From patchwork Thu May 6 01:10:11 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Packham X-Patchwork-Id: 431856 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=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 3C308C433B4 for ; Thu, 6 May 2021 01:10:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 193FE61132 for ; Thu, 6 May 2021 01:10:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229946AbhEFBLW (ORCPT ); Wed, 5 May 2021 21:11:22 -0400 Received: from gate2.alliedtelesis.co.nz ([202.36.163.20]:40354 "EHLO gate2.alliedtelesis.co.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229796AbhEFBLW (ORCPT ); Wed, 5 May 2021 21:11:22 -0400 Received: from svr-chch-seg1.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id B9056806B6; Thu, 6 May 2021 13:10:20 +1200 (NZST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1620263420; bh=QaVXYXC9HAPRyg9kDvGT+lsfZD0ND1BQRe4K8Jdr8M0=; h=From:To:Cc:Subject:Date; b=m7NejHDl1PGWc9qGDJgMllAMBQu+ZS3MZtztHKBrCmJ1/sKtrdBd/kytWu4O1Cu5E pvv8Pb4z2KalcC39DDGdEcWA+zXCOr0U/UGEU54EA0TRTi0NQ+TDBneFHvvW6ePyZu VKgEDmKceMC59oBbiA8Mo77aNqGIzzRpkWfU6i8s19fKnFkHPTO0A+2QMmAR3Xc+zx XQYLiGpknbGlIw1QgP86cThlLuZzvKgk9iw3f2ZQX0/UbB/SNWaxov6jQrb5RNffUF Tc9SMviVJBIb9iirn47uNABsTWOn9EPAu0N/B42m3HIzh6ltFSZwikB/siv2j1HZtx V0+e+46KPRikw== Received: from pat.atlnz.lc (Not Verified[10.32.16.33]) by svr-chch-seg1.atlnz.lc with Trustwave SEG (v8, 2, 6, 11305) id ; Thu, 06 May 2021 13:10:20 +1200 Received: from chrisp-dl.ws.atlnz.lc (chrisp-dl.ws.atlnz.lc [10.33.22.20]) by pat.atlnz.lc (Postfix) with ESMTP id 93FD113ECA6; Thu, 6 May 2021 13:10:20 +1200 (NZST) Received: by chrisp-dl.ws.atlnz.lc (Postfix, from userid 1030) id 8F14A283A60; Thu, 6 May 2021 13:10:20 +1200 (NZST) From: Chris Packham To: wsa@kernel.org, andriy.shevchenko@linux.intel.com, andy.shevchenko@gmail.com, robh+dt@kernel.org, mpe@ellerman.id.au Cc: linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Chris Packham Subject: [PATCH 0/3] P2040/P2041 i2c recovery erratum Date: Thu, 6 May 2021 13:10:11 +1200 Message-Id: <20210506011015.17347-1-chris.packham@alliedtelesis.co.nz> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-SEG-SpamProfiler-Analysis: v=2.3 cv=B+jHL9lM c=1 sm=1 tr=0 a=KLBiSEs5mFS1a/PbTCJxuA==:117 a=5FLXtPjwQuUA:10 a=LMdnaIF9TloyW3KOcEsA:9 X-SEG-SpamProfiler-Score: 0 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org The P2040/P2041 has an erratum where the i2c recovery scheme documented in the reference manual (and currently implemented in the i2c-mpc.c driver) does not work. The errata document provides an alternative that does work. This series implements that alternative and uses a property in the devicetree to decide when the alternative mechanism is needed. Chris Packham (3): dt-bindings: i2c: mpc: Add fsl,i2c-erratum-a004447 flag powerpc/fsl: set fsl,i2c-erratum-a004447 flag for P2041 i2c controllers i2c: mpc: implement erratum A-004447 workaround .../devicetree/bindings/i2c/i2c-mpc.yaml | 7 ++ arch/powerpc/boot/dts/fsl/p2041si-post.dtsi | 16 ++++ drivers/i2c/busses/i2c-mpc.c | 88 ++++++++++++++++++- 3 files changed, 109 insertions(+), 2 deletions(-)