From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6263DC43461 for ; Thu, 17 Sep 2020 12:57:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 28ECE206CA for ; Thu, 17 Sep 2020 12:57:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727153AbgIQM5p (ORCPT ); Thu, 17 Sep 2020 08:57:45 -0400 Received: from mailout11.rmx.de ([94.199.88.76]:34391 "EHLO mailout11.rmx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727121AbgIQM5c (ORCPT ); Thu, 17 Sep 2020 08:57:32 -0400 Received: from kdin02.retarus.com (kdin02.dmz1.retloc [172.19.17.49]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mailout11.rmx.de (Postfix) with ESMTPS id 4Bsbfd4kKVz41xp; Thu, 17 Sep 2020 14:21:13 +0200 (CEST) Received: from mta.arri.de (unknown [217.111.95.66]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by kdin02.retarus.com (Postfix) with ESMTPS id 4BsbfP0DJ3z2TTMr; Thu, 17 Sep 2020 14:21:01 +0200 (CEST) Received: from N95HX1G2.wgnetz.xx (192.168.54.80) by mta.arri.de (192.168.100.104) with Microsoft SMTP Server (TLS) id 14.3.408.0; Thu, 17 Sep 2020 14:20:39 +0200 From: Christian Eggers To: Oleksij Rempel , Shawn Guo , Sascha Hauer , Fabio Estevam CC: Pengutronix Kernel Team , NXP Linux Team , , , Subject: [PATCH 0/3] i2c: imx: Fix handling of arbitration loss Date: Thu, 17 Sep 2020 14:20:26 +0200 Message-ID: <20200917122029.11121-1-ceggers@arri.de> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 Content-Transfer-Encoding: 7BIT Content-Type: text/plain; charset=US-ASCII X-Originating-IP: [192.168.54.80] X-RMX-ID: 20200917-142101-4BsbfP0DJ3z2TTMr-0@kdin02 X-RMX-SOURCE: 217.111.95.66 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On my (noisy) system, I2C arbitration losses happen quite often. In it's current implementation, the IAL flag is partly handled, but has a number of shortcomings: 1. The driver runs unnecessarily in a timeout when waiting for an interrupt. 2. The driver performs 500 ms busy-waiting without any value. 3. Arbitration loss errors may be reported one transfer later than they occured. Best regards Christian