I am affected by this bug too on a Dell Latitude 14" 2-in-1.
~$ apt list --installed | grep linux-image
WARNING: apt does not have a stable CLI interface. Use with caution in
scripts.
linux-image-5.4.0-rc8/now 5.4.0-rc8-2 amd64 [installato, locale]
linux-image-5.5.0-0.bpo.2-amd64/buster-backports,now 5.5.17-1~bpo10+1
amd64 [installato, automatico]
linux-image-5.5.0-rc5-amd64/now 5.5~rc5-1~exp1 amd64 [installato, locale]
linux-image-amd64/buster-backports,now 5.5.17-1~bpo10+1 amd64 [installato]
Sound was working on a custom built 5.4.0-rc8 and on the 5.5.0-rc5 from
experimental, but after the upgrade to 5.5.0-0.bpo.2 I have only a
"Dummy output" in my mixer.
The results of journalctl -b | grep "00:1f\.3" are
== 5.5.0-rc5 == working sound ==
~# journalctl -b | grep "00:1f\.3"
mag 17 17:04:19 dentdherens kernel: pci 0000:00:1f.3: [8086:02c8] type
00 class 0x040100
mag 17 17:04:19 dentdherens kernel: pci 0000:00:1f.3: reg 0x10: [mem
0x6001118000-0x600111bfff 64bit]
mag 17 17:04:19 dentdherens kernel: pci 0000:00:1f.3: reg 0x20: [mem
0x6001000000-0x60010fffff 64bit]
mag 17 17:04:19 dentdherens kernel: pci 0000:00:1f.3: PME# supported
from D3hot D3cold
mag 17 17:04:19 dentdherens kernel: pci 0000:00:1f.3: Adding to iommu
group 12
mag 17 17:04:19 dentdherens kernel: snd_hda_intel 0000:00:1f.3: DSP
detected with PCI class/subclass/prog-if info 0x040100
mag 17 17:04:19 dentdherens kernel: snd_hda_intel 0000:00:1f.3: enabling
device (0000 -> 0002)
mag 17 17:04:19 dentdherens kernel: snd_hda_intel 0000:00:1f.3: bound
0000:00:02.0 (ops i915_audio_component_bind_ops [i915])
mag 17 17:58:20 dentdherens kernel: input: HDA Digital PCBeep as
/devices/pci0000:00/0000:00:1f.3/sound/card0/input30
mag 17 17:58:20 dentdherens kernel: input: HDA Intel PCH Headphone Mic
as /devices/pci0000:00/0000:00:1f.3/sound/card0/input31
mag 17 17:58:20 dentdherens kernel: input: HDA Intel PCH HDMI/DP,pcm=3
as /devices/pci0000:00/0000:00:1f.3/sound/card0/input32
mag 17 17:58:20 dentdherens kernel: input: HDA Intel PCH HDMI/DP,pcm=7
as /devices/pci0000:00/0000:00:1f.3/sound/card0/input33
mag 17 17:58:20 dentdherens kernel: input: HDA Intel PCH HDMI/DP,pcm=8
as /devices/pci0000:00/0000:00:1f.3/sound/card0/input34
mag 17 17:58:20 dentdherens kernel: input: HDA Intel PCH HDMI/DP,pcm=9
as /devices/pci0000:00/0000:00:1f.3/sound/card0/input35
mag 17 17:58:20 dentdherens kernel: input: HDA Intel PCH HDMI/DP,pcm=10
as /devices/pci0000:00/0000:00:1f.3/sound/card0/input36
=======================
== 5.5.0-0.bpo.2 == sound not working ==
mag 17 17:14:29 dentdherens kernel: pci 0000:00:1f.3: [8086:02c8] type
00 class 0x040100
mag 17 17:14:29 dentdherens kernel: pci 0000:00:1f.3: reg 0x10: [mem
0x6001118000-0x600111bfff 64bit]
mag 17 17:14:29 dentdherens kernel: pci 0000:00:1f.3: reg 0x20: [mem
0x6001000000-0x60010fffff 64bit]
mag 17 17:14:29 dentdherens kernel: pci 0000:00:1f.3: PME# supported
from D3hot D3cold
mag 17 17:14:29 dentdherens kernel: pci 0000:00:1f.3: Adding to iommu
group 12
mag 17 17:14:29 dentdherens kernel: snd_hda_intel 0000:00:1f.3: DSP
detected with PCI class/subclass/prog-if info 0x040100
mag 17 17:14:29 dentdherens kernel: snd_hda_intel 0000:00:1f.3: Digital
mics found on Skylake+ platform, using SOF driver
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: DSP
detected with PCI class/subclass/prog-if info 0x040100
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: Digital
mics found on Skylake+ platform, using SOF driver
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: enabling
device (0000 -> 0002)
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: warning:
No matching ASoC machine driver found
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: DSP
detected with PCI class/subclass/prog-if 0x040100
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: use msi
interrupt mode
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: bound
0000:00:02.0 (ops i915_audio_component_bind_ops [i915])
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: hda
codecs found, mask 5
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: using
HDA machine driver skl_hda_dsp_generic now
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3:
firmware: failed to load intel/sof/sof-cml.ri (-2)
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: Direct
firmware load for intel/sof/sof-cml.ri failed with error -2
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: error:
request firmware intel/sof/sof-cml.ri failed err: -2
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: error:
failed to load DSP firmware -2
mag 17 18:08:38 dentdherens kernel: sof-audio-pci 0000:00:1f.3: error:
sof_probe_work failed err: -2
===========================
It seems that the version in backports recognizes the "Digital mics
found on Skylake+ platform, using SOF driver" but then fails to load a
firmware for it, whereas the 5.5.0-rc5 version did not recognize the
"digital mic" but at least gave a working speaker and mic/headphone jack.
Matteo S.
