From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932652Ab2KEPTm (ORCPT ); Mon, 5 Nov 2012 10:19:42 -0500 Received: from zoneX.GCU-Squad.org ([194.213.125.0]:5142 "EHLO services.gcu-squad.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932482Ab2KEPTk (ORCPT ); Mon, 5 Nov 2012 10:19:40 -0500 Date: Mon, 5 Nov 2012 16:19:20 +0100 From: Jean Delvare To: Mika Westerberg Cc: "Rafael J. Wysocki" , Linus Walleij , Mark Brown , Bjorn Helgaas , linux-kernel@vger.kernel.org, lenb@kernel.org, rafael.j.wysocki@intel.com, grant.likely@secretlab.ca, ben-linux@fluff.org, w.sang@pengutronix.de, mathias.nyman@linux.intel.com, linux-acpi@vger.kernel.org Subject: Re: [PATCH 2/3] spi / ACPI: add ACPI enumeration support Message-ID: <20121105161920.44e8e1cb@endymion.delvare> In-Reply-To: <20121105145315.GI24532@intel.com> References: <1351928793-14375-1-git-send-email-mika.westerberg@linux.intel.com> <20121105150326.3bbf69df@endymion.delvare> <1925265.4Cx64DgKbB@vostro.rjw.lan> <20121105145315.GI24532@intel.com> X-Mailer: Claws Mail 3.7.10 (GTK+ 2.24.7; x86_64-suse-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 5 Nov 2012 16:53:15 +0200, Mika Westerberg wrote: > On Mon, Nov 05, 2012 at 03:19:58PM +0100, Rafael J. Wysocki wrote: > > > > In the ACPI namespace we have device nodes and serial interfaces below them. > > In the above case we see that a single device node supports two different > > interfaces and in that case we probably should create two different > > struct i2c_adapter objects for the same ACPI device node. > > > > Mika, what do you think? > > I agree. > > Only problem I see is that then we have two I2C adapter devices with the > same ACPI ID (and hence the same i2c_client->name). I wonder what the I2C > core thinks about that. I2C core fears that you're mixing up everything ;) I2C adapter devices are struct i2c_adapter aka i2c-0, i2c-1 etc. i2c_client is for slave devices. There's nothing wrong with i2c_clients sharing ->name, that's even how device driver matching is achieved. The uniqueness of i2c_clients is on their bus_id which is the combination of i2c adapter number and slave address (e.g. 0-0050) i2c_adapter->name should, OTOH, be unique. In i2c bus drivers we usually append the base I/O address at the end of the name to guarantee that. ACPI will have to come up with something similar. -- Jean Delvare