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Date: Wed, 23 Nov 2011 22:00:02 +0000
From: Alan Cox <alan@linux.intel.com>
To: Oliver Neukum <oliver@neukum.org>
Cc: Havard Skinnemoen <hskinnemoen@google.com>, Jiri Slaby <jslaby@suse.cz>,
        Dave Jones <davej@redhat.com>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        "Greg Kroah-Hartman" <gregkh@suse.de>,
        Jiri Slaby <jirislaby@gmail.com>
Subject: Re: [RFC] cdc-acm: Fix potential deadlock (lockdep warning)
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On Wed, 23 Nov 2011 20:34:24 +0100
Oliver Neukum <oliver@neukum.org> wrote:

> Am Mittwoch, 23. November 2011, 20:22:33 schrieb Alan Cox:
> > and on the open side they provide their own install() method which
> > nicely avoids all the nasty locking problems and lets them use the
> > standard tty_port_open/close/hangup etc rather than the partial
> > ones.
> > 
> > It might be worth turning the ACM driver to work the same way as
> > it'll save doing that work later to achieve the same use of
> > tty_port_open/close/..
> > 
> > The main thing is the use of install - which lets you plug the USB
> > and tty bits together during the lookup of the device.
> 
> Which driver is the best example?

All the usb-serial drivers use the same core usb-serial.c to manage
all these bits. They just plug in additional I/O methods. So just look
at usb-serial.c