From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755906AbXD0Otd (ORCPT ); Fri, 27 Apr 2007 10:49:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755914AbXD0Otd (ORCPT ); Fri, 27 Apr 2007 10:49:33 -0400 Received: from outbound-fra.frontbridge.com ([62.209.45.174]:36049 "EHLO outbound1-fra-R.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755906AbXD0Otb (ORCPT ); Fri, 27 Apr 2007 10:49:31 -0400 X-BigFish: VP X-Server-Uuid: 5FC0E2DF-CD44-48CD-883A-0ED95B391E89 Date: Fri, 27 Apr 2007 08:49:49 -0600 From: "Jordan Crouse" To: "Jean Delvare" cc: "Lennart Sorensen" , "Haavard Skinnemoen" , "David Brownell" , "Bryan Wu" , "Andrew Morton" , "Deepak Saxena" , linux-kernel@vger.kernel.org, "Christer Weinigel" Subject: Re: Bitbanging i2c bus driver using the GPIO API Message-ID: <20070427144949.GD28203@cosmic.amd.com> References: <20070419205942.GC5577@csclub.uwaterloo.ca> <20070420194933.0813a359@hyperion.delvare> <20070422154151.GJ5575@csclub.uwaterloo.ca> <20070423114254.71787844@hyperion.delvare> <20070423144710.GD1372@cosmic.amd.com> <20070426145634.3ac2b7a3@hyperion.delvare> <20070426132905.GP5575@csclub.uwaterloo.ca> <20070426133920.GA25456@cosmic.amd.com> <20070426140323.GE5577@csclub.uwaterloo.ca> <20070427100204.403d068c@hyperion.delvare> MIME-Version: 1.0 In-Reply-To: <20070427100204.403d068c@hyperion.delvare> User-Agent: Mutt/1.5.13 (2006-08-11) X-OriginalArrivalTime: 27 Apr 2007 14:49:16.0269 (UTC) FILETIME=[3A6B89D0:01C788DB] X-WSS-ID: 6A2CD2E71GC695297-02-01 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On 27/04/07 10:02 +0200, Jean Delvare wrote: > On Thu, 26 Apr 2007 10:03:23 -0400, Lennart Sorensen wrote: > > On Thu, Apr 26, 2007 at 07:39:20AM -0600, Jordan Crouse wrote: > > > There is no ISA on the LX. > > > > Isn't LPC a good equivalent? > > I suspect that Jordan meant that there is no LPC either. In which case, > of course, there's no way scx200_acb will ever work on that system, and > GPIO-based bitbanging is the way to go. Just using i2c-gpio rather than > scx200_i2c. This is getting confusing... :) On the sc1200 and and GX1, the ACB bus is accessed through ISA ports. There is no ISA on the cs5535/cs5536 companion chips (accompanying the GX and LX processors), and the ACB is accessed through PCI. All the platforms have LPC, but that really doesn't matter for the purposes of this discussion. The silicon block that implements the ACB has been generally unchanged over the last 6 or 7 years, so the same driver should support any of the platforms, assuming one can invoke the magic spells to get at the hardware. Jean and I have been concentrating most of our effort on getting the GX and LX to work through PCI, and really haven't concentrated our efforts on the older processors. Thats not to say it won't work, but its probably not plug and play. Jordan -- Jordan Crouse Senior Linux Engineer Advanced Micro Devices, Inc.