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--- bloglike:2021-12 [2021/12/30 06:42] – Go green stybla
+++ bloglike:2021-12 [2021/12/31 17:37] (current) – Add Story about LCD display that wouldn't sleep stybla
@@ Line 50: / Line 50: @@
  --- //[[stybla@turnovfree.net|Zdenek Styblik]] 2021/12/30 12:42//
+===== Story about LCD display that wouldn't sleep =====
+Connecting LCD display by USB-C Thunderbolt seemed like a good idea at first, however it soon turned into nightmare - sort of. First of all, connecting display by USB-C doesn't automatically mean it's Thunderbolt device despite the fact this is indeed port which supports TB. It isn't, as I found out, which explains why no TB devices show up and there are no devices to be managed and why tools like ''xrandr'' report connection as DisplayPort-1. Also, if you actually have some TB hardware, then it's advised to connect display through HDMI or DisplayPort instead of occupying TB port which can be used for something else. On the other hand, I have no other TB capable hardware and 4K@30Hz at HDMI doesn't appeal to me.
+Second of all, there were random events like laptop falling asleep for no apparent reason or every time external display fell asleep(dim screen after X), display at the laptop woke up. This event led to another event - external display immediately woke up as well, "internal" one switched off, rinse and repeat until infinity. No such issues were observed when I had (another) display connected by HDMI. Since USB-C is used for power delivery as well, I just couldn't unplug the display whenever I "needed to" and be done with it. Long story short, I'm happy to say that it seems like setting "DP Hot-Plug Detection" from "Low Power" to "Always Active" on the display itself did the trick. No changes in Linux were necessary.
+ --- //[[stybla@turnovfree.net|Zdenek Styblik]] 2021/12/31 22:41//