Arch Linux

paolopani

Member

Registered: 2015-04-09

Posts: 8

No displayport detected (Lenovo x220, i915 drivers)

Hi,

I have a Lenovo Thinkpad X220 and want to connect it to an external monitor through the displayport (DP). After plugging the cable, the monitor remains black and KDE Settings nor xrandr show any detected output other than the laptop screen. I spent one day browsing through forums but I'm not sure whether this is a known issue or not. It seems that those who can switch to nvidia drivers have sometimes solved the issue, but I don't have a nvidia card.

The external monitor on DP works during the boot, but stops working after kdm is loaded.

Thanks for the support.

ugjka

Member

From: Latvia

Registered: 2014-04-01

Posts: 1,952

Website

Re: No displayport detected (Lenovo x220, i915 drivers)

Are you using Arch or Chakra? http://chakraos.org/forum/viewtopic.php?id=13869

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https://ugjka.net

paolopani

Member

Registered: 2015-04-09

Posts: 8

Re: No displayport detected (Lenovo x220, i915 drivers)

Are you using Arch or Chakra? http://chakraos.org/forum/viewtopic.php?id=13869

I have this problem with all distributions I've tried so far (Charka, arch, fedora and ubuntu).

paolopani

Member

Registered: 2015-04-09

Posts: 8

Re: No displayport detected (Lenovo x220, i915 drivers)

UPDATE: Today i've also tried to use a DP-to-HDMI cable and connected the laptop to the HDMI port of the TV (today I cannot use the same screen I was referring to the other day) because I've read that using a DP-HDMI adapter fixed similar issues for some other user. However, even in this case the TV is not recognized in xrandr.

I think i'll install Windows over the weekend, just to make sure the DP works correctly. However, I think this is the case because the DP does work during the boot (my BIOS has an option to output the boot over DP instead of using the laptop screen) but stops working after the DE is loaded. For some reason, it seems that Linux does not recognize the DP at all!

teateawhy

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From: GER

Registered: 2012-03-05

Posts: 1,138

Website

Re: No displayport detected (Lenovo x220, i915 drivers)

You are right that DP does not work in linux with x220. I have an x220 and i am using VGA for this reason.

Last edited by teateawhy (2015-04-10 21:49:45)

paolopani

Member

Registered: 2015-04-09

Posts: 8

Re: No displayport detected (Lenovo x220, i915 drivers)

You are right that DP does not work in linux with x220. I have an x220 and i am using VGA for this reason.

I find this very weird. Judging from here: https://help.ubuntu.com/community/X220 and here: http://www.thinkwiki.org/wiki/DisplayPort it seems it should work...

paolopani

Member

Registered: 2015-04-09

Posts: 8

Re: No displayport detected (Lenovo x220, i915 drivers)

You are right that DP does not work in linux with x220. I have an x220 and i am using VGA for this reason.

I find this very weird. Judging from here: https://help.ubuntu.com/community/X220 and here: http://www.thinkwiki.org/wiki/DisplayPort it seems it should work...

Please, see also this: http://osdir.com/ml/ubuntu-bugs/2013-10/msg12600.html it seems that (at least) it used to work in some cases...

teateawhy

Member

From: GER

Registered: 2012-03-05

Posts: 1,138

Website

Re: No displayport detected (Lenovo x220, i915 drivers)

You made me try this out again, and now it works. The last time i tried this was last year. Seems like a kernel or i915 update has fixed it. Or maybe it was the procedure i did when connecting DP...
Laptop was suspended. Plugged in DP, resumed from suspend, xrandr listed DP, did xrandr --auto and it worked.
EDIT:
Packages up-to-date, linux 3.19.3-3, xf86-video-intel 2.99.917-4, only integrated GPU no nvidia

Last edited by teateawhy (2015-04-10 22:42:33)

paolopani

Member

Registered: 2015-04-09

Posts: 8

Re: No displayport detected (Lenovo x220, i915 drivers)

You made me try this out again, and now it works. The last time i tried this was last year. Seems like a kernel or i915 update has fixed it. Or maybe it was the procedure i did when connecting DP...
Laptop was suspended. Plugged in DP, resumed from suspend, xrandr listed DP, did xrandr --auto and it worked.

Good to hear that, there's still hope then!
Could you please tell me your kernel version and the version of your i915 package (I assume you use xf86-video-intel, right?).

paolopani

Member

Registered: 2015-04-09

Posts: 8

Re: No displayport detected (Lenovo x220, i915 drivers)

You made me try this out again, and now it works. The last time i tried this was last year. Seems like a kernel or i915 update has fixed it. Or maybe it was the procedure i did when connecting DP...
Laptop was suspended. Plugged in DP, resumed from suspend, xrandr listed DP, did xrandr --auto and it worked.
EDIT:
Packages up-to-date, linux 3.19.3-3, xf86-video-intel 2.99.917-4, only integrated GPU no nvidia

[It took me a while to realize you have actually replied to my question by editing your previous post ] Anyway, no luck, i've updated the kernel and the intel driver but it still doesn't work. Can you please confirm you use a DP to DP cable?

teateawhy

Member

From: GER

Registered: 2012-03-05

Posts: 1,138

Website

Re: No displayport detected (Lenovo x220, i915 drivers)

Yes, DP to DP cable.

What i would try if i were you is a minimal windowmanager like openbox or i3 instead of a desktop environment like KDE, and not use a login manager. The DE's and login managers mess with the display configuration, while the WM's leave display configuration to the user. Try to install openbox or i3, disable the login manager, and use startx and xinitrc to start the window manager. Then run xrandr and maybe also
xrandr --output DP1 --auto --output LVDS1 --off
and see what happens.
This is basically what i do. I have the command xrandr --DP1 --auto --output LVDS1 --off in xinitrc, and i use i3 with startx and no login manager. Also i have the monitor connected and powered on when i start the laptop. Try to replicate that setup.

Also this bug report lists some workarounds.
https://bugs.launchpad.net/ubuntu/+sour … ug/1263681

What is your BIOS version? Maybe you have to update it, though my BIOS version is rather old now at 1.33.

EDIT: Also check: maximum external resolution 2560x1600 (DisplayPort) @60Hz
         and: A simpler workaround: pressing Fn-Home/Fn-End (screen brightness control keys) after plugging in the DisplayPort cable also triggers detection.
         Also try those kernel commandline options that i'm using: vga=current video.use_native_backlight=0
Also: The monitor already works in early boot during initramfs stage.

Last edited by teateawhy (2015-04-14 14:05:42)

paolopani

Member

Registered: 2015-04-09

Posts: 8

Re: No displayport detected (Lenovo x220, i915 drivers)

Thanks teateawhy for the support! Latest news is I've updated the BIOS to 1.38 (was still on 1.28) but it didn't help...I'll go through your other suggestions now and keep the forum posted...