Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932724AbaFLHzY (ORCPT ); Thu, 12 Jun 2014 03:55:24 -0400 Received: from mail-oa0-f50.google.com ([209.85.219.50]:59723 "EHLO mail-oa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932529AbaFLHzW (ORCPT ); Thu, 12 Jun 2014 03:55:22 -0400 MIME-Version: 1.0 In-Reply-To: <538EB81B.3090807@gmx.de> References: <1401452797-29521-1-git-send-email-lee.jones@linaro.org> <1401452797-29521-2-git-send-email-lee.jones@linaro.org> <20140530123656.GC2742@katana> <20140530133405.GB29731@lee--X1> <20140530174800.GA4917@katana> <20140530192516.GA4319@lee--X1> <20140531134805.GA3287@katana> <538C8A59.2070907@gmx.de> <538EB81B.3090807@gmx.de> Date: Thu, 12 Jun 2014 09:55:21 +0200 Message-ID: Subject: Re: [PATCH] i2c: Make I2C ID tables non-mandatory for DT'ed and/or ACPI'ed devices From: Linus Walleij To: Michael Lawnick Cc: Wolfram Sang , Grant Likely , Lee Jones , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linux-i2c@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 4, 2014 at 8:09 AM, Michael Lawnick wrote: > Am 03.06.2014 13:18, schrieb Linus Walleij: >> On Mon, Jun 2, 2014 at 4:29 PM, Michael Lawnick wrote: >>> >>> Am 02.06.2014 14:16, schrieb Linus Walleij: >> >> >>>> Is this really so useful on embedded systems? >>>> >>>> I was under the impression that this method was something used >>>> on say PC desktops with temperature monitors and EEPROMs >>>> on some I2C link on the PCB, usage entirely optional and fun >>>> for userspace hacks. >>>> >>> We use it for dynamic instantiating whole subsystems with multiplexers, >>> sensors, controllers in an embedded system. The device list is taken from >>> an >>> I2C eeprom which gets read on hotplug. >> >> >> Does this mean that you have stored the names (strings) that are used >> by the Linux kernel for identifying the devices into your EEPROM? >> >> That means that you have made the kernel-internal device driver names >> an ABI which is unfortunate :-/ >> >> This is one of the reasons to why we insist on device tree: OS neutral >> hardware description. > > The eeprom contains a device tree that is dynamically merged. That is a kind of way of saying "yes we made the kernel-internal driver named an ABI" I guess? Yours, Linus Walleij -- 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/