Open MichaelBrunn3r opened 3 months ago
Yes, this looks like a MST issue. With more information I may be able to say a bit more. Please run ddcutil interrogate and submit the output as an attachment of some sort. If it's convenient, please build from branch 2.1.5-dev, as it has improved diagnostics in this area.
Thx for taking the time. I'm unable to build 2.1.5-dev, because the instructions from the website fail:
> ./autogen.sh
autoreconf: export WARNINGS=
autoreconf: Entering directory '.'
autoreconf: configure.ac: not using Gettext
autoreconf: running: aclocal -I config -I m4 --force -I m4 ${ACLOCAL_FLAGS}
autoreconf: configure.ac: tracing
autoreconf: running: libtoolize --copy --force
libtoolize: putting auxiliary files in AC_CONFIG_AUX_DIR, 'config'.
libtoolize: copying file 'config/ltmain.sh'
libtoolize: putting macros in AC_CONFIG_MACRO_DIRS, 'm4'.
libtoolize: copying file 'm4/libtool.m4'
libtoolize: copying file 'm4/ltoptions.m4'
libtoolize: copying file 'm4/ltsugar.m4'
libtoolize: copying file 'm4/ltversion.m4'
libtoolize: copying file 'm4/lt~obsolete.m4'
autoreconf: configure.ac: not using Intltool
autoreconf: configure.ac: not using Gtkdoc
autoreconf: running: aclocal -I config -I m4 --force -I m4 ${ACLOCAL_FLAGS}
autoreconf: running: /nix/store/2jk7wsszi0p265vxbxmpvwnk5z04k7ii-autoconf-2.72/bin/autoconf --include=config --include=m4 --force
configure.ac:52: error: possibly undefined macro: AC_MSG_NOTICE
If this token and others are legitimate, please use m4_pattern_allow.
See the Autoconf documentation.
configure.ac:226: error: possibly undefined macro: AC_MSG_ERROR
configure.ac:640: error: possibly undefined macro: AC_MSG_WARN
autoreconf: error: /nix/store/2jk7wsszi0p265vxbxmpvwnk5z04k7ii-autoconf-2.72/bin/autoconf failed with exit status: 1
configure: error: cannot find required auxiliary files: config.guess config.sub compile ar-lib missing install-sh
Maybe I'm missing some dependencies?
But here is the output for 2.1.4: ddcutil-interrogate.txt
First, regarding the build problem, it appears that there's something unexpected about autotools configuration on nixos. I presume that the 2.1.4 package you installed was somehow built on nixos, so I would look at how that build was done.
That said, the 2.1.4 interrogate output is sufficient for our purposes.
Yes, it's a driver issue. You're running a current kernel, which would have a recent i915 driver, so the problem probably lies in your particular hardware. I suspect there's something about the UGREEN hub that's unexpected. You can try posting to the i915 driver list. They may have some diagnostics you can run, bit I'd not be too hopeful.
Thx for the pointers, I will try out posting on the i915 driver list.
In the meantime I borrowed a USB-C to HDMI adapter (also from UGREEN) and connected it to another thunderbolt port, but with that one DDC doesn't work at all. Maybe a UGREEN issue. I will look into finding a proven working adapter. Adding a 2nd cable isn't that bad of a backup solution.
Do you think the Linux Kernel DDCCI driver (https://gitlab.com/ddcci-driver-linux/ddcci-driver-linux) will work any better? It was mentioned on some posts about DDC, but I can't test it rn, because its broken in NixOS :D
I don't see how ddcci would make any difference. Essentially it adds a layer on top of what driver i2c-dev (which ddcutil uses) does, The layer understands some DDC/CI features such as brightness, and presents the information through sysfs. Multi-stream transport is handled deep down in the video driver layers of the call stack.
Hi, I'm connecting 2 external monitors via a Thunderbolt dock (UGREEN Revodok Pro 308) to my laptop and want to control their brightness. When I connect only 1 monitor via HDMI to the dock, I can control it's brightness via ddcutil:
(I excluded the entry for the laptop display)
But I cannot control either of the monitors if I connect the second one:
(somehow it only shows the laptop entry and 1 monitor entry, not 2)
I tried to test all possible combinations, connecting each monitor individually, over HDMI and DP, but it always stops working if 2 monitors are connected.
From reading issues on this repo and a discussion you started on freedesktop, I think this should be DP MST issue? As far as I understand this is a driver issue and not something ddcutil can fix, but since this is a little over my head I wanted to ask for directions of where I can report this issue.
Additional information
ddcutil 2.1.4
OS:NixOS 24.05
Graphics:Intel Graphics (ADL GT2)
(i5-1240P) DE:GNOME 46
on Wayland Kernel:6.10.5