/**************************************************************************** * drivers/sensors/bmp280.c * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance with the * License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #if defined(CONFIG_I2C) && defined(CONFIG_SENSORS_BMP280) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define BMP280_ADDR 0x76 #define BMP280_FREQ CONFIG_BMP280_I2C_FREQUENCY #define DEVID 0x58 #define BMP280_DIG_T1_LSB 0x88 #define BMP280_DIG_T1_MSB 0x89 #define BMP280_DIG_T2_LSB 0x8a #define BMP280_DIG_T2_MSB 0x8b #define BMP280_DIG_T3_LSB 0x8c #define BMP280_DIG_T3_MSB 0x8d #define BMP280_DIG_P1_LSB 0x8e #define BMP280_DIG_P1_MSB 0x8f #define BMP280_DIG_P2_LSB 0x90 #define BMP280_DIG_P2_MSB 0x91 #define BMP280_DIG_P3_LSB 0x92 #define BMP280_DIG_P3_MSB 0x93 #define BMP280_DIG_P4_LSB 0x94 #define BMP280_DIG_P4_MSB 0x95 #define BMP280_DIG_P5_LSB 0x96 #define BMP280_DIG_P5_MSB 0x97 #define BMP280_DIG_P6_LSB 0x98 #define BMP280_DIG_P6_MSB 0x99 #define BMP280_DIG_P7_LSB 0x9a #define BMP280_DIG_P7_MSB 0x9b #define BMP280_DIG_P8_LSB 0x9c #define BMP280_DIG_P8_MSB 0x9d #define BMP280_DIG_P9_LSB 0x9e #define BMP280_DIG_P9_MSB 0x9f #define BMP280_DEVID 0xd0 #define BMP280_SOFT_RESET 0xe0 #define BMP280_STAT 0xf3 #define BMP280_CTRL_MEAS 0xf4 #define BMP280_CONFIG 0xf5 #define BMP280_PRESS_MSB 0xf7 #define BMP280_PRESS_LSB 0xf8 #define BMP280_PRESS_XLSB 0xf9 #define BMP280_TEMP_MSB 0xfa #define BMP280_TEMP_LSB 0xfb #define BMP280_TEMP_XLSB 0xfc /* Power modes */ #define BMP280_SLEEP_MODE (0x00) #define BMP280_FORCED_MODE (0x01) #define BMP280_NORMAL_MODE (0x03) /* Oversampling for temperature. */ #define BMP280_OST_SKIPPED (0x00 << 5) #define BMP280_OST_X1 (0x01 << 5) #define BMP280_OST_X2 (0x02 << 5) #define BMP280_OST_X4 (0x03 << 5) #define BMP280_OST_X8 (0x04 << 5) #define BMP280_OST_X16 (0x05 << 5) /* Oversampling for pressure. */ #define BMP280_OSP_SKIPPED (0x00 << 2) #define BMP280_OSP_X1 (0x01 << 2) #define BMP280_OSP_X2 (0x02 << 2) #define BMP280_OSP_X4 (0x03 << 2) #define BMP280_OSP_X8 (0x04 << 2) #define BMP280_OSP_X16 (0x05 << 2) /* Predefined oversampling combinations. */ #define BMP280_OS_ULTRA_HIGH_RES (BMP280_OSP_X16 | BMP280_OST_X2) #define BMP280_OS_STANDARD_RES (BMP280_OSP_X4 | BMP280_OST_X1) #define BMP280_OS_ULTRA_LOW_POWER (BMP280_OSP_X1 | BMP280_OST_X1) /* Data combined from bytes to int */ #define COMBINE(d) (((int)(d)[0] << 12) | ((int)(d)[1] << 4) | ((int)(d)[2] >> 4)) /**************************************************************************** * Private Type Definitions ****************************************************************************/ struct bmp280_dev_s { FAR struct sensor_lowerhalf_s sensor_lower; FAR struct i2c_master_s *i2c; /* I2C interface */ uint8_t addr; /* BMP280 I2C address */ int freq; /* BMP280 Frequency <= 3.4MHz */ bool activated; struct bmp280_calib_s { uint16_t t1; int16_t t2; int16_t t3; uint16_t p1; int16_t p2; int16_t p3; int16_t p4; int16_t p5; int16_t p6; int16_t p7; int16_t p8; int16_t p9; } calib; int32_t tempfine; }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static uint8_t bmp280_getreg8(FAR struct bmp280_dev_s *priv, uint8_t regaddr); static int bmp280_putreg8(FAR struct bmp280_dev_s *priv, uint8_t regaddr, uint8_t regval); /* Sensor methods */ static int bmp280_set_interval(FAR struct sensor_lowerhalf_s *lower, FAR unsigned int *period_us); static int bmp280_activate(FAR struct sensor_lowerhalf_s *lower, bool enable); static int bmp280_fetch(FAR struct sensor_lowerhalf_s *lower, FAR char *buffer, size_t buflen); /**************************************************************************** * Private Data ****************************************************************************/ static const struct sensor_ops_s g_sensor_ops = { .activate = bmp280_activate, .fetch = bmp280_fetch, .set_interval = bmp280_set_interval, }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: bmp280_getreg8 * * Description: * Read from an 8-bit BMP280 register * ****************************************************************************/ static uint8_t bmp280_getreg8(FAR struct bmp280_dev_s *priv, uint8_t regaddr) { struct i2c_msg_s msg[2]; uint8_t regval = 0; int ret; msg[0].frequency = priv->freq; msg[0].addr = priv->addr; msg[0].flags = 0; msg[0].buffer = ®addr; msg[0].length = 1; msg[1].frequency = priv->freq; msg[1].addr = priv->addr; msg[1].flags = I2C_M_READ; msg[1].buffer = ®val; msg[1].length = 1; ret = I2C_TRANSFER(priv->i2c, msg, 2); if (ret < 0) { snerr("I2C_TRANSFER failed: %d\n", ret); return 0; } return regval; } /**************************************************************************** * Name: bmp280_getregs * * Description: * Read two 8-bit from a BMP280 register * ****************************************************************************/ static int bmp280_getregs(FAR struct bmp280_dev_s *priv, uint8_t regaddr, uint8_t *rxbuffer, uint8_t length) { struct i2c_msg_s msg[2]; int ret; msg[0].frequency = priv->freq; msg[0].addr = priv->addr; msg[0].flags = 0; msg[0].buffer = ®addr; msg[0].length = 1; msg[1].frequency = priv->freq; msg[1].addr = priv->addr; msg[1].flags = I2C_M_READ; msg[1].buffer = rxbuffer; msg[1].length = length; ret = I2C_TRANSFER(priv->i2c, msg, 2); if (ret < 0) { snerr("I2C_TRANSFER failed: %d\n", ret); return -1; } return OK; } /**************************************************************************** * Name: bmp280_putreg8 * * Description: * Write to an 8-bit BMP280 register * ****************************************************************************/ static int bmp280_putreg8(FAR struct bmp280_dev_s *priv, uint8_t regaddr, uint8_t regval) { struct i2c_msg_s msg[2]; uint8_t txbuffer[2]; int ret; txbuffer[0] = regaddr; txbuffer[1] = regval; msg[0].frequency = priv->freq; msg[0].addr = priv->addr; msg[0].flags = 0; msg[0].buffer = txbuffer; msg[0].length = 2; ret = I2C_TRANSFER(priv->i2c, msg, 1); if (ret < 0) { snerr("I2C_TRANSFER failed: %d\n", ret); } return ret; } /**************************************************************************** * Name: bmp280_checkid * * Description: * Read and verify the BMP280 chip ID * ****************************************************************************/ static int bmp280_checkid(FAR struct bmp280_dev_s *priv) { uint8_t devid = 0; /* Read device ID */ devid = bmp280_getreg8(priv, BMP280_DEVID); up_mdelay(1); sninfo("devid: 0x%02x\n", devid); if (devid != (uint16_t) DEVID) { /* ID is not Correct */ snerr("Wrong Device ID! %02x\n", devid); return -ENODEV; } return OK; } /**************************************************************************** * Name: bmp280_set_standby * * Description: * set standby duration * ****************************************************************************/ static int bmp280_set_standby(FAR struct bmp280_dev_s *priv, uint8_t value) { uint8_t v_data_u8; uint8_t v_sb_u8; /* Set the standby duration value */ v_data_u8 = bmp280_getreg8(priv, BMP280_CONFIG); v_data_u8 = (v_data_u8 & ~(0x07 << 5)) | (value << 5); bmp280_putreg8(priv, BMP280_CONFIG, v_data_u8); /* Check the standby duration value */ v_data_u8 = bmp280_getreg8(priv, BMP280_CONFIG); v_sb_u8 = (v_data_u8 >> 5) & 0x07; if (v_sb_u8 != value) { snerr("Failed to set value for standby time."); return ERROR; } return OK; } /**************************************************************************** * Name: bmp280_initialize * * Description: * Initialize BMP280 device * ****************************************************************************/ static int bmp280_initialize(FAR struct bmp280_dev_s *priv) { uint8_t buf[24]; int ret; /* Get calibration data. */ ret = bmp280_getregs(priv, BMP280_DIG_T1_LSB, buf, 24); if (ret < 0) { return ret; } priv->calib.t1 = (uint16_t)buf[1] << 8 | buf[0]; priv->calib.t2 = (int16_t) buf[3] << 8 | buf[2]; priv->calib.t3 = (int16_t) buf[5] << 8 | buf[4]; priv->calib.p1 = (uint16_t)buf[7] << 8 | buf[6]; priv->calib.p2 = (int16_t) buf[9] << 8 | buf[8]; priv->calib.p3 = (int16_t) buf[11] << 8 | buf[10]; priv->calib.p4 = (int16_t) buf[13] << 8 | buf[12]; priv->calib.p5 = (int16_t) buf[15] << 8 | buf[14]; priv->calib.p6 = (int16_t) buf[17] << 8 | buf[16]; priv->calib.p7 = (int16_t) buf[19] << 8 | buf[18]; priv->calib.p8 = (int16_t) buf[21] << 8 | buf[20]; priv->calib.p9 = (int16_t) buf[23] << 8 | buf[22]; sninfo("T1 = %u\n", priv->calib.t1); sninfo("T2 = %d\n", priv->calib.t2); sninfo("T3 = %d\n", priv->calib.t3); sninfo("P1 = %u\n", priv->calib.p1); sninfo("P2 = %d\n", priv->calib.p2); sninfo("P3 = %d\n", priv->calib.p3); sninfo("P4 = %d\n", priv->calib.p4); sninfo("P5 = %d\n", priv->calib.p5); sninfo("P6 = %d\n", priv->calib.p6); sninfo("P7 = %d\n", priv->calib.p7); sninfo("P8 = %d\n", priv->calib.p8); sninfo("P9 = %d\n", priv->calib.p9); /* Set power mode to sleep */ bmp280_putreg8(priv, BMP280_CTRL_MEAS, BMP280_SLEEP_MODE); /* Set stand-by time to 0.5 ms, no IIR filter */ ret = bmp280_set_standby(priv, BMP280_STANDBY_05_MS); if (ret != OK) { snerr("Failed to set value for standby time.\n"); return -1; } return ret; } /**************************************************************************** * Name: bmp280_compensate * * Description: * calculate compensate tempreture * * Input Parameters: * temp - uncompensate value of tempreture. * * Returned Value: * calculate result of compensate tempreture. * ****************************************************************************/ static int32_t bmp280_compensate_temp(FAR struct bmp280_dev_s *priv, int32_t temp) { struct bmp280_calib_s *c = &priv->calib; int32_t var1; int32_t var2; var1 = ((((temp >> 3) - ((int32_t)c->t1 << 1))) * ((int32_t)c->t2)) >> 11; var2 = (((((temp >> 4) - ((int32_t)c->t1)) * ((temp >> 4) - ((int32_t)c->t1))) >> 12) * ((int32_t)c->t3)) >> 14; priv->tempfine = var1 + var2; return (priv->tempfine * 5 + 128) >> 8; } /**************************************************************************** * Name: bmp280_compensate_press * * Description: * calculate compensate pressure * * Input Parameters: * press - uncompensate value of pressure. * * Returned Value: * calculate result of compensate pressure. * ****************************************************************************/ static uint32_t bmp280_compensate_press(FAR struct bmp280_dev_s *priv, uint32_t press) { struct bmp280_calib_s *c = &priv->calib; int32_t var1; int32_t var2; uint32_t p; var1 = (priv->tempfine >> 1) - 64000; var2 = (((var1 >> 2) * (var1 >> 2)) >> 11) * ((int32_t)c->p6); var2 = var2 + ((var1 * ((int32_t)c->p5)) << 1); var2 = (var2 >> 2) + (((int32_t)c->p4) << 16); var1 = (((c->p3 * (((var1 >> 2) * (var1 >> 2)) >> 13)) >> 3) + ((((int32_t)c->p2) * var1) >> 1)) >> 18; var1 = (((32768 + var1) * ((int32_t)c->p1)) >> 15); /* avoid exception caused by division by zero */ if (var1 == 0) { return 0; } p = (((uint32_t)((0x100000) - press) - (var2 >> 12))) * 3125; if (p < 0x80000000) { p = (p << 1) / ((uint32_t)var1); } else { p = (p / (uint32_t)var1) * 2; } var1 = ((int32_t)c->p9 * ((int32_t)(((p >> 3) * (p >> 3)) >> 13))) >> 12; var2 = ((int32_t)(p >> 2) * c->p8) >> 13; p = (uint32_t)((int32_t)p + ((var1 + var2 + c->p7) >> 4)); return p; } /**************************************************************************** * Name: bmp280_set_interval ****************************************************************************/ static int bmp280_set_interval(FAR struct sensor_lowerhalf_s *lower, FAR unsigned int *period_us) { FAR struct bmp280_dev_s *priv = container_of(lower, FAR struct bmp280_dev_s, sensor_lower); int ret = 0; uint8_t regval; switch (*period_us) { case 500: regval = BMP280_STANDBY_05_MS; break; case 62500: regval = BMP280_STANDBY_63_MS; break; case 125000: regval = BMP280_STANDBY_125_MS; break; case 250000: regval = BMP280_STANDBY_250_MS; break; case 500000: regval = BMP280_STANDBY_500_MS; break; case 1000000: regval = BMP280_STANDBY_1000_MS; break; case 2000000: regval = BMP280_STANDBY_2000_MS; break; case 4000000: regval = BMP280_STANDBY_4000_MS; break; default: ret = -EINVAL; break; } if (ret == 0) { ret = bmp280_set_standby(priv, regval); } return ret; } /**************************************************************************** * Name: bmp280_activate ****************************************************************************/ static int bmp280_activate(FAR struct sensor_lowerhalf_s *lower, bool enable) { FAR struct bmp280_dev_s *priv = container_of(lower, FAR struct bmp280_dev_s, sensor_lower); int ret; if (enable) { /* Set power mode to normal and standard sampling resolution. */ ret = bmp280_putreg8(priv, BMP280_CTRL_MEAS, BMP280_NORMAL_MODE | BMP280_OS_STANDARD_RES); } else { /* Set to sleep mode */ ret = bmp280_putreg8(priv, BMP280_CTRL_MEAS, BMP280_SLEEP_MODE); } if (ret >= 0) { priv->activated = enable; } return ret; } /**************************************************************************** * Name: bmp280_fetch ****************************************************************************/ static int bmp280_fetch(FAR struct sensor_lowerhalf_s *lower, FAR char *buffer, size_t buflen) { FAR struct bmp280_dev_s *priv = container_of(lower, FAR struct bmp280_dev_s, sensor_lower); uint8_t buf[6]; uint32_t press; int32_t temp; int ret; struct timespec ts; struct sensor_event_baro baro_data; if (buflen != sizeof(baro_data)) { return -EINVAL; } if (!priv->activated) { /* Sensor is asleep, go to force mode to read once */ ret = bmp280_putreg8(priv, BMP280_CTRL_MEAS, BMP280_FORCED_MODE | BMP280_OS_ULTRA_LOW_POWER); if (ret < 0) { return ret; } /* Wait time according to ultra low power mode set during sleep */ up_mdelay(6); } /* Read pressure & data */ ret = bmp280_getregs(priv, BMP280_PRESS_MSB, buf, 6); if (ret < 0) { return ret; } press = (uint32_t)COMBINE(buf); temp = COMBINE(&buf[3]); sninfo("press = %"PRIu32", temp = %"PRIi32"\n", press, temp); temp = bmp280_compensate_temp(priv, temp); press = bmp280_compensate_press(priv, press); #ifdef CONFIG_CLOCK_MONOTONIC clock_gettime(CLOCK_MONOTONIC, &ts); #else clock_gettime(CLOCK_REALTIME, &ts); #endif baro_data.timestamp = 1000000ull * ts.tv_sec + ts.tv_nsec / 1000; baro_data.pressure = press / 100.0f; baro_data.temperature = temp / 100.0f; memcpy(buffer, &baro_data, sizeof(baro_data)); return buflen; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: bmp280_register * * Description: * Register the BMP280 character device * * Input Parameters: * devno - Instance number for driver * i2c - An instance of the I2C interface to use to communicate with * BMP280 * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ int bmp280_register(int devno, FAR struct i2c_master_s *i2c) { FAR struct bmp280_dev_s *priv; int ret; /* Initialize the BMP280 device structure */ priv = (FAR struct bmp280_dev_s *)kmm_zalloc(sizeof(struct bmp280_dev_s)); if (!priv) { snerr("Failed to allocate instance\n"); return -ENOMEM; } priv->i2c = i2c; priv->addr = BMP280_ADDR; priv->freq = BMP280_FREQ; priv->sensor_lower.ops = &g_sensor_ops; priv->sensor_lower.type = SENSOR_TYPE_BAROMETER; /* Check Device ID */ ret = bmp280_checkid(priv); if (ret < 0) { snerr("Failed to register driver: %d\n", ret); kmm_free(priv); return ret; } ret = bmp280_initialize(priv); if (ret < 0) { snerr("Failed to initialize physical device bmp280:%d\n", ret); kmm_free(priv); return ret; } /* Register the character driver */ ret = sensor_register(&priv->sensor_lower, devno); if (ret < 0) { snerr("Failed to register driver: %d\n", ret); kmm_free(priv); } sninfo("BMP280 driver loaded successfully!\n"); return ret; } #endif