[pulseaudio-discuss] [PATCH v5 3/4] bluetooth: add correct HFP rfcomm negotiation

[James Bottomley]

On Fri, 2017-09-22 at 21:09 +0300, Luiz Augusto von Dentz wrote:
> Hi James,
> 
> On Thu, Sep 21, 2017 at 10:28 PM, James Bottomley
> <James.Bottomley at hansenpartnership.com> wrote:
[...]
> > +static bool hfp_rfcomm_handle(int fd, pa_bluetooth_transport *t,
> > const char *buf)
> > +{
> > +    struct hfp_config *c = t->config;
> > +    int val;
> > +
> 
> Was this code tested against PTS or you just got it working with some
> specific headsets? Im guessing this is for SLC handling but Im afraid
> this was never really qualified properly so perhaps some statement
> here would be nice.
> 
> If you have no idea what Im talking about you please have a look at:
> 
> https://www.bluetooth.org/docman/handlers/DownloadDoc.ashx?doc_id=411
> 65

The site seems to be login protected, but if this is some type of
simulator, it would be useful to run it by that if you can get me
access.

> There may be commands we would need to implement even if the
> indicators are not supported to pass qualification. If this is just a
> 'works for me' solution then we better put a disclaimer about not
> using this code on Bluetooth certified products.

I can ask Marcel what the usual certification route of Linux code is,
if it's important.  I wasn't aware we'd put any pulseaudio code through
bluetooth qualifications before (unless the vendors just did it
quietly).

[...]
> > +    /*
> > +     * once we're fully connected, just reply OK to everything
> > +     * it will just be the headset sending the occasional status
> > +     * update, but we process only the ones we care about
> > +     */
> 
> Im not really sure responding "OK" to everything will do well for
> interoperability, some vendors uses HFP with the its own set of
> vendor commands which may not always accept OK as a response or it
> may trigger some special mode.

I modelled that on the android code

https://android.googlesource.com/platform/packages/apps/Bluetooth/+/master/src/com/android/bluetooth/hfp/HeadsetStateMachine.java

It responds OK to any vendor specific command it doesn't recognise.

James