hmc5883l: C port; FTI; C++ wraps C

Signed-off-by: Jon Trulson <jtrulson@ics.com>

include/fti/upm_compass.h

@@ -0,0 +1,43 @@
+/*
+ * Author: Jon Trulson <jtrulson@ics.com>
+ * Copyright (c) 2017 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifndef UPM_COMPASS_H_
+#define UPM_COMPASS_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Compass function table
+typedef struct _upm_compass_ft {
+    upm_result_t (*upm_compass_set_scale) (void* dev, float scale);
+    upm_result_t (*upm_compass_set_offset) (void* dev, float offset);
+    // returns a heading in degrees
+    upm_result_t (*upm_compass_get_value) (void* dev, float *value);
+} upm_compass_ft;
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* UPM_COMPASS_H_ */

include/upm_fti.h

@@ -125,6 +125,7 @@ typedef struct _upm_sensor_ft* (*func_get_upm_sensor_ft)(upm_sensor_t sensor_typ
 #include <fti/upm_binary.h>
 #include <fti/upm_rotaryencoder.h>
 #include <fti/upm_pressure.h>
+#include <fti/upm_compass.h>
 
 #ifdef __cplusplus
 }