Allows to configure the IIR filter coefficient and the sampling frequency
The IIR filter coefficient is exposed using the sysfs attribute
"filter_low_pass_3db_frequency"
Signed-off-by: Angel Iglesias <ang.iglesiasg@xxxxxxxxx>
---
drivers/iio/pressure/bmp280-core.c | 168 ++++++++++++++++++++++++++++-
drivers/iio/pressure/bmp280.h | 18 ----
2 files changed, 166 insertions(+), 20 deletions(-)
diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c
index 3887475a9059..3d22fc844e87 100644
--- a/drivers/iio/pressure/bmp280-core.c
+++ b/drivers/iio/pressure/bmp280-core.c
@@ -96,6 +96,27 @@ static const char *const bmp280_supply_names[] = {
"vddd", "vdda"
};
+enum bmp380_odr {
+ BMP380_ODR_200HZ,
+ BMP380_ODR_100HZ,
+ BMP380_ODR_50HZ,
+ BMP380_ODR_25HZ,
+ BMP380_ODR_12_5HZ,
+ BMP380_ODR_6_25HZ,
+ BMP380_ODR_3_125HZ,
+ BMP380_ODR_1_5625HZ,
+ BMP380_ODR_0_78HZ,
+ BMP380_ODR_0_39HZ,
+ BMP380_ODR_0_2HZ,
+ BMP380_ODR_0_1HZ,
+ BMP380_ODR_0_05HZ,
+ BMP380_ODR_0_02HZ,
+ BMP380_ODR_0_01HZ,
+ BMP380_ODR_0_006HZ,
+ BMP380_ODR_0_003HZ,
+ BMP380_ODR_0_0015HZ
+};
+
#define BMP280_NUM_SUPPLIES ARRAY_SIZE(bmp280_supply_names)
struct bmp280_data {
@@ -117,6 +138,16 @@ struct bmp280_data {
u8 oversampling_press;
u8 oversampling_temp;
u8 oversampling_humid;
+ u8 iir_filter_coeff;
+
+ /* BMP380 devices introduce sampling frequecy configuration. See
+ * datasheet sections 3.3.3. and 4.3.19.
+ *
+ * BMx280 devices allowed indirect configuration of sampling frequency
+ * changing the t_standby duration between measurements. See datasheet
+ * section 3.6.3
+ */
+ int sampling_freq;
/*
* Carryover value from temperature conversion, used in pressure
@@ -135,6 +166,12 @@ struct bmp280_chip_info {
const int *oversampling_humid_avail;
int num_oversampling_humid_avail;
+ const int *iir_filter_coeffs_avail;
+ int num_iir_filter_coeffs_avail;
+
+ const int (*sampling_freq_avail)[2];
+ int num_sampling_freq_avail;
+
int (*chip_config)(struct bmp280_data *);
int (*read_temp)(struct bmp280_data *, int *);
int (*read_press)(struct bmp280_data *, int *, int *);
@@ -185,6 +222,30 @@ static const struct iio_chan_spec bmp280_channels[] = {
},
};
+static const struct iio_chan_spec bmp380_channels[] = {
+ {
+ .type = IIO_PRESSURE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+ BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
+ },
+ {
+ .type = IIO_TEMP,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+ BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
+ },
+ {
+ .type = IIO_HUMIDITYRELATIVE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED) |
+ BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ) |
+ BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
+ },
+};
+
static int bmp280_read_calib(struct bmp280_data *data,
struct bmp280_calib *calib,
unsigned int chip)
@@ -514,6 +575,15 @@ static int bmp280_read_raw(struct iio_dev *indio_dev,
break;
}
break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = data->chip_info->sampling_freq_avail[data->sampling_freq][0];
+ *val2 = data->chip_info->sampling_freq_avail[data->sampling_freq][1];
+ ret = IIO_VAL_INT_PLUS_MICRO;
+ break;
+ case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+ *val = data->chip_info->iir_filter_coeffs_avail[data->iir_filter_coeff];
+ ret = IIO_VAL_INT;
+ break;
default:
ret = -EINVAL;
break;
@@ -577,6 +647,39 @@ static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data,
return -EINVAL;
}
+static int bmp280_write_sampling_frequency(struct bmp280_data *data,
+ int val, int val2)
+{
+ int i;
+ const int (*avail)[2] = data->chip_info->sampling_freq_avail;
+ const int n = data->chip_info->num_sampling_freq_avail;
+
+ for (i = 0; i < n; i++) {
+ if (avail[i][0] == val && avail[i][1] == val2) {
+ data->sampling_freq = i;
+
+ return data->chip_info->chip_config(data);
+ }
+ }
+ return -EINVAL;
+}
+
+static int bmp280_write_iir_filter_coeffs(struct bmp280_data *data, int val)
+{
+ int i;
+ const int *avail = data->chip_info->iir_filter_coeffs_avail;
+ const int n = data->chip_info->num_iir_filter_coeffs_avail;
+
+ for (i = 0; i < n; i++) {
+ if (avail[i] == val) {
+ data->iir_filter_coeff = i;
+
+ return data->chip_info->chip_config(data);
+ }
+ }
+ return -EINVAL;
+}
+
static int bmp280_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
@@ -606,6 +709,22 @@ static int bmp280_write_raw(struct iio_dev *indio_dev,
pm_runtime_mark_last_busy(data->dev);
pm_runtime_put_autosuspend(data->dev);
break;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ pm_runtime_get_sync(data->dev);
+ mutex_lock(&data->lock);
+ ret = bmp280_write_sampling_frequency(data, val, val2);
+ mutex_unlock(&data->lock);
+ pm_runtime_mark_last_busy(data->dev);
+ pm_runtime_put_autosuspend(data->dev);
+ break;
+ case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+ pm_runtime_get_sync(data->dev);
+ mutex_lock(&data->lock);
+ ret = bmp280_write_iir_filter_coeffs(data, val);
+ mutex_unlock(&data->lock);
+ pm_runtime_mark_last_busy(data->dev);
+ pm_runtime_put_autosuspend(data->dev);
+ break;
default:
return -EINVAL;
}
@@ -636,6 +755,17 @@ static int bmp280_read_avail(struct iio_dev *indio_dev,
}
*type = IIO_VAL_INT;
return IIO_AVAIL_LIST;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *vals = (const int *)data->chip_info->sampling_freq_avail;
+ *type = IIO_VAL_INT_PLUS_MICRO;
+ /* Values are stored in a 2D matrix */
+ *length = data->chip_info->num_sampling_freq_avail;
+ return IIO_AVAIL_LIST;
+ case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+ *vals = data->chip_info->iir_filter_coeffs_avail;
+ *type = IIO_VAL_INT;
+ *length = data->chip_info->num_iir_filter_coeffs_avail;
+ return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
@@ -749,7 +879,7 @@ static int bmp380_cmd(struct bmp280_data *data, u8 cmd)
goto failure;
}
/* wait for 2ms for command to be proccessed */
- usleep_range(2000, 2500);
+ usleep_range(data->start_up_time, data->start_up_time + 100);
/* check for command processing error */
ret = regmap_read(data->regmap, BMP380_REG_ERROR, ®);
if (ret) {
@@ -943,6 +1073,27 @@ static int bmp380_read_calib(struct bmp280_data *data,
return 0;
}
+static const int bmp380_odr_table[][2] = {
+ [BMP380_ODR_200HZ] = {200, 0},
+ [BMP380_ODR_100HZ] = {100, 0},
+ [BMP380_ODR_50HZ] = {50, 0},
+ [BMP380_ODR_25HZ] = {25, 0},
+ [BMP380_ODR_12_5HZ] = {12, 500000},
+ [BMP380_ODR_6_25HZ] = {6, 250000},
+ [BMP380_ODR_3_125HZ] = {3, 125000},
+ [BMP380_ODR_1_5625HZ] = {1, 562500},
+ [BMP380_ODR_0_78HZ] = {0, 781250},
+ [BMP380_ODR_0_39HZ] = {0, 390625},
+ [BMP380_ODR_0_2HZ] = {0, 195313},
+ [BMP380_ODR_0_1HZ] = {0, 97656},
+ [BMP380_ODR_0_05HZ] = {0, 48828},
+ [BMP380_ODR_0_02HZ] = {0, 24414},
+ [BMP380_ODR_0_01HZ] = {0, 12207},
+ [BMP380_ODR_0_006HZ] = {0, 6104},
+ [BMP380_ODR_0_003HZ] = {0, 3052},
+ [BMP380_ODR_0_0015HZ] = {0, 1526},
+};
+
static int bmp380_chip_config(struct bmp280_data *data)
{
u8 osrs;
@@ -976,7 +1127,7 @@ static int bmp380_chip_config(struct bmp280_data *data)
/* configure output data rate */
ret = regmap_write_bits(data->regmap, BMP380_REG_ODR,
- BMP380_ODRS_MASK, BMP380_ODRS_50HZ);
+ BMP380_ODRS_MASK, data->sampling_freq);
if (ret < 0) {
dev_err(data->dev, "failed to write ODR selection register\n");
return ret;
@@ -990,6 +1141,9 @@ static int bmp380_chip_config(struct bmp280_data *data)
return ret;
}
+ /* startup time wait to verify config */
+ usleep_range(data->start_up_time, data->start_up_time + 100);
+
/* check config error flag */
ret = regmap_read(data->regmap, BMP380_REG_ERROR, &tmp);
if (ret < 0) {
@@ -1007,6 +1161,7 @@ static int bmp380_chip_config(struct bmp280_data *data)
}
static const int bmp380_oversampling_avail[] = { 1, 2, 4, 8, 16, 32 };
+static const int bmp380_iir_filter_coeffs_avail[] = { 0, 1, 3, 7, 15, 31, 63, 127 };
static const struct bmp280_chip_info bmp380_chip_info = {
.oversampling_temp_avail = bmp380_oversampling_avail,
@@ -1015,6 +1170,12 @@ static const struct bmp280_chip_info bmp380_chip_info = {
.oversampling_press_avail = bmp380_oversampling_avail,
.num_oversampling_press_avail = ARRAY_SIZE(bmp380_oversampling_avail),
+ .sampling_freq_avail = bmp380_odr_table,
+ .num_sampling_freq_avail = ARRAY_SIZE(bmp380_odr_table) * 2,
+
+ .iir_filter_coeffs_avail = bmp380_iir_filter_coeffs_avail,
+ .num_iir_filter_coeffs_avail = ARRAY_SIZE(bmp380_iir_filter_coeffs_avail),
+
.chip_config = bmp380_chip_config,
.read_temp = bmp380_read_temp,
.read_press = bmp380_read_press,
@@ -1369,9 +1530,12 @@ int bmp280_common_probe(struct device *dev,
break;
case BMP380_CHIP_ID:
indio_dev->num_channels = 2;
+ indio_dev->channels = bmp380_channels;
data->chip_info = &bmp380_chip_info;
data->oversampling_press = ilog2(4);
data->oversampling_temp = ilog2(1);
+ data->iir_filter_coeff = 2;
+ data->sampling_freq = BMP380_ODR_50HZ;
data->start_up_time = 2000;
break;
default:
diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h
index b4c122525ffe..f9e21546957e 100644
--- a/drivers/iio/pressure/bmp280.h
+++ b/drivers/iio/pressure/bmp280.h
@@ -71,24 +71,6 @@
#define BMP380_OSRS_PRESS_32X BMP380_OSRS_PRESS_X(5)
#define BMP380_ODRS_MASK GENMASK(4, 0)
-#define BMP380_ODRS_200HZ 0x00
-#define BMP380_ODRS_100HZ 0x01
-#define BMP380_ODRS_50HZ 0x02
-#define BMP380_ODRS_25HZ 0x03
-#define BMP380_ODRS_12_5HZ 0x04
-#define BMP380_ODRS_6_25HZ 0x05
-#define BMP380_ODRS_3_1HZ 0x06
-#define BMP380_ODRS_1_5HZ 0x07
-#define BMP380_ODRS_0_78HZ 0x08
-#define BMP380_ODRS_0_39HZ 0x09
-#define BMP380_ODRS_0_2HZ 0x0A
-#define BMP380_ODRS_0_1HZ 0x0B
-#define BMP380_ODRS_0_05HZ 0x0C
-#define BMP380_ODRS_0_02HZ 0x0D
-#define BMP380_ODRS_0_01HZ 0x0E
-#define BMP380_ODRS_0_006HZ 0x0F
-#define BMP380_ODRS_0_003HZ 0x10
-#define BMP380_ODRS_0_0015HZ 0x11
#define BMP380_CTRL_SENSORS_MASK GENMASK(1, 0)
#define BMP380_CTRL_SENSORS_PRESS_EN BIT(0)
--
2.25.1
