[pulseaudio-discuss] [PATCH 2/8] card: Add variables for splitting up a profile

[David Henningsson]

On 2015-10-19 16:32, Tanu Kaskinen wrote:
> On Mon, 2015-10-19 at 16:11 +0200, David Henningsson wrote:
>>
>> On 2015-10-19 15:56, Tanu Kaskinen wrote:
>>> On Tue, 2015-05-05 at 17:01 +0200, David Henningsson wrote:
>>>> It can be useful for routing modules to know if a profile consists
>>>> of an output and input part, in order to e g change output profile
>>>> while keeping the input profile unchanged.
>>>
>>> n_sinks and n_sources already tell if a profile consists of an output
>>> and input part.
>>
>> It's not only *if* but also *what* the input and output parts are.
>
> Ok, so routing modules may want to know what particular sinks and
> sources the profile contains. Since a profile may contain multiple
> sinks or sources, I think the fields should contain all sink/source
> names, and not only one that is selected according to some unobvious
> logic.

Yes. Although more than one sink is currently not implemented (it leaves 
the field as NULL instead - see later patches).

> Currently the fields don't contain the actual sink/source name, but an
> alias (derived from the alsa mapping name) - are there good reasons to
> prefer an alias rather than the real sink/source name?

Consistency with the name field, I suppose. Or plain simplicity. I 
didn't really think of the option of using the real sink/source names 
instead.

The sink(s) are not created until the profile is activated, so I haven't 
checked if it's easy or difficult to use the sink/source names instead.

The idea is just to make it possible for a routing module to keep "the 
other side" unchanged - e g, when hdmi is unplugged and the routing 
module needs to swap to analog speakers (and thus an analog profile), it 
should try to select a profile which has the same input_name as the 
current one.

In the future maybe input_name/output_name can be improved and used for 
more things.

-- 
David Henningsson, Canonical Ltd.
https://launchpad.net/~diwic