On Fri, 16 Sep 2022 12:45:50 +0200
cmo@xxxxxxxxxxx wrote:
> From: Crt Mori <cmo@xxxxxxxxxxx>
>
> The sensor can operate in lower power modes and even make measurements when
> in those lower powered modes. The decision was taken that if measurement
> is not requested within 2 seconds the sensor will remain in SLEEP_STEP
> power mode, where measurements are triggered on request with setting the
> start of measurement bit (SOB). In this mode the measurements are taking
> a bit longer because we need to start it and complete it. Currently, in
> continuous mode we read ready data and this mode is activated if sensor
> measurement is requested within 2 seconds. The suspend timeout is
> increased to 6 seconds (instead of 3 before), because that enables more
> measurements in lower power mode (SLEEP_STEP), with the lowest refresh
> rate (2 seconds).
>
> Signed-off-by: Crt Mori <cmo@xxxxxxxxxxx>
Hi Crt,
I think I also mentioned switching to devm_iio_device_register().
I don't mind if that's in a follow on patch (as technically unconnected
from runtime pm) but it is something that needs tidying up now there is
nothing else in remove. Otherwise we leave this driver in a state that
I don't want anyone else copying into a new driver!
As per my reply to the cover letter, I'm unconvinced that we want to drop
the code to put the device into a low power state on remove().
We do however want to make that a problem for the devm_ infrastrucuture.
Normally this is done by adding a devm_add_action_or_reset() call
to add a callback just after we power up the chip in the first place.
That way an error path also results in us trying to leave the device
in a low power state.
Jonathan
> ---
> drivers/iio/temperature/mlx90632.c | 341 ++++++++++++++++++++++++-----
> 1 file changed, 287 insertions(+), 54 deletions(-)
>
> diff --git a/drivers/iio/temperature/mlx90632.c b/drivers/iio/temperature/mlx90632.c
> index 549c0ab5c2be..80497d9bc4e9 100644
> --- a/drivers/iio/temperature/mlx90632.c
> +++ b/drivers/iio/temperature/mlx90632.c
> @@ -6,11 +6,14 @@
>
> static int mlx90632_write_raw(struct iio_dev *indio_dev,
> @@ -902,6 +1122,7 @@ static int mlx90632_probe(struct i2c_client *client,
> mlx90632->client = client;
> mlx90632->regmap = regmap;
> mlx90632->mtyp = MLX90632_MTYP_MEDICAL;
> + mlx90632->powerstatus = MLX90632_PWR_STATUS_HALT;
>
> mutex_init(&mlx90632->lock);
> indio_dev->name = id->name;
> @@ -961,16 +1182,19 @@ static int mlx90632_probe(struct i2c_client *client,
>
> mlx90632->emissivity = 1000;
> mlx90632->object_ambient_temperature = 25000; /* 25 degrees milliCelsius */
> + mlx90632->interaction_ts = jiffies; /* Set initial value */
>
> - pm_runtime_disable(&client->dev);
> + pm_runtime_get_noresume(&client->dev);
> ret = pm_runtime_set_active(&client->dev);
> if (ret < 0) {
> mlx90632_sleep(mlx90632);
> return ret;
> }
> - pm_runtime_enable(&client->dev);
> +
> + devm_pm_runtime_enable(&client->dev);
> pm_runtime_set_autosuspend_delay(&client->dev, MLX90632_SLEEP_DELAY_MS);
> pm_runtime_use_autosuspend(&client->dev);
> + pm_runtime_put_autosuspend(&client->dev);
>
> return iio_device_register(indio_dev);
> }
> @@ -978,16 +1202,8 @@ static int mlx90632_probe(struct i2c_client *client,
> static int mlx90632_remove(struct i2c_client *client)
> {
> struct iio_dev *indio_dev = i2c_get_clientdata(client);
> - struct mlx90632_data *data = iio_priv(indio_dev);
>
> iio_device_unregister(indio_dev);
Once you reach the point where this is all that is left in
remove() you can just use devm_iio_device_register() and it'll
be cleaned up automatically + can drop remove().
It is technically an unconnected change though, so I guess it can be a follow up
patch.
> -
> - pm_runtime_disable(&client->dev);
> - pm_runtime_set_suspended(&client->dev);
> - pm_runtime_put_noidle(&client->dev);
> -
> - mlx90632_sleep(data);
> -
> return 0;
> }
>
> @@ -1003,30 +1219,47 @@ static const struct of_device_id mlx90632_of_match[] = {
> };
> MODULE_DEVICE_TABLE(of, mlx90632_of_match);
>
