On Tuesday 24 November 2015 06:13:51 Tanu Kaskinen wrote: > On Sun, 2015-11-22 at 23:33 +1000, Jonathan Wilson wrote: > > I am trying to understand how sinks and sink inputs work. > > The code I am trying to figure out creates the following sinks: > > master_sink (external sink obtained from ALSA sink module via pa_namereq_get) > > raw_sink (created with the flat_volume_sink parameter of the > > pa_sink_new_data structure set to master_sink) > > voip_sink (created with the flat_volume_sink parameter of the > > pa_sink_new_data structure set to raw_sink) > > > > And the following sink inputs: > > aep_sink_input (created with the sink parameter of the > > pa_sink_input_new_data structure set to raw_sink and the origin_sink > > parameter of the pa_sink_input_new_data structure set to voip_sink) > > hw_sink_input (created with the sink parameter of the > > pa_sink_input_new_data structure set to master_sink and the origin_sink > > parameter of the pa_sink_input_new_data structure set to raw_sink) > > cs_call_sink_input (created with the sink parameter of the > > pa_sink_input_new_data structure set to voip_sink and the origin_sink > > parameter of the pa_sink_input_new_data structure set to 0) > > > > I then have some other code that feeds audio into the voip_sink sink > > Can someone tell me the pathway in which audio will go from the app through > > to being fed into master_sink (and from there into the hardware)? > > Which sinks and sink inputs will it pass through and in which order? > > > > What about if audio passes into the raw_sink sink, what path will it take > > through the code in that case? > > I guess this is Maemo or MeeGo, or possibly Sailfish? Yes, this is for Maemo system. > I have worked on those systems in the past, and this sounds very > familiar (and certainly not something that is in upstream). Could you > send /etc/pulse/system.pa? > > > And where should I be looking (e.g. specific callback functions on the > > sinks or sink inputs) for anything that might be doing any kind of > > processing on the audio? > > Are you looking for a way to do your own processing, or are you just > trying to understand what processing your device does and how? We are trying to understand how that Maemo pulseaudio code is working... -- Pali Rohár pali.rohar at gmail.com