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Message-ID: <e885258a0b9a3ba15640553e9f002cdfc89f4b79.camel@hadess.net>
Subject: Re: Bluetooth printer connection error
From:   Bastien Nocera <hadess@hadess.net>
To:     Laurent Vivier <laurent@vivier.eu>, linux-bluetooth@vger.kernel.org
Date:   Wed, 09 Dec 2020 12:00:45 +0100
In-Reply-To: <3a6fa942-bec5-5e5f-391d-197d1c1eafa6@vivier.eu>
References: <3a6fa942-bec5-5e5f-391d-197d1c1eafa6@vivier.eu>
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On Tue, 2020-12-08 at 22:25 +0100, Laurent Vivier wrote:
> Hi,
> 
> TL;DR:
> 
> I can pair my bluetooth printer but it fails to connect:
> 
>   $ bluetoothctl connect DC:0D:30:90:23:C7
> 
>   Attempting to connect to DC:0D:30:90:23:C7
>   [CHG] Device DC:0D:30:90:23:C7 Connected: yes
>   [CHG] Device DC:0D:30:90:23:C7 ServicesResolved: yes
>   Failed to connect: org.bluez.Error.NotAvailable
> 
> What do I need to add to my system to have this working?

As I mentioned in the original bug:
https://bugzilla.redhat.com/show_bug.cgi?id=1904686

I don't expect the "connect" command to do anything. There's nothing to
"connect" to, as bluez doesn't create rfcomm device nodes automatically
when "connecting" to devices with serial profiles (otherwise one
couldn't connect to them with other applications without going through
the device node...).

If the printer has uses the SPP or HCRP printing profiles, you should
see it when using:
/usr/lib/cups/backend/bluetooth
without any arguments.

Otherwise any apps or driver that supports the printer should be able
to create a serial link directly to the device without creating a
device node in /dev.

FWIW, looks like the printer uses a proprietary protocol between their
own app and the printer, and that they don't provide Linux support.
Short of reverse engineering that protocol, the printer is unlikely to
work with Linux.

Cheers