From mboxrd@z Thu Jan 1 00:00:00 1970 From: jszhang@marvell.com (Jisheng Zhang) Date: Fri, 22 Apr 2016 16:49:31 +0800 Subject: [PATCH v4] i2c: designware-platdrv: fix unbalanced clk enable and prepare Message-ID: <1461314971-5944-1-git-send-email-jszhang@marvell.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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: ?- s/clk/clock ?- describe why use pm_runtime_put_noidle() Since v1: ?- fix commit msg: "not rely on rpm" rather than "rely on rpm" ?- 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_device *pdev) } r = 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); + } return r; } @@ -264,15 +267,16 @@ static int dw_i2c_plat_remove(struct platform_device *pdev) struct dw_i2c_dev *dev = platform_get_drvdata(pdev); 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); i2c_del_adapter(&dev->adapter); i2c_dw_disable(dev); - 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); return 0; } -- 2.8.1