Received-SPF: pass (google.com: best guess record for domain of linux-bluetooth-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Content-Type: text/plain;
        charset=us-ascii
Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.11\))
Subject: Re: Yet another counterfeit CSR device?
From:   Marcel Holtmann <marcel@holtmann.org>
In-Reply-To: <CAEQQxWySUJZBa9CF7-W_4zXcuitgaNuu2f_pYswLKDUtVwWd1g@mail.gmail.com>
Date:   Tue, 30 Jul 2019 11:39:59 +0200
Cc:     linux-bluetooth@vger.kernel.org
Content-Transfer-Encoding: 8BIT
Message-Id: <A8776B75-52DF-47E9-9FE8-4C59F10109F5@holtmann.org>
References: <CAEQQxWySUJZBa9CF7-W_4zXcuitgaNuu2f_pYswLKDUtVwWd1g@mail.gmail.com>
To:     Andrey Batyiev <batyiev@gmail.com>
Sender: linux-bluetooth-owner@vger.kernel.org
Precedence: bulk

Hi Andrey,

> I have nontdescript usb bluetooth dongle with "V5.0" marking on it.
> It claims to be CSR (0a12:0001) bluetooth dongle, but it has
> nonfunctional "delete stored link key" command, so I think it is
> counterfeit.
> 
> Futhermore, Linux kernel doesn't detect it as counterfeit
> (in`btusb_setup_csr`), because the dongle reports following:
> 
> - From USB enumeration:
> bcdDevice = 0x8891
> 
> - From Read Local Version HCI command:
> Manufacturer = 0x000a (CSR)
> HCI ver. = 4.0
> HCI rev. = 2064
> LMP ver. = 4.0
> LMP subver. = 4114
> 
> So, Linux kernel fails to power up this dongle. Ok, so I've hacked
> `btusb_setup_csr` routine to include this device too (it powers up
> now), however GATT communication doesn't work (btmon should nothing =
> no ATT exchanges except MTU setup).
> 
> Any ideas on what should I check to make this device work?

please post a btmon -w trace.log from the init procedure. You might need to blacklist btusb.ko module and then manually load it to capture the whole sequence with btmon.

Regards

Marcel