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 B360CC433E2 for ; Thu, 17 Sep 2020 12:55:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F10521734 for ; Thu, 17 Sep 2020 12:55:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727146AbgIQMz2 (ORCPT ); Thu, 17 Sep 2020 08:55:28 -0400 Received: from mailout11.rmx.de ([94.199.88.76]:54087 "EHLO mailout11.rmx.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727067AbgIQMwk (ORCPT ); Thu, 17 Sep 2020 08:52:40 -0400 Received: from kdin01.retarus.com (kdin01.dmz1.retloc [172.19.17.48]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mailout11.rmx.de (Postfix) with ESMTPS id 4BsbYM5NzYz41wt; Thu, 17 Sep 2020 14:16:39 +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 kdin01.retarus.com (Postfix) with ESMTPS id 4BsbY70kfGz2xhY; Thu, 17 Sep 2020 14:16:27 +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 14:16:05 +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 14:13:36 +0200 Message-ID: <20200917121338.10757-1-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: 20200917-141627-4BsbY70kfGz2xhY-0@kdin01 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 flags 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 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=-9.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 BA262C433E2 for ; Thu, 17 Sep 2020 12:18:22 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5A974208DB for ; Thu, 17 Sep 2020 12:18:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="JeZcsRxH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5A974208DB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arri.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:To:From: Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender :Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Owner; bh=tmT5jJvXJDPw5/E6aLEVjBe0XM6rKjfyCi6ZKlW4q+Q=; b=JeZcsRxHgcwdSE79TvlvxOvocL 4Cd3JJNrgM6YmJwm0sZSrGkB4P4v8Bc5cibnzMY+ObTLcozqmiy0hcRpiQ8w2BqSCCxeFlx8kziWF GfvjTFXPGUnQ7J+q60w1XNz/wxaOL093Mh1up41wiIduF6wDIUe9kU8Ik6gG5Eue6ezTBNSTxxlYt ZqBUy0t2Pm8kMfE35DLgVUUHAnaGnBXLjkLZV/fqNSeec3pgq3pyZRZA0DhyCLfrnNZCTli6uS4NQ PaKnUsE4P1lEyA2jMyAm5FIIbk1cKauMdkiasnMby7DqyoNxe4FnqIrx5M3bo4LIUVhrO4kXTX+cH VHOh6dyg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kIsqU-00021v-Dr; Thu, 17 Sep 2020 12:17:02 +0000 Received: from mailout11.rmx.de ([94.199.88.76]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kIsqQ-0001ya-DD for linux-arm-kernel@lists.infradead.org; Thu, 17 Sep 2020 12:17:00 +0000 Received: from kdin01.retarus.com (kdin01.dmz1.retloc [172.19.17.48]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mailout11.rmx.de (Postfix) with ESMTPS id 4BsbYM5NzYz41wt; Thu, 17 Sep 2020 14:16:39 +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 kdin01.retarus.com (Postfix) with ESMTPS id 4BsbY70kfGz2xhY; Thu, 17 Sep 2020 14:16:27 +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 14:16:05 +0200 From: Christian Eggers To: Oleksij Rempel , Shawn Guo , Sascha Hauer , Fabio Estevam Subject: [PATCH 0/3] i2c: imx: Fix handling of arbitration loss Date: Thu, 17 Sep 2020 14:13:36 +0200 Message-ID: <20200917121338.10757-1-ceggers@arri.de> X-Mailer: git-send-email 2.26.2 MIME-Version: 1.0 X-Originating-IP: [192.168.54.80] X-RMX-ID: 20200917-141627-4BsbY70kfGz2xhY-0@kdin01 X-RMX-SOURCE: 217.111.95.66 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200917_081658_566505_6F5F5F3E X-CRM114-Status: UNSURE ( 8.77 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, NXP Linux Team , Pengutronix Kernel Team , linux-i2c@vger.kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On my (noisy) system, I2C arbitration losses happen quite often. In it's current implementation, the IAL flags 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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel