Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752651Ab1DTGk0 (ORCPT ); Wed, 20 Apr 2011 02:40:26 -0400 Received: from mms2.broadcom.com ([216.31.210.18]:4268 "EHLO mms2.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751370Ab1DTGkZ convert rfc822-to-8bit (ORCPT ); Wed, 20 Apr 2011 02:40:25 -0400 X-Server-Uuid: D3C04415-6FA8-4F2C-93C1-920E106A2031 To: "Greg KH" cc: =?utf-8?B?UmFmYcWCIE1pxYJlY2tp?= , "Arnd Bergmann" , "George Kashperko" , "Hauke Mehrtens" , "Russell King" , "linux-kernel@vger.kernel.org" , "linux-wireless@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "Jonas Gorski" , "b43-dev@lists.infradead.org" , "Andy Botting" , "Larry Finger" Subject: Re: Could I (ab)use bus (struct bus_type) for virtual Broadcom bus? References: <1302892585.30441.12.camel@dev.znau.edu.ua> <201104171938.12834.arnd@arndb.de> <20110419140257.GA20456@kroah.com> Date: Wed, 20 Apr 2011 08:39:59 +0200 MIME-Version: 1.0 From: "Arend van Spriel" Organization: Broadcom Message-ID: In-Reply-To: <20110419140257.GA20456@kroah.com> User-Agent: Opera Mail/11.10 (Linux) X-WSS-ID: 61B05F0E3CK18458239-01-01 Content-Type: text/plain; charset=utf-8; format=flowed; delsp=yes Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1340 Lines: 40 On Tue, 19 Apr 2011 16:02:57 +0200, Greg KH wrote: > Please don't use a platform device, unless there is no other way for > your device to work. For this device, you are connected to the PCI bus, > so a platform device does not make sense at all. Hi Greg, This is only true for a particular usage model. There are two models as shown below: 1) PCI(e) card ........... +----------+ : x y z : x, y, and z are cores. | uC |__________:___|_|_| : | | PCI-bus : axi-bus : +----------+ :.........: bcm chipset 2) SoC ............... : uC x y z : : |____|_|_| : : axi-bus : :.............: bcm chipset Your statement is true for 1) but in usage model 2) there is no PCI bus. Also you refer to the chipset when you say 'device'. In the axi bus type each individual core is registered as a device in the linux device tree. Gr. AvS -- "The world is indeed comic, but the joke is on mankind." — H.P. Lovecraft -- 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/