Re: [PATCH v2 14/17] iio: light: pa12203001: Discard pm_runtime_put_autosuspend() return values

From: Jonathan Cameron

Date: Sun Oct 25 2026 - 21:08:59 EST


On Wed, 21 Oct 2026 16:57:15 -0700
Brian Norris <briannorris@xxxxxxxxxxxx> wrote:

> This driver propagates the return value of pm_runtime_put_autosuspend(),
> which is not particularly useful.
>
> Returning an error code from pm_runtime_put_autosuspend() merely means
> that it has not queued up a timer or work item to check whether or not
> the device can be suspended and there are many perfectly valid
> situations in which that can happen, like after writing "on" to the
> device's runtime PM "control" attribute in sysfs for one example.
>
> For this reason, modify this driver to simply discard the
> pm_runtime_put_autosuspend() return value, and inline some of the
> runtime PM helper function, now that it behaves the same with and
> without CONFIG_PM.
>
> This will facilitate a planned change of the
> pm_runtime_put_autosuspend() return type to void in the future, similar
> to commit 3afd8df02433 ("PM: runtime: Change pm_runtime_put() return
> type to void").
>
> Signed-off-by: Brian Norris <briannorris@xxxxxxxxxxxx>
Applied. Note I sent a follow up just now to use guard() on
the code that is visible in context here.

Thanks,

Jonathan

> ---
>
> Changes in v2:
> * Split iio patch into per-driver patches
> * Inlining
>
> drivers/iio/light/pa12203001.c | 26 +++++++++-----------------
> 1 file changed, 9 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/iio/light/pa12203001.c b/drivers/iio/light/pa12203001.c
> index c0f4db8d95f7..0a0502a60a06 100644
> --- a/drivers/iio/light/pa12203001.c
> +++ b/drivers/iio/light/pa12203001.c
> @@ -154,13 +154,12 @@ static inline int pa12203001_px_enable(struct pa12203001_data *data, u8 enable)
> return 0;
> }
>
> -static int pa12203001_set_power_state(struct pa12203001_data *data, bool on,
> - u8 mask)
> +static int pa12203001_runtime_resume_and_get(struct pa12203001_data *data, u8 mask)
> {
> #ifdef CONFIG_PM
> int ret;
>
> - if (on && (mask & PA12203001_ALS_EN_MASK)) {
> + if (mask & PA12203001_ALS_EN_MASK) {
> mutex_lock(&data->lock);
> if (data->px_enabled) {
> ret = pa12203001_als_enable(data,
> @@ -173,7 +172,7 @@ static int pa12203001_set_power_state(struct pa12203001_data *data, bool on,
> mutex_unlock(&data->lock);
> }
>
> - if (on && (mask & PA12203001_PX_EN_MASK)) {
> + if (mask & PA12203001_PX_EN_MASK) {
> mutex_lock(&data->lock);
> if (data->als_enabled) {
> ret = pa12203001_px_enable(data, PA12203001_PX_EN_MASK);
> @@ -185,10 +184,7 @@ static int pa12203001_set_power_state(struct pa12203001_data *data, bool on,
> mutex_unlock(&data->lock);
> }
>
> - if (on)
> - return pm_runtime_resume_and_get(&data->client->dev);
> -
> - return pm_runtime_put_autosuspend(&data->client->dev);
> + return pm_runtime_resume_and_get(&data->client->dev);
>
> err:
> mutex_unlock(&data->lock);
> @@ -213,7 +209,7 @@ static int pa12203001_read_raw(struct iio_dev *indio_dev,
> switch (chan->type) {
> case IIO_LIGHT:
> dev_mask = PA12203001_ALS_EN_MASK;
> - ret = pa12203001_set_power_state(data, true, dev_mask);
> + ret = pa12203001_runtime_resume_and_get(data, dev_mask);
> if (ret < 0)
> return ret;
> /*
> @@ -226,13 +222,11 @@ static int pa12203001_read_raw(struct iio_dev *indio_dev,
> goto reg_err;
>
> *val = le16_to_cpu(reg_word);
> - ret = pa12203001_set_power_state(data, false, dev_mask);
> - if (ret < 0)
> - return ret;
> + pm_runtime_put_autosuspend(&data->client->dev);
> break;
> case IIO_PROXIMITY:
> dev_mask = PA12203001_PX_EN_MASK;
> - ret = pa12203001_set_power_state(data, true, dev_mask);
> + ret = pa12203001_runtime_resume_and_get(data, dev_mask);
> if (ret < 0)
> return ret;
> ret = regmap_read(data->map, PA12203001_REG_PDH,
> @@ -241,9 +235,7 @@ static int pa12203001_read_raw(struct iio_dev *indio_dev,
> goto reg_err;
>
> *val = reg_byte;
> - ret = pa12203001_set_power_state(data, false, dev_mask);
> - if (ret < 0)
> - return ret;
> + pm_runtime_put_autosuspend(&data->client->dev);
> break;
> default:
> return -EINVAL;
> @@ -262,7 +254,7 @@ static int pa12203001_read_raw(struct iio_dev *indio_dev,
> }
>
> reg_err:
> - pa12203001_set_power_state(data, false, dev_mask);
> + pm_runtime_put_autosuspend(&data->client->dev);
> return ret;
> }
>