From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933606AbcIALqP (ORCPT ); Thu, 1 Sep 2016 07:46:15 -0400 Received: from conuserg-08.nifty.com ([210.131.2.75]:41141 "EHLO conuserg-08.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933352AbcIALpf (ORCPT ); Thu, 1 Sep 2016 07:45:35 -0400 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-08.nifty.com u81BiPw3020288 X-Nifty-SrcIP: [153.142.97.92] From: Masahiro Yamada To: linux-i2c@vger.kernel.org Cc: Masahiro Yamada , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Wolfram Sang Subject: [PATCH 3/3] i2c: uniphier-f: set the adapter to master mode when probing Date: Thu, 1 Sep 2016 20:46:30 +0900 Message-Id: <1472730390-8907-4-git-send-email-yamada.masahiro@socionext.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1472730390-8907-1-git-send-email-yamada.masahiro@socionext.com> References: <1472730390-8907-1-git-send-email-yamada.masahiro@socionext.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently, the adapter is set to the master mode at the first use. Since then, it is kept in the slave mode, so unexpected glitch signals on the I2C lines may cause the adapter into insane state. Setting it to the master mode along with initialization solves the problem. Signed-off-by: Masahiro Yamada Reported-by: Akio Noda --- drivers/i2c/busses/i2c-uniphier-f.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/busses/i2c-uniphier-f.c b/drivers/i2c/busses/i2c-uniphier-f.c index 2886685..829df91 100644 --- a/drivers/i2c/busses/i2c-uniphier-f.c +++ b/drivers/i2c/busses/i2c-uniphier-f.c @@ -458,16 +458,20 @@ static struct i2c_bus_recovery_info uniphier_fi2c_bus_recovery_info = { static void uniphier_fi2c_hw_init(struct uniphier_fi2c_priv *priv, u32 bus_speed, unsigned long clk_rate) { - u32 clk_count; + u32 tmp; + + tmp = readl(priv->membase + UNIPHIER_FI2C_CR); + tmp |= UNIPHIER_FI2C_CR_MST; + writel(tmp, priv->membase + UNIPHIER_FI2C_CR); uniphier_fi2c_reset(priv); - clk_count = clk_rate / bus_speed; + tmp = clk_rate / bus_speed; - writel(clk_count, priv->membase + UNIPHIER_FI2C_CYC); - writel(clk_count / 2, priv->membase + UNIPHIER_FI2C_LCTL); - writel(clk_count / 2, priv->membase + UNIPHIER_FI2C_SSUT); - writel(clk_count / 16, priv->membase + UNIPHIER_FI2C_DSUT); + writel(tmp, priv->membase + UNIPHIER_FI2C_CYC); + writel(tmp / 2, priv->membase + UNIPHIER_FI2C_LCTL); + writel(tmp / 2, priv->membase + UNIPHIER_FI2C_SSUT); + writel(tmp / 16, priv->membase + UNIPHIER_FI2C_DSUT); uniphier_fi2c_prepare_operation(priv); } -- 1.9.1