iio: proximity: stk3310: Export near level property for proximity sensor

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>
Link: https://lore.kernel.org/r/20220420112540.91907-3-arnaud.ferraris@collabora.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/light/stk3310.c b/drivers/iio/light/stk3310.c
index 1d02dfbc29d1a76e96bd226d9b70cb599b580138..b578b46276cc7e4b06d1bf31f1cac7b3ae3ffcb5 100644 (file)
--- 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 +602,10 @@ static int stk3310_probe(struct i2c_client *client,
        data = iio_priv(indio_dev);
        data->client = client;
        i2c_set_clientdata(client, indio_dev);
+
+       device_property_read_u32(&client->dev, "proximity-near-level",
+                                &data->ps_near_level);
+
        mutex_init(&data->lock);
 
        ret = stk3310_regmap_init(data);