Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755701Ab1CQVYy (ORCPT ); Thu, 17 Mar 2011 17:24:54 -0400 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:42878 "EHLO opensource2.wolfsonmicro.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1755664Ab1CQVYv (ORCPT ); Thu, 17 Mar 2011 17:24:51 -0400 Date: Thu, 17 Mar 2011 21:24:49 +0000 From: Mark Brown To: Greg KH Cc: Nicolas Pitre , Arnd Bergmann , andy.green@linaro.org, Linux USB list , lkml Subject: Re: RFC: Platform data for onboard USB assets Message-ID: <20110317212449.GO31411@opensource.wolfsonmicro.com> References: <20110311162759.GS1760@opensource.wolfsonmicro.com> <20110311163522.GA9291@kroah.com> <20110311164850.GT1760@opensource.wolfsonmicro.com> <20110311165642.GA9996@kroah.com> <20110311170807.GV1760@opensource.wolfsonmicro.com> <20110311172345.GA10876@kroah.com> <20110317201320.GB4035@kroah.com> <20110317201835.GM31411@opensource.wolfsonmicro.com> <20110317202614.GA3155@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110317202614.GA3155@kroah.com> X-Cookie: Be careful! Is it classified? User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1372 Lines: 29 On Thu, Mar 17, 2011 at 01:26:14PM -0700, Greg KH wrote: > On Thu, Mar 17, 2011 at 08:18:35PM +0000, Mark Brown wrote: > > It's going to be an off the shelf USB ethernet controller. I'd be > > astonished if the board-configurable device IDs weren't set from the > > same SEPROM that the MAC address is so it'd just show up as a generic > > chip of whatever kind. > Huh? All USB controllers you buy have the ability to set the vendor and > product id, so you should always be able to key off of that. > Isn't that the case here? They generally the same facility that includes the ability to set the MAC address so if one's not been provided it seems optimistic to expect the other. The way this is normally done is that the ethernet controller can be attached to a SEPROM which it reads when it powers on. This will contain a number of device configuration parameters, including the vendor IDs and the MAC address, which will be configured before the device makes itself available on the bus. If the system integrator has omitted the SEPROM then the device will come up with defaults, usually something like all zeros. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/