AP_Compass: added external compass autodetection on Navio

libraries/AP_Compass/AP_Compass.cpp

@@ -508,6 +508,22 @@ void Compass::_detect_backends(void)
         hal.console->printf("LSM9DS1: Compass not detected\n");
     }
 
+    backend = AP_Compass_HMC5843::probe(*this, hal.i2c_mgr->get_device(HAL_COMPASS_HMC5843_I2C_BUS, HAL_COMPASS_HMC5843_I2C_ADDR));
+    if (backend) {
+        _add_backend(backend);
+        hal.console->printf("HMC5843: External compass detected\n");
+    } else {
+        hal.console->printf("HMC5843: External compass not detected\n");
+    }
+#elif HAL_COMPASS_DEFAULT == HAL_COMPASS_NAVIO
+    AP_Compass_Backend *backend = AP_Compass_AK8963::probe_mpu9250(*this, 0);
+    if (backend) {
+        _add_backend(backend);
+        hal.console->printf("AK8953: Compass detected\n");
+    } else {
+        hal.console->printf("AK8953: Compass not detected\n");
+    }
+
     backend = AP_Compass_HMC5843::probe(*this, hal.i2c_mgr->get_device(HAL_COMPASS_HMC5843_I2C_BUS, HAL_COMPASS_HMC5843_I2C_ADDR));
     if (backend) {
         _add_backend(backend);

libraries/AP_HAL/AP_HAL_Boards.h

@@ -97,6 +97,7 @@
 #define HAL_COMPASS_QURT      12
 #define HAL_COMPASS_BBBMINI   13
 #define HAL_COMPASS_NAVIO2    14
+#define HAL_COMPASS_NAVIO     15
 
 // Heat Types
 #define HAL_LINUX_HEAT_PWM 1
@@ -288,7 +289,7 @@
 #define HAL_BARO_MS5611_I2C_BUS 1
 #define HAL_BARO_MS5611_I2C_ADDR 0x77
 #define HAL_BARO_MS5611_USE_TIMER false
-#define HAL_COMPASS_DEFAULT HAL_COMPASS_AK8963_MPU9250
+#define HAL_COMPASS_DEFAULT HAL_COMPASS_NAVIO
 /* HMC5843 can be an external compass */
 #define HAL_COMPASS_HMC5843_I2C_BUS 1
 #define HAL_COMPASS_HMC5843_I2C_ADDR 0x1E