Bug 31519 - [915 TV(integrated)] querying Randr-information enables LVDS output due to spurious transient TV detection
Summary: [915 TV(integrated)] querying Randr-information enables LVDS output due to sp...
Status: CLOSED FIXED
Alias: None
Product: DRI
Classification: Unclassified
Component: DRM/Intel (show other bugs)
Version: unspecified
Hardware: x86 (IA32) Linux (All)
: medium normal
Assignee: Paulo Zanoni
QA Contact: Intel GFX Bugs mailing list
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2010-11-09 23:56 UTC by Uwe Kleine-König
Modified: 2016-10-07 10:58 UTC (History)
5 users (show)

See Also:
i915 platform:
i915 features:

Attachments
dmesg (29.60 KB, text/plain)
2010-11-10 00:24 UTC, Uwe Kleine-König 		no flags Details
dmesg with drm.debug=0xe (186.10 KB, text/plain)
2011-02-03 01:57 UTC, Uwe Kleine-König 		no flags Details
fixup TV load detect (4.75 KB, patch)
2012-11-13 13:21 UTC, Daniel Vetter 		no flags Details | Splinter Review
View All

Description Uwe Kleine-König 2010-11-09 23:56:32 UTC 
Chipset: 915GM
System arch: i686
Distribution: Debian
Machine: Thinkpad X41
related packages:
  libdrm-intel1: 2.4.22-2
  xserver-xorg: 1:7.5+7
  xserver-xorg-core: 2:1.7.7-8
  xserver-xorg-video-intel: 2:2.13.0-2
  linux-image-2.6.36-trunk-686: 2.6.36-1~experimental.1

When I run

    xrandr --output LVDS1 --off

the LVDS output goes off (as expected), but then running

    xrandr

reenables it again (and thus behaves like

    xrandr --auto

).  This didn't happen on Debian's linux-image-2.6.32-5-686 (2.6.32-27) kernel.
Comment 1 Uwe Kleine-König 2010-11-10 00:24:31 UTC 
Created attachment 40174 [details]
dmesg

As requested by ickle in #intel-gfx the resulting kernel messages after:

  # echo 0xe > /sys/module/drm/parameters/debug
  $ xrandr --output LVDS1 --off
  $ xrandr
  # echo 0 > /sys/module/drm/parameters/debug
Comment 2 Chris Wilson 2010-11-10 06:18:21 UTC 
Spurious SDVO TV detection. It comes, it goes, the display is reconfigured.
Comment 3 Chris Wilson 2011-02-01 04:42:26 UTC 
This [applied to -fixes] should fix the transient SDVO detections:

commit d121a5d2a098ba6dd033dd195f5ccbf7558c37b6
Author: Chris Wilson <chris@chris-wilson.co.uk>
Date:   Tue Jan 25 15:00:01 2011 +0000

    drm/i915/sdvo: If at first we don't succeed in reading the response, wait
    
    We were not pausing after detecting the response was pending and so did
    not allow the hardware sufficient time to complete before aborting. This
    lead to transient failures whilst probing SDVO devices.
    
    Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=30235
    Reported-by: Knut Petersen <Knut_Petersen@t-online.de>
    Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Comment 4 Uwe Kleine-König 2011-02-01 11:45:32 UTC 
Just tested current -fixes and this isn't resolved for me.
Comment 5 Chris Wilson 2011-02-01 11:58:52 UTC 
Can you attach the debug dmesg from early in the boot? I confused the integrated TV with an SDVO TV device on another bug, and I may have done the same here as well...
Comment 6 Uwe Kleine-König 2011-02-03 01:57:41 UTC 
Created attachment 42888 [details]
dmesg with drm.debug=0xe

for your rainy afternoons :-)
Comment 7 Chris Wilson 2011-07-10 06:08:20 UTC 
One workaround would be to pass video=SVIDEO-1:d on the boot commandline. (Just fyi.)
Comment 8 Daniel Vetter 2012-11-13 13:21:43 UTC 
Created attachment 70005 [details] [review]
fixup TV load detect

While strolling through docs I've noticed that we don't implement TV load detection according to what docs would have us do.

This patch attempts to fix that, but due to lack of hw totally untested. Testing feedback highly welcome.
Comment 9 Jani Nikula 2012-12-10 14:07:52 UTC 
(In reply to comment #8)
> This patch attempts to fix that, but due to lack of hw totally untested.
> Testing feedback highly welcome.

-> NEEDINFO
Comment 10 Jesse Barnes 2012-12-11 19:46:54 UTC 
It must be fixed, right Uwe? :)
Comment 11 Jari Tahvanainen 2016-10-07 10:58:55 UTC 
Closing resolved+fixed since no update in ~4 years.

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