[pulseaudio-discuss] [PATCH] [module-loopback] Add new arguments sink_dont_move and source_dont_move to toggle module automatic unloading when the sink or source were not available

[Colin Guthrie]

'Twas brillig, and pl bossart at 03/01/11 18:10 did gyre and gimble:
> On Thu, Dec 23, 2010 at 5:40 AM, Cai Yuanqing <yuanqing.cai at tieto.com> wrote:
>>    This patch add two new boolean arguments sink_dont_move and
>> source_dont_move into module-loopback,so we can make the module unloading
>> when the sink or source was unavailable.
>> To enable this feature we can do something like:
>>>>> load-module module-loopback source=bluez_source.00_22_A5_AA_BF_85
>>>>> sink=alsa_output.pci-0000_00_1b.0.analog-stereo source_dont_move=TRUE
>>
>> And you can just feel free to ignore these arguments.
> 
> I don't have any arguments against the source_dont_move, but I am
> concerned about the sink_dont_move part. You may want to listen to
> your music on speakers, headsets, HDMI, etc. Why would you restrict
> the playback to the sink selected when you loaded the module? I can
> see this interfering with the accessory management/audio policy, at
> least in Meego. Falling back to the default sink should not add any
> noises?

I don't think it does much harm. It's optional and not used by default,
so it shouldn't get in the way much (it's only a handful of lines).

I guess it may get more interesting if we can make the modules more
"idle" friendly.

Like maybe I always want to loopback my TV tuner card to my bluetooth
headset. Ideally I'd load module-loopback in some kind of script (e.g.
default.pa) and it would just sit waiting patiently for the bluetooth
headset to come alive at which point loopback would suddenly kick into
life as it's "sink" had appeared. Obviously module loopback doesn't do
that yet (it just unloads when it's sink is not available), but it's a
step in that direction should this functionality be desirable.

The alternative to making the module more smart in itself is to add an
intelligent "loader" module that can track configuration based on sink
and source names and then load/unload the modules accordingly when said
devices appear and disappear.


Col


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Colin Guthrie
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http://colin.guthr.ie/

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