From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jisheng Zhang Subject: [PATCH v4] i2c: designware-platdrv: fix unbalanced clk enable and prepare Date: Fri, 22 Apr 2016 16:49:31 +0800 Message-ID: <1461314971-5944-1-git-send-email-jszhang@marvell.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from mx0b-0016f401.pphosted.com ([67.231.156.173]:59322 "EHLO mx0b-0016f401.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751659AbcDVIxj (ORCPT ); Fri, 22 Apr 2016 04:53:39 -0400 Sender: linux-i2c-owner@vger.kernel.org List-Id: linux-i2c@vger.kernel.org To: jarkko.nikula@linux.intel.com, andriy.shevchenko@linux.intel.com, mika.westerberg@linux.intel.com, wsa@the-dreams.de Cc: linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Jisheng Zhang If i2c_dw_probe() fails, we should disable and unprepare the clock, otherwise the clock enable and prepare is left unbalanced. In dw_i2c_plat_remove(), we'd better to not rely on runtime PM to disable and unprepare the clock since CONFIG_PM may be disabled when configuring the kernel. So we explicitly disable and unprepare the clock in dw_i2c_plat_remove() rather than implicitly rely on pm_runtime_put_sync(). To keep the device usage count balanced, we call pm_runtime_put_noidle() to decrease the usage count. Signed-off-by: Jisheng Zhang --- Since v3: - use runtime PM rather than rpm in commit msg - remove duplicated "(" in commit msg Since v2: =C2=A0- s/clk/clock =C2=A0- describe why use pm_runtime_put_noidle() =20 Since v1: =C2=A0- fix commit msg: "not rely on rpm" rather than "rely on rpm" =C2=A0- call i2c_dw_plat_prepare_clk after pm_rumtime_disable() drivers/i2c/busses/i2c-designware-platdrv.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/= busses/i2c-designware-platdrv.c index d656657..a771781 100644 --- a/drivers/i2c/busses/i2c-designware-platdrv.c +++ b/drivers/i2c/busses/i2c-designware-platdrv.c @@ -253,8 +253,11 @@ static int dw_i2c_plat_probe(struct platform_devic= e *pdev) } =20 r =3D i2c_dw_probe(dev); - if (r && !dev->pm_runtime_disabled) - pm_runtime_disable(&pdev->dev); + if (r) { + if (!dev->pm_runtime_disabled) + pm_runtime_disable(&pdev->dev); + i2c_dw_plat_prepare_clk(dev, false); + } =20 return r; } @@ -264,15 +267,16 @@ static int dw_i2c_plat_remove(struct platform_dev= ice *pdev) struct dw_i2c_dev *dev =3D platform_get_drvdata(pdev); =20 pm_runtime_get_sync(&pdev->dev); + pm_runtime_dont_use_autosuspend(&pdev->dev); + if (!dev->pm_runtime_disabled) + pm_runtime_disable(&pdev->dev); + pm_runtime_put_noidle(&pdev->dev); =20 i2c_del_adapter(&dev->adapter); =20 i2c_dw_disable(dev); =20 - pm_runtime_dont_use_autosuspend(&pdev->dev); - pm_runtime_put_sync(&pdev->dev); - if (!dev->pm_runtime_disabled) - pm_runtime_disable(&pdev->dev); + i2c_dw_plat_prepare_clk(dev, false); =20 return 0; } --=20 2.8.1