From 10b40ffba2f95cdeed47b731c5ad5ecc73e140e8 Mon Sep 17 00:00:00 2001 From: Angel Iglesias Date: Tue, 13 Sep 2022 01:54:42 +0200 Subject: [PATCH] iio: pressure: bmp280: Add more tunable config parameters for BMP380 Allows sampling frequency and IIR filter coefficients configuration using sysfs ABI. The IIR filter coefficient is configurable using the sysfs attribute "filter_low_pass_3db_frequency". Signed-off-by: Angel Iglesias Link: https://lore.kernel.org/r/876f8a2277f71672488e99aa02aae4239d530f51.1663025017.git.ang.iglesiasg@gmail.com Signed-off-by: Jonathan Cameron --- drivers/iio/pressure/bmp280-core.c | 247 +++++++++++++++++++++++++++++++++++-- drivers/iio/pressure/bmp280.h | 18 --- 2 files changed, 238 insertions(+), 27 deletions(-) diff --git a/drivers/iio/pressure/bmp280-core.c b/drivers/iio/pressure/bmp280-core.c index 962f5d42..c0aff78 100644 --- a/drivers/iio/pressure/bmp280-core.c +++ b/drivers/iio/pressure/bmp280-core.c @@ -109,6 +109,27 @@ static const char *const bmp280_supply_names[] = { #define BMP280_NUM_SUPPLIES ARRAY_SIZE(bmp280_supply_names) +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, +}; + struct bmp280_data { struct device *dev; struct mutex lock; @@ -128,6 +149,17 @@ struct bmp280_data { u8 oversampling_press; u8 oversampling_temp; u8 oversampling_humid; + u8 iir_filter_coeff; + + /* + * BMP380 devices introduce sampling frequency configuration. See + * datasheet sections 3.3.3. and 4.3.19 for more details. + * + * BMx280 devices allowed indirect configuration of sampling frequency + * changing the t_standby duration between measurements, as detailed on + * section 3.6.3 of the datasheet. + */ + int sampling_freq; /* * Carryover value from temperature conversion, used in pressure @@ -155,6 +187,7 @@ struct bmp280_data { struct bmp280_chip_info { unsigned int id_reg; + const struct iio_chan_spec *channels; int num_channels; unsigned int start_up_time; @@ -170,6 +203,14 @@ struct bmp280_chip_info { int num_oversampling_humid_avail; int oversampling_humid_default; + const int *iir_filter_coeffs_avail; + int num_iir_filter_coeffs_avail; + int iir_filter_coeff_default; + + const int (*sampling_freq_avail)[2]; + int num_sampling_freq_avail; + int sampling_freq_default; + int (*chip_config)(struct bmp280_data *); int (*read_temp)(struct bmp280_data *, int *); int (*read_press)(struct bmp280_data *, int *, int *); @@ -220,6 +261,30 @@ 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 = &data->calib.bmp280; @@ -550,6 +615,25 @@ static int bmp280_read_raw(struct iio_dev *indio_dev, break; } break; + case IIO_CHAN_INFO_SAMP_FREQ: + if (!data->chip_info->sampling_freq_avail) { + ret = -EINVAL; + break; + } + + *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: + if (!data->chip_info->iir_filter_coeffs_avail) { + ret = -EINVAL; + break; + } + + *val = (1 << data->iir_filter_coeff) - 1; + ret = IIO_VAL_INT; + break; default: ret = -EINVAL; break; @@ -567,13 +651,21 @@ static int bmp280_write_oversampling_ratio_humid(struct bmp280_data *data, { const int *avail = data->chip_info->oversampling_humid_avail; const int n = data->chip_info->num_oversampling_humid_avail; + int ret, prev; int i; for (i = 0; i < n; i++) { if (avail[i] == val) { + prev = data->oversampling_humid; data->oversampling_humid = ilog2(val); - return data->chip_info->chip_config(data); + ret = data->chip_info->chip_config(data); + if (ret) { + data->oversampling_humid = prev; + data->chip_info->chip_config(data); + return ret; + } + return 0; } } return -EINVAL; @@ -584,13 +676,21 @@ static int bmp280_write_oversampling_ratio_temp(struct bmp280_data *data, { const int *avail = data->chip_info->oversampling_temp_avail; const int n = data->chip_info->num_oversampling_temp_avail; + int ret, prev; int i; for (i = 0; i < n; i++) { if (avail[i] == val) { + prev = data->oversampling_temp; data->oversampling_temp = ilog2(val); - return data->chip_info->chip_config(data); + ret = data->chip_info->chip_config(data); + if (ret) { + data->oversampling_temp = prev; + data->chip_info->chip_config(data); + return ret; + } + return 0; } } return -EINVAL; @@ -601,13 +701,71 @@ static int bmp280_write_oversampling_ratio_press(struct bmp280_data *data, { const int *avail = data->chip_info->oversampling_press_avail; const int n = data->chip_info->num_oversampling_press_avail; + int ret, prev; int i; for (i = 0; i < n; i++) { if (avail[i] == val) { + prev = data->oversampling_press; data->oversampling_press = ilog2(val); - return data->chip_info->chip_config(data); + ret = data->chip_info->chip_config(data); + if (ret) { + data->oversampling_press = prev; + data->chip_info->chip_config(data); + return ret; + } + return 0; + } + } + return -EINVAL; +} + +static int bmp280_write_sampling_frequency(struct bmp280_data *data, + int val, int val2) +{ + const int (*avail)[2] = data->chip_info->sampling_freq_avail; + const int n = data->chip_info->num_sampling_freq_avail; + int ret, prev; + int i; + + for (i = 0; i < n; i++) { + if (avail[i][0] == val && avail[i][1] == val2) { + prev = data->sampling_freq; + data->sampling_freq = i; + + ret = data->chip_info->chip_config(data); + if (ret) { + data->sampling_freq = prev; + data->chip_info->chip_config(data); + return ret; + } + return 0; + } + } + return -EINVAL; +} + +static int bmp280_write_iir_filter_coeffs(struct bmp280_data *data, int val) +{ + const int *avail = data->chip_info->iir_filter_coeffs_avail; + const int n = data->chip_info->num_iir_filter_coeffs_avail; + int ret, prev; + int i; + + for (i = 0; i < n; i++) { + if (avail[i] - 1 == val) { + prev = data->iir_filter_coeff; + data->iir_filter_coeff = i; + + ret = data->chip_info->chip_config(data); + if (ret) { + data->iir_filter_coeff = prev; + data->chip_info->chip_config(data); + return ret; + + } + return 0; } } return -EINVAL; @@ -620,6 +778,12 @@ static int bmp280_write_raw(struct iio_dev *indio_dev, struct bmp280_data *data = iio_priv(indio_dev); int ret = 0; + /* + * Helper functions to update sensor running configuration. + * If an error happens applying new settings, will try restore + * previous parameters to ensure the sensor is left in a known + * working configuration. + */ switch (mask) { case IIO_CHAN_INFO_OVERSAMPLING_RATIO: pm_runtime_get_sync(data->dev); @@ -642,6 +806,22 @@ 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; } @@ -672,6 +852,17 @@ 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; } @@ -717,6 +908,7 @@ static const int bmp280_oversampling_avail[] = { 1, 2, 4, 8, 16 }; static const struct bmp280_chip_info bmp280_chip_info = { .id_reg = BMP280_REG_ID, .start_up_time = 2000, + .channels = bmp280_channels, .num_channels = 2, .oversampling_temp_avail = bmp280_oversampling_avail, @@ -764,6 +956,7 @@ static int bme280_chip_config(struct bmp280_data *data) static const struct bmp280_chip_info bme280_chip_info = { .id_reg = BMP280_REG_ID, .start_up_time = 2000, + .channels = bmp280_channels, .num_channels = 3, .oversampling_temp_avail = bmp280_oversampling_avail, @@ -1003,6 +1196,27 @@ 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) { bool change = false, aux; @@ -1036,21 +1250,23 @@ static int bmp380_chip_config(struct bmp280_data *data) change = change || aux; /* Configure output data rate */ - ret = regmap_update_bits(data->regmap, BMP380_REG_ODR, - BMP380_ODRS_MASK, BMP380_ODRS_50HZ); + ret = regmap_update_bits_check(data->regmap, BMP380_REG_ODR, + BMP380_ODRS_MASK, data->sampling_freq, &aux); if (ret) { dev_err(data->dev, "failed to write ODR selection register\n"); return ret; } + change = change || aux; /* Set filter data */ - ret = regmap_update_bits(data->regmap, BMP380_REG_CONFIG, - BMP380_FILTER_MASK, - FIELD_PREP(BMP380_FILTER_MASK, BMP380_FILTER_3X)); + ret = regmap_update_bits_check(data->regmap, BMP380_REG_CONFIG, BMP380_FILTER_MASK, + FIELD_PREP(BMP380_FILTER_MASK, data->iir_filter_coeff), + &aux); if (ret) { dev_err(data->dev, "failed to write config register\n"); return ret; } + change = change || aux; if (change) { /* @@ -1101,10 +1317,12 @@ 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[] = { 1, 2, 4, 8, 16, 32, 64, 128}; static const struct bmp280_chip_info bmp380_chip_info = { .id_reg = BMP380_REG_ID, .start_up_time = 2000, + .channels = bmp380_channels, .num_channels = 2, .oversampling_temp_avail = bmp380_oversampling_avail, @@ -1115,6 +1333,14 @@ static const struct bmp280_chip_info bmp380_chip_info = { .num_oversampling_press_avail = ARRAY_SIZE(bmp380_oversampling_avail), .oversampling_press_default = ilog2(4), + .sampling_freq_avail = bmp380_odr_table, + .num_sampling_freq_avail = ARRAY_SIZE(bmp380_odr_table) * 2, + .sampling_freq_default = BMP380_ODR_50HZ, + + .iir_filter_coeffs_avail = bmp380_iir_filter_coeffs_avail, + .num_iir_filter_coeffs_avail = ARRAY_SIZE(bmp380_iir_filter_coeffs_avail), + .iir_filter_coeff_default = 2, + .chip_config = bmp380_chip_config, .read_temp = bmp380_read_temp, .read_press = bmp380_read_press, @@ -1356,6 +1582,7 @@ static const int bmp180_oversampling_press_avail[] = { 1, 2, 4, 8 }; static const struct bmp280_chip_info bmp180_chip_info = { .id_reg = BMP280_REG_ID, .start_up_time = 2000, + .channels = bmp280_channels, .num_channels = 2, .oversampling_temp_avail = bmp180_oversampling_temp_avail, @@ -1454,7 +1681,6 @@ int bmp280_common_probe(struct device *dev, data->dev = dev; indio_dev->name = name; - indio_dev->channels = bmp280_channels; indio_dev->info = &bmp280_info; indio_dev->modes = INDIO_DIRECT_MODE; @@ -1477,10 +1703,13 @@ int bmp280_common_probe(struct device *dev, data->chip_info = chip_info; /* Apply initial values from chip info structure */ + indio_dev->channels = chip_info->channels; indio_dev->num_channels = chip_info->num_channels; data->oversampling_press = chip_info->oversampling_press_default; data->oversampling_humid = chip_info->oversampling_humid_default; data->oversampling_temp = chip_info->oversampling_temp_default; + data->iir_filter_coeff = chip_info->iir_filter_coeff_default; + data->sampling_freq = chip_info->sampling_freq_default; data->start_up_time = chip_info->start_up_time; /* Bring up regulators */ diff --git a/drivers/iio/pressure/bmp280.h b/drivers/iio/pressure/bmp280.h index b546d77..c791325 100644 --- a/drivers/iio/pressure/bmp280.h +++ b/drivers/iio/pressure/bmp280.h @@ -54,24 +54,6 @@ #define BMP380_OSRS_PRESS_MASK GENMASK(2, 0) #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) -- 2.7.4