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newsboost

Member

Registered: 2016-07-24

Posts: 157

[SOLVED] Resume from suspend monitor problem - Displayport switch

Hi,

Sorry if I'm aksing in the wrong place, but I got this small DisplayPort-switcher: https://www.delock.de/produkte/G_18750/ … anguage=en (4K monitor switcher) so that I can quickly switch between using the multi-monitor setup on my home/private laptop and on my work/office laptop. The problem is: I wish to be able to suspend my laptop while connected to the monitors and then resume and continue back working. But as my home laptop now resume's (my work-pc is hibernating, this problem isn't there), I think it quickly thinks that the external monitors are missing and I get totally black screens and everything completely unresponsive, so I then login via ssh and do a "pkill -9 Xorg" to terminate the WM (I'm using Awesome WM).

During first lockdown of the Corona-crisis (about a year ago) I think I remember I solved this by turning off and then turning on the external monitor and after 1-2 seconds resume (or turn on) the laptop. I think this ensured that the monitor was "listening and answering to signals" unlike if I just turned on the laptop... But I don't think this works anymore - so now I have to exit the window manager before resuming from suspend, which is kinda defeats the purpose of suspending in the first place, because the idea was that I could quickly continue where I left off - but not if I have to exit the WM and start it all over again... So I'm just frustrated... Anyone knows a solution? Maybe if there could be a 2-3 second delay before attempting to communicate with the monitor, maybe that would help? I don't know, am just frustrated, hope someone knows anything or what I could try, to solve this - also if you have or anyone has a recommendation for a hardware monitor switch (must be capable of 4K or 8K resolution) that works for suspend, I'll appreciate knowing about it, thanks!

UPDATE:For the record: The delock displayport switch now works again as intended! Explanation: So, I did some further digging and discovered that both even without the displayport swtich, I could no longer resume from suspend - nor hibernate. So it wasn't the switch. I first came across this page: https://download.nvidia.com/XFree86/Lin … ement.html - I then wrote

    sudo systemctl enable nvidia-suspend.service
    sudo systemctl enable nvidia-hibernate.service
    sudo systemctl enable nvidia-resume.service

Updated everything and restarted. But the next problem was that for a while I couldn't even start the Xserver, because it crashed after a few seconds. So I investigated the /var/log/Xorg.0.log file and got "Fatal server error:" & "[    75.832] (EE) no screens found(EE)" and for 1-2 hours I couldn't understand it. Then I reinstalled nvidia and nvidia-lts. Finally I found out, the nvidia-driver was only installed for the default linux kernel and for "version 1" lts-kernel, i.e. it was installed for 5.15.11-arch2-1 and the command "pacman -Ql nvidia-lts" revealed that I got the nvidia-driver installed into /usr/lib/modules/5.10.88-1-lts/ - but not into /usr/lib/modules/5.10.88-2-lts/, which is I now have for some strange reason (maybe it's because I tried running "mkinitcpio -P" ?). In any case, grub apparaently thought it should use the latest LTS, but "pacman -Ql nvidia-lts" says that it'll only install to e.g. /usr/lib/modules/5.10.88-1-lts/extramodules/nvidia.ko.xz so when grub boots 5.10.88-2-lts, it doesn't have the nvidia-kernel-driver and this explain why Xorg crashes and didn't want to start... After rebooting into the non-LTS kernel, things are working - so seems I just had to update all - just adding this, in case anyone experiences something similar, sorry for the confusion I think I almost could've solved this myself if I didn't trust linux and nvidia-drivers (reminds me that Linux Thorvalds also said "fuck you nvidia", I'll consider buying a radeon-GPU instead of nvidia next time)...

Last edited by newsboost (2021-12-23 16:52:40)