Bug 26865 - [R600] LCD panel black (backlight on) with VGA screen plugged
Summary: [R600] LCD panel black (backlight on) with VGA screen plugged
Status: RESOLVED FIXED
Alias: None
Product: xorg
Classification: Unclassified
Component: Driver/Radeon (show other bugs)
Version: 7.5 (2009.10)
Hardware: Other All
: medium normal
Assignee: xf86-video-ati maintainers
QA Contact: Xorg Project Team
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2010-03-03 08:08 UTC by BBT
Modified: 2010-04-03 08:26 UTC (History)
1 user (show)

See Also:
i915 platform:
i915 features:

Attachments
Xorg.conf (3.34 KB, text/plain)
2010-03-03 08:08 UTC, BBT 		no flags Details
Xorg log (79.08 KB, text/plain)
2010-03-03 08:10 UTC, BBT 		no flags Details
gdb trace with VGA screen unplugged (10.89 KB, text/plain)
2010-03-03 08:18 UTC, BBT 		no flags Details
gdb trace for VGA unplugged (10.50 KB, text/plain)
2010-03-03 08:23 UTC, BBT 		no flags Details
gdb trace for VGA plugged after initialization (10.89 KB, text/plain)
2010-03-03 08:24 UTC, BBT 		no flags Details
Show Obsolete (1) View All

Description BBT 2010-03-03 08:08:50 UTC 
Created attachment 33727 [details]
Xorg.conf

OS: Debian/testing
linux-image-2.6.32-trunk-686 = 2.6.32-5
firmware-linux-nonfree = 0.22
xserver-xorg-video-radeon = 1:6.12.4-2
xserver-xorg = 1:7.5+3
xserver-xorg-core = 2:1.7.5-1
x11-xserver-utils = 7.5+1+b1

Chipset: ATI Radeon Xpress 1250 (RS600M or RS690M ?)
Laptop: Samsung R20


I can't have dual head setup (LVDS/VGA-0),
LCD panel becomes black (with backlight on, xrandr thinks it is on and normal)
at any xrandr operation I tried.


== Test Cases ==

1- boot without VGA plugged

xrandr works properly, no black screen.

2- boot with VGA plugged

VGA works correctly, LCD panel is black.
xrandr works.

3- boot without VGA plugged, VGA is plugged after initialization is complete

LCD panel works, VGA is not used.
Typing "xrandr" make the LCD panel become black,
nothing happens on VGA.


for case 3, I investigated a little on xrandr,
the blanking happens on XRRGetScreenRessources(dpy, root) in xrandr.c:1086.
gdb traces following for xrandr context when XRRGetScreenRessources is called.
Comment 1 BBT 2010-03-03 08:10:07 UTC 
Created attachment 33728 [details]
Xorg log
Comment 2 Alex Deucher 2010-03-03 08:16:04 UTC 
Does xf86-video-ati from git master or 6.12.5 work any better?
Comment 3 BBT 2010-03-03 08:18:35 UTC 
Created attachment 33729 [details]
gdb trace with VGA screen unplugged

This trace is included for reference,
this is case 1 where xrandr works properly.
Comment 4 BBT 2010-03-03 08:23:24 UTC 
Created attachment 33730 [details]
gdb trace for VGA unplugged

VGA unplugged during process (correcting mistake)
Comment 5 BBT 2010-03-03 08:24:12 UTC 
Created attachment 33731 [details]
gdb trace for VGA plugged after initialization
Comment 6 BBT 2010-03-03 08:36:58 UTC 
(In reply to comment #2)
> Does xf86-video-ati from git master or 6.12.5 work any better?
> 

I'm testing with libdrm-radeon1 (2.4.17-1) and xserver-xorg-video-radeon (1:6.12.99+git20100201.a887818f-1) from Debian/experimental.

Same behaviour here (but it seems faster ;) )
Comment 7 BBT 2010-04-03 08:26:38 UTC 
Fixed with upgrade of xserver-xorg-video-radeon from 1:6.12.99+git... to 1:6.12.192-2 and disabling KMS in /etc/modprobe.d/radeon-kms.conf.

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