Pulseaudio reported a dummy device, alsamixer said there were devices, but they had no controls. Ubuntu 21.10 on a laptop with a graphics card.
Anyway, what solved it was to add this to /etc/default/grub, to the GRUB_CMDLINE_LINUX_DEFAULT line:
snd_hda_intel.dmic_detect=0
And then:
sudo grub-mkconfig -o /boot/grub/grub.cfg