Comment 40 for bug 939161

> >
> > the real cases are those desktop which does not use hda front audio
panel ,
> > they just loss the auto mute since there is no jack detect circuit but
they
> > can still hear sound from the headphone at anytime
> >
> > do pulseaudio need a phantom port for the front panel headphone and mic
> > without jack detection ?
>
> Actually this is one good point.
> The jack detection isn't always reliably on such old machines, and
> BIOS cannot know, too. That is, it has to be adjusted by user
> manually, whether the jack detection is enabled or not.
>
> So far, we solved this by providing "Auto-Mute Mode" mixer switch.
> But the jack detection controls don't follow this yet. Maybe we can
> set such a jack control as inactive state when the jack detection is
> disabled.
>
> (And this reminds me that we can cut off "Phantom" name hack by
> following the same rule -- just set the control inactive when it has
> no real detection. But it still appears in control list.)
>
>

The other case is the bios of some computers with alc880 codec have pin
defaults 0x00000000
for some pin complexes

https://bugs.launchpad.net/ubuntu/+source/alsa-driver/+bug/1015232

hda jack detect need pin fixup

Pin Default 0x00000000: [Jack] Line Out at Ext N/A
    Conn = Unknown, Color = Unknown
    DefAssociation = 0x0, Sequence = 0x0

http://git.kernel.org/?p=linux/kernel/git/tiwai/sound.git;a=commit;h=67b6ec3196da235317ff1b9474f17379b78f3294