iio: adc: ti-ads1119: Fix unbalanced pm reference count in ds1119_single_conversion()

[PATCH] iio: adc: ti-ads1119: Fix unbalanced pm reference count in ds1119_single_conversion()

Posted by Felix Gu 1 month, 2 weeks ago

In ads1119_single_conversion(), if pm_runtime_resume_and_get() fails,
the code jumps to the pdown label, which calls
pm_runtime_put_autosuspend().

Since pm_runtime_resume_and_get() automatically decrements the usage
counter on failure, the subsequent call to pm_runtime_put_autosuspend()
causes an unbalanced reference counter.

Fixes: a9306887eba4 ("iio: adc: ti-ads1119: Add driver")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
---
 drivers/iio/adc/ti-ads1119.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/iio/adc/ti-ads1119.c b/drivers/iio/adc/ti-ads1119.c
index c9cedc59cdcd..4454f28b2b58 100644
--- a/drivers/iio/adc/ti-ads1119.c
+++ b/drivers/iio/adc/ti-ads1119.c
@@ -274,7 +274,7 @@ static int ads1119_single_conversion(struct ads1119_state *st,
 
 	ret = pm_runtime_resume_and_get(dev);
 	if (ret)
-		goto pdown;
+		return ret;
 
 	ret = ads1119_configure_channel(st, mux, gain, datarate);
 	if (ret)

---
base-commit: 7d6661873f6b54c75195780a40d66bad3d482d8f
change-id: 20260228-ads1119-66b5271ef827

Best regards,
-- 
Felix Gu <ustc.gu@gmail.com>

Re: [PATCH] iio: adc: ti-ads1119: Fix unbalanced pm reference count in ds1119_single_conversion()

Posted by João Paulo Gonçalves 1 month, 2 weeks ago

Hello,

> Since pm_runtime_resume_and_get() automatically decrements the usage
> counter on failure, the subsequent call to pm_runtime_put_autosuspend()
> causes an unbalanced reference counter.

Reviewed-by: João Paulo Gonçalves <jpaulo.silvagoncalves@gmail.com>

Thanks for the fix!

The change looks correct to me, considering the auto-cleanup
implementation in pm_runtime. I need to take a proper look, but we
probably can get rid of the `pdown` label by using
PM_RUNTIME_ACQUIRE_IF_ENABLED_AUTOSUSPEND().

Att,
João Paulo

Re: [PATCH] iio: adc: ti-ads1119: Fix unbalanced pm reference count in ds1119_single_conversion()

Posted by Jonathan Cameron 1 month, 2 weeks ago

On Sat, 28 Feb 2026 01:48:19 +0800
Felix Gu <ustc.gu@gmail.com> wrote:

> In ads1119_single_conversion(), if pm_runtime_resume_and_get() fails,
> the code jumps to the pdown label, which calls
> pm_runtime_put_autosuspend().
> 
> Since pm_runtime_resume_and_get() automatically decrements the usage
> counter on failure, the subsequent call to pm_runtime_put_autosuspend()
> causes an unbalanced reference counter.
> 
> Fixes: a9306887eba4 ("iio: adc: ti-ads1119: Add driver")
> Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Hi Felix,

Looks correct to me.  Applied to the fixes-togreg branch of iio.git and
pushed out as testing.

More eyes always welcome though if others have time to take a look.

Jonathan

> ---
>  drivers/iio/adc/ti-ads1119.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/adc/ti-ads1119.c b/drivers/iio/adc/ti-ads1119.c
> index c9cedc59cdcd..4454f28b2b58 100644
> --- a/drivers/iio/adc/ti-ads1119.c
> +++ b/drivers/iio/adc/ti-ads1119.c
> @@ -274,7 +274,7 @@ static int ads1119_single_conversion(struct ads1119_state *st,
>  
>  	ret = pm_runtime_resume_and_get(dev);
>  	if (ret)
> -		goto pdown;
> +		return ret;
>  
>  	ret = ads1119_configure_channel(st, mux, gain, datarate);
>  	if (ret)
> 
> ---
> base-commit: 7d6661873f6b54c75195780a40d66bad3d482d8f
> change-id: 20260228-ads1119-66b5271ef827
> 
> Best regards,