2012/5/22 Zdenek Kabelac <zdenek.kabelac at gmail.com>: > 2012/5/22 Daniel Vetter <daniel at ffwll.ch>: >> On Tue, May 22, 2012 at 04:36:30PM +0200, Zdenek Kabelac wrote: >>> 2012/5/22 Daniel Vetter <daniel at ffwll.ch>: >>> > On Tue, May 22, 2012 at 02:08:46PM +0200, Zdenek Kabelac wrote: >>> >> Hi >>> >> >>> >> I've updated to 3.4 kernel, and now I'm noticing slight changes in >>> >> brightness on colorful images. >>> >> It seems the change is mostly visibly on ?'darker' images i.e. it's >>> >> not really visible on white background. >>> >> >>> >> When I reboot back to 3.3 ?kernel - brightness changes are gone - so I >>> >> do not suspect hw fault of my T61 display. >>> >> I guess once in past there has been already such bug, so this problem >>> >> seems to me like reintroducing the same >>> >> problem again. >>> >> >>> >> xorg-x11-server-Xorg-1.12.1-1.fc18.x86_64 >>> >> with SNA intel driver build from git repo. >>> >> T61, 965GM >>> >> >>> >> Is this a know issue ? >>> >> Is bisect needed ? >>> > >>> > You're the first one to report things, so a bisect would be highly >>> > appreciated. Also I'm a bit confused about what you mean by 'changing >>> > brightness'. Can you please try to explain this a bit more? >>> > >>> >>> I've some default gnome picture like this one: >>> https://lh6.googleusercontent.com/-96ZhFbfLX_M/ThHsm0ZxBgI/AAAAAAAAFQQ/3ApjzYgulso/s400/gnome-3-login-screen.png >>> >>> When I watch the picture for some period of time ?I'm noticing slight >>> changes in the picture brightness looking like small change in LUT >>> table or something like that. >>> If the picture is white I'm not noticing any change. >>> (Initially I've thought my display dies - but reboot to 3.3 fixed the >>> issue immediately). >> >> "for some period", does that mean it takes you a while to notice the >> changes (because they're tiny), or are the changes happend just rather slowly? >> > > Deviation in picture is not huge - but gets noticeable by my eyes and > it's annoying, > it's like several seconds between each minor change. > > If I've monotone background in i.e. text editor ?the change is > practically not visibible, > but if watch some digicam photos full screen they are quite obvious. > > Not sure if that has any influence (not tested without) ?I'm using > some icc profile > ('xcalib') to get away from blue of IBM display. > >>> Is there any suspecting patch for this chipset I should try to revert ? >> >> Tbh I have no idea. If there's no changes when the picture is white, it >> can't be the backlight, we haven't frobbed around with the gamma stuff and >> temporal dithering is disabled, too. If you can bisect this it would >> greatly help. > > ok, I'll play this game in the evening if there is nothing obvious. > And we have a winner - cec2f356d59d9e070413e5966a3c5a1af136d948 drm/i915: Only look for matching clocks for LVDS downclock reverting just this patch for vanilla 3.4 fixes the problem for my T61. (I've not tried to play with those individial 3 pieces inside this patch to check exactly which one is responsible) Zdenek Here is the bisect game: git bisect start # bad: [acc73fb11695b564dc485b1f98f8237bbdc0742f] Remove ioctl warning git bisect bad acc73fb11695b564dc485b1f98f8237bbdc0742f # good: [c16fa4f2ad19908a47c63d8fa436a1178438c7e7] Linux 3.3 git bisect good c16fa4f2ad19908a47c63d8fa436a1178438c7e7 # bad: [141124c02059eee9dbc5c86ea797b1ca888e77f7] Delete all instances of asm/system.h git bisect bad 141124c02059eee9dbc5c86ea797b1ca888e77f7 # good: [3b59bf081622b6446db77ad06c93fe23677bc533] Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next git bisect good 3b59bf081622b6446db77ad06c93fe23677bc533 # good: [424a6f6ef990b7e9f56f6627bfc6c46b493faeb4] Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6 git bisect good 424a6f6ef990b7e9f56f6627bfc6c46b493faeb4 # bad: [be53bfdb8088e9d1924199cc1a96e113756b1075] Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux git bisect bad be53bfdb8088e9d1924199cc1a96e113756b1075 # good: [828006de1bddf83b6ecf03ec459c15f7c7c22db7] Merge tag 'asoc-3.4' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into topic/asoc git bisect good 828006de1bddf83b6ecf03ec459c15f7c7c22db7 # skip: [496a73bbecb81e6753715995e4519d152f814667] drm/nv50/pm: use hwsq for engine reclocking too git bisect skip 496a73bbecb81e6753715995e4519d152f814667 # skip: [c11dd0da5277596d0ccdccb745b273d69a94f2d7] drm/nouveau/pm: fix oops if chipset has no pm support at all git bisect skip c11dd0da5277596d0ccdccb745b273d69a94f2d7 # skip: [07cafff288266c3aa082f4bda3d47989e73ee85d] ALSA: hda/conexant - Clear unsol events on unused pins git bisect skip 07cafff288266c3aa082f4bda3d47989e73ee85d # bad: [f3298532f71f163877b9003009d6e1eefe988258] drm/nvc0: add initial memory type detection git bisect bad f3298532f71f163877b9003009d6e1eefe988258 # bad: [019d96cb55ade38a4b4a52bba0304e8cd681f30a] drm: add some caps for userspace to discover more info for dumb KMS driver (v2) git bisect bad 019d96cb55ade38a4b4a52bba0304e8cd681f30a # bad: [5c0480f21f9896c443b0e65d779c8e09a695da7b] drm/i915: fall through pwrite_gtt_slow to the shmem slow path git bisect bad 5c0480f21f9896c443b0e65d779c8e09a695da7b # bad: [8e636784b6f76653d358d521af9c2a8c246df38b] drm/i915: fixup assert_pipe to take the pipe A quirk into account git bisect bad 8e636784b6f76653d358d521af9c2a8c246df38b # bad: [23c99e775d14f01ba45a5affd2fb51af4328359c] drm/i915: Fix assert_pch_hdmi_disabled to mention HDMI (not DP) git bisect bad 23c99e775d14f01ba45a5affd2fb51af4328359c # bad: [a7516a05311d0e2deb8ce8ae8b8c12a513ca8ca2] drm/i915: split out pll divider code git bisect bad a7516a05311d0e2deb8ce8ae8b8c12a513ca8ca2 # bad: [5a117db77e47e3946d1aaa7ce8deafafd9d76746] drm/i915: there is no pipe CxSR on ironlake git bisect bad 5a117db77e47e3946d1aaa7ce8deafafd9d76746 # good: [0b8ecdda1943a05c8e7896f0b5f1addf39269927] drm/i915: Silence _DSM errors git bisect good 0b8ecdda1943a05c8e7896f0b5f1addf39269927
