From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw01.freescale.net (az33egw01.freescale.net [192.88.158.102]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw01.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTP id ED24FDDF58 for ; Tue, 16 Oct 2007 06:03:15 +1000 (EST) Message-ID: <4713C57F.7060509@freescale.com> Date: Mon, 15 Oct 2007 14:54:39 -0500 From: Scott Wood MIME-Version: 1.0 To: Grant Likely Subject: Re: [PATCH 2/2] i2c: Add devtree-aware iic support for PPC4xx References: <200710151529.11485.sr@denx.de> <20071015163216.GA8127@gate.ebshome.net> <20071015185340.GB4474@loki.buserror.net> <4713BE5E.3030406@freescale.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Cc: Jean Delvare , linuxppc-dev@ozlabs.org, Stefan Roese , i2c@lm-sensors.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Grant Likely wrote: > On 10/15/07, Scott Wood wrote: >> For associating a device node with a human readable label, I'd >> prefer a "label" property in the device node, rather than doing it >> backwards with aliases. > > Here the corresponding problem; having to scan every device node to > make sure you don't assign a number already selected by another node > (in the case where one node is assigned a number and another is not). > Don't Do That(tm). If you use this mechanism, and an adapter node doesn't have a bus number, then it doesn't get to pre-register devices, but instead must use i2c_new_device. >>> As per your point below; if all the i2c devices are children of >>> the adapter, then yes you are right that the bus number doesn't >>> matter to the user. But it *does* matter for things like serial >>> and ethernet ports. >> And a label property would be great for that. :-) > > Not really; if the user needs to renumber devices; you don't want him > fiddling around in the hardware description. Why would the user renumber devices? > Just like the chosen node; an aliases describes logical constructs, > not physical ones. I don't think this is any different from the > linux,stdout-path property in chosen. Well, it's somewhat different in that stdout describes a usage of the device, not the identity. Still, I don't like linux,stdout-path. :-) At the very least it should be a phandle. -Scott