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 182FFDDF9E for ; Tue, 16 Oct 2007 06:53:16 +1000 (EST) Message-ID: <4713D150.2020806@freescale.com> Date: Mon, 15 Oct 2007 15:45:04 -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> <4713C57F.7060509@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: >> 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. > > Even that doesn't work. For example if a PCI device is probed which > registers an i2c bus; there needs to be a mechanism for the i2c layer > to know that an id is already spoken for, so once again there needs to > be a mechanism to map easily from id to device (or lack thereof). As long as all statically-assigned buses have their devices passed to i2c_register_board_info by platform code before the PCI device is probed, the i2c layer will hand out bus numbers that don't conflict. > Where user == system integrator or firmware engineer. ie. boards with > no-populate options which affect the numbering; changes to match the > silkscreening on the chassis when a common board is used by multiple > systems. It's a conceivable scenario. (Again; this is more relevant > to eth and serial devices than i2c). Sure, but I guess I don't see the problem with such a person editing the label property. The label property also gives more freedom in terms of which characters can be used in the description. Aliases could still be used when there's a higher level abstraction related to purpose, not identification. -Scott