From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Tue, 17 Jul 2018 13:48:52 +0200 (CEST) Received: from mail.bootlin.com ([62.4.15.54]:44072 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by eddie.linux-mips.org with ESMTP id S23992482AbeGQLsquM1jT (ORCPT ); Tue, 17 Jul 2018 13:48:46 +0200 Received: by mail.bootlin.com (Postfix, from userid 110) id 3357120876; Tue, 17 Jul 2018 13:48:41 +0200 (CEST) Received: from localhost (242.171.71.37.rev.sfr.net [37.71.171.242]) by mail.bootlin.com (Postfix) with ESMTPSA id 08E2620765; Tue, 17 Jul 2018 13:48:41 +0200 (CEST) From: Alexandre Belloni To: Wolfram Sang , Jarkko Nikula , James Hogan Cc: Paul Burton , Andy Shevchenko , Mika Westerberg , linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@linux-mips.org, Thomas Petazzoni , Allan Nielsen , Alexandre Belloni Subject: [PATCH 1/5] i2c: designware: factorize setting SDA hold time Date: Tue, 17 Jul 2018 13:48:33 +0200 Message-Id: <20180717114837.21839-2-alexandre.belloni@bootlin.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20180717114837.21839-1-alexandre.belloni@bootlin.com> References: <20180717114837.21839-1-alexandre.belloni@bootlin.com> Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 64872 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: alexandre.belloni@bootlin.com Precedence: bulk List-help: List-unsubscribe: List-software: Ecartis version 1.0.0 List-Id: linux-mips X-List-ID: linux-mips List-subscribe: List-owner: List-post: List-archive: X-list: linux-mips Factorize setting the SDA hold time in a new function i2c_dw_set_sda_hold_time() that is used for both master and slave mode. This conveniently pulls the fix for the spurious warning from commit 7a20e707aae2 ("i2c: designware: suppress unneeded SDA hold time warnings") in slave mode. Signed-off-by: Alexandre Belloni --- drivers/i2c/busses/i2c-designware-common.c | 27 ++++++++++++++++++++++ drivers/i2c/busses/i2c-designware-core.h | 1 + drivers/i2c/busses/i2c-designware-master.c | 22 +----------------- drivers/i2c/busses/i2c-designware-slave.c | 22 +----------------- 4 files changed, 30 insertions(+), 42 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c index 48914dfc8ce8..9afc3e075b33 100644 --- a/drivers/i2c/busses/i2c-designware-common.c +++ b/drivers/i2c/busses/i2c-designware-common.c @@ -293,5 +293,32 @@ u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev) } EXPORT_SYMBOL_GPL(i2c_dw_read_comp_param); +void i2c_dw_set_sda_hold_time(struct dw_i2c_dev *dev) +{ + u32 reg; + + /* Configure SDA Hold Time if required. */ + reg = dw_readl(dev, DW_IC_COMP_VERSION); + if (reg >= DW_IC_SDA_HOLD_MIN_VERS) { + if (!dev->sda_hold_time) { + /* Keep previous hold time setting if no one set it. */ + dev->sda_hold_time = dw_readl(dev, DW_IC_SDA_HOLD); + } + /* + * Workaround for avoiding TX arbitration lost in case I2C + * slave pulls SDA down "too quickly" after falling egde of + * SCL by enabling non-zero SDA RX hold. Specification says it + * extends incoming SDA low to high transition while SCL is + * high but it apprears to help also above issue. + */ + if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK)) + dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT; + dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD); + } else if (dev->sda_hold_time) { + dev_warn(dev->dev, + "Hardware too old to adjust SDA hold time.\n"); + } +} + MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter core"); MODULE_LICENSE("GPL"); diff --git a/drivers/i2c/busses/i2c-designware-core.h b/drivers/i2c/busses/i2c-designware-core.h index d690e648bc01..bc43fb9ac1cf 100644 --- a/drivers/i2c/busses/i2c-designware-core.h +++ b/drivers/i2c/busses/i2c-designware-core.h @@ -306,6 +306,7 @@ int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev); u32 i2c_dw_func(struct i2c_adapter *adap); void i2c_dw_disable(struct dw_i2c_dev *dev); void i2c_dw_disable_int(struct dw_i2c_dev *dev); +void i2c_dw_set_sda_hold_time(struct dw_i2c_dev *dev); static inline void __i2c_dw_enable(struct dw_i2c_dev *dev) { diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c index 27436a937492..826329f8e30b 100644 --- a/drivers/i2c/busses/i2c-designware-master.c +++ b/drivers/i2c/busses/i2c-designware-master.c @@ -146,27 +146,7 @@ static int i2c_dw_init_master(struct dw_i2c_dev *dev) } } - /* Configure SDA Hold Time if required */ - reg = dw_readl(dev, DW_IC_COMP_VERSION); - if (reg >= DW_IC_SDA_HOLD_MIN_VERS) { - if (!dev->sda_hold_time) { - /* Keep previous hold time setting if no one set it */ - dev->sda_hold_time = dw_readl(dev, DW_IC_SDA_HOLD); - } - /* - * Workaround for avoiding TX arbitration lost in case I2C - * slave pulls SDA down "too quickly" after falling egde of - * SCL by enabling non-zero SDA RX hold. Specification says it - * extends incoming SDA low to high transition while SCL is - * high but it apprears to help also above issue. - */ - if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK)) - dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT; - dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD); - } else if (dev->sda_hold_time) { - dev_warn(dev->dev, - "Hardware too old to adjust SDA hold time.\n"); - } + i2c_dw_set_sda_hold_time(dev); i2c_dw_configure_fifo_master(dev); i2c_dw_release_lock(dev); diff --git a/drivers/i2c/busses/i2c-designware-slave.c b/drivers/i2c/busses/i2c-designware-slave.c index 8ce2cd368477..150e5edb064c 100644 --- a/drivers/i2c/busses/i2c-designware-slave.c +++ b/drivers/i2c/busses/i2c-designware-slave.c @@ -77,27 +77,7 @@ static int i2c_dw_init_slave(struct dw_i2c_dev *dev) /* Disable the adapter. */ __i2c_dw_disable(dev); - /* Configure SDA Hold Time if required. */ - reg = dw_readl(dev, DW_IC_COMP_VERSION); - if (reg >= DW_IC_SDA_HOLD_MIN_VERS) { - if (!dev->sda_hold_time) { - /* Keep previous hold time setting if no one set it. */ - dev->sda_hold_time = dw_readl(dev, DW_IC_SDA_HOLD); - } - /* - * Workaround for avoiding TX arbitration lost in case I2C - * slave pulls SDA down "too quickly" after falling egde of - * SCL by enabling non-zero SDA RX hold. Specification says it - * extends incoming SDA low to high transition while SCL is - * high but it apprears to help also above issue. - */ - if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK)) - dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT; - dw_writel(dev, dev->sda_hold_time, DW_IC_SDA_HOLD); - } else { - dev_warn(dev->dev, - "Hardware too old to adjust SDA hold time.\n"); - } + i2c_dw_set_sda_hold_time(dev); i2c_dw_configure_fifo_slave(dev); i2c_dw_release_lock(dev); -- 2.18.0