Comment 28 for bug 1365769

 > strange that only have /dev/snd/hwC0D2

There is only one codec, and it has address 2. This is unusual, but not wrong. Just supply card and device arguments to hda-jack-sense-test: "sudo hda-jack-sense-test -c 0 -d 2".
That said, hda-jack-sense-test has a tendency to break from time to time, when the proc files add new stuff. So I'm not sure it works anyway. I should probably rewrite it to be more robust.