Re: [PATCH] iio: light: apds9306: fix PM reference leak in apds9306_read_data()

[Jonathan Cameron]

On Sat, 25 Jul 2026 05:10:48 +0000
Moksh Panicker <mokshpanicker.7@xxxxxxxxx> wrote:

> apds9306_read_data() calls pm_runtime_resume_and_get() but several
> error paths return directly without calling pm_runtime_put_autosuspend(),
> leaking the runtime PM reference and preventing the device from
> autosuspending.
> 
> Add a goto label before pm_runtime_put_autosuspend() and use it on
> all error paths after a successful pm_runtime_resume_and_get().
> 
> Fixes: 620d1e6c7a3f ("iio: light: Add support for APDS9306 Light Sensor")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Moksh Panicker <mokshpanicker.7@xxxxxxxxx>
Good find.
Please look at PM_RUNTIME_ACQUIRE_AUTOSUSPEND() and matching ERR macro.

Using that should simplify this fix quite a bit and generally give us nicer code.


> ---
>  drivers/iio/light/apds9306.c | 19 +++++++++++--------
>  1 file changed, 11 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/iio/light/apds9306.c b/drivers/iio/light/apds9306.c
> index 5ca4c87524fe..014db7a1787e 100644
> --- a/drivers/iio/light/apds9306.c
> +++ b/drivers/iio/light/apds9306.c
> @@ -475,19 +475,21 @@ static int apds9306_read_data(struct apds9306_data *data, int *val, int reg)
>  
>  	ret = regmap_field_read(rf->intg_time, &intg_time_idx);
>  	if (ret)
> -		return ret;
> +		goto out_pm_put;
>  
>  	ret = regmap_field_read(rf->repeat_rate, &repeat_rate_idx);
>  	if (ret)
> -		return ret;
> +		goto out_pm_put;
>  
>  	ret = regmap_field_read(rf->int_src, &int_src);
>  	if (ret)
> -		return ret;
> +		goto out_pm_put;
>  
>  	intg_time = iio_gts_find_int_time_by_sel(&data->gts, intg_time_idx);
> -	if (intg_time < 0)
> -		return intg_time;
> +	if (intg_time < 0) {
> +		ret = intg_time;
> +		goto out_pm_put;
> +	}
>  
>  	/* Whichever is greater - integration time period or sampling period. */
>  	delay = max(intg_time, apds9306_repeat_rate_period[repeat_rate_idx]);
> @@ -510,7 +512,7 @@ static int apds9306_read_data(struct apds9306_data *data, int *val, int reg)
>  						  APDS9306_ALS_INT_STAT_MASK)),
>  				       APDS9306_ALS_READ_DATA_DELAY_US, delay * 2);
>  	if (ret)
> -		return ret;
> +		goto out_pm_put;
>  
>  	/* If we reach here before the interrupt handler we push an event */
>  	if ((status & APDS9306_ALS_INT_STAT_MASK)) {
> @@ -530,14 +532,15 @@ static int apds9306_read_data(struct apds9306_data *data, int *val, int reg)
>  	ret = regmap_bulk_read(data->regmap, reg, buff, sizeof(buff));
>  	if (ret) {
>  		dev_err_ratelimited(dev, "read data failed\n");
> -		return ret;
> +		goto out_pm_put;
>  	}
>  
>  	*val = get_unaligned_le24(&buff);
>  
> +out_pm_put:
>  	pm_runtime_put_autosuspend(data->dev);
>  
> -	return 0;
> +	return ret;
>  }
>  
>  static int apds9306_intg_time_get(struct apds9306_data *data, int *val2)