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=-6.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 7A5E6C677D4 for ; Mon, 8 Oct 2018 18:37:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 39FA721479 for ; Mon, 8 Oct 2018 18:37:28 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="PC+n8YyH" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 39FA721479 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org 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 S1728895AbeJIBu2 (ORCPT ); Mon, 8 Oct 2018 21:50:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:36538 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726529AbeJIBu1 (ORCPT ); Mon, 8 Oct 2018 21:50:27 -0400 Received: from localhost (ip-213-127-77-176.ip.prioritytelecom.net [213.127.77.176]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C97892064A; Mon, 8 Oct 2018 18:37:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1539023844; bh=LuFs0W5VCZfh4oJu9gJN2hUZ9WyaZfpre3bLrOGj0cg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PC+n8YyHLsaFrR1Ox8wBYnwWVksnlDk/kb24vxejSH2qu/O8GlTrmoe+omdGg4MC2 r/jMqBcQAhM6ISloWsckCaIsqOqM+fNW0xFngoNE55wrH9gGgf3q/0sfblE88VqJUX 6RGfpKeaId3k5B8Ug9DczN6Wbuv78cr5VtNE8GtY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Masahiro Yamada , Wolfram Sang , Sasha Levin Subject: [PATCH 4.4 081/113] i2c: uniphier: issue STOP only for last message or I2C_M_STOP Date: Mon, 8 Oct 2018 20:31:22 +0200 Message-Id: <20181008175535.598855228@linuxfoundation.org> X-Mailer: git-send-email 2.19.0 In-Reply-To: <20181008175530.864641368@linuxfoundation.org> References: <20181008175530.864641368@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Masahiro Yamada [ Upstream commit 38f5d8d8cbb2ffa2b54315118185332329ec891c ] 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 Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/i2c/busses/i2c-uniphier.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) --- a/drivers/i2c/busses/i2c-uniphier.c +++ b/drivers/i2c/busses/i2c-uniphier.c @@ -247,11 +247,8 @@ static int uniphier_i2c_master_xfer(stru 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)