Re: pcm512x driver: Mixer control naming issue

[Howard Mitchell <hm@hmbedded.co.uk>]

On 16/03/15 11:38, Mark Brown wrote:
> On Sun, Mar 15, 2015 at 10:28:01PM +0000, Howard Mitchell wrote:
>
>> Defining a new prefix sounds like a reasonable idea in principle but calling
>> it "Analog(ue)" seems like it's saying this is a proper analogue volume
>> control whereas these particular controls merely provide very limited
>> selections of gain. I could imagine that at some point in the future a
> Userspace can determine how much control there is from the TLV
> information.  Ideally a smart userspace will manage to combine all the
> different controls it finds to make the best use it can of them - if it
> can use analogue volume control for some of the control that's generally
> better since it maximizes the resolution of the digital parts.

Makes sense.
>> default for "Analogue Playback Volume" may well be added to "alsactl
>> restore" and then we end up back in the same situation. How about defining a
>> prefix that is documented as saying that a default should not be used if
>> there's nothing in asound.state for that control?
> Really the problem here is using asound.state - it's far too dumb a
> means of controlling random cards, and attempting to change it is most
> likely going to break something else.  Any attempt to introduce a
> default for analogue control will inevitably result in problems on cards
> that currently work fine with digital/default control unless those are
> changed which would then cause problems for things without the analogue
> control.
So it sounds like adding an analogue prefix should be fairly safe in
which case are you happy for me to go ahead and prepare a patch?

- Howard