 26 May 2014 13:18, Lewis Toohey <lewis@xxxxxxxxxxxx> wrote: > On 26 May 2014 06:48, Aaron Lu <aaron.lu@xxxxxxxxx> wrote: >> On 05/26/2014 04:42 AM, Lewis Toohey wrote: >>> On 23 May 2014 13:50, Hans de Goede <hdegoede@xxxxxxxxxx> wrote: >>>> Hi Lewis et all, >>>> >>>> On 05/23/2014 02:07 PM, Lewis Toohey wrote: >>>>> On 23 May 2014 02:34, Aaron Lu <aaron.lu@xxxxxxxxx> wrote: >>>>>> On 05/21/2014 09:02 PM, Lewis Toohey wrote: >>>>>>> Hi Aaron >>>>>>> >>>>>>> I followed your instructions and can report some limited success. I >>>>>>> have two interfaces listed in /sys/class/backlight namely: >>>>>>> acpi_video0 radeon_bl0 >>>>>>> >>>>>>> max_brightness for acpi_video0 is 11. Echo-ing new values to >>>>>>> brightness appears to have no effect. >>>>>>> >>>>>>> max_brightness for radeon_bl0 is 255. Echo-ing new values to >>>>>>> brightness does adjust the screen brightness as you would expect. >>>>>>> >>>>>>> Results are the same on both battery and powered. >>>>>>> >>>>>>> I hope that is useful. >>>>>> >>>>>> I think Hans' patchset should solve your problem, can you please give it >>>>>> a try? You will need to pass the video.use_native_backlight=1 to kernel >>>>>> cmdline when testing, thanks. >>>>>> >>>>>> [PATCH resend 0/4] Make video.use_native_backlight=1 work properly with nouveau >>>>>> http://www.spinics.net/lists/dri-devel/msg59941.html >>>>>> >>>>>> -Aaron >>>>> >>>>> Aaron >>>>> >>>>> Thank you for this. Unfortunately I am going to have to ask you for a >>>>> bit of help here as I am now, officially, "out of my depth". I >>>>> appreciate this is a pain as you will have to take time explaining it >>>>> to me and I apologise for that. >>>>> >>>>> I have figured out how to pass the kernel command line argument, this >>>>> is not an issue. >>>>> >>>>> I have located the patch you refer to here: >>>>> https://bugzilla.redhat.com/attachment.cgi?id=894577 >>>>> (which I believe is correct) but I cannot figure out how to apply it. >>>> >>>> That is not the right patch, you need a set of 2 patches. I've attached >>>> them to this mail. Note please ignore the numbering starting at 6, these >>>> are the 2 patches you need. You will need to build a Linux kernel with >>>> these 2 patches applied, see your distributions documentation on how >>>> to build a kernel from source. >>>> >>>> I don't know which distro you are using, I've a Fedora kernel with this >>>> patches included available here: >>>> >>>> http://people.fedoraproject.org/~jwrdegoede/rhbz1093171/ >>>> >>>> Regards, >>>> >>>> Hans >>> >>> Hans >>> >>> Unfortunately I am unable to apply these patches against the latest >>> mainline kernel. I get two fails when applying the second patch file >>> and then the kernel will not compile. Please see output information >>> below. >> >> I've prepared a git branch for you: >> https://github.com/aaronlu/linux.git for-lewis >> >> It's based on Rafael's linux-next plus Hans' patch 2 and 3. >> >> Thanks, >> Aaron >> >>> >>> Can you advise? >>> >>> Many thanks >>> >>> ===APPLYING PATCHES TO LATEST MAINLINE KERNEL==== >>> >>> lewis@HappyFunMeaowMeaow:~/KernelTesting/Kernel/linux$ patch -p1 < >>> 0006-backlight-Add-backlight-device-un-registration-notif.patch >>> (Stripping trailing CRs from patch; use --binary to disable.) >>> patching file drivers/video/backlight/backlight.c >>> (Stripping trailing CRs from patch; use --binary to disable.) >>> patching file include/linux/backlight.h >>> lewis@HappyFunMeaowMeaow:~/KernelTesting/Kernel/linux$ patch -p1 < >>> 0007-acpi-video-Unregister-the-backlight-device-if-a-raw-.patch >>> (Stripping trailing CRs from patch; use --binary to disable.) >>> patching file drivers/acpi/video.c >>> Hunk #1 FAILED at 151. >>> Hunk #2 succeeded at 161 (offset -1 lines). >>> Hunk #3 FAILED at 1837. >>> Hunk #4 succeeded at 1868 (offset -113 lines). >>> Hunk #5 succeeded at 1999 (offset -113 lines). >>> Hunk #6 succeeded at 2023 (offset -113 lines). >>> 2 out of 6 hunks FAILED -- saving rejects to file drivers/acpi/video.c.rej >>> >>> >>> ==LAST LINES OF BUILD BEFORE FAIL=== >>> >>> CC [M] fs/xfs/xfs_ioctl32.o >>> LD [M] fs/xfs/xfs.o >>> make[1]: Leaving directory `/home/lewis/KernelTesting/Kernel/linux' >>> make: *** [debian/stamp/build/kernel] Error 2 >>> lewis@HappyFunMeaowMeaow:~/KernelTesting/Kernel/linux$ >>> >>> >> > > Aaron > > Many thanks for this. I can confirm that booting with this kernel and > passing the video.use_native_backlight = 1 argument means that the > backlight works perfectly on my laptop (both using the keyboard hot > keys and the gnome/unity settings applet). > > I'll post to the ubuntu launchpad page later with instructions for > other people to do this. I assume its presence in the linux-next tree > means that it will be fixed in an upcoming kernel release? (sorry, I > don't know quite how the process works). > > If I can provide more information or do some more useful testing > please do not hesitate to let me know. > > Thank you both for your help - really appreciated. > > -- > Lewis > Aaron Just one final point in case it is relevant / useful - although it fixes the backlight issue this kernel version breaks the suspend resume functionality for me (the system will suspend but cannot come back from it). Not asking for a fix (appreciate it is a testing base), just thought it might be useful to know. Thanks again -- Lewis Lewis@xxxxxxxxxxxx 0782 588 4158 -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
