From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f48.google.com ([74.125.82.48]:34590 "EHLO mail-wm0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754244AbcASXuh (ORCPT ); Tue, 19 Jan 2016 18:50:37 -0500 Received: by mail-wm0-f48.google.com with SMTP id u188so164143207wmu.1 for ; Tue, 19 Jan 2016 15:50:36 -0800 (PST) Subject: Re: ID conflict between bdc_pci and "720p FaceTime HD Camera" To: Bjorn Helgaas References: <569BB4C2.3020602@gmail.com> <20160119225806.GA1841@localhost> Cc: linux-pci@vger.kernel.org, Ashwini Pahuja , Felipe Balbi From: Xavier Gnata Message-ID: <569ECBC9.9090800@gmail.com> Date: Wed, 20 Jan 2016 00:50:33 +0100 MIME-Version: 1.0 In-Reply-To: <20160119225806.GA1841@localhost> Content-Type: text/plain; charset=windows-1252; format=flowed Sender: linux-pci-owner@vger.kernel.org List-ID: On 19/01/2016 23:58, Bjorn Helgaas wrote: > [+cc Ashwini, Felipe] > > On Sun, Jan 17, 2016 at 04:35:30PM +0100, Xavier Gnata wrote: >> Hello, >> >> The development of a driver for >> 02:00.0 Multimedia controller [0480]: Broadcom Corporation 720p >> FaceTime HD Camera [14e4:1570] >> has started. It is still in an early stage but it's progressing and >> it already streams. >> https://github.com/patjak/bcwc_pcie >> >> However, as you can see, this webcam shares the exact same ID as >> bdc_pci 0x1570 . >> >> Could we use e.g. PCI_CLASS in bdc_pci to avoid grabbing the webcam >> incorrectly? >> The FaceTime HD Camera has PCI_CLASS 0x048000 >> I hope that bdc_pci has another PCI_CLASS. >> Or maybe there is a better way to distinguish bdc_pci from FaceTime >> HD Camera. What do you think? > > This is what the PCI Vendor/Device IDs are for. It's a shame that > Broadcom apparently screwed up and used the same IDs in two different > devices. > > At least, I *assume* they're different. I can't really tell what the > bdc_pci driver does, so it's conceivable that it's using the same > device in a different way than you are. > > If they really are different devices, using the class code sounds like > a reasonable way to differentiate them. > > Bjorn > bdc is "Broadcom's USB3.0 device controller IP" in the SOC world which is connected through PCIe on FPGA-PCIe based platform. Nothing to do with the Facetime HD webcam of a macbook air. Broadcom screwed up. The issue is that I don't have access to such a BDC. I also don't find it in http://pcidatabase.com/vendor_details.php?id=767 which lists 0x1570 as being the webcam. Where can we find the PCI class of this "Broadcom's USB3.0 device controller IP" ? Ashwini? Xavier