L3GD20: Make this sensor push data onto a FreeRTOS queue so that the sensor

reading task can block according.  Also now the gyro data is sent to
stabilization multiple times per update of the attitude loop.

flight/Modules/Attitude/attitude.c

@@ -252,11 +252,10 @@ static void AttitudeTask(void *parameters)
 			GyrosSet(&gyros);
 			AlarmsClear(SYSTEMALARMS_ALARM_ATTITUDE);
 		}
+	}
+}
 
-		if(cc3d)
+float gyros_passed[3];
-			vTaskDelayUntil(&lastSysTime, 3);
-	}
-}
 
 /**
  * Get an update from the sensors
@@ -350,6 +349,10 @@ static int32_t updateSensors(AccelsData * accels, GyrosData * gyros)
 	// and make it average zero (weakly)
 	gyro_correct_int[2] += - gyros->z * yawBiasRate;
 
+	gyros_passed[0] = gyros->x;
+	gyros_passed[1] = gyros->y;
+	gyros_passed[2] = gyros->z;
+
 	return 0;
 }
 
@@ -364,12 +367,68 @@ static int32_t updateSensorsCC3D(AccelsData * accelsData, GyrosData * gyrosData)
 {
 	static portTickType lastSysTime;
 	uint32_t accel_samples = 0;
-	uint32_t gyro_samples = 0;
 	int32_t accel_accum[3] = {0, 0, 0};
-	int32_t gyro_accum[3] = {0,0,0};
 	float gyro_scaling = 1;
+	float gyros_accum[3] = {0, 0, 0};
 	float accel_scaling = 1;
 
+#if defined(PIOS_INCLUDE_L3GD20)
+	xQueueHandle gyro_queue = PIOS_L3GD20_GetQueue();
+	struct pios_l3gd20_data gyro;
+	gyro_scaling = PIOS_L3GD20_GetScale();
+
+	if(xQueueReceive(gyro_queue, (void *) &gyro, 3) == errQUEUE_EMPTY) {
+		// Unfortunately if the L3GD20 ever misses getting read, then it will not
+		// trigger more interrupts.  In this case we must force a read to kickstart
+		// it.
+		PIOS_L3GD20_ReadGyros(&gyro);	
+		AlarmsSet(SYSTEMALARMS_ALARM_ATTITUDE, SYSTEMALARMS_ALARM_ERROR);
+		return -1;
+	}
+
+	gyrosData->x = gyro.gyro_x * gyro_scaling;
+	gyrosData->y = -gyro.gyro_y * gyro_scaling;
+	gyrosData->z = -gyro.gyro_z * gyro_scaling;
+	gyrosData->temperature = 0;
+	GyrosSet(gyrosData);
+
+	gyros_accum[0] = gyrosData->x;
+	gyros_accum[1] = gyrosData->y;
+	gyros_accum[2] = gyrosData->z;
+	
+	if(xQueueReceive(gyro_queue, (void * const) &gyro, 3) == errQUEUE_EMPTY) {
+		AlarmsSet(SYSTEMALARMS_ALARM_ATTITUDE, SYSTEMALARMS_ALARM_ERROR);
+		return -1;
+	}
+
+	gyrosData->x = gyro.gyro_x * gyro_scaling;
+	gyrosData->y = -gyro.gyro_y * gyro_scaling;
+	gyrosData->z = -gyro.gyro_z * gyro_scaling;
+	gyrosData->temperature = 0;
+
+	gyros_accum[0] += gyrosData->x;
+	gyros_accum[1] += gyrosData->y;
+	gyros_accum[2] += gyrosData->z;
+
+	if(xQueueReceive(gyro_queue, (void * const) &gyro, 3) == errQUEUE_EMPTY) {
+		AlarmsSet(SYSTEMALARMS_ALARM_ATTITUDE, SYSTEMALARMS_ALARM_ERROR);
+		return -1;
+	}
+	
+	gyrosData->x = gyro.gyro_x * gyro_scaling;
+	gyrosData->y = -gyro.gyro_y * gyro_scaling;
+	gyrosData->z = -gyro.gyro_z * gyro_scaling;
+	gyrosData->temperature = 0;
+
+	gyros_accum[0] += gyrosData->x;
+	gyros_accum[1] += gyrosData->y;
+	gyros_accum[2] += gyrosData->z;
+	
+	gyros_passed[0] = gyros_accum[0] / 3;
+	gyros_passed[1] = gyros_accum[1] / 3;
+	gyros_passed[2] = gyros_accum[2] / 3;
+#endif	
+
 #if defined(PIOS_INCLUDE_BMA180)
 	struct pios_bma180_data accel;
 	accel_samples = 0;
@@ -398,47 +457,12 @@ static int32_t updateSensorsCC3D(AccelsData * accelsData, GyrosData * gyrosData)
 	accel_scaling = PIOS_BMA180_GetScale();
 #endif
 	
-#if defined(PIOS_INCLUDE_L3GD20)
-	struct pios_l3gd20_data gyro;
-	int32_t gyro_read_good;
-	gyro_samples = 0;
-	bool gyro_error = false;
-
-	while((gyro_read_good = PIOS_L3GD20_ReadFifo(&gyro) != 0) && !gyro_error)
-		gyro_error = ((xTaskGetTickCount() - lastSysTime) > 5) ? true : gyro_error;
-	if (gyro_error) {
-		// Unfortunately if the L3GD20 ever misses getting read, then it will not
-		// trigger more interrupts.  In this case we must force a read to kickstart
-		// it.
-		PIOS_L3GD20_ReadGyros(&gyro);
-		lastSysTime = xTaskGetTickCount();
-		return -1;
-	}
-
-	while(gyro_read_good == 0) {
-		gyro_samples++;
-		
-		gyro_accum[0] += gyro.gyro_x;
-		gyro_accum[1] += gyro.gyro_y;
-		gyro_accum[2] += gyro.gyro_z;
-		
-		gyro_read_good = PIOS_L3GD20_ReadFifo(&gyro);
-	}
-	gyro_scaling = PIOS_L3GD20_GetScale();
-#endif	
-
 	float accels[3] = {(float) -accel_accum[1] / accel_samples, (float) -accel_accum[0] / accel_samples, -(float) accel_accum[2] / accel_samples};
 	
 	accelsData->x = accels[0] * accel_scaling - accelbias[0];
 	accelsData->y = accels[1] * accel_scaling - accelbias[1];
 	accelsData->z = accels[2] * accel_scaling - accelbias[2];
 	
-	float gyros[3] = {(float) gyro_accum[0] / gyro_samples, (float) -gyro_accum[1] / gyro_samples, -(float) gyro_accum[2] / gyro_samples};
-	
-	gyrosData->x = gyros[0] * gyro_scaling;
-	gyrosData->y = gyros[1] * gyro_scaling;
-	gyrosData->z = gyros[2] * gyro_scaling;
-
 	lastSysTime = xTaskGetTickCount();
 	
 	return 0;
@@ -454,7 +478,7 @@ static void updateAttitude(AccelsData * accelsData, GyrosData * gyrosData)
 	lastSysTime = thisSysTime;
 	
 	// Bad practice to assume structure order, but saves memory
-	float * gyros = &gyrosData->x;
+	float * gyros = gyros_passed;
 	float * accels = &accelsData->x;
 	
 	float grot[3];

flight/Modules/Sensors/sensors.c

@@ -270,22 +270,17 @@ static void SensorsTask(void *parameters)
 // Using L3DG20 gyro
 #elif defined(PIOS_INCLUDE_L3GD20)
 		struct pios_l3gd20_data gyro;
-		count = 0;
+		gyro_samples = 0;
-		while((read_good = PIOS_L3GD20_ReadFifo(&gyro)) != 0 && !error)
+		xQueueHandle gyro_queue = PIOS_L3GD20_GetQueue();
-			error = ((xTaskGetTickCount() - lastSysTime) > SENSOR_PERIOD) ? true : error;
-		if (error)
-			continue;
-		while(read_good == 0) {
-			count++;
 		
+		while(xQueueReceive(gyro_queue, (void *) &gyro, 0) != errQUEUE_EMPTY) {
+			gyro_samples++;
 			gyro_accum[0] += gyro.gyro_x;
 			gyro_accum[1] += gyro.gyro_y;
 			gyro_accum[2] += gyro.gyro_z;
 			
 			read_good = PIOS_L3GD20_ReadFifo(&gyro);
 		}
-				
-		gyro_samples = count;
 		gyro_scaling = PIOS_L3GD20_GetScale();
 
 #else

flight/PiOS/Common/pios_l3gd20.c

@@ -41,12 +41,11 @@ enum pios_l3gd20_dev_magic {
 	PIOS_L3GD20_DEV_MAGIC = 0x9d39bced,
 };
 
-#define PIOS_L3GD20_MAX_DOWNSAMPLE 10
+#define PIOS_L3GD20_MAX_DOWNSAMPLE 2
 struct l3gd20_dev {
 	uint32_t spi_id;
 	uint32_t slave_num;
-	int16_t buffer[PIOS_L3GD20_MAX_DOWNSAMPLE * sizeof(struct pios_l3gd20_data)];
+	xQueueHandle queue;
-	t_fifo_buffer fifo;
 	const struct pios_l3gd20_cfg * cfg;
 	enum pios_l3gd20_filter bandwidth;
 	enum pios_l3gd20_range range;
@@ -81,9 +80,14 @@ static struct l3gd20_dev * PIOS_L3GD20_alloc(void)
 	l3gd20_dev = (struct l3gd20_dev *)pvPortMalloc(sizeof(*l3gd20_dev));
 	if (!l3gd20_dev) return (NULL);
 
-	fifoBuf_init(&l3gd20_dev->fifo, (uint8_t *) l3gd20_dev->buffer, sizeof(l3gd20_dev->buffer));
-	
 	l3gd20_dev->magic = PIOS_L3GD20_DEV_MAGIC;
+
+	l3gd20_dev->queue = xQueueCreate(PIOS_L3GD20_MAX_DOWNSAMPLE, sizeof(struct pios_l3gd20_data));
+	if(l3gd20_dev->queue == NULL) {
+		vPortFree(l3gd20_dev);
+		return NULL;
+	}
+
 	return(l3gd20_dev);
 }
 
@@ -301,24 +305,15 @@ int32_t PIOS_L3GD20_ReadID()
 }
 
 /**
- * \brief Reads the data from the MPU6050 FIFO
+ * \brief Reads the queue handle
- * \param[out] buffer destination buffer
+ * \return Handle to the queue or null if invalid device
- * \param[in] len maximum number of bytes which should be read
- * \note This returns the data as X, Y, Z the temperature
- * \return number of bytes transferred if operation was successful
- * \return -1 if error during I2C transfer
  */
-int32_t PIOS_L3GD20_ReadFifo(struct pios_l3gd20_data * buffer)
+xQueueHandle PIOS_L3GD20_GetQueue()
 {
 	if(PIOS_L3GD20_Validate(dev) != 0)
-		return -1;
+		return (xQueueHandle) NULL;
 
-	if(fifoBuf_getUsed(&dev->fifo) < sizeof(*buffer))
+	return dev->queue;
-		return -1;
-		
-	fifoBuf_getData(&dev->fifo, (uint8_t *) buffer, sizeof(*buffer));
-	
-	return 0;
 }
 
 float PIOS_L3GD20_GetScale() 
@@ -380,11 +375,7 @@ void PIOS_L3GD20_IRQHandler(void)
 	memcpy((uint8_t *) &(data.gyro_x), &rec[1], 6);
 	data.temperature = PIOS_L3GD20_GetReg(PIOS_L3GD20_OUT_TEMP);
 	
-	if(fifoBuf_getFree(&dev->fifo) < sizeof(data)) {
+	xQueueSend(dev->queue, (void *) &data, 0);
-		return;	
-	}
-	
-	fifoBuf_putData(&dev->fifo, (uint8_t *) &data, sizeof(data));
 }
 
 #endif /* L3GD20 */

flight/PiOS/inc/pios_l3gd20.h

@@ -135,7 +135,7 @@ struct pios_l3gd20_cfg {
 
 /* Public Functions */
 extern int32_t PIOS_L3GD20_Init(uint32_t spi_id, uint32_t slave_num, const struct pios_l3gd20_cfg * cfg);
-extern int32_t PIOS_L3GD20_ReadFifo(struct pios_l3gd20_data * buffer);
+extern xQueueHandle PIOS_L3GD20_GetQueue();
 extern int32_t PIOS_L3GD20_ReadGyros(struct pios_l3gd20_data * buffer);
 extern int32_t PIOS_L3GD20_SetRange(enum pios_l3gd20_range range);
 extern float PIOS_L3GD20_GetScale();