iio: pressure: mpl115: Fix runtime PM leak in mpl115_read_raw()

[PATCH] iio: pressure: mpl115: Fix runtime PM leak in mpl115_read_raw()

Posted by Wentao Liang 1 week, 1 day ago

pm_runtime_get_sync() increments the usage counter even on failure,
so every successful call must be paired with a put. Both sensor read
failures returned early and skipped the paired
pm_runtime_put_autosuspend(), permanently preventing runtime suspend.

Fixes: 0c3a333524a3 ("iio: pressure: mpl115: Implementing low power mode by shutdown gpio")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
---
 drivers/iio/pressure/mpl115.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/pressure/mpl115.c b/drivers/iio/pressure/mpl115.c
index 830a5065c008..3266b79bdab8 100644
--- a/drivers/iio/pressure/mpl115.c
+++ b/drivers/iio/pressure/mpl115.c
@@ -106,8 +106,10 @@ static int mpl115_read_raw(struct iio_dev *indio_dev,
 	case IIO_CHAN_INFO_PROCESSED:
 		pm_runtime_get_sync(data->dev);
 		ret = mpl115_comp_pressure(data, val, val2);
-		if (ret < 0)
+		if (ret < 0) {
+			pm_runtime_put_autosuspend(data->dev);
 			return ret;
+		}
 		pm_runtime_put_autosuspend(data->dev);
 
 		return IIO_VAL_INT_PLUS_MICRO;
@@ -115,8 +117,10 @@ static int mpl115_read_raw(struct iio_dev *indio_dev,
 		pm_runtime_get_sync(data->dev);
 		/* temperature -5.35 C / LSB, 472 LSB is 25 C */
 		ret = mpl115_read_temp(data);
-		if (ret < 0)
+		if (ret < 0) {
+			pm_runtime_put_autosuspend(data->dev);
 			return ret;
+		}
 		pm_runtime_put_autosuspend(data->dev);
 		*val = ret >> 6;
 
-- 
2.34.1

Re: [PATCH] iio: pressure: mpl115: Fix runtime PM leak in mpl115_read_raw()

Posted by Jonathan Cameron 1 week, 1 day ago

On Wed, 16 Sep 2026 16:38:52 +0000
Wentao Liang <vulab@iscas.ac.cn> wrote:

> pm_runtime_get_sync() increments the usage counter even on failure,
> so every successful call must be paired with a put. Both sensor read
> failures returned early and skipped the paired
> pm_runtime_put_autosuspend(), permanently preventing runtime suspend.
> 
> Fixes: 0c3a333524a3 ("iio: pressure: mpl115: Implementing low power mode by shutdown gpio")
> Cc: stable@vger.kernel.org
> Signed-off-by: Wentao Liang <vulab@iscas.ac.cn>
see upstream...

> ---
>  drivers/iio/pressure/mpl115.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/iio/pressure/mpl115.c b/drivers/iio/pressure/mpl115.c
> index 830a5065c008..3266b79bdab8 100644
> --- a/drivers/iio/pressure/mpl115.c
> +++ b/drivers/iio/pressure/mpl115.c
> @@ -106,8 +106,10 @@ static int mpl115_read_raw(struct iio_dev *indio_dev,
>  	case IIO_CHAN_INFO_PROCESSED:
>  		pm_runtime_get_sync(data->dev);
>  		ret = mpl115_comp_pressure(data, val, val2);
> -		if (ret < 0)
> +		if (ret < 0) {
> +			pm_runtime_put_autosuspend(data->dev);
>  			return ret;
> +		}
>  		pm_runtime_put_autosuspend(data->dev);
>  
>  		return IIO_VAL_INT_PLUS_MICRO;
> @@ -115,8 +117,10 @@ static int mpl115_read_raw(struct iio_dev *indio_dev,
>  		pm_runtime_get_sync(data->dev);
>  		/* temperature -5.35 C / LSB, 472 LSB is 25 C */
>  		ret = mpl115_read_temp(data);
> -		if (ret < 0)
> +		if (ret < 0) {
> +			pm_runtime_put_autosuspend(data->dev);
>  			return ret;
> +		}
>  		pm_runtime_put_autosuspend(data->dev);
>  		*val = ret >> 6;
>