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Date:   Fri, 21 Apr 2023 18:15:02 -0500
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To:     linux-bluetooth@vger.kernel.org
From:   Richard Greer <rg@braneaudio.com>
Subject: Is AVCTP Version Really 1.3?
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Hi,

I will start by saying that I am not a Bluetooth expert, but just getting started on Bluetooth development.

In looking at BlueZ 5.66, it seems that the version of AVCTP being reported is 1.3 (in avrcp_ct_record() in profiles/audio/avrcp.c) which corresponded with what is in doc/supported-features.txt (which looks like it was last updated several years ago).

On the BlueZ website there is an entry from 21 Aug, 2014 titled "Bluetooth 4.1 qualification for Tizen BlueZ" that says it was using AVCTP 1.4.

AVCTP version 1.3 was deprecated in July, 2013 and officially withdrawn on 1 Feb, 2023.

If I were to start working on a product that was going to have Bluetooth in it, I could not get it certified with AVCTP 1.3.  So, I was just sort of hoping that it was a version reporting issue (due to the Tizen BlueZ statement above about it using 1.4 8+ years ago) and not something that still needs to be developed.

Anyhow, if someone more familiar with Bluetooth on Linux can explain what is up with the AVCTP version, that would be greatly appreciated.


Thanks in advance,

Richard Greer