From patchwork Thu Sep 1 11:46:28 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Masahiro Yamada X-Patchwork-Id: 75200 Delivered-To: patch@linaro.org Received: by 10.140.29.8 with SMTP id a8csp249252qga; Thu, 1 Sep 2016 04:45:49 -0700 (PDT) X-Received: by 10.98.89.23 with SMTP id n23mr25957333pfb.34.1472730347547; Thu, 01 Sep 2016 04:45:47 -0700 (PDT) Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id zj4si5309494pac.95.2016.09.01.04.45.47; Thu, 01 Sep 2016 04:45:47 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@nifty.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933576AbcIALpn (ORCPT + 27 others); Thu, 1 Sep 2016 07:45:43 -0400 Received: from conuserg-08.nifty.com ([210.131.2.75]:41140 "EHLO conuserg-08.nifty.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933357AbcIALpf (ORCPT ); Thu, 1 Sep 2016 07:45:35 -0400 Received: from beagle.diag.org (p14092-ipngnfx01kyoto.kyoto.ocn.ne.jp [153.142.97.92]) (authenticated) by conuserg-08.nifty.com with ESMTP id u81BiPw1020288; Thu, 1 Sep 2016 20:44:26 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conuserg-08.nifty.com u81BiPw1020288 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1472730266; bh=bix3bPcT7Bj3haTX8JKzqB4b8c6kgjTrgf3l/mdpd6s=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=voh18gyoLj41zaAwZRAeCSzuY8bslUR4A9Ic/2aHyEfw1qaieAq3c4cHKKZRL0hLP 18mqSIcc/nT07zQko0JBmTXgMgjocfcWrAUdboGwLXrK9k3hZPGnFEs8n/IPQ6nxnq TQiSPLtvCOTZHUPFX2d9Hte0YOcJDk8MpzLQFs6sP7wD4MVB3rw2Y6atgS5J/x4LSJ MAx/5UHKWkLbsAn9IpB4WQsb2nk+E/a+HjkwAAiC4zko6t7una71h87iVj8v6sVLkB d4SYtL76RTrffh9FZbxGAEiczED8pQDtldZzrr6LeF2lbeiH6noYzTmRVjYlDWzL8V GBg8VEbgjsHJg== 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 1/3] i2c: uniphier: avoid WARN_ON() of clk_disable() in failure path Date: Thu, 1 Sep 2016 20:46:28 +0900 Message-Id: <1472730390-8907-2-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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If clk_prepare_enable() fails, clk_disable_unprepare() is called in the failure path, where the enable_count is still zero, so it hits WARN_ON(core->enable_count == 0) in the clk_core_disable(). To fix this, make the clock setting more linear in the probe function so that it can exploit "goto err" in case of error. Signed-off-by: Masahiro Yamada --- drivers/i2c/busses/i2c-uniphier.c | 73 +++++++++++++++++---------------------- 1 file changed, 31 insertions(+), 42 deletions(-) -- 1.9.1 diff --git a/drivers/i2c/busses/i2c-uniphier.c b/drivers/i2c/busses/i2c-uniphier.c index d6e612a..56e92af 100644 --- a/drivers/i2c/busses/i2c-uniphier.c +++ b/drivers/i2c/busses/i2c-uniphier.c @@ -316,50 +316,15 @@ static struct i2c_bus_recovery_info uniphier_i2c_bus_recovery_info = { .unprepare_recovery = uniphier_i2c_unprepare_recovery, }; -static int uniphier_i2c_clk_init(struct device *dev, - struct uniphier_i2c_priv *priv) +static void uniphier_i2c_hw_init(struct uniphier_i2c_priv *priv, + u32 bus_speed, unsigned long clk_rate) { - struct device_node *np = dev->of_node; - unsigned long clk_rate; - u32 bus_speed; - int ret; - - if (of_property_read_u32(np, "clock-frequency", &bus_speed)) - bus_speed = UNIPHIER_I2C_DEFAULT_SPEED; - - if (!bus_speed) { - dev_err(dev, "clock-frequency should not be zero\n"); - return -EINVAL; - } - - if (bus_speed > UNIPHIER_I2C_MAX_SPEED) - bus_speed = UNIPHIER_I2C_MAX_SPEED; - - /* Get input clk rate through clk driver */ - priv->clk = devm_clk_get(dev, NULL); - if (IS_ERR(priv->clk)) { - dev_err(dev, "failed to get clock\n"); - return PTR_ERR(priv->clk); - } - - ret = clk_prepare_enable(priv->clk); - if (ret) - return ret; - - clk_rate = clk_get_rate(priv->clk); - if (!clk_rate) { - dev_err(dev, "input clock rate should not be zero\n"); - return -EINVAL; - } - uniphier_i2c_reset(priv, true); writel((clk_rate / bus_speed / 2 << 16) | (clk_rate / bus_speed), priv->membase + UNIPHIER_I2C_CLK); uniphier_i2c_reset(priv, false); - - return 0; } static int uniphier_i2c_probe(struct platform_device *pdev) @@ -367,8 +332,9 @@ static int uniphier_i2c_probe(struct platform_device *pdev) struct device *dev = &pdev->dev; struct uniphier_i2c_priv *priv; struct resource *regs; - int irq; - int ret; + u32 bus_speed; + unsigned long clk_rate; + int irq, ret; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) @@ -385,6 +351,31 @@ static int uniphier_i2c_probe(struct platform_device *pdev) return irq; } + if (of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed)) + bus_speed = UNIPHIER_I2C_DEFAULT_SPEED; + + if (!bus_speed || bus_speed > UNIPHIER_I2C_MAX_SPEED) { + dev_err(dev, "invalid clock-frequency %d\n", bus_speed); + return -EINVAL; + } + + priv->clk = devm_clk_get(dev, NULL); + if (IS_ERR(priv->clk)) { + dev_err(dev, "failed to get clock\n"); + return PTR_ERR(priv->clk); + } + + ret = clk_prepare_enable(priv->clk); + if (ret) + return ret; + + clk_rate = clk_get_rate(priv->clk); + if (!clk_rate) { + dev_err(dev, "input clock rate should not be zero\n"); + ret = -EINVAL; + goto err; + } + init_completion(&priv->comp); priv->adap.owner = THIS_MODULE; priv->adap.algo = &uniphier_i2c_algo; @@ -395,9 +386,7 @@ static int uniphier_i2c_probe(struct platform_device *pdev) i2c_set_adapdata(&priv->adap, priv); platform_set_drvdata(pdev, priv); - ret = uniphier_i2c_clk_init(dev, priv); - if (ret) - goto err; + uniphier_i2c_hw_init(priv, bus_speed, clk_rate); ret = devm_request_irq(dev, irq, uniphier_i2c_interrupt, 0, pdev->name, priv);