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

Raymond Yau superquad.vortex2 at gmail.com
Wed Feb 24 02:12:34 CET 2010


2010/2/23 Clemens Ladisch <clemens at ladisch.de>

> Lennart Poettering wrote:
> > On Sun, 21.02.10 12:01, Raymond Yau (superquad.vortex2 at gmail.com) wrote:
> > > However Simple Mixer API cannot know the subdevice number , you have to
> use
> > > control API ( the lower level API used by Simple Mixer API )
> >
> > Unfortunately there is no way from the simple mixer to the lower level
> > mixer.
>
> Often, there is no 1:1 correspondence between mixer elements and PCM
> devices.  Only mixer controls with interface PCM (not MIXER) have (sub-)
> device numbers, and at the moment this is used only for controls that
> are associated with the streams of hardware-mixing-capable cards.
>

But there is really 1:1 correspondence for HDA capture sudevices and the
control related to capturing

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

Card hw:1 'Intel'/'HDA Intel at 0xff9f4000 irq 22'
  Mixer name    : 'Analog Devices AD1988'
  Components    : 'HDA:11d41988'
  Controls      : 48
  Simple ctrls  : 26

Simple mixer control 'Capture',0
  Capabilities: cvolume cswitch
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 54
  Front Left: Capture 39 [72%] [0.00dB] [off]
  Front Right: Capture 39 [72%] [0.00dB] [off]
Simple mixer control 'Capture',1
  Capabilities: cvolume cswitch
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 54
  Front Left: Capture 39 [72%] [0.00dB] [off]
  Front Right: Capture 39 [72%] [0.00dB] [off]
Simple mixer control 'Capture',2
  Capabilities: cvolume cswitch
  Capture channels: Front Left - Front Right
  Limits: Capture 0 - 54
  Front Left: Capture 39 [72%] [0.00dB] [off]
  Front Right: Capture 39 [72%] [0.00dB] [off]


Simple mixer control 'Input Source',0
  Capabilities: cenum
  Items: 'Front Mic' 'Line' 'Mic' 'CD' 'Mix'
  Item0: 'Mic'
Simple mixer control 'Input Source',1
  Capabilities: cenum
  Items: 'Front Mic' 'Line' 'Mic' 'CD' 'Mix'
  Item0: 'Front Mic'
Simple mixer control 'Input Source',2
  Capabilities: cenum
  Items: 'Front Mic' 'Line' 'Mic' 'CD' 'Mix'
  Item0: 'Front Mic'

    control.28 {
        comment.access 'read write'
        comment.type BOOLEAN
        comment.count 2
        iface MIXER
        name 'Capture Switch'
        value.0 false
        value.1 false
    }
    control.29 {
        comment.access 'read write'
        comment.type INTEGER
        comment.count 2
        comment.range '0 - 54'
        comment.dbmin -5850
        comment.dbmax 2250
        iface MIXER
        name 'Capture Volume'
        index 1
        value.0 39
        value.1 39
    }
    control.30 {
        comment.access 'read write'
        comment.type BOOLEAN
        comment.count 2
        iface MIXER
        name 'Capture Switch'
        index 1
        value.0 false
        value.1 false
    }
    control.31 {
        comment.access 'read write'
        comment.type INTEGER
        comment.count 2
        comment.range '0 - 54'
        comment.dbmin -5850
        comment.dbmax 2250
        iface MIXER
        name 'Capture Volume'
        index 2
        value.0 39
        value.1 39
    }
    control.32 {
        comment.access 'read write'
        comment.type BOOLEAN
        comment.count 2
        iface MIXER
        name 'Capture Switch'
        index 2
        value.0 false
        value.1 false
    }
    control.33 {
        comment.access 'read write'
        comment.type ENUMERATED
        comment.count 1
        comment.item.0 'Front Mic'
        comment.item.1 Line
        comment.item.2 Mic
        comment.item.3 CD
        comment.item.4 Mix
        iface MIXER
        name 'Input Source'
        value Mic
    }
    control.34 {
        comment.access 'read write'
        comment.type ENUMERATED
        comment.count 1
        comment.item.0 'Front Mic'
        comment.item.1 Line
        comment.item.2 Mic
        comment.item.3 CD
        comment.item.4 Mix
        iface MIXER
        name 'Input Source'
        index 1
        value 'Front Mic'
    }
    control.35 {
        comment.access 'read write'
        comment.type ENUMERATED
        comment.count 1
        comment.item.0 'Front Mic'
        comment.item.1 Line
        comment.item.2 Mic
        comment.item.3 CD
        comment.item.4 Mix
        iface MIXER
        name 'Input Source'
        index 2
        value 'Front Mic'
    }







>
> Getting information about the mixer layout (like the nodes reported by
> HDA and USB devices) is on the TODO list; the only reason it isn't being
> implemented is lack of time.
>
>
> Regards,
> Clemens
>


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