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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 F13D4C5CFC0 for ; Mon, 18 Jun 2018 08:33:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AB4C420864 for ; Mon, 18 Jun 2018 08:33:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AB4C420864 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 S967513AbeFRIdf (ORCPT ); Mon, 18 Jun 2018 04:33:35 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:35532 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S967497AbeFRIdc (ORCPT ); Mon, 18 Jun 2018 04:33:32 -0400 Received: from localhost (LFbn-1-12247-202.w90-92.abo.wanadoo.fr [90.92.61.202]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 9C9ABC49; Mon, 18 Jun 2018 08:33:31 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Baolin Wang , Wolfram Sang , Sasha Levin Subject: [PATCH 4.14 077/189] i2c: sprd: Fix the i2c count issue Date: Mon, 18 Jun 2018 10:12:53 +0200 Message-Id: <20180618081212.365784477@linuxfoundation.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180618081209.254234434@linuxfoundation.org> References: <20180618081209.254234434@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Baolin Wang [ Upstream commit 2a010461207cc96bee5ab81748325dec1972976f ] We found the I2C controller count register is unreliable sometimes, that will cause I2C to lose data. Thus we can read the data count from 'i2c_dev->count' instead of the I2C controller count register. Signed-off-by: Baolin Wang Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/i2c/busses/i2c-sprd.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) --- a/drivers/i2c/busses/i2c-sprd.c +++ b/drivers/i2c/busses/i2c-sprd.c @@ -368,13 +368,12 @@ static irqreturn_t sprd_i2c_isr_thread(i struct sprd_i2c *i2c_dev = dev_id; struct i2c_msg *msg = i2c_dev->msg; bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK); - u32 i2c_count = readl(i2c_dev->base + I2C_COUNT); u32 i2c_tran; if (msg->flags & I2C_M_RD) i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD; else - i2c_tran = i2c_count; + i2c_tran = i2c_dev->count; /* * If we got one ACK from slave when writing data, and we did not @@ -412,14 +411,13 @@ static irqreturn_t sprd_i2c_isr(int irq, { struct sprd_i2c *i2c_dev = dev_id; struct i2c_msg *msg = i2c_dev->msg; - u32 i2c_count = readl(i2c_dev->base + I2C_COUNT); bool ack = !(readl(i2c_dev->base + I2C_STATUS) & I2C_RX_ACK); u32 i2c_tran; if (msg->flags & I2C_M_RD) i2c_tran = i2c_dev->count >= I2C_FIFO_FULL_THLD; else - i2c_tran = i2c_count; + i2c_tran = i2c_dev->count; /* * If we did not get one ACK from slave when writing data, then we