Re: [PATCH] iio: light: ltrf216a: fix runtime PM reference leak in error path

Joshua Crofts <[email protected]> Mon, 13 Jul 2026 14:28:09 +0200
Newsgroups dev.linux.lists.linux-kernel-mentees,org.kernel.vger.linux-iio,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
On Mon, 13 Jul 2026 07:58:29 +0530
Vidhu Sarwal <[email protected]> wrote:

> ltrf216a_get_lux() acquires a runtime PM reference by calling
> ltrf216a_set_power_state(data, true). However, if
> ltrf216a_read_data() fails, the function returns immediately without
> dropping the reference.
> 
> This leaves the runtime PM usage count unbalanced, preventing the device
> from autosuspending after a failed read.
> 
> Fix this by releasing the runtime PM reference before returning from the
> error path.
> 
> Fixes: 83f0bcd40d5c ("iio: light: Add support for ltrf216a sensor")
> Signed-off-by: Vidhu Sarwal <[email protected]>
> ---
>  drivers/iio/light/ltrf216a.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iio/light/ltrf216a.c b/drivers/iio/light/ltrf216a.c
> index 3f34ddc911b4..3ec239eb5831 100644
> --- a/drivers/iio/light/ltrf216a.c
> +++ b/drivers/iio/light/ltrf216a.c
> @@ -247,8 +247,10 @@ static int ltrf216a_get_lux(struct ltrf216a_data *data)
>  		return ret;
>  
>  	greendata = ltrf216a_read_data(data, LTRF216A_ALS_DATA_0);
> -	if (greendata < 0)
> +	if (greendata < 0) {
> +		ltrf216a_set_power_state(data, false);
>  		return greendata;
> +	}
>  
>  	ltrf216a_set_power_state(data, false);

LGTM, Sashiko had an issue with the fact that pm_runtime_mark_last_busy() isn't
called before autosuspending, however pm_runtime_put_autosuspend() already calls
this function in its body.

Reviewed-by: Joshua Crofts <[email protected]>

-- 
Kind regards

CJD