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Message-ID: <e4d3d21cdfe94068c76ceb4ba38630d76fa9418c.camel@suse.com>
Subject: Re: [PATCH 3/4] USB: serial: add support for multi-interface
 functions
From:   Oliver Neukum <oneukum@suse.com>
To:     Johan Hovold <johan@kernel.org>
Cc:     Mauro Carvalho Chehab <mchehab+huawei@kernel.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Wed, 31 Mar 2021 09:08:07 +0200
In-Reply-To: <YGNCIT1ocatZ3V3/@hovoldconsulting.com>
References: <20210330143820.9103-1-johan@kernel.org>
         <20210330143820.9103-4-johan@kernel.org>
         <e0b2984e7de0287c5811a10faaac4d5d6d7d91ef.camel@suse.com>
         <YGNCIT1ocatZ3V3/@hovoldconsulting.com>
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Am Dienstag, den 30.03.2021, 17:22 +0200 schrieb Johan Hovold:
> On Tue, Mar 30, 2021 at 04:44:32PM +0200, Oliver Neukum wrote:
> > Am Dienstag, den 30.03.2021, 16:38 +0200 schrieb Johan Hovold:
> > > @@ -1115,6 +1161,8 @@ static void usb_serial_disconnect(struct usb_interface *interface)
> > >         if (serial->type->disconnect)
> > >                 serial->type->disconnect(serial);
> > >  
> > > +       release_sibling(serial, interface);
> > > +
> > >         /* let the last holder of this object cause it to be cleaned up */
> > >         usb_serial_put(serial);
> > >         dev_info(dev, "device disconnected\n");
> > 
> > Hi,
> > 
> > does this assume you are called for the original interface first?
> 
> No, I handle either interface being unbound first (e.g. see
> release_sibling()).
> 
> > I am afraid that is an assumption you cannot make. In fact, if somebody
> > is doing odd things with sysfs you cannot even assume both will see a
> > disconnect()
> 
> Right, but disconnect() will still be called also for the sibling
> interface as part of release_sibling() above.

OK, sorry I overlooked that.

	Regards
		Oliver