Add reset and samplerate ioctl to HMC5883 driver

src/drivers/hmc5883/hmc5883.cpp

@@ -191,6 +191,11 @@ private:
 	 */
 	void			stop();
 
+	/**
+	 * Reset the device
+	 */
+	int			reset();
+
 	/**
 	 * Perform the on-sensor scale calibration routine.
 	 *
@@ -365,6 +370,9 @@ HMC5883::init()
 	if (I2C::init() != OK)
 		goto out;
 
+	/* reset the device configuration */
+	reset();
+
 	/* allocate basic report buffers */
 	_num_reports = 2;
 	_reports = new struct mag_report[_num_reports];
@@ -381,9 +389,6 @@ HMC5883::init()
 	if (_mag_topic < 0)
 		debug("failed to create sensor_mag object");
 
-	/* set range */
-	set_range(_range_ga);
-
 	ret = OK;
 	/* sensor is ok, but not calibrated */
 	_sensor_ok = true;
@@ -542,7 +547,6 @@ int
 HMC5883::ioctl(struct file *filp, int cmd, unsigned long arg)
 {
 	switch (cmd) {
-
 	case SENSORIOCSPOLLRATE: {
 		switch (arg) {
 
@@ -633,13 +637,15 @@ HMC5883::ioctl(struct file *filp, int cmd, unsigned long arg)
 		return _num_reports - 1;
 
 	case SENSORIOCRESET:
-		/* XXX implement this */
-		return -EINVAL;
+		return reset();
 
 	case MAGIOCSSAMPLERATE:
+		/* same as pollrate because device is in single measurement mode*/
+		return ioctl(filp, SENSORIOCSPOLLRATE, arg);
+
 	case MAGIOCGSAMPLERATE:
-		/* not supported, always 1 sample per poll */
-		return -EINVAL;
+		/* same as pollrate because device is in single measurement mode*/
+		return ioctl(filp, SENSORIOCGPOLLRATE, 0);
 
 	case MAGIOCSRANGE:
 		return set_range(arg);
@@ -702,6 +708,13 @@ HMC5883::stop()
 	work_cancel(HPWORK, &_work);
 }
 
+int
+HMC5883::reset()
+{
+	/* set range */
+	return set_range(_range_ga);
+}
+
 void
 HMC5883::cycle_trampoline(void *arg)
 {