[pulseaudio-discuss] [RFC 2/2] bluetooth: Rank profiles based on available flag

[Tanu Kaskinen]

On Mon, 2013-11-18 at 16:20 +0200, Luiz Augusto von Dentz wrote:
> Hi Tanu,
> 
> On Mon, Nov 18, 2013 at 9:36 AM, Tanu Kaskinen
> <tanu.kaskinen at linux.intel.com> wrote:
> > On Tue, 2013-11-12 at 13:02 +0200, Luiz Augusto von Dentz wrote:
> >> diff --git a/src/modules/bluetooth/module-bluetooth-policy.c b/src/modules/bluetooth/module-bluetooth-policy.c
> >> index 4a90db7..864d10d 100644
> >> --- a/src/modules/bluetooth/module-bluetooth-policy.c
> >> +++ b/src/modules/bluetooth/module-bluetooth-policy.c
> >> @@ -137,21 +137,22 @@ static pa_card_profile *find_best_profile(pa_card *card) {
> >>      void *state;
> >>      pa_card_profile *profile;
> >>      pa_card_profile *result = card->active_profile;
> >> -    pa_card_profile *off;
> >> -
> >> -    pa_assert_se(off = pa_hashmap_get(card->profiles, "off"));
> >>
> >>      PA_HASHMAP_FOREACH(profile, card->profiles, state) {
> >> -        if (profile->available == PA_AVAILABLE_NO || profile == off)
> >> +        if (result == profile)
> >> +            continue;
> >> +
> >> +        if (profile->available > result->available) {
> >
> > "Unknown" is defined as 0 and "no" is defined as 1, so "no" will be
> > preferred over "unknown", which is probably not what you intended.
> 
> Now I figure why the checks for available was done in such way, still
> there is no point in disregard 'off' profile like the was doing as in
> 99% of the time it is the best/most available profile in the
> circumstances where find_best_profile is called.

I think there is a point in prioritizing "off" below other profiles
whose state is unknown. There are three transport states: disconnected,
connected and playing. You are saying that when the transport state
changes from playing to connected, then we should change the card
profile to off. I think this is a very bad idea. Let's say you're
playing music to a BT sink. Then you pause the music, the stream gets
corked, the sink gets suspended. When the sink suspends, the transport
is released and the transport state changes from playing to connected.
In your proposal, pausing the music player changes the BT card profile
to off, forcing rerouting (or killing) of the music stream.

-- 
Tanu