Support for 8086:ae20 Intel Smart Sound Technology on Fujitsu Lifebook

[Pierre-Louis Bossart]

> today I realized that the built-in microphone (next to the webcam) 
> of my Fujitsu Lifebook U-series is not detected. (I usully use a
> headset, but due to travelling was forced to use the internal).
> 
> I tried hard to get this device working, but neither with my
> self-compiled kernel (5.15.6) nor the Debian kernel distribution kernel
> 5.15 the microphone seems to be detected.
> 
> I booted into Windows and tried to find out what the device might be. My
> **guess** is what is mentioned as
> 	Intel Smart Sound Technology
> with
> 	Vendor ID	8086
> 	Device ID	ae20
> I git grepped the kernel sources for this, and snd-hda-intel contains
> quite some mentioning about Vendor ID 8086, but ae20 is not appearing.

I checked in our internal sources and while I do see a 'DMIC_DEVICE_ID'
0xAE20, this is not related to PCI and that's not what is used to probe
a driver.

if you are looking at Windows, the string you want to look for starts
with 'CTLR_DEV_', not 'DEV_'

> Now the interesting thing is that booting into linux and using lspci and
> lsusb, I cannot see a single device with the above specifications:
> 
> lspci:
> root at sakefilet /usr/src/git/linux/Documentation # lspci

[...]

> 00:1f.3 Multimedia audio controller: Intel Corporation Comet Lake PCH-LP cAVS

This is the one you want details on. please share the results of:

cat /sys/bus/pci/devices/0000\:00\:1f.3/device
cat /sys/bus/pci/devices/0000\:00\:1f.3/class

and sudo lspci  -vvv -s 00:1f.3