From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751140AbWFLRNn (ORCPT ); Mon, 12 Jun 2006 13:13:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751487AbWFLRNn (ORCPT ); Mon, 12 Jun 2006 13:13:43 -0400 Received: from khc.piap.pl ([195.187.100.11]:26045 "EHLO khc.piap.pl") by vger.kernel.org with ESMTP id S1751140AbWFLRNm (ORCPT ); Mon, 12 Jun 2006 13:13:42 -0400 To: "Mark M. Hoffman" Cc: linux-kernel@vger.kernel.org, lm-sensors@lm-sensors.org Subject: Re: [lm-sensors] [PATCH] I2C: i2c_bit_add_bus should initialize SDA and SCL lines References: <20060609110546.GA26073@jupiter.solarsys.private> <20060612123626.GA27429@jupiter.solarsys.private> From: Krzysztof Halasa Date: Mon, 12 Jun 2006 19:13:38 +0200 In-Reply-To: <20060612123626.GA27429@jupiter.solarsys.private> (Mark M. Hoffman's message of "Mon, 12 Jun 2006 08:36:26 -0400") Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Hi, "Mark M. Hoffman" writes: > If you can't read the line state... well, that's not actually a proper > I2C bus anyway. Actually you only have to be able to read SDA state, it might not be true WRT SCL. I think most implementations use a single master and a fixed access timing and thus only read SDA (SCL can as well be a simple 2-state normal output from master instead of open drain/collector or 3-state). I'm not sure initializing the bus (in terms of ~ handshaking) belongs to hw driver and not to the algorithm but such is live. Thanks. -- Krzysztof Halasa