[alsa-devel] [RFC] Initialize volumes of HD-audio slave ctls

[Raymond Yau]

2012/3/9, Takashi Iwai <tiwai at suse.de>:
> At Fri, 9 Mar 2012 07:04:23 +0800,
> Raymond Yau wrote:
>>
>> 2012/3/8, Takashi Iwai <tiwai at suse.de>:
>> > Hi,
>> >
>> > the patch below is an attempt to initialize the volume / mutes of
>> > slave controls (such as "Headphone", "Speaker") with vmaster in
>> > HD-audio, so that the sound can come out only by changing the master
>> > volume/mute.
>> >
>> > We have thought that such initializations could be done well in
>> > alsactl init, but it seems that not everyone installs the latest and
>> > greatest alsactl, and there is always a risk that any new controls may
>> > be added before alsactl is updated and released.  Since the master
>> > volume is set muted, the risk by this change should be low.
>> >
>> > patch_cirrus.c still doesn't support this because it's handling
>> > vmaster by itself, but it can be fixed later, too.
>> >
>> > If anyone has a concern by this, please let me know.
>> >
>>
>> Can you explain the dB calculation of the volume controls when there
>> is a "virtual master" ?
>>
>> The Documentation only mention that all the slaves must have the same dB
>> range
>
> Well, more exactly, it'd work if the volume step is the same and the
> volume range of the first slave covers the all range.
>
>

patch_analog.c current only use DAC1

Is there any reason not to use DAC0 for ad1884 and ad1984 ?

This allow a separate volume control for "Headphone" and "Speaker"