Re: [Intel-gfx] Regression: Backlight not coming on after resume.
On Thu, 28 Feb 2013, James Courtier-Dutton wrote: > Bisect done on tree: > git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git > Worked on 3.7. > Broken on 3.8 > > Problem: "Backlight not coming on after resume." > git finally bisected for my Samsung Serial 7 Laptop. > Bisecting: 0 revisions left to test after this (roughly 0 steps) > [cf0a6584aa6d382f802f2c3cacac23ccbccde0cd] drm/i915: write backlight > harder <- This is the problem commit. Seems that fixing some > machines breaks others, based on the existing comments on that patch. The backlight haunts us again. Could you post the dmesg with drm.debug=0xe module parameter, first running vanilla 3.8, and then with the bad commit reverted, please? Might not be a bad idea to file a bug on Product=DRI, Component=DRM/Intel at https://bugs.freedesktop.org (see https://01.org/linuxgraphics/documentation/how-report-bugs-0 for details) and attach your bisect results and the dmesgs there. Thanks, Jani. ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] Regression: Backlight not coming on after resume.
At Thu, 28 Feb 2013 17:33:56 +0200, Jani Nikula wrote: > > On Thu, 28 Feb 2013, James Courtier-Dutton wrote: > > Bisect done on tree: > > git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git > > Worked on 3.7. > > Broken on 3.8 > > > > Problem: "Backlight not coming on after resume." > > git finally bisected for my Samsung Serial 7 Laptop. > > Bisecting: 0 revisions left to test after this (roughly 0 steps) > > [cf0a6584aa6d382f802f2c3cacac23ccbccde0cd] drm/i915: write backlight > > harder <- This is the problem commit. Seems that fixing some > > machines breaks others, based on the existing comments on that patch. > > The backlight haunts us again. Could you post the dmesg with > drm.debug=0xe module parameter, first running vanilla 3.8, and then with > the bad commit reverted, please? > > Might not be a bad idea to file a bug on Product=DRI, > Component=DRM/Intel at https://bugs.freedesktop.org (see > https://01.org/linuxgraphics/documentation/how-report-bugs-0 for > details) and attach your bisect results and the dmesgs there. I'm afraid the patch doesn't do it right. It fixes for Dell, but the old problem on others back by that. It was merged before actually testing on the machines the original fix was intended for. Now I can confirm a problem (partially) with the latest Linus tree on a new laptop. I write "partially" because it happens only during the splash screen of S4 hibernation, so I've ignored, so far. James, try to revert that commit. Does it fix? If so, you should check the output of intel_reg_dumper at broken and working states. Takashi ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] Regression: Backlight not coming on after resume.
On Feb 28, 2013 5:20 PM, "Takashi Iwai" wrote: > > At Thu, 28 Feb 2013 17:33:56 +0200, > Jani Nikula wrote: > > > > On Thu, 28 Feb 2013, James Courtier-Dutton wrote: > > > Bisect done on tree: > > > git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git > > > Worked on 3.7. > > > Broken on 3.8 > > > > > > Problem: "Backlight not coming on after resume." > > > git finally bisected for my Samsung Serial 7 Laptop. > > > Bisecting: 0 revisions left to test after this (roughly 0 steps) > > > [cf0a6584aa6d382f802f2c3cacac23ccbccde0cd] drm/i915: write backlight > > > harder <- This is the problem commit. Seems that fixing some > > > machines breaks others, based on the existing comments on that patch. > > > > The backlight haunts us again. Could you post the dmesg with > > drm.debug=0xe module parameter, first running vanilla 3.8, and then with > > the bad commit reverted, please? > > > > Might not be a bad idea to file a bug on Product=DRI, > > Component=DRM/Intel at https://bugs.freedesktop.org (see > > https://01.org/linuxgraphics/documentation/how-report-bugs-0 for > > details) and attach your bisect results and the dmesgs there. > > I'm afraid the patch doesn't do it right. It fixes for Dell, but the > old problem on others back by that. It was merged before actually > testing on the machines the original fix was intended for. > > Now I can confirm a problem (partially) with the latest Linus tree on > a new laptop. I write "partially" because it happens only during the > splash screen of S4 hibernation, so I've ignored, so far. > > James, try to revert that commit. Does it fix? > > If so, you should check the output of intel_reg_dumper at broken and > working states. > Can someone point me to a datasheet that relates to this bit of code, so i can understand what all the registers do. I would like to understand the code in order to suggest a better fix. ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
Re: [Intel-gfx] Regression: Backlight not coming on after resume.
Hi James - On Fri, 01 Mar 2013, James Courtier-Dutton wrote: >> James, try to revert that commit. Does it fix? >> >> If so, you should check the output of intel_reg_dumper at broken and >> working states. >> > Can someone point me to a datasheet that relates to this bit of code, so i > can understand what all the registers do. > I would like to understand the code in order to suggest a better fix. https://01.org/linuxgraphics/documentation/driver-documentation-prms Vol 3 is the relevant volume in each generation. I don't think any of the docs back up the comments in the bad commit saying "BLC_PWM_CPU_CTL is cleared to zero automatically when BLC_PWM_CPU_CTL2 and BLC_PWM_PCH_CTL1 are written" though. I guess it could be some bad ACPI/BIOS interaction too. I'd still urge you to file the bug, and attach the dmesgs and register dumps first. And let us know if the revert fixes it. BR, Jani. ___ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
