[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <Pine.LNX.4.44L0.0808271451550.17771-100000@iolanthe.rowland.org>
Date: Wed, 27 Aug 2008 14:58:08 -0400 (EDT)
From: Alan Stern <stern@...land.harvard.edu>
To: Greg KH <greg@...ah.com>, Oliver Neukum <oliver@...kum.org>
cc: USB list <linux-usb@...r.kernel.org>,
Stefan Kopp <stefan_kopp@...lent.com>,
Marcel Janssen <korgull@...e.nl>,
Felipe Balbi <me@...ipebalbi.com>,
Kernel development list <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] USB: add USB test and measurement class driver - round
2
On Wed, 27 Aug 2008, Greg KH wrote:
> On Wed, Aug 27, 2008 at 02:28:22PM -0400, Alan Stern wrote:
> > On Wed, 27 Aug 2008, Greg KH wrote:
> >
> > > Here's an updated version of the usbtmc driver, with all of the
> > > different issues that have been raised, hopefully addressed.
> >
> > This is an example of what I was discussing with Oliver. In all
> > likelihood you simply don't need usbtmc_mutex, and using it will cause
> > a lockdep violation.
> >
> > That's why so many of the other USB class drivers don't have an
> > analogous static mutex.
>
> Ok, then it's just safe to drop this static mutex entirely, right?
Yes, once you add the call to usb_deregister_dev.
On Wed, 27 Aug 2008, Oliver Neukum wrote:
> And this rule depends on sharing the USB major or not. This needs
> a big fat mention in Documentation.
You mean that the open/disconnect locking rule applies only to drivers
that call usb_register_dev, i.e, drivers using the USB major. Right?
I agree that it deserves to be mentioned in the documentation
somewhere. Where would be a good place? None of the existing files in
Documentation/usb seem appropriate.
Alan Stern
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists