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Date:   Tue, 5 Jul 2022 11:56:13 +0200
From:   Max Staudt <max@enpas.org>
To:     Marc Kleine-Budde <mkl@pengutronix.de>,
        Geert Uytterhoeven <geert@linux-m68k.org>
Cc:     Wolfgang Grandegger <wg@grandegger.com>, linux-can@vger.kernel.org,
        Vincent Mailhol <vincent.mailhol@gmail.com>,
        Oliver Neukum <oneukum@suse.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Vincent Mailhol <mailhol.vincent@wanadoo.fr>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Oliver Hartkopp <socketcan@hartkopp.net>
Subject: Re: [PATCH v9] can, tty: can327 CAN/ldisc driver for ELM327 based
 OBD-II adapters
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On Tue, 5 Jul 2022 11:49:27 +0200
Marc Kleine-Budde <mkl@pengutronix.de> wrote:

> On 05.07.2022 11:43:52, Geert Uytterhoeven wrote:
> > So development started before commit cd6484e1830be260 ("serdev:
> > Introduce new bus for serial attached devices").  I guess that is
> > the reason why this driver uses a line discipline, instead of the
> > serial bus?
> > 
> > I had a quick glance through the various revisions posted, and it
> > doesn't seem like anyone mentioned the serial bus.  Would there be
> > any advantage in migrating to the serial bus?  
> 
> Does serial bus work with hot plug devices like USB Serial Adapters
> and/or devices that are not described in the device tree?

This is indeed the reason. The device cannot be autodetected, as the
UART has no identifying information (USB VID/PID or the like, and don't
forget the BT variants) attached to it, hence the manual attachment.


Max