From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner+w=401wt.eu-S1761481AbZE1HwW@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1761481AbZE1HwW (ORCPT <rfc822;w@1wt.eu>);
	Thu, 28 May 2009 03:52:22 -0400
Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755366AbZE1HwO
	(ORCPT <rfc822;linux-kernel-outgoing>);
	Thu, 28 May 2009 03:52:14 -0400
Received: from gate.crashing.org ([63.228.1.57]:39242 "EHLO gate.crashing.org"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1754772AbZE1HwO (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Thu, 28 May 2009 03:52:14 -0400
Subject: Re: [RFC] [PATCH] Device Tree on ARM platform
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Robert Schwebel <r.schwebel@pengutronix.de>
Cc: Grant Likely <grant.likely@secretlab.ca>,
       devicetree-discuss <devicetree-discuss@ozlabs.org>,
       Russell King - ARM Linux <linux@arm.linux.org.uk>,
       Janboe Ye <yuan-bo.ye@motorola.com>, linux-kernel@vger.kernel.org,
       Timur Tabi <timur@freescale.com>, Jon Smirl <jonsmirl@gmail.com>,
       Scott Wood <scottwood@freescale.com>,
       linux-arm-kernel@lists.arm.linux.org.uk
In-Reply-To: <20090527235704.GQ6805@pengutronix.de>
References: <ed82fe3e0905270739k38018c87ka11f62c5977e45fb@mail.gmail.com>
	 <20090527150527.GK6805@pengutronix.de> <87vdnm8sec.fsf@macbook.be.48ers.dk>
	 <4A1D6901.2090508@freescale.com>
	 <20090527175609.GB31861@flint.arm.linux.org.uk>
	 <4A1D8FBA.6040802@freescale.com>
	 <9e4733910905271213k7f4b93e7i7e6f2af24d85f@mail.gmail.com>
	 <20090527192116.GA31110@n2100.arm.linux.org.uk>
	 <20090527193927.GD30039@game.jcrosoft.org>
	 <fa686aa40905271322x2f62c3dcs355374b30b4db3ca@mail.gmail.com>
	 <20090527235704.GQ6805@pengutronix.de>
Content-Type: text/plain
Date: Thu, 28 May 2009 17:48:45 +1000
Message-Id: <1243496925.3171.151.camel@pasglop>
Mime-Version: 1.0
X-Mailer: Evolution 2.26.1 
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Thu, 2009-05-28 at 01:57 +0200, Robert Schwebel wrote:
> On Wed, May 27, 2009 at 02:22:50PM -0600, Grant Likely wrote:
> > 2) Driver binding mechanism:  device tree nodes usually have a
> > "compatible" property which is a list of strings. The first string
> > describes exactly what the device is (ie. "atmel,24c08") and an
> > optional list of other devices which it is register interface
> > backwards compatible with.
> 
> This is a good example. The "exact" description above doesn't say
> anything about some of the details the driver needs to know. Here is the
> at24 driver:
> 
> http://lxr.linux.no/linux+v2.6.29/include/linux/i2c/at24.h#L18
> 
> Where do we get the page size & flags from?

Easy, add properties for them in the node for that device ! The
device-tree actually makes that really easy, a lot easier than anything
else I've seen so far.

Cheers,
Ben.