src/main/drivers/accgyro/accgyro_mpu9250.c

   1 /*
   2  * This file is part of INAV.
   3  *
   4  * INAV is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * INAV is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with INAV.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include <stdbool.h>
  19 #include <stdint.h>
  20 #include <stdlib.h>
  21
  22 #include "platform.h"
  23
  24 #include "common/axis.h"
  25 #include "common/maths.h"
  26
  27 #include "drivers/system.h"
  28 #include "drivers/time.h"
  29
  30 #include "drivers/sensor.h"
  31 #include "drivers/accgyro/accgyro.h"
  32 #include "drivers/accgyro/accgyro_mpu.h"
  33 #include "drivers/accgyro/accgyro_mpu9250.h"
  34
  35 #if defined(USE_IMU_MPU9250)
  36
  37 #define MPU9250_BIT_RESET                   (0x80)
  38 #define MPU9250_BIT_INT_ANYRD_2CLEAR        (1 << 4)
  39 #define MPU9250_BIT_BYPASS_EN               (1 << 0)
  40 #define MPU9250_BIT_I2C_IF_DIS              (1 << 4)
  41 #define MPU9250_BIT_RAW_RDY_EN              (0x01)
  42
  43 static void mpu9250AccInit(accDev_t *acc)
  44 {
  45     acc->acc_1G = 512 * 4;
  46 }
  47
  48 bool mpu9250AccDetect(accDev_t *acc)
  49 {
  50     acc->busDev = busDeviceOpen(BUSTYPE_ANY, DEVHW_MPU9250, acc->imuSensorToUse);
  51     if (acc->busDev == NULL) {
  52         return false;
  53     }
  54
  55     mpuContextData_t * ctx = busDeviceGetScratchpadMemory(acc->busDev);
  56     if (ctx->chipMagicNumber != 0x9250) {
  57         return false;
  58     }
  59
  60     acc->initFn = mpu9250AccInit;
  61     acc->readFn = mpuAccReadScratchpad;
  62     acc->accAlign = acc->busDev->param;
  63
  64     return true;
  65 }
  66
  67 static void mpu9250AccAndGyroInit(gyroDev_t *gyro)
  68 {
  69     busDevice_t * dev = gyro->busDev;
  70     const gyroFilterAndRateConfig_t * config = mpuChooseGyroConfig(gyro->lpf, 1000000 / gyro->requestedSampleIntervalUs);
  71     gyro->sampleRateIntervalUs = 1000000 / config->gyroRateHz;
  72
  73     busSetSpeed(dev, BUS_SPEED_INITIALIZATION);
  74
  75     busWrite(dev, MPU_RA_PWR_MGMT_1, MPU9250_BIT_RESET);
  76     delay(100);
  77
  78     busWrite(dev, MPU_RA_SIGNAL_PATH_RESET, 0x07);      // BIT_GYRO | BIT_ACC | BIT_TEMP
  79     delay(100);
  80
  81     busWrite(dev, MPU_RA_PWR_MGMT_1, 0);
  82     delay(100);
  83
  84     busWrite(dev, MPU_RA_PWR_MGMT_1, INV_CLK_PLL);
  85     delay(15);
  86
  87     busWrite(dev, MPU_RA_GYRO_CONFIG, INV_FSR_2000DPS << 3 | FCB_DISABLED);
  88     delay(15);
  89
  90     busWrite(dev, MPU_RA_ACCEL_CONFIG, INV_FSR_16G << 3);
  91     delay(15);
  92
  93     busWrite(dev, MPU_RA_CONFIG, config->gyroConfigValues[0]);
  94     delay(15);
  95
  96     busWrite(dev, MPU_RA_SMPLRT_DIV, config->gyroConfigValues[1]);
  97     delay(100);
  98
  99     busSetSpeed(dev, BUS_SPEED_FAST);
 100 }
 101
 102 static bool mpu9250DeviceDetect(busDevice_t * dev)
 103 {
 104     uint8_t tmp;
 105     uint8_t attemptsRemaining = 5;
 106
 107     busSetSpeed(dev, BUS_SPEED_INITIALIZATION);
 108
 109     busWrite(dev, MPU_RA_PWR_MGMT_1, MPU9250_BIT_RESET);
 110
 111     do {
 112         delay(150);
 113
 114         busRead(dev, MPU_RA_WHO_AM_I, &tmp);
 115
 116         switch (tmp) {
 117             case MPU9250_WHO_AM_I_CONST:
 118             case MPU9255_WHO_AM_I_CONST:
 119                 // Compatible chip detected
 120                 return true;
 121
 122             default:
 123                 // Retry detection
 124                 break;
 125         }
 126
 127         if (!attemptsRemaining) {
 128             return false;
 129         }
 130     } while (attemptsRemaining--);
 131
 132     return false;
 133 }
 134
 135 bool mpu9250GyroDetect(gyroDev_t *gyro)
 136 {
 137     gyro->busDev = busDeviceInit(BUSTYPE_ANY, DEVHW_MPU9250, gyro->imuSensorToUse, OWNER_MPU);
 138     if (gyro->busDev == NULL) {
 139         return false;
 140     }
 141
 142     if (!mpu9250DeviceDetect(gyro->busDev)) {
 143         busDeviceDeInit(gyro->busDev);
 144         return false;
 145     }
 146
 147     // Magic number for ACC detection to indicate that we have detected MPU6000 gyro
 148     mpuContextData_t * ctx = busDeviceGetScratchpadMemory(gyro->busDev);
 149     ctx->chipMagicNumber = 0x9250;
 150
 151     gyro->initFn = mpu9250AccAndGyroInit;
 152     gyro->readFn = mpuGyroReadScratchpad;
 153     gyro->intStatusFn = gyroCheckDataReady;
 154     gyro->temperatureFn = mpuTemperatureReadScratchpad;
 155     gyro->scale = 1.0f / 16.4f;     // 16.4 dps/lsb scalefactor
 156     gyro->gyroAlign = gyro->busDev->param;
 157
 158     return true;
 159 }
 160
 161 #endif