diff options
| author | Michal Hanus <mikehanus@protonmail.com> | 2025-04-19 22:50:44 +0200 |
|---|---|---|
| committer | Michal Hanus <mikehanus@protonmail.com> | 2025-04-19 22:50:44 +0200 |
| commit | 9078b7ec09b135f091cb951ed234bf013c9c838e (patch) | |
| tree | ba953e144c2dd42d327a83720cdfc9fb5bb9fe34 /nrfdemo/src/bme680/bme680.c | |
| parent | 2e13c372f1419f08dab7797b244681f889dd9bcf (diff) | |
bme680 added
Diffstat (limited to 'nrfdemo/src/bme680/bme680.c')
| -rw-r--r-- | nrfdemo/src/bme680/bme680.c | 477 |
1 files changed, 477 insertions, 0 deletions
diff --git a/nrfdemo/src/bme680/bme680.c b/nrfdemo/src/bme680/bme680.c new file mode 100644 index 0000000..2a9a21d --- /dev/null +++ b/nrfdemo/src/bme680/bme680.c @@ -0,0 +1,477 @@ +/* bme680.c - Driver for Bosch Sensortec's BME680 temperature, pressure, + * humidity and gas sensor + * + * https://www.bosch-sensortec.com/bst/products/all_products/bme680 + */ + +/* + * Copyright (c) 2018 Bosch Sensortec GmbH + * Copyright (c) 2022, Leonard Pollak + * + * SPDX-License-Identifier: Apache-2.0 + */ + +#include <zephyr/drivers/gpio.h> +#include <zephyr/init.h> +#include <zephyr/kernel.h> +#include <zephyr/sys/byteorder.h> +#include <zephyr/sys/__assert.h> +#include <zephyr/drivers/sensor.h> +#include <zephyr/logging/log.h> + +#include "bme680.h" + +LOG_MODULE_REGISTER(bme680, CONFIG_SENSOR_LOG_LEVEL); + + +#if BME680_BUS_SPI +static inline bool bme680_is_on_spi(const struct device *dev) +{ + const struct bme680_config *config = dev->config; + + return config->bus_io == &bme680_bus_io_spi; +} +#endif + +static inline int bme680_bus_check(const struct device *dev) +{ + const struct bme680_config *config = dev->config; + + return config->bus_io->check(&config->bus); +} + +static inline int bme680_reg_read(const struct device *dev, + uint8_t start, uint8_t *buf, int size) +{ + const struct bme680_config *config = dev->config; + + return config->bus_io->read(dev, start, buf, size); +} + +static inline int bme680_reg_write(const struct device *dev, uint8_t reg, + uint8_t val) +{ + const struct bme680_config *config = dev->config; + + return config->bus_io->write(dev, reg, val); +} + +static void bme680_calc_temp(struct bme680_data *data, uint32_t adc_temp) +{ + int64_t var1, var2, var3; + + var1 = ((int32_t)adc_temp >> 3) - ((int32_t)data->par_t1 << 1); + var2 = (var1 * (int32_t)data->par_t2) >> 11; + var3 = ((var1 >> 1) * (var1 >> 1)) >> 12; + var3 = ((var3) * ((int32_t)data->par_t3 << 4)) >> 14; + data->t_fine = var2 + var3; + data->calc_temp = ((data->t_fine * 5) + 128) >> 8; +} + +static void bme680_calc_press(struct bme680_data *data, uint32_t adc_press) +{ + int32_t var1, var2, var3, calc_press; + + var1 = (((int32_t)data->t_fine) >> 1) - 64000; + var2 = ((((var1 >> 2) * (var1 >> 2)) >> 11) * + (int32_t)data->par_p6) >> 2; + var2 = var2 + ((var1 * (int32_t)data->par_p5) << 1); + var2 = (var2 >> 2) + ((int32_t)data->par_p4 << 16); + var1 = (((((var1 >> 2) * (var1 >> 2)) >> 13) * + ((int32_t)data->par_p3 << 5)) >> 3) + + (((int32_t)data->par_p2 * var1) >> 1); + var1 = var1 >> 18; + var1 = ((32768 + var1) * (int32_t)data->par_p1) >> 15; + calc_press = 1048576 - adc_press; + calc_press = (calc_press - (var2 >> 12)) * ((uint32_t)3125); + /* This max value is used to provide precedence to multiplication or + * division in the pressure calculation equation to achieve least + * loss of precision and avoiding overflows. + * i.e Comparing value, signed int 32bit (1 << 30) + */ + if (calc_press >= (int32_t)0x40000000) { + calc_press = ((calc_press / var1) << 1); + } else { + calc_press = ((calc_press << 1) / var1); + } + var1 = ((int32_t)data->par_p9 * + (int32_t)(((calc_press >> 3) + * (calc_press >> 3)) >> 13)) >> 12; + var2 = ((int32_t)(calc_press >> 2) * (int32_t)data->par_p8) >> 13; + var3 = ((int32_t)(calc_press >> 8) * (int32_t)(calc_press >> 8) + * (int32_t)(calc_press >> 8) + * (int32_t)data->par_p10) >> 17; + + data->calc_press = calc_press + + ((var1 + var2 + var3 + + ((int32_t)data->par_p7 << 7)) >> 4); +} + +static void bme680_calc_humidity(struct bme680_data *data, uint16_t adc_humidity) +{ + int32_t var1, var2_1, var2_2, var2, var3, var4, var5, var6; + int32_t temp_scaled, calc_hum; + + temp_scaled = (((int32_t)data->t_fine * 5) + 128) >> 8; + var1 = (int32_t)(adc_humidity - ((int32_t)((int32_t)data->par_h1 * 16))) - + (((temp_scaled * (int32_t)data->par_h3) + / ((int32_t)100)) >> 1); + var2_1 = (int32_t)data->par_h2; + var2_2 = ((temp_scaled * (int32_t)data->par_h4) / (int32_t)100) + + (((temp_scaled * ((temp_scaled * (int32_t)data->par_h5) + / ((int32_t)100))) >> 6) / ((int32_t)100)) + + (int32_t)(1 << 14); + var2 = (var2_1 * var2_2) >> 10; + var3 = var1 * var2; + var4 = (int32_t)data->par_h6 << 7; + var4 = ((var4) + ((temp_scaled * (int32_t)data->par_h7) / + ((int32_t)100))) >> 4; + var5 = ((var3 >> 14) * (var3 >> 14)) >> 10; + var6 = (var4 * var5) >> 1; + calc_hum = (((var3 + var6) >> 10) * ((int32_t)1000)) >> 12; + + if (calc_hum > 100000) { /* Cap at 100%rH */ + calc_hum = 100000; + } else if (calc_hum < 0) { + calc_hum = 0; + } + + data->calc_humidity = calc_hum; +} + +static void bme680_calc_gas_resistance(struct bme680_data *data, uint8_t gas_range, + uint16_t adc_gas_res) +{ + int64_t var1, var3; + uint64_t var2; + + static const uint32_t look_up1[16] = { 2147483647, 2147483647, 2147483647, + 2147483647, 2147483647, 2126008810, 2147483647, + 2130303777, 2147483647, 2147483647, 2143188679, + 2136746228, 2147483647, 2126008810, 2147483647, + 2147483647 }; + + static const uint32_t look_up2[16] = { 4096000000, 2048000000, 1024000000, + 512000000, 255744255, 127110228, 64000000, + 32258064, 16016016, 8000000, 4000000, 2000000, + 1000000, 500000, 250000, 125000 }; + + var1 = (int64_t)((1340 + (5 * (int64_t)data->range_sw_err)) * + ((int64_t)look_up1[gas_range])) >> 16; + var2 = (((int64_t)((int64_t)adc_gas_res << 15) - (int64_t)(16777216)) + var1); + var3 = (((int64_t)look_up2[gas_range] * (int64_t)var1) >> 9); + data->calc_gas_resistance = (uint32_t)((var3 + ((int64_t)var2 >> 1)) + / (int64_t)var2); +} + +static uint8_t bme680_calc_res_heat(struct bme680_data *data, uint16_t heatr_temp) +{ + uint8_t heatr_res; + int32_t var1, var2, var3, var4, var5; + int32_t heatr_res_x100; + int32_t amb_temp = 25; /* Assume ambient temperature to be 25 deg C */ + + if (heatr_temp > 400) { /* Cap temperature */ + heatr_temp = 400; + } + + var1 = ((amb_temp * data->par_gh3) / 1000) * 256; + var2 = (data->par_gh1 + 784) * (((((data->par_gh2 + 154009) + * heatr_temp * 5) / 100) + + 3276800) / 10); + var3 = var1 + (var2 / 2); + var4 = (var3 / (data->res_heat_range + 4)); + var5 = (131 * data->res_heat_val) + 65536; + heatr_res_x100 = ((var4 / var5) - 250) * 34; + heatr_res = (heatr_res_x100 + 50) / 100; + + return heatr_res; +} + +static uint8_t bme680_calc_gas_wait(uint16_t dur) +{ + uint8_t factor = 0, durval; + + if (dur >= 0xfc0) { + durval = 0xff; /* Max duration*/ + } else { + while (dur > 0x3F) { + dur = dur / 4; + factor += 1; + } + durval = dur + (factor * 64); + } + + return durval; +} + +static int bme680_sample_fetch(const struct device *dev, + enum sensor_channel chan) +{ + struct bme680_data *data = dev->data; + uint8_t buff[BME680_LEN_FIELD] = { 0 }; + uint8_t gas_range; + uint32_t adc_temp, adc_press; + uint16_t adc_hum, adc_gas_res; + int size = BME680_LEN_FIELD; + int ret; + + __ASSERT_NO_MSG(chan == SENSOR_CHAN_ALL); + + ret = bme680_reg_read(dev, BME680_REG_FIELD0, buff, size); + if (ret < 0) { + return ret; + } + + data->new_data = buff[0] & BME680_MSK_NEW_DATA; + data->heatr_stab = buff[14] & BME680_MSK_HEATR_STAB; + + adc_press = (uint32_t)(((uint32_t)buff[2] << 12) | ((uint32_t)buff[3] << 4) + | ((uint32_t)buff[4] >> 4)); + adc_temp = (uint32_t)(((uint32_t)buff[5] << 12) | ((uint32_t)buff[6] << 4) + | ((uint32_t)buff[7] >> 4)); + adc_hum = (uint16_t)(((uint32_t)buff[8] << 8) | (uint32_t)buff[9]); + adc_gas_res = (uint16_t)((uint32_t)buff[13] << 2 | (((uint32_t)buff[14]) >> 6)); + gas_range = buff[14] & BME680_MSK_GAS_RANGE; + + if (data->new_data) { + bme680_calc_temp(data, adc_temp); + bme680_calc_press(data, adc_press); + bme680_calc_humidity(data, adc_hum); + bme680_calc_gas_resistance(data, gas_range, adc_gas_res); + } + + /* Trigger the next measurement */ + ret = bme680_reg_write(dev, BME680_REG_CTRL_MEAS, + BME680_CTRL_MEAS_VAL); + if (ret < 0) { + return ret; + } + + return 0; +} + +static int bme680_channel_get(const struct device *dev, + enum sensor_channel chan, + struct sensor_value *val) +{ + struct bme680_data *data = dev->data; + + switch (chan) { + case SENSOR_CHAN_AMBIENT_TEMP: + /* + * data->calc_temp has a resolution of 0.01 degC. + * So 5123 equals 51.23 degC. + */ + val->val1 = data->calc_temp / 100; + val->val2 = data->calc_temp % 100 * 10000; + break; + case SENSOR_CHAN_PRESS: + /* + * data->calc_press has a resolution of 1 Pa. + * So 96321 equals 96.321 kPa. + */ + val->val1 = data->calc_press / 1000; + val->val2 = (data->calc_press % 1000) * 1000; + break; + case SENSOR_CHAN_HUMIDITY: + /* + * data->calc_humidity has a resolution of 0.001 %RH. + * So 46333 equals 46.333 %RH. + */ + val->val1 = data->calc_humidity / 1000; + val->val2 = (data->calc_humidity % 1000) * 1000; + break; + case SENSOR_CHAN_GAS_RES: + /* + * data->calc_gas_resistance has a resolution of 1 ohm. + * So 100000 equals 100000 ohms. + */ + val->val1 = data->calc_gas_resistance; + val->val2 = 0; + break; + default: + return -ENOTSUP; + } + + return 0; +} + +static int bme680_read_compensation(const struct device *dev) +{ + struct bme680_data *data = dev->data; + uint8_t buff[BME680_LEN_COEFF_ALL]; + int err = 0; + + err = bme680_reg_read(dev, BME680_REG_COEFF1, buff, BME680_LEN_COEFF1); + if (err < 0) { + return err; + } + + err = bme680_reg_read(dev, BME680_REG_COEFF2, &buff[BME680_LEN_COEFF1], + BME680_LEN_COEFF2); + if (err < 0) { + return err; + } + + err = bme680_reg_read(dev, BME680_REG_COEFF3, + &buff[BME680_LEN_COEFF1 + BME680_LEN_COEFF2], + BME680_LEN_COEFF3); + if (err < 0) { + return err; + } + + /* Temperature related coefficients */ + data->par_t1 = (uint16_t)(BME680_CONCAT_BYTES(buff[32], buff[31])); + data->par_t2 = (int16_t)(BME680_CONCAT_BYTES(buff[1], buff[0])); + data->par_t3 = (uint8_t)(buff[2]); + + /* Pressure related coefficients */ + data->par_p1 = (uint16_t)(BME680_CONCAT_BYTES(buff[5], buff[4])); + data->par_p2 = (int16_t)(BME680_CONCAT_BYTES(buff[7], buff[6])); + data->par_p3 = (int8_t)buff[8]; + data->par_p4 = (int16_t)(BME680_CONCAT_BYTES(buff[11], buff[10])); + data->par_p5 = (int16_t)(BME680_CONCAT_BYTES(buff[13], buff[12])); + data->par_p6 = (int8_t)(buff[15]); + data->par_p7 = (int8_t)(buff[14]); + data->par_p8 = (int16_t)(BME680_CONCAT_BYTES(buff[19], buff[18])); + data->par_p9 = (int16_t)(BME680_CONCAT_BYTES(buff[21], buff[20])); + data->par_p10 = (uint8_t)(buff[22]); + + /* Humidity related coefficients */ + data->par_h1 = (uint16_t)(((uint16_t)buff[25] << 4) | (buff[24] & 0x0f)); + data->par_h2 = (uint16_t)(((uint16_t)buff[23] << 4) | ((buff[24]) >> 4)); + data->par_h3 = (int8_t)buff[26]; + data->par_h4 = (int8_t)buff[27]; + data->par_h5 = (int8_t)buff[28]; + data->par_h6 = (uint8_t)buff[29]; + data->par_h7 = (int8_t)buff[30]; + + /* Gas heater related coefficients */ + data->par_gh1 = (int8_t)buff[35]; + data->par_gh2 = (int16_t)(BME680_CONCAT_BYTES(buff[34], buff[33])); + data->par_gh3 = (int8_t)buff[36]; + + data->res_heat_val = (int8_t)buff[37]; + data->res_heat_range = ((buff[39] & BME680_MSK_RH_RANGE) >> 4); + data->range_sw_err = ((int8_t)(buff[41] & BME680_MSK_RANGE_SW_ERR)) / 16; + + return 0; +} + +static int bme680_init(const struct device *dev) +{ + struct bme680_data *data = dev->data; + int err; + + err = bme680_bus_check(dev); + if (err < 0) { + LOG_ERR("Bus not ready for '%s'", dev->name); + return err; + } + +#if BME680_BUS_SPI + if (bme680_is_on_spi(dev)) { + uint8_t mem_page; + + err = bme680_reg_read(dev, BME680_REG_STATUS, &mem_page, 1); + if (err < 0) { + return err; + } + + data->mem_page = (mem_page & BME680_SPI_MEM_PAGE_MSK) >> BME680_SPI_MEM_PAGE_POS; + } +#endif + + err = bme680_reg_read(dev, BME680_REG_CHIP_ID, &data->chip_id, 1); + if (err < 0) { + return err; + } + + if (data->chip_id == BME680_CHIP_ID) { + LOG_DBG("BME680 chip detected"); + } else { + LOG_ERR("Bad BME680 chip id: 0x%x", data->chip_id); + return -ENOTSUP; + } + + err = bme680_read_compensation(dev); + if (err < 0) { + return err; + } + + err = bme680_reg_write(dev, BME680_REG_CTRL_HUM, BME680_HUMIDITY_OVER); + if (err < 0) { + return err; + } + + err = bme680_reg_write(dev, BME680_REG_CONFIG, BME680_CONFIG_VAL); + if (err < 0) { + return err; + } + + err = bme680_reg_write(dev, BME680_REG_CTRL_GAS_1, + BME680_CTRL_GAS_1_VAL); + if (err < 0) { + return err; + } + + err = bme680_reg_write(dev, BME680_REG_RES_HEAT0, + bme680_calc_res_heat(data, BME680_HEATR_TEMP)); + if (err < 0) { + return err; + } + + err = bme680_reg_write(dev, BME680_REG_GAS_WAIT0, + bme680_calc_gas_wait(BME680_HEATR_DUR_MS)); + if (err < 0) { + return err; + } + + err = bme680_reg_write(dev, BME680_REG_CTRL_MEAS, + BME680_CTRL_MEAS_VAL); + + return err; +} + +static const struct sensor_driver_api bme680_api_funcs = { + .sample_fetch = bme680_sample_fetch, + .channel_get = bme680_channel_get, +}; + +/* Initializes a struct bme680_config for an instance on a SPI bus. */ +#define BME680_CONFIG_SPI(inst) \ + { \ + .bus.spi = SPI_DT_SPEC_INST_GET( \ + inst, BME680_SPI_OPERATION, 0), \ + .bus_io = &bme680_bus_io_spi, \ + } + +/* Initializes a struct bme680_config for an instance on an I2C bus. */ +#define BME680_CONFIG_I2C(inst) \ + { \ + .bus.i2c = I2C_DT_SPEC_INST_GET(inst), \ + .bus_io = &bme680_bus_io_i2c, \ + } + +/* + * Main instantiation macro, which selects the correct bus-specific + * instantiation macros for the instance. + */ +#define BME680_DEFINE(inst) \ + static struct bme680_data bme680_data_##inst; \ + static const struct bme680_config bme680_config_##inst = \ + COND_CODE_1(DT_INST_ON_BUS(inst, spi), \ + (BME680_CONFIG_SPI(inst)), \ + (BME680_CONFIG_I2C(inst))); \ + SENSOR_DEVICE_DT_INST_DEFINE(inst, \ + bme680_init, \ + NULL, \ + &bme680_data_##inst, \ + &bme680_config_##inst, \ + POST_KERNEL, \ + CONFIG_SENSOR_INIT_PRIORITY, \ + &bme680_api_funcs); + +/* Create the struct device for every status "okay" node in the devicetree. */ +DT_INST_FOREACH_STATUS_OKAY(BME680_DEFINE) |
