[alsa-devel] Internal Mics and Speakers not visible in PulseAudio

Raymond Yau superquad.vortex2 at gmail.com
Fri Jun 1 04:54:01 CEST 2012

2012/5/30 David Henningsson <david.henningsson at canonical.com>:
> On 05/30/2012 03:04 PM, Raymond Yau wrote:
>> I am afraid this does not work with desktop computer which has front
>> mic , internal mic, Line in ,CD (or stereo mix with those via hda
>> codecs)
>> With ubuntu 12.04 and unity ,  if I enable hda jack detect with my
>> ad198x on my desktop, sound  preference does not allow me to select
>> front mic since I am still using ac97 front panel (with no jack detect
>> circuit)
> In that case your BIOS should detect that you're using an ac'97 front panel
> and set the "no prescence detect" bit in the default pin config.
> The codec driver should then not create any jack at all, and PulseAudio
> would pick up 'Input Source' -> 'Front Mic' as a reason to have create a
> 'Front Mic' port.

The patched driver just create two jack detect controls for rear panel
jacks when BIOS set front audio panel type to AC97

There are difference for the system settings/sound in unity and gnome

In gnome session, the system settings/sound list the three hardcoded
ports (front mic, line and rear mic) instead of all the items in the
"Input source" / "Capture Source" controls ( There is no CD in HDA,
and no CD , stereo mix, aux, phone for my other sound cards with ac97

Is there any way to add back "Stereo Mix" to pulseaudio 's port ?

In unity session, the system settings/sound only list  the plugged jacks.

I think the usage of jack detect to select input source automatically
is broken for for those  motherboards which have three audio jacks in
rear panel and retask those pink and blue jacks for surround51 output.

The module-switch-on-available-port should check whether "Channel
mode' is 6 and exclude the result those jack detect of "rear mic" and
"line in" since they have been retasked for output

BTW, the ICH8 HDA controller support multi stream capturing and ad1988
has thee capture subdevices

arecord -l
card 1: Intel [HDA Intel], device 0: AD198x Analog [AD198x Analog]
  Subdevices: 3/3
  Subdevice #0: subdevice #0
  Subdevice #1: subdevice #1
  Subdevice #2: subdevice #2

what is the definition of "Mono Output" in pulseaudio ?

it is just the capability of the sound card to play mono  or have a
mono speaker with a specific volume control

My three other sound cards does support mono playback and mono capture

The system setting/sound in gnome session allow me to select "mono
duplex" but when it does not allow me to select "mono output + mono
input" in unity session.

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