Bug 32412 - [GM45] bad default gamma
Summary: [GM45] bad default gamma
Status: RESOLVED UNREPRODUCIBLE
Alias: None
Product: Drivers
Classification: Unclassified
Component: Video(DRI - Intel) (show other bugs)
Hardware: All Linux
: P1 normal
Assignee: drivers_video-dri-intel@kernel-bugs.osdl.org
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2011-03-31 23:37 UTC by Vitaly Minko
Modified: 2012-04-19 08:25 UTC (History)
3 users (show)

See Also:
Kernel Version: 2.6.36-gentoo-r5
Subsystem:
Regression: No
Bisected commit-id:

Attachments
photo demonstrating the issue (430.69 KB, image/jpeg)
2011-03-31 23:37 UTC, Vitaly Minko 		Details
original image (295.70 KB, image/jpeg)
2011-03-31 23:38 UTC, Vitaly Minko 		Details
kernel config (53.82 KB, application/octet-stream)
2011-03-31 23:39 UTC, Vitaly Minko 		Details
lspci -v (8.49 KB, text/x-log)
2011-03-31 23:39 UTC, Vitaly Minko 		Details
GRUB config (331 bytes, text/plain)
2011-03-31 23:40 UTC, Vitaly Minko 		Details
the same image displayed via vesafb (602.94 KB, image/jpeg)
2011-04-05 21:15 UTC, Vitaly Minko 		Details
Add an attachment (proposed patch, testcase, etc.)

Description Vitaly Minko 2011-03-31 23:37:21 UTC 
Created attachment 52842 [details]
photo demonstrating the issue

LCD displays garbage (blue blobs) in dark areas of images.
See the attached original image and the photo demonstrating the issue.

Notes:
1. Not reproducible when KMS is disabled
2. Not related to X-system, I can reproduce this issue via framebuffer
3. Not 2.6.36-specific, I can reproduce this issue with all previous versions with KMS enabled

Machine: Lenovo ThinkPad X200
Video processors: Intel GMA 4500MHD
LCD panel: AUO B121EW03 V.6
Comment 1 Vitaly Minko 2011-03-31 23:38:06 UTC 
Created attachment 52852 [details]
original image
Comment 2 Vitaly Minko 2011-03-31 23:39:16 UTC 
Created attachment 52862 [details]
kernel config
Comment 3 Vitaly Minko 2011-03-31 23:39:45 UTC 
Created attachment 52872 [details]
lspci -v
Comment 4 Vitaly Minko 2011-03-31 23:40:57 UTC 
Created attachment 52882 [details]
GRUB config
Comment 5 Chris Wilson 2011-04-05 13:02:04 UTC 
In what way is this not reproducible !KMS. The error looks like a gamma issue (bad coloration near zero).
Comment 6 Vitaly Minko 2011-04-05 21:13:50 UTC 
I noticed this issue when I tried KMS first time (I guess it was 2.6.32, but I'm not sure). I switched to KMS using the same kernel version and the same userspace. Now it's quite hard to try X.org with KMS disabled, because the intel driver no longer supports no-KMS kernels.

However, here is another example - viewing the same image via vesafb: no blue blobs.
Comment 7 Vitaly Minko 2011-04-05 21:15:28 UTC 
Created attachment 53602 [details]
the same image displayed via vesafb
Comment 8 Vitaly Minko 2011-04-06 04:24:06 UTC 
BTW, this issue is not reproducible on external LCD connected via DisplayPort.
Comment 9 Vitaly Minko 2011-04-14 22:28:11 UTC 
You are right about gamma. `xgamma -gamma 0.8` makes the blue blobs disappear.
Comment 10 Jesse Barnes 2012-04-18 21:44:56 UTC 
Does this still happen in current kernels?  Or did you fix it by changing your default gamma?
Comment 11 Vitaly Minko 2012-04-19 08:20:47 UTC 
I can not test this with current kernels since I replaced the LCD.
Previous LCD: AUO B121EW03 V.6
Current LCD: Samsung LTN121AP02-001.
This issue is not reproducible with the new LCD.
Comment 12 Daniel Vetter 2012-04-19 08:25:11 UTC 
Closing as unreproducible - the test setup doesn't exist any more.
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