i2c: tegra: Fix PM device usage count

Message ID 20180224224423.hz36gpxnlpex2cqx@agrajag.zerfleddert.de
State New
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Series
  • i2c: tegra: Fix PM device usage count
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Commit Message

Tobias Jordan Feb. 24, 2018, 10:44 p.m.
pm_runtime_get_sync() increases the device's usage count even when
reporting an error, so add a call to pm_runtime_put_noidle() in the
related error branches.

Fixes: 1f50ad2c86cd ("i2c: tegra: Add runtime power-management support")
Signed-off-by: Tobias Jordan <Tobias.Jordan@elektrobit.com>
---
This is one of a number of patches for problems found using coccinelle 
scripting in the SIL2LinuxMP project. The patch has been compile-tested;
it's based on linux-next-20180223.

For a discussion of the corresponding issue, see
https://marc.info/?l=linux-pm&m=151904483924999&w=2

 drivers/i2c/busses/i2c-tegra.c | 2 ++
 1 file changed, 2 insertions(+)

Comments

Thierry Reding March 14, 2018, 12:10 p.m. | #1
On Sat, Feb 24, 2018 at 11:44:23PM +0100, Tobias Jordan wrote:
> pm_runtime_get_sync() increases the device's usage count even when
> reporting an error, so add a call to pm_runtime_put_noidle() in the
> related error branches.
> 
> Fixes: 1f50ad2c86cd ("i2c: tegra: Add runtime power-management support")
> Signed-off-by: Tobias Jordan <Tobias.Jordan@elektrobit.com>
> ---
> This is one of a number of patches for problems found using coccinelle 
> scripting in the SIL2LinuxMP project. The patch has been compile-tested;
> it's based on linux-next-20180223.
> 
> For a discussion of the corresponding issue, see
> https://marc.info/?l=linux-pm&m=151904483924999&w=2
> 
>  drivers/i2c/busses/i2c-tegra.c | 2 ++
>  1 file changed, 2 insertions(+)

This seems okay to me, though given the discussion it might be
preferable to just ignore errors rather than fail.

Acked-by: Thierry Reding <treding@nvidia.com>

Patch

diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index 60292d243e24..d53136538339 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -484,6 +484,7 @@  static int tegra_i2c_init(struct tegra_i2c_dev *i2c_dev)
 	err = pm_runtime_get_sync(i2c_dev->dev);
 	if (err < 0) {
 		dev_err(i2c_dev->dev, "runtime resume failed %d\n", err);
+		pm_runtime_put_noidle(i2c_dev->dev);
 		return err;
 	}
 
@@ -740,6 +741,7 @@  static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[],
 	ret = pm_runtime_get_sync(i2c_dev->dev);
 	if (ret < 0) {
 		dev_err(i2c_dev->dev, "runtime resume failed %d\n", ret);
+		pm_runtime_put_noidle(i2c_dev->dev);
 		return ret;
 	}