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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 0A53BC2D0E4 for ; Tue, 17 Nov 2020 13:49:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9322D20853 for ; Tue, 17 Nov 2020 13:49:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Pxlga5h0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732935AbgKQNhT (ORCPT ); Tue, 17 Nov 2020 08:37:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:48358 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732932AbgKQNhT (ORCPT ); Tue, 17 Nov 2020 08:37:19 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 96C13207BC; Tue, 17 Nov 2020 13:37:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605620237; bh=jdFjeQLXwz1AUXH3/IhR2QxGsaJzL6/2z11GV+zJXeI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Pxlga5h0eXqrNVhqj7tiF38Jg3UOJFKMOtI+bu9FDMrxtWa+KFJ3DU3AWOo5eYzNW 7TJMTja1g6hXfJzbi45qFxquonxjhoB3rQZNT4wYy/wZTxHr5vI2s6rPAlpvc7Oxxr RKAHP8aSr7dN6VDU5G8NLycLiVQA0YhFA1nOFZdY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Michael Wu , Jarkko Nikula , Wolfram Sang , Sasha Levin Subject: [PATCH 5.9 124/255] i2c: designware: slave should do WRITE_REQUESTED before WRITE_RECEIVED Date: Tue, 17 Nov 2020 14:04:24 +0100 Message-Id: <20201117122144.978039906@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201117122138.925150709@linuxfoundation.org> References: <20201117122138.925150709@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Michael Wu [ Upstream commit 3b5f7f10ff6e6b66f553e12cc50d9bb751ce60ad ] Sometimes we would get the following flow when doing an i2cset: 0x1 STATUS SLAVE_ACTIVITY=0x1 : RAW_INTR_STAT=0x514 : INTR_STAT=0x4 I2C_SLAVE_WRITE_RECEIVED 0x1 STATUS SLAVE_ACTIVITY=0x0 : RAW_INTR_STAT=0x714 : INTR_STAT=0x204 I2C_SLAVE_WRITE_REQUESTED I2C_SLAVE_WRITE_RECEIVED Documentation/i2c/slave-interface.rst says that I2C_SLAVE_WRITE_REQUESTED, which is mandatory, should be sent while the data did not arrive yet. It means in a write-request I2C_SLAVE_WRITE_REQUESTED should be reported before any I2C_SLAVE_WRITE_RECEIVED. By the way, I2C_SLAVE_STOP didn't be reported in the above case because DW_IC_INTR_STAT was not 0x200. dev->status can be used to record the current state, especially Designware I2C controller has no interrupts to identify a write-request. This patch makes not only I2C_SLAVE_WRITE_REQUESTED been reported first when IC_INTR_RX_FULL is rising and dev->status isn't STATUS_WRITE_IN_PROGRESS but also I2C_SLAVE_STOP been reported when a STOP condition is received. Signed-off-by: Michael Wu Acked-by: Jarkko Nikula Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin --- drivers/i2c/busses/i2c-designware-slave.c | 45 +++++++++-------------- 1 file changed, 18 insertions(+), 27 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-slave.c b/drivers/i2c/busses/i2c-designware-slave.c index 13de01a0f75f0..0d15f4c1e9f7e 100644 --- a/drivers/i2c/busses/i2c-designware-slave.c +++ b/drivers/i2c/busses/i2c-designware-slave.c @@ -172,26 +172,25 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev) "%#x STATUS SLAVE_ACTIVITY=%#x : RAW_INTR_STAT=%#x : INTR_STAT=%#x\n", enabled, slave_activity, raw_stat, stat); - if ((stat & DW_IC_INTR_RX_FULL) && (stat & DW_IC_INTR_STOP_DET)) - i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_REQUESTED, &val); + if (stat & DW_IC_INTR_RX_FULL) { + if (dev->status != STATUS_WRITE_IN_PROGRESS) { + dev->status = STATUS_WRITE_IN_PROGRESS; + i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_REQUESTED, + &val); + } + + regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); + val = tmp; + if (!i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED, + &val)) + dev_vdbg(dev->dev, "Byte %X acked!", val); + } if (stat & DW_IC_INTR_RD_REQ) { if (slave_activity) { - if (stat & DW_IC_INTR_RX_FULL) { - regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); - val = tmp; - - if (!i2c_slave_event(dev->slave, - I2C_SLAVE_WRITE_RECEIVED, - &val)) { - dev_vdbg(dev->dev, "Byte %X acked!", - val); - } - regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp); - } else { - regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp); - regmap_read(dev->map, DW_IC_CLR_RX_UNDER, &tmp); - } + regmap_read(dev->map, DW_IC_CLR_RD_REQ, &tmp); + + dev->status = STATUS_READ_IN_PROGRESS; if (!i2c_slave_event(dev->slave, I2C_SLAVE_READ_REQUESTED, &val)) @@ -203,18 +202,10 @@ static int i2c_dw_irq_handler_slave(struct dw_i2c_dev *dev) if (!i2c_slave_event(dev->slave, I2C_SLAVE_READ_PROCESSED, &val)) regmap_read(dev->map, DW_IC_CLR_RX_DONE, &tmp); - - i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val); - return 1; } - if (stat & DW_IC_INTR_RX_FULL) { - regmap_read(dev->map, DW_IC_DATA_CMD, &tmp); - val = tmp; - if (!i2c_slave_event(dev->slave, I2C_SLAVE_WRITE_RECEIVED, - &val)) - dev_vdbg(dev->dev, "Byte %X acked!", val); - } else { + if (stat & DW_IC_INTR_STOP_DET) { + dev->status = STATUS_IDLE; i2c_slave_event(dev->slave, I2C_SLAVE_STOP, &val); } -- 2.27.0