#694946 xserver-xorg-video-intel: [GM45] ThinkPad T400 LVDS stays blank after resume

Package:
xserver-xorg-video-intel
Source:
xserver-xorg-video-intel
Description:
X.Org X server -- Intel i8xx, i9xx display driver
Submitter:
Michael Banck
Date:
2012-12-02 18:03:07 UTC
Severity:
important
#694946#5
Date:
2012-12-02 15:46:35 UTC
From:
To:
Dear Maintainers,

I read #577996 and #584100 but am filing a new bug here because it is
still not clear to me those are the same (and are rather old).

In about 10-30%[0] of resumes (from RAM, haven't tried hibernate yet at
all) with this integrated Intel GM45 chipset on a ThinkPad T400 on
wheezy[1], the internal TFT stays blank (though the backlight is lit)
and I have so far not been able to get it working again short of a
reboot.

Sidenode: the ThinkPad sometimes suspends a second time immediately
after coming back from resume, and this was the case for the latest time
I had this issue (came up fine first, suspended, TFT gone after resume)
but I think there is no corellation between the two happening.

I can *not* switch to the VTs, or rather those do not work either on the
TFT (likely due to KMS).  However, I can easily attach an external TFT
and keep working there and am able to switch to the VTs and back as well.

I have not found anything suspicious in the syslog or the X.log.

When I run "xrandr --output LVDS1 --off" the backlight goes off, and
"xrandr --output LVDS1 --auto" switches it on again, but the display
still stays blank.

This is the xrandr output (including the external TFT):

|Screen 0: minimum 320 x 200, current 1440 x 900, maximum 8192 x 8192
|LVDS1 connected 1440x900+0+0 (normal left inverted right x axis y axis)
|304mm x 190mm
|   1440x900       60.1*+   59.9     49.9
|   1360x768       59.8     60.0
|   1152x864       60.0
|   1024x768       60.0
|   800x600        60.3     56.2
|   640x480        59.9
|VGA1 connected 1440x900+0+0 (normal left inverted right x axis y axis)
|477mm x 268mm
|   1920x1080      60.0 +
|   1600x1200      60.0
|   1680x1050      60.0
|   1280x1024      60.0
|   1440x900       59.9*
|   1280x960       60.0
|   1280x800       59.8
|   1024x768       60.0
|   800x600        60.3     56.2
|   640x480        60.0
|HDMI1 disconnected (normal left inverted right x axis y axis)
|DP1 disconnected (normal left inverted right x axis y axis)
|HDMI2 disconnected (normal left inverted right x axis y axis)
|DP2 disconnected (normal left inverted right x axis y axis)
|DP3 disconnected (normal left inverted right x axis y axis)

The other times I had to reboot quite fast because I needed the notebook
for work, but this time I tried to debug it a bit, when I had a GPU
crash which I will file upstream seperately, though maybe it is
connected.


Cheers,

Michael

[0] This is the third or fourth time this has happened and it seems to be
getting more frequent (one time last weekend, one time during this week, one
time right now this weekend; before I think I had this problem at most once or
twice).

[1] reinstalled with wheezy about 6 weeks ago, I ran squeeze on it before and did not have this issue

#694946#10
Date:
2012-12-02 17:58:43 UTC
From:
To:
Hi,

That bug is https://bugs.freedesktop.org/show_bug.cgi?id=57809


Michael