[NVC1] HDMI audio device only visible after rescan
Submitted by Jean-Louis Dupond
Assigned to Nouveau Project
Description
Hi
I have a Dell XPS 15 laptop with Optimus.
It has the following NVIDIA card:
01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 540M] (rev a1)
The HDMI output is working fine since some time now.
Only there is still an issue with the HDMI audio.
On Windows, and with lspci -H1 it shows the following devices:
01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 540M] (rev a1)
01:00.1 Audio device: NVIDIA Corporation GF108 High Definition Audio Controller (rev a1)
But by default, the audio device isn't visible after a clean boot. So the HDMI audio ain't working.
Now I've found some workaround to get it working.
- Start the system, and stop the display manager (lightdm/gdm)
- Load the nouveau module
- Remove the Nvidia card from the PCI bus (echo 1 > /sys/bus/pci/devices/0000:01:00.0/remove)
- Rescan the PCI bus (echo "1" > /sys/bus/pci/rescan)
And there it is, the Audio device is visible now:
01:00.0 VGA compatible controller: NVIDIA Corporation GF108M [GeForce GT 540M] (rev a1)
01:00.1 Audio device: NVIDIA Corporation GF108 High Definition Audio Controller (rev a1)
Also dmesg shows the following:
[ 152.360864] input: HDA NVidia HDMI/DP,pcm=9 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input18
[ 152.361210] input: HDA NVidia HDMI/DP,pcm=8 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input17
[ 152.361415] input: HDA NVidia HDMI/DP,pcm=7 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input16
[ 152.361592] input: HDA NVidia HDMI/DP,pcm=3 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input15
So the device is loaded correctly.
Now if we start lightdm/gdm/whatever again, and login (which also starts PulseAudio), the HDMI audio works correctly like it should :)
Some note:
If we do the rescan without nouveau module loaded, the workaround does not work. So we need to have nouveau loaded to make the Audio device visible.
On first boot I get the following error:
[ 121.872253] nouveau 0000:01:00.0: enabling device (0006 -> 0007)
[ 121.872554] [drm] hdmi device not found 1 0 1
This might be related?
After the rescan, it shows the following:
[ 151.557038] [drm] Initialized nouveau 1.1.1 20120801 for 0000:01:00.0 on minor 1
[ 151.557186] snd_hda_intel 0000:01:00.1: enabling device (0000 -> 0002)
[ 151.557253] hda_intel: Disabling MSI
[ 151.557274] hda-intel 0000:01:00.1: Handle VGA-switcheroo audio client
[ 151.557349] hda-intel 0000:01:00.1: Disabling 64bit DMA
[ 151.560778] hda-intel 0000:01:00.1: Enable delay in RIRB handling
[ 152.360864] input: HDA NVidia HDMI/DP,pcm=9 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input18
[ 152.361210] input: HDA NVidia HDMI/DP,pcm=8 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input17
[ 152.361415] input: HDA NVidia HDMI/DP,pcm=7 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input16
[ 152.361592] input: HDA NVidia HDMI/DP,pcm=3 as /devices/pci0000:00/0000:00:01.0/0000:01:00.1/sound/card1/input15
[ 156.801404] hda-intel 0000:01:00.1: Disabling via VGA-switcheroo
Hopefully this can help getting the issue fixed completely :)
Thanks!
Jean-Louis