I've spent most of the day working with the jack detection patches and they seem to be shaping up. I just wanted to give you a rough overview of what they do to the PulseAudio you used to know. ;-) Basically they can be separated into three parts: 1) Core changes Along with the discussions at the desktop summit, a card now has a list of ports. Every port has an availability status (yes/no/unkown). Ports also have an array of profiles for which that port is relevant (e g digital ports are only relevant for digital profiles). Since the same port is now referenced from both the card and the sink, it has been turned into a reference counted object. I've also added this info to the cli (pacmd), but how to show the card ports and the port<->profile connection through the introspection API is still pending. When the availability status of a port is changed, a hook is fired. At the moment, only module-switch-on-connect listens to that. (Once Colin has made the priority lists policy thing, that would also listen, I assume.) 2) Changes in the alsa modules Here's where the toughest stuff happens. In order to be able to fill in the new structures, we have to probe all profile's paths at startup. In order for this not to take too long time (and to make sure we don't get more than one port entry for the same port), we now have a cache of probed paths. Therefore paths are now owned by the profile set, and since more than one path set can reference the same path, the path set now have a hashmap of paths instead of a linked list. 3) Jack input device implementation This part is the "controversial" part as the jack input devices that it builds should be deprecated according to Lennart. It's the only thing we currently have from the kernel though. The connection between a path and a input device is configured in the path file: [Jack_InputDevice] name = Front code = Microphone ...which basically means that the input device must support code SW_MICROPHONE_INSERT and that its name must have "Front" in it somewhere. So when an event comes in, the input device's path's port changes its availability status, which makes module-switch-on-connect change the current port (and sometimes profile). Piece of cake! -- David Henningsson, Canonical Ltd. http://launchpad.net/~diwic
