2016-04-21 09:31:13

by Jisheng Zhang

Subject: [PATCH v2] i2c: designware-platdrv: fix unbalanced clk enable and prepare

If i2c_dw_probe() fail, we should disable and unprepare the clk,
otherwise the clk enable and prepare is left unbalanced.

In dw_i2c_plat_remove(), we'd better to not rely on rpm to disable
and unprepare the clk since CONFIG_PM may be disabled when configuring
the kernel. So we explicitly disable and unprepare the clk in
dw_i2c_plat_remove().

Signed-off-by: Jisheng Zhang <[email protected]>
---
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

2016-04-21 11:02:35

by Andy Shevchenko

Subject: Re: [PATCH v2] i2c: designware-platdrv: fix unbalanced clk enable and prepare

On Thu, 2016-04-21 at 17:26 +0800, Jisheng Zhang wrote:
> If i2c_dw_probe() fail, we should disable and unprepare the clk,

clk -> clock, or use function name explicitly.

> otherwise the clk enable and prepare is left unbalanced.
>

Ditto.

> In dw_i2c_plat_remove(), we'd better to not rely on rpm to disable
> and unprepare the clk since CONFIG_PM may be disabled when configuring

Ditto.

> the kernel. So we explicitly disable and unprepare the clk in

Ditto.

> dw_i2c_plat_remove().


> + pm_runtime_put_noidle(&pdev->dev);
>  
> - pm_runtime_put_sync(&pdev->dev);
>

This change also needs to be described in the commit message.

--
Andy Shevchenko <[email protected]>
Intel Finland Oy