Hi Per,
On Thu, Jan 17, 2019 at 9:19 AM Per Waagø <pwaago@xxxxxxxxx> wrote:
>
> We have a product that implements an A2DP sink running bluez 5.50. I'm
> try to qualify this product with the Bluetooth SIG using the Profile
> Tuning Suite (PTS), but I am having trouble passing a test that verifies
> reported delay value (A2DP/SNK/SYN/BV-01-C).
>
> In that test, PTS configures an AVDTP stream and verifies the delay
> report, then opens the stream, streams some data and closes the stream.
> This is repeated. The problem seems to be that after the stream is
> closed, bluez immediately also closes the L2CAP signaling channel.
>
> I have pasted the problematic sequence from btmon at the bottom of this
> email, the problem is the last L2CAP Disconnection request.
>
> This was introduced with commit 7ece89b0b6 between version 5.47 and
> 5.48. Before that, there was always a one second delay before the
> signaling channel was disconnected,
> which was enough for PTS to configure a new stream.
>
> What was the rationale for always disconnecting immediately? Could there
> be circumstances where it would make sense to keep the signaling channel
> open a bit longer? Is there any other way we can force the channel to
> stay open?
Could you please try to check with the patch Ive just sent? That
should track who has closed/aborted the stream so in case the remote
have done it will set a timeout before destroying the session.
> Best regards,
> Per Waagø
>
> --
> > ACL Data RX: Handle 12 flags 0x02 dlen 7 #329 [hci0]
> 48.732441
> Channel: 64 len 3 [PSM 25 mode 0] {chan 0}
> AVDTP: Close (0x08) Command (0x00) type 0x00 label 2 nosp 0
> ACP SEID: 1
> < ACL Data TX: Handle 12 flags 0x00 dlen 6 #330 [hci0]
> 48.732775
> Channel: 64 len 2 [PSM 25 mode 0] {chan 0}
> AVDTP: Close (0x08) Response Accept (0x02) type 0x00 label 2 nosp 0
> > ACL Data RX: Handle 12 flags 0x02 dlen 310 #331 [hci0]
> 48.736692
> > ACL Data RX: Handle 12 flags 0x01 dlen 337 #332 [hci0]
> 48.771536
> Channel: 65 len 643 [PSM 25 mode 0] {chan 1}
> > ACL Data RX: Handle 12 flags 0x02 dlen 12 #333 [hci0]
> 48.771963
> L2CAP: Disconnection Request (0x06) ident 30 len 4
> Destination CID: 65
> Source CID: 65
> < ACL Data TX: Handle 12 flags 0x00 dlen 12 #334 [hci0]
> 48.772019
> L2CAP: Disconnection Response (0x07) ident 30 len 4
> Destination CID: 65
> Source CID: 65
> < ACL Data TX: Handle 12 flags 0x00 dlen 12 #335 [hci0]
> 48.772960
> L2CAP: Disconnection Request (0x06) ident 4 len 4
> Destination CID: 64
> Source CID: 64
> > HCI Event: Number of Completed Packets (0x13) plen 5 #336 [hci0]
> 48.778131
> Num handles: 1
> Handle: 12
> Count: 2
> > HCI Event: Number of Completed Packets (0x13) plen 5 #337 [hci0]
> 48.953264
> Num handles: 1
> Handle: 12
> Count: 1
> > HCI Event: Disconnect Complete (0x05) plen 4 #338 [hci0]
> 50.167143
> Status: Success (0x00)
> Handle: 12
> Reason: Remote Device Terminated due to Power Off (0x15)
>
--
Luiz Augusto von Dentz
