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=-2.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,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 E9676C433F4 for ; Fri, 31 Aug 2018 14:31:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9B5BA20661 for ; Fri, 31 Aug 2018 14:31:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=nifty.com header.i=@nifty.com header.b="l44D8bHU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9B5BA20661 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=socionext.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728634AbeHaSjU (ORCPT ); Fri, 31 Aug 2018 14:39:20 -0400 Received: from conuserg-08.nifty.com ([210.131.2.75]:52189 "EHLO conuserg-08.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727591AbeHaSjU (ORCPT ); Fri, 31 Aug 2018 14:39:20 -0400 Received: from grover.tkatk1.zaq.ne.jp (zaqdadce369.zaq.ne.jp [218.220.227.105]) (authenticated) by conuserg-08.nifty.com with ESMTP id w7VEUp9g030172; Fri, 31 Aug 2018 23:30:51 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-08.nifty.com w7VEUp9g030172 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1535725852; bh=Ky6qwotd80ihjx5nlKTuOrYtigeiIdPoY6NspfMkiMg=; h=From:To:Cc:Subject:Date:From; b=l44D8bHUOIcL6W8aVWZQiXGcoD8p6PeFhyPxmPELgON7PCWlSd7icR2iMmUruedrn eyglEoUj929aFXvTh4lyv7CZZV+F+sONsb2m6+SHwlNCeyQny0XJB82SHcYKf21EcK vog4DONJx9MTd1AV1QdprRCw7qVxClT1qOigT6fLjRjWbvGOPav8flYg0950r3b9NI /jLOe/onRTFftWB1GWS4K4VLjCmpi8nc/XRBkkPbU5hbwcTAlsuooISnclbq0sAXe6 hiqsg9v0N35/IIUaOOlF9smql4bnqyAYQkaGSBV2jf3c1ZDAUOTqtpjfQBoPIrwdpw PVPWDG2E5XwDQ== X-Nifty-SrcIP: [218.220.227.105] From: Masahiro Yamada To: linux-i2c@vger.kernel.org Cc: Wolfram Sang , Masahiro Yamada , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/2] i2c: uniphier: issue STOP only for last message or I2C_M_STOP Date: Fri, 31 Aug 2018 23:30:47 +0900 Message-Id: <1535725848-4076-1-git-send-email-yamada.masahiro@socionext.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This driver currently emits a STOP if the next message is not I2C_MD_RD. It should not do it because it disturbs the I2C_RDWR ioctl, where read/write transactions are combined without STOP between. Issue STOP only when the message is the last one _or_ flagged with I2C_M_STOP. Fixes: dd6fd4a32793 ("i2c: uniphier: add UniPhier FIFO-less I2C driver") Signed-off-by: Masahiro Yamada --- drivers/i2c/busses/i2c-uniphier.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/drivers/i2c/busses/i2c-uniphier.c b/drivers/i2c/busses/i2c-uniphier.c index bb181b0..454f914 100644 --- a/drivers/i2c/busses/i2c-uniphier.c +++ b/drivers/i2c/busses/i2c-uniphier.c @@ -248,11 +248,8 @@ static int uniphier_i2c_master_xfer(struct i2c_adapter *adap, return ret; for (msg = msgs; msg < emsg; msg++) { - /* If next message is read, skip the stop condition */ - bool stop = !(msg + 1 < emsg && msg[1].flags & I2C_M_RD); - /* but, force it if I2C_M_STOP is set */ - if (msg->flags & I2C_M_STOP) - stop = true; + /* Emit STOP if it is the last message or I2C_M_STOP is set. */ + bool stop = (msg + 1 == emsg) || (msg->flags & I2C_M_STOP); ret = uniphier_i2c_master_xfer_one(adap, msg, stop); if (ret) -- 2.7.4