Messages in this thread | | | Date | Wed, 27 Aug 2008 14:58:08 -0400 (EDT) | From | Alan Stern <> | Subject | Re: [PATCH] USB: add USB test and measurement class driver - round 2 |
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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
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