On Wed, 2015-05-13 at 15:24 +0200, David Henningsson wrote: > > On 2015-05-13 12:06, Tanu Kaskinen wrote: > > On Wed, 2015-05-13 at 09:29 +0200, David Henningsson wrote: > >> Since many years ago we have an API for setting default source/sink. > >> > >> Our default routing today is more port centric. So our UIs (at least the > >> unity/gnome one) has developed ways around this, so that when a port is > >> selected it first selects the right profile if needed. > >> > >> The problem is that in this world it's becoming more difficult to detect > >> what the user actually wants, when the result is a chain of API calls. E > >> g, if we first get a "set profile" call, we're not certain whether this > >> is the user wanting to change the profile for the currently active port, > >> or if this is the first part of a transition to a new port. > > > > This problem description isn't really detailed enough for me to > > understand what you're trying to solve. > > Ok. Assume you have 2.1 speakers, and headphones without full jack > detection. (This is the case for some Dell laptops where the jack can be > both used as headphone, headset and just mic, and the hardware cannot > detect which one you plugged in.) > > Headphones are plugged in, and the user selects headphones manually. > > This causes the GUI to perform three calls to the API: > 1) Change profile to stereo (so that we have a profile that supports > headphones) > 2) Change port to headphones for the newly created sink. > 3) Change the default sink to the newly created one. > > Now, assuming we want to save profile per port, PA cannot in step 1 be > sure whether the user explicitly wanted to switch to a stereo profile > for the speakers, or whether the profile switch was just part of the > port switching. Thanks for the explanation! Now I understand what was the motivation for the new API, and the addition makes perfect sense. > >> To overcome this problem, we should have some new API enabling the UI to > >> set the port directly. E g like this: > >> > >> pa_set_card_port(card, port, profile, bool default) I suggest "pa_context_activate_port" or "pa_context_activate_card_port" as the function name. "pa_(context_)set_card_port" sounds like the card could only have one port active at a time. -- Tanu
