From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262700AbVBYOgP (ORCPT ); Fri, 25 Feb 2005 09:36:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262708AbVBYOgP (ORCPT ); Fri, 25 Feb 2005 09:36:15 -0500 Received: from pentafluge.infradead.org ([213.146.154.40]:50610 "EHLO pentafluge.infradead.org") by vger.kernel.org with ESMTP id S262700AbVBYOgM (ORCPT ); Fri, 25 Feb 2005 09:36:12 -0500 Subject: Re: [PATCH] I2C patch 5 - Add a non-blocking interface to the I2C core (again) From: Arjan van de Ven To: Corey Minyard Cc: lkml In-Reply-To: <421F35AB.2040305@acm.org> References: <421F35AB.2040305@acm.org> Content-Type: text/plain Date: Fri, 25 Feb 2005 15:36:07 +0100 Message-Id: <1109342168.6290.59.camel@laptopd505.fenrus.org> Mime-Version: 1.0 X-Mailer: Evolution 2.0.2 (2.0.2-3) Content-Transfer-Encoding: 7bit X-Spam-Score: 4.1 (++++) X-Spam-Report: SpamAssassin version 2.63 on pentafluge.infradead.org summary: Content analysis details: (4.1 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.3 RCVD_NUMERIC_HELO Received: contains a numeric HELO 1.1 RCVD_IN_DSBL RBL: Received via a relay in list.dsbl.org [] 2.5 RCVD_IN_DYNABLOCK RBL: Sent directly from dynamic IP address [80.57.133.107 listed in dnsbl.sorbs.net] 0.1 RCVD_IN_SORBS RBL: SORBS: sender is listed in SORBS [80.57.133.107 listed in dnsbl.sorbs.net] X-SRS-Rewrite: SMTP reverse-path rewritten from by pentafluge.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > +/* Another note: This interface is extremely sensitive to timing and > + failure handling. If you don't wait at least one jiffie after > + starting the transaction before checking things, you will screw it > + up. If you don't wait a jiffie after the final check, you will > + screw it up. If you screw it up by these manners or by abandoning > + an operation in progress, the I2C bus is likely stuck and won't > + work any more. Gotta love this hardware. */ this sounds scary. Your "jiffie" in the comment, for which value of HZ is that taken? Would you consider changing this to absolute time instead?