`--hwdec=auto --gpu-context=wayland` keeps my dGPU awake.

mpv Information

mpv v0.39.0 Copyright © 2000-2024 mpv/MPlayer/mplayer2 projects
 built on Sep 23 2024 17:46:22
libplacebo version: v7.349.0
FFmpeg version: n7.0.2
FFmpeg library versions:
   libavcodec      61.3.100
   libavdevice     61.1.100
   libavfilter     10.1.100
   libavformat     61.1.100
   libavutil       59.8.100
   libswresample   5.1.100
   libswscale      8.1.100

Other Information

- Linux version: "Arch Linux"
- Kernel Version: Linux Korialo-Arch 6.11.5-274-tkg-eevdf #1 SMP PREEMPT_DYNAMIC TKG Wed, 30 Oct 2024 21:58:24 +0000 x86_64 GNU/Linux
- GPU Model: 00:02.0 VGA compatible controller [0300]: Intel Corporation CometLake-H GT2 [UHD Graphics] [8086:9bc4] (rev 05)
01:00.0 VGA compatible controller [0300]: NVIDIA Corporation GA104M [GeForce RTX 3080 Mobile / Max-Q 8GB/16GB] [10de:249c] (rev a1)
- Mesa/GPU Driver Version: OpenGL version string: 4.6 (Compatibility Profile) Mesa 24.2.6-arch1.1
- Window Manager and Version: Hyprland, built from branch  at commit 4520b30d498daca8079365bdb909a8dea38e8d55  (version: bump to 0.44.1).
- Source mpv: pacman
- Introduced in version: na

Reproduction Steps

Just run:

  ~                                                                                                                                                                            took  23s at  20:40:04
❯ mpv --no-config --vo=gpu-next --hwdec=auto --gpu-context=wayland filename.mkv

in my case vaapi was shown as the decoder.
But when I check the dGPU status through:

  ~                                                                                                                                                                            took  20s at  20:48:34
❯ watch cat /sys/bus/pci/devices/0000:01:00.0/power/runtime_suspended_time

the counter stops indicating that my dGPU is currently running.
Now if I directly switch to --hwdec=vaapi, and ran the above command the dGPU is suspended.

Expected Behavior

If --hwdec=auto and vaapi is the decoding method, you expect the iGPU to be utilized, and dGPU is free to suspend/sleep.

Actual Behavior

Actually I don't fully understand how --hwdec=auto works, so I don't know if this an expected behavior or not, but the dGPU should not be running if not used.

Log File

output.txt

Sample Files

No response

I carefully read all instruction and confirm that I did the following:

• I tested with the latest mpv version to validate that the issue is not already fixed.
• I provided all required information including system and mpv version.
• I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of --log-file=output.txt.
• I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
• I attached the full, untruncated log file.
• I attached the backtrace in the case of a crash.

Reproduce the command using --hwdec=auto, --hwdec=vaapi, --vo=gpu-next, and --gpu-context=wayland while watching /sys/bus/pci/devices/0000:01:00.0/power/runtime_suspended_time. Compare the behavior with output.txt and determine whether mpv's hardware-decoder or Wayland GPU selection keeps the dGPU active; done means the behavior is explained and the reported mismatch is corrected if it is a bug.