[PATCH v2 2/3] iio: temperature: mlx90632 Read sampling frequency

From: cmo
Date: Sat Sep 03 2022 - 18:24:23 EST


From: Crt Mori <cmo@xxxxxxxxxxx>

Allow users to read sensor sampling frequency to better plan the
application measurement requests.

Signed-off-by: Crt Mori <cmo@xxxxxxxxxxx>
---
drivers/iio/temperature/mlx90632.c | 44 ++++++++++++++++++++++++++++++
1 file changed, 44 insertions(+)

diff --git a/drivers/iio/temperature/mlx90632.c b/drivers/iio/temperature/mlx90632.c
index 9acd819c76a6..37edd324d6a1 100644
--- a/drivers/iio/temperature/mlx90632.c
+++ b/drivers/iio/temperature/mlx90632.c
@@ -80,6 +80,9 @@
#define MLX90632_PWR_STATUS_CONTINUOUS MLX90632_PWR_STATUS(3) /* continuous */

#define MLX90632_EE_RR(ee_val) (ee_val & GENMASK(10, 8)) /* Only Refresh Rate bits */
+#define MLX90632_REFRESH_RATE(ee_val) (MLX90632_EE_RR(ee_val) >> 8)
+ /* Extract Refresh Rate from ee register */
+#define MLX90632_REFRESH_RATE_STATUS(refresh_rate) (refresh_rate << 8)

/* Measurement types */
#define MLX90632_MTYP_MEDICAL 0
@@ -908,6 +911,24 @@ static int mlx90632_calc_ambient_dsp105(struct mlx90632_data *data, int *val)
return ret;
}

+static int mlx90632_get_refresh_rate(struct mlx90632_data *data,
+ int *refresh_rate)
+{
+ unsigned int meas1;
+ int ret;
+
+ ret = regmap_read(data->regmap, MLX90632_EE_MEDICAL_MEAS1, &meas1);
+ if (ret < 0)
+ return ret;
+
+ *refresh_rate = MLX90632_REFRESH_RATE(meas1);
+
+ return ret;
+}
+
+static const int mlx90632_freqs[][2] = { {0, 500000}, {1, 0}, {2, 0}, {4, 0},
+ {8, 0}, {16, 0}, {32, 0}, {64, 0} };
+
static int mlx90632_pm_interraction_wakeup(struct mlx90632_data *data)
{
unsigned long now;
@@ -978,6 +999,15 @@ static int mlx90632_read_raw(struct iio_dev *indio_dev,
*val = data->object_ambient_temperature;
ret = IIO_VAL_INT;
break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ ret = mlx90632_get_refresh_rate(data, &cr);
+ if (ret < 0)
+ goto mlx90632_read_raw_pm;
+
+ *val = mlx90632_freqs[cr][0];
+ *val2 = mlx90632_freqs[cr][1];
+ ret = IIO_VAL_INT_PLUS_MICRO;
+ break;
default:
ret = -EINVAL;
break;
@@ -1012,12 +1042,24 @@ static int mlx90632_write_raw(struct iio_dev *indio_dev,
}
}

+static IIO_CONST_ATTR(sampling_frequency_available, "0.5 1 2 4 8 16 32 64");
+
+static struct attribute *mlx90632_attributes[] = {
+ &iio_const_attr_sampling_frequency_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group mlx90632_attribute_group = {
+ .attrs = mlx90632_attributes,
+};
+
static const struct iio_chan_spec mlx90632_channels[] = {
{
.type = IIO_TEMP,
.modified = 1,
.channel2 = IIO_MOD_TEMP_AMBIENT,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
},
{
.type = IIO_TEMP,
@@ -1025,12 +1067,14 @@ static const struct iio_chan_spec mlx90632_channels[] = {
.channel2 = IIO_MOD_TEMP_OBJECT,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) | BIT(IIO_CHAN_INFO_CALIBAMBIENT),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
},
};

static const struct iio_info mlx90632_info = {
.read_raw = mlx90632_read_raw,
.write_raw = mlx90632_write_raw,
+ .attrs = &mlx90632_attribute_group,
};

static int mlx90632_sleep(struct mlx90632_data *data)
--
2.34.1