[alsa-devel] Verifying mixer dB data/Invalid dB data from USB cards, especially Aureon 5.1 MkII

[Raymond Yau]

2010/2/20 Jaroslav Kysela <perex at perex.cz>

> On Fri, 19 Feb 2010, Raymond Yau wrote:
>
>
>>>
>>>  PA assume every sound card can only record from one capture source at
>> the
>> same time (like those AC97 card )
>>
>> However HDA support multi streaming capture , the capture device 0 may
>> have
>> more than one subdevice "Capture sources"  depend on the codec and  device
>> 2  has 2 subdevice for capturing "Input sources" on some codec
>>
>> Is HDA_SUBDEV_NID_FLAG or any API for the application to find the correct
>> mixer control for these kind of capturing subdevices  ? ( simple mixer api
>> is not able to know the subdevice number )
>>
>
> This API is not implemented at the time.
>
>                                        Jaroslav
>


How did the current implementation of VIA Smart 5.1 and Independent HP mode
affect alsa application such as pulseaudio ?

There are two playback subdevices and driver is supposed to support 5.1
smartly when the speaker jack is plugged


But PA developer seem expect an "2 4 6 channels switch" in all HDA codec

**** List of PLAYBACK Hardware Devices ****

card 0: NVidia [HDA NVidia], device 0: VT1708S Analog [VT1708S Analog]
  Subdevices: 2/2
  Subdevice #0: subdevice #0
  Subdevice #1: subdevice #1

http://pulseaudio.org/ticket/743

https://bugtrack.alsa-project.org/alsa-bug/view.php?id=4895

seem bug in alsa driver for rear channels ?