Re: [PATCH 2/2] iio: stk3310: Export near level property for proximity sensor

[Jonathan Cameron <jic23@kernel.org>]

On Fri, 15 Apr 2022 10:50:18 +0200
Arnaud Ferraris <arnaud.ferraris@collabora.com> wrote:

> This makes the value from which an object should be considered "near"
> available to userspace. This hardware-dependent value should be set
> in the device-tree.
> 
> Signed-off-by: Arnaud Ferraris <arnaud.ferraris@collabora.com>
Hi Arnaud,

Minor request to slightly modify how you do this inline.
Otherwise looks good to me.

Thanks,

Jonathan

> ---
>  drivers/iio/light/stk3310.c | 26 ++++++++++++++++++++++++++
>  1 file changed, 26 insertions(+)
> 
> diff --git a/drivers/iio/light/stk3310.c b/drivers/iio/light/stk3310.c
> index 1d02dfbc29d1..7792456323ef 100644
> --- a/drivers/iio/light/stk3310.c
> +++ b/drivers/iio/light/stk3310.c
> @@ -106,6 +106,7 @@ struct stk3310_data {
>  	struct mutex lock;
>  	bool als_enabled;
>  	bool ps_enabled;
> +	uint32_t ps_near_level;
>  	u64 timestamp;
>  	struct regmap *regmap;
>  	struct regmap_field *reg_state;
> @@ -135,6 +136,25 @@ static const struct iio_event_spec stk3310_events[] = {
>  	},
>  };
>  
> +static ssize_t stk3310_read_near_level(struct iio_dev *indio_dev,
> +				       uintptr_t priv,
> +				       const struct iio_chan_spec *chan,
> +				       char *buf)
> +{
> +	struct stk3310_data *data = iio_priv(indio_dev);
> +
> +	return sprintf(buf, "%u\n", data->ps_near_level);
> +}
> +
> +static const struct iio_chan_spec_ext_info stk3310_ext_info[] = {
> +	{
> +		.name = "nearlevel",
> +		.shared = IIO_SEPARATE,
> +		.read = stk3310_read_near_level,
> +	},
> +	{ /* sentinel */ }
> +};
> +
>  static const struct iio_chan_spec stk3310_channels[] = {
>  	{
>  		.type = IIO_LIGHT,
> @@ -151,6 +171,7 @@ static const struct iio_chan_spec stk3310_channels[] = {
>  			BIT(IIO_CHAN_INFO_INT_TIME),
>  		.event_spec = stk3310_events,
>  		.num_event_specs = ARRAY_SIZE(stk3310_events),
> +		.ext_info = stk3310_ext_info,
>  	}
>  };
>  
> @@ -581,6 +602,11 @@ static int stk3310_probe(struct i2c_client *client,
>  	data = iio_priv(indio_dev);
>  	data->client = client;
>  	i2c_set_clientdata(client, indio_dev);
> +
> +	if (device_property_read_u32(&client->dev, "proximity-near-level",
> +				     &data->ps_near_level))
> +		data->ps_near_level = 0;

Prefer this pattern.

	data->ps_near_level = 0;
	device_property_read_u32(&client->dev, "proximity-near-level",
				 &data->ps_near_level);
taking advantage of the fact that the output won't be set unless
the property read succeeds.

> +
>  	mutex_init(&data->lock);
>  
>  	ret = stk3310_regmap_init(data);