Re: [Bluez-users] ACL connection handle

Marcel Holtmann
2008-03-26T16:27:38Z

Hi Brad,

>> I am using the infineon.When I play through the uart, I will give
>> -D
>> bluetooth option to aplay and this will create an acl as well as
>> sco
>> connection and route audio through uart.But if I am using the pcm
>> interface
>> , I will route audio to the pcm interface on the host connected
>> to the bt
>> module and use aplay without the bluetooth option right?,So I have
>> to create
>> an acl connection and then use the hcitool cmd to switch the SCO
>> interface
>> before I do aplay .So is that necessary to give the command from
>> inside the
>> audio service ?How would I establish the acl connection? Can I use
>> rfcomm
>> connect ?
>
> The bt alsa plugin does only make sense when getting audio over hci,
> but the audio service was designed so you could use d-bus to make it
> negotiate the connection and then get the audio through another route,
> eg the pcm.
>
> You could run the bluetooth negotiation yourself when going through
> pcm, but it would be better use of the infrastructure to patch the
> audio service so it can be used for both the pcm and hci cases. iirc,
> the audio service assumes you'll use one kind of routing the whole
> time you run it, so that would have to be changed to be a runtime
> setting set through d-bus.
>
> The audio service might be patched to, for example, invoke an external
> program between establishing the acl and sco connections. that could
> take an acl handle and do the infineon magic.
>
> I'm not sure there is a way to pull this off in a way that Marcel
> would accept upstream, but even if you have to do a custom patch to
> the audio service to make it work the way you need it I think you'll
> be able to pull it together more quickly.

shouldn't be a big problem, but in general this belongs into the
kernel since userspace is not dealing with ACL and SCO/eSCO connection
handling.

Regards