[SOLVED - workaround] xrandr keeps duplicating between HDMI1 and VGA1

petelewis · 2017-11-01 18:16:41

Hi,

Going a bit crazy with this... I have a laptop with integrated intel graphics. I'm using the xf86-video-intel driver. I have two external monitors connected, HDMI1 and VGA1, in addition to the laptop LVDS1 display.

When I do

xrandr --output LVDS1 --mode 1366x768 --output HDMI1 --mode 1920x1080 --right-of LVDS1 --output VGA1 --mode 1920x1080 --right-of HDMI1

I get VGA1 and HDMI1 displaying the same output, as if I'd said

--output VGA1 --same-as HDMI1

Confirming...

% xrandr -q

Screen 0: minimum 8 x 8, current 5206 x 1080, maximum 32767 x 32767
LVDS1 connected primary 1366x768+0+0 (normal left inverted right x axis y axis) 280mm x 170mm
   1366x768      60.01*+  40.00
   1280x720      60.00
   1024x768      60.00
   1024x576      60.00
   960x540       60.00
   800x600       60.32    56.25
   864x486       60.00
   640x480       59.94
   720x405       60.00
   680x384       60.00
   640x360       60.00
DP1 disconnected (normal left inverted right x axis y axis)
DP2 disconnected (normal left inverted right x axis y axis)
HDMI1 connected 1920x1080+1366+0 (normal left inverted right x axis y axis) 520mm x 290mm
   1920x1080     60.00*+
   1680x1050     59.88
   1280x1024     75.02    60.02
   1440x900      74.98    59.90
   1280x960      60.00
   1152x864      75.00
   1024x768      75.03    70.07    60.00
   832x624       74.55
   800x600       72.19    75.00    60.32    56.25
   640x480       75.00    72.81    66.67    59.94
   720x400       70.08
HDMI2 disconnected (normal left inverted right x axis y axis)
VGA1 connected 1920x1080+1366+0 (normal left inverted right x axis y axis) 480mm x 270mm
   1920x1080     60.00*+
   1680x1050     59.95
   1600x900      75.00    60.00
   1280x1024     75.02    70.00    60.02
   1440x900      59.89
   1152x864      75.00
   1024x768      75.03    70.07    60.00
   832x624       74.55
   800x600       72.19    75.00    60.32    56.25
   640x480       75.00    72.81    59.94
   720x400       70.08
VIRTUAL1 disconnected (normal left inverted right x axis y axis)

So both external monitors have the same x offset. If I try with --pos values instead, I get the same behaviour.

The only thing I can spot in the logs that looks slightly suspicious is in the Xorg log:

[535034.448] (II) intel(0): resizing framebuffer to 5206x1080
[535034.476] (II) intel(0): switch to mode 1920x1080@60.0 on HDMI1, VGA1 using pipe 0, position (1366, 0), rotation normal, reflection none

which confirms they are both somehow being set "together" on the same "pipe" (not sure what that is).

Any ideas? Happy to provide more details, if necessary.

Last edited by petelewis (2017-11-03 09:12:16)

seth · 2017-11-01 20:13:25

xrandr --verbose

Tried?

xrandr --output LVDS1 --mode 1366x768
xrandr --output HDMI1 --mode 1920x1080 --right-of LVDS1
xrandr --output VGA1 --mode 1920x1080 --right-of HDMI1

Xyne · 2017-11-01 20:40:57

Try configuring the screens with arandr (gui for xrandr). If that works, check the command it used with unxrandr.

petelewis · 2017-11-03 09:11:47

Thanks for the suggestions.

@xyne yeah, I originally generated the line from arandr. When setting it directly from the arandr GUI, it seemed to sometimes work and sometimes not. But from the script it generates, it never did.

seth's suggestion of setting it one monitor at a time works though. These two lines seem ok:

xrandr --output LVDS1 --mode 1366x768 --pos 0x0 --rotate normal --output VGA1 --off --output HDMI2 --off --output DP1 --off --output DP2 --off --output HDMI1 --primary --mode 1920x1080 --right-of LVDS1 --rotate normal

xrandr --output VGA1 --mode 1920x1080 --right-of HDMI1

even without any pausing in between them.

So I guess this is solved, from the point of view of a workaround, but it would be interesting to know why xrandr can't set them together.

seth · 2017-11-03 12:08:28

It looks like a bug - what I could explain was if it VGA would align to LVDS - because "right of HDMI" is "right of nothing" at the time you call it.
(Even then one might argue to preview the geometry caused by the switch before)

Arch Linux

#1 2017-11-01 18:16:41

[SOLVED - workaround] xrandr keeps duplicating between HDMI1 and VGA1

#2 2017-11-01 20:13:25

Re: [SOLVED - workaround] xrandr keeps duplicating between HDMI1 and VGA1

#3 2017-11-01 20:40:57

Re: [SOLVED - workaround] xrandr keeps duplicating between HDMI1 and VGA1

#4 2017-11-03 09:11:47

Re: [SOLVED - workaround] xrandr keeps duplicating between HDMI1 and VGA1

#5 2017-11-03 12:08:28

Re: [SOLVED - workaround] xrandr keeps duplicating between HDMI1 and VGA1

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