From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guenter Roeck Subject: Re: [PATCH] i2c/busses: Driver for Devantech USB-ISS I2C adapter Date: Tue, 22 Mar 2011 21:25:07 -0700 Message-ID: <20110323042507.GA9173@ericsson.com> References: <1300851827-13627-1-git-send-email-guenter.roeck@ericsson.com> <20110323034524.GA11675@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Return-path: Content-Disposition: inline In-Reply-To: <20110323034524.GA11675-U8xfFu+wG4EAvxtiuMwx3w@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Greg KH Cc: Jean Delvare , Ben Dooks , Randy Dunlap , "linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-doc-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" List-Id: linux-i2c@vger.kernel.org On Tue, Mar 22, 2011 at 11:45:24PM -0400, Greg KH wrote: > On Tue, Mar 22, 2011 at 08:43:47PM -0700, Guenter Roeck wrote: > > This patch adds support for the I2C interface of the Devantech USB-ISS > > Multifunction adapter. > > > > Signed-off-by: Guenter Roeck > > --- > > The driver has one problem: It competes with the cdc_acm driver for device > > access. Copying the usb mailing list in the hope that someone can tell me > > if there is a way to prevent this from happening. > > Why does it "compete"? > Is it because this driver also exposes a cdc-acm class interface? Why I guess so. > is it doing that if it doesn't follow that spec? We do already support I don't know if it follows the cdc-acm specification or not, though I would think it does since the cdc-acm driver recognizes it. I do see the "This device cannot do calls on its own. It is not a modem." message. I suspect the device exposes the cdc-acm class interface because it is a convenient means to make it show up as COM port in Windows. But I am not associated with the manufacturer, so that is just a wild guess. If it does follow the cdc-acm specification, does that help me anything ? > a number of "quirks" in the cdc-acm driver, I don't see why we couldn't > add a "blacklist this device" one there as well to help you out here if > it's needed. > Maybe, but only as last resort. Thanks, Guenter