Kernel vs Userland AVDTP
Hi all,
Browsing the archives i've seen there has been some interest around the end of 2004 for an avdtp kernel implementation.
However recent trends seem to try to solve the issue in userland (Frederic's a2dpd or bluez's btaudiod for instance).
Is there a reason for this change of trends (except for "it's easier to have it done in user space for now" ;-) ) ?
Wouldn't it make more sense to have it in kernel due to multiplexing issues ?
Cheers,
Fabien
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Fabien
What are the multiplexing issues? Something like two apps trying to use the same remote device?
Having avdtp sockets offered by the os would enforce better separation between the layers and it would change the landscape for bluetooth.orgvalidation of the stack. It does feel sort of funny to write code to
assemble packets in userspace... maybe once we have something other than a2dp running on top of avdtp it will be even more compelling to change things.
Brad
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Marcel Holtmann
maintainerHi Fabien,
Quoted 11 lines
Browsing the archives i've seen there has been some interest around the end of 2004 for an avdtp kernel implementation.
However recent trends seem to try to solve the issue in userland (Frederic's a2dpd or bluez's btaudiod for instance).
Is there a reason for this change of trends (except for "it's easier to have it done in user space for now" ;-) ) ?
Wouldn't it make more sense to have it in kernel due to multiplexing issues ?
at some point, yes. Currently it makes no sense to start with a kernel version of AVDTP. Also Bluetooth 2.1 and 3.0 are gonna have high impact on L2CAP and I wanna have that settled first before considering a kernel based AVDTP, because it is not that simple. It would be as complex as RFCOMM and so keeping it in userspace is better for now.
Regards
Marcel
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Hi Marcel,
Quoted 6 lines
at some point, yes. Currently it makes no sense to start with a kernel version of AVDTP. Also Bluetooth 2.1 and 3.0 are gonna have high impact on L2CAP and I wanna have that settled first before considering a kernel based AVDTP, because it is not that simple. It would be as complex as RFCOMM and so keeping it in userspace is better for now.
I would tend to agree with you, specially on the fact that it would be quite complex to implement.
But what about a user space library? Do you thing that would make sense ?
Cheers,
Fabien
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