See https://patchwork.kernel.org/project/linux-…@collabora.com/ for the main patches that added CEC support upstream, but there are follow-up fixes and everything becomes entwined in other DRM bridge work so backporting patches to an older kernel would be a painful task.
Thankfully current kernels have everything merged, so LE13 nightlies (6.18) and images in my test share (6.19) should have working HDMI-CEC support.
I installed LibreELEC on the ThinkCentre, then copied the Kodi configuration from the Pi.
For the sake of experimenting: stop Kodi, move /storage/.kodi to /storage/.kodi-old and restart Kodi. This gives you a clean Kodi install (reverting is just the reverse procedure). Configure the HDMI output and reboot a few times. Does the issue still occur?
Things work better on LE due to the OS being overall lighter and because Kodi setup with adjust-refresh and whitelists etc. requires less compute resources during playback than a desktop app under wayland that's forced to resample audio and video to run at the desktop rate of 1080@60Hz or 4K@60Hz.
The buffer size issue is the main thing to focus on for VDPU346. The VP9 patches seem to work well and I'm coaching Abhi Sarma on kernel etiquette so hopefully a v1 series can be sent for review soon.
The minor tearing/glitches that can be seen when the Kodi OSD is active are the result of refactoring in the ffmpeg patches (dealing with ffmpeg developer feedback/requirements) and additional work in Kodi is needed to get back to the previous state where there were no artefacts. More patch series need to be merged down, then some effort can go into investigating that.
Did you backup the RPi4 and restore to the ThinkCentre? or make a clean install on the ThinkCentre?
I've read the feedback. I'm still experimenting with AI tools to see if they can bridge the gap in my rather lightweight coding skills or we have to resort to nagging Collabora folks to take over (or cap the current driver at 1080p to get an initial merge).
HDR works, 8-bit only? (HDR is better when 10-bit but it's not mandatory) as RK3566/68 use the older Rockchip HDMI IP which has more colour support upstream. The newer one used with RK3588 etc. is still missing some infoframe handling IIRC.
btw, Jonas believes https://github.com/torvalds/linux…2fdfc001d044bee might have resolved the "wiotlb buffer is full" IOMMU issue that requires RAM to be capped under 4GB. I'm going to remove the cap on my boards and see if I still get a load of weird errors. Please do the same on your LE images.
docker run --rm --log-driver none -v `pwd`:/build -w /build -it libreelec make image^ from documentation, no script required. User claims Docker proficiency so you have to draw the line somewhere 
Read: https://kodi.wiki/view/Internet_video_and_audio_streams
Create .strm files for each Soundcloud URL that you want to use as media. Kodi treats these like a media file with no metadata.
Create .nfo files for each .strm file. This is required. It also provides a way to add metadata, e.g. pretty names, if wanted.
Scrape the .nfo files to the Library.
Add Library items to a playlist.
Do something with the playlist, like script it being started 20 seconds after Kodi starts (how you do that is .. Google'able).
Plan B .. get a Raspberry Pi and use one of the many good niche distros or RPiOS installable apps/containers designed for "signage" use-cases, as that appears to be the end goal and something Kodi is not really designed for.
axel I've spoken to Radxa about the AIC8800 wireless chip a couple of months ago as it's also fitted to one the boards I've been using to test. Radxa have no plans to upstream the driver as this would require a large effort, i.e. complete rewrite as the current quality of driver code would never be accepted into the kernel, and after years of working to rid our codebase of the maintenance burden of downstream (mostly Realtek) drivers we have no desire to add technical dept in the form of another vendor driver that has no plan to be upstreamed. I've shared our surprise/annoyance and position, and have strongly suggested they stick to using Broadcom, Qualcomm, Realtek (now upstream) chips in future iterations of current boards and future board designs so distros can avoid the need for crap drivers. I'm not sure LibreELEC's opinion will carry much commercial weight with them, but from our side, there's no action to be taken.
If you are proficient in Docker then it should be trivial for you to use the Docker files in tools/Docker that result in a pre-configured and working build environment for creating an LE image. Once you have a working LE image, add a package for the xone driver and build it into the image and push the changes to GitHub/Gitlab etc. so others can see the package.mk recipe.
It is not impossible to build a driver add-on, but the general challenge is that kernel modules must have the same 'version magic' as the running kernel, and in LE the add-on repo version is loosely aligned to Kodi API version and not kernel version. This means for each add-on repo version users will have a range of different kernel versions in use. The kernel's media-tree used to support 'media build' which provides a method for compiling and running 'DVB' kernel modules from an older codebase to run on a newer kernel version. LE has previously used this to package a bunch of DVB drivers for e.g. TBS cards as an add-on. We have since stopped doing this because it's a pain in the rear to maintain, but the prior art still exists in the buildsystem and you could use the same approach to create an add-on for the Xone driver.
Zero 3W, and it booted fine however, no wifi card appears to be detected, nor bluetooth
I can see that device-tree defines the module, but I can't see anything in documentation that states which Broadcom chipset is being used. It's probably something new(er) that we don't have firmware for, but as you didn't share the system log .. that's only a blind guess and could be wrong. In short .. no idea
axel I forget exactly what the issue is, but IOMMU errors are seen with RAM sizes over 4GB so LE currently and intentionally sets mem=3838M in kernel boot params to sidestep the problem. You are free to remove that param and see the full 8GB, but expect other issues. NB: LE runs in under 1GB so it has zero functional impact on Kodi use.
You can refer to https://kodi.wiki/view/Official:Forum_rules/Banned_add-ons
Most of the staff and forum regulars around here (self included) don't bother looking any further into a log the moment they see them installed.
Will there be an update from 21.2 to 21.3?
If Kodi release a 21.3 version we will push another LE update to include it.
NB: Kodi have no current plan for one. The focus really needs to be on getting K22 shipped.
SSH in to the box, make /flash writeable with mount -o remount,rw /flash then append video=HDMI-A-1:1360x720M@60D to kernel boot params in syslinux.cfg in the boot partition and it will force the initial kernel DRM state for the HDMI-A-1 connector to use that mode. For this to work the kernel needs to detect/see that mode via EDID data on the same connector. Adjust the connector name to match whatever HDMI port is being used (if there is more than one). Adjust the resolution to one that is listed if not, e.g. if the TV supports 1080p then use 1920x1080 not 1360x720. The kernel is probably auto-selecting an initial display mode based on the modes advertised but for some reason the TV doesn't actually like that mode (bad EDID data can be a thing sometimes). The same is seen sometimes with 4K TV's and forcing the initial state to 1080p helps.
Always post the solution!
Thanks for testing and confirming it's the same issue. I'll revist the bug report with Intel devs to inform that their latest fancy card suffers the same fate as a cheap N100 box. I can't guarantee it will stimulate action, but nothing to lose.
EDIT: comment added to https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/10199
Bring up the OSD .. click on the (i) button and remove (i)nfo from the screen. Or press 'i' from a connected USB keyboard. Or press 'i' when using the kodi-remote virtual remote over SSH.
I'll try to go through the link you sent me in detail soon. If I have some questions, would it be OK to ask you back here in this thread?
Sure. In high-level detail: Create a default image first, then all you need to do is modify the kernel defconfig enabling the missing kernel options then re-run the same build command. The buildsystem will run through the image build process again but only rebuild the kernel package. Once complete, push the image .tar or .img.gz file to /storage/.update and reboot to update using the custom image.
