[alsa-devel] alsactl adds volume controls?

[Raymond Yau]

2010/10/1 Mark Brown <broonie at opensource.wolfsonmicro.com>

> On Thu, Sep 30, 2010 at 04:09:56PM +0100, Colin Guthrie wrote:
>
> > *shouldn't* use them, but at present it does and they *are* active and
> > used, so it's not an issue for me), the problem is rather one of setting
> > Master (not PCM) to 0% aka -46.5dB causes some kind of auto-mute that
> > cuts off all sound. It shouldn't do that. I've not muted it. I've set it
>
> Is this perhaps just an error in the TLV information - should it be
> flagging that the minimim gain is mute but isn't?
>


For hda codec , the amplifiers can be found at [Audio Output], [Audio Mixer]
and [Pin complex]

Also the codec specification define which step is 0dB  , number of step and
dB for each step

Some codec can even be connected to a hardware volume knob

It also explicitly define a mute switch, so I don't think there is reason to
assume the minimum dB value is equal to mute ( -infinite dB )

In this case, the driver seem need to make some adjustment when there is no
volume knob connected , you may need to find another user with the same
codec connected to a volume knob or peform some calibration to find out how
to make the adjustment