nunchuck: C port; FTI; C++ wraps C

Some API changes were made as well, see docs/apichanges.md.

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

src/nunchuck/nunchuck.h

@@ -0,0 +1,123 @@
+/*
+ * 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.
+ */
+#pragma once
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <upm.h>
+
+#include <mraa/i2c.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+    /**
+     * @file nunchuck.h
+     * @library nunchuck
+     * @brief C API for the nunchuck driver
+     *
+     * @include nunchuck.c
+     */
+
+    /**
+     * Device context
+     */
+    typedef struct _nunchuck_context {
+        mraa_i2c_context  i2c;
+
+        // sticks - x, y
+        int stickX;
+        int stickY;
+
+        // accel
+        int accelX;
+        int accelY;
+        int accelZ;
+
+        // buttons
+        bool buttonC;
+        bool buttonZ;
+
+    } *nunchuck_context;
+
+    /**
+     * NUNCHUCK constructor
+     *
+     * @param bus I2C bus to use
+     * @return A Device context, or NULL on error
+     */
+    nunchuck_context nunchuck_init(int bus);
+
+    /**
+     * Close the device and deallocate all resources.
+     *
+     * @param dev Device context
+     */
+    void nunchuck_close(nunchuck_context dev);
+
+    /**
+     * Reads and updates the current state of the controller.
+     *
+     * @param dev Device context
+     * @return UPM result
+     */
+    upm_result_t nunchuck_update(const nunchuck_context dev);
+
+    /**
+     * Returns the current analog stick X and Y positions.
+     * nunchuck_update() must have been called prior to calling this
+     * function.
+     *
+     * @param dev Device context
+     * @param x Pointer in which the X value will be stored
+     * @param y Pointer in which the Y value will be stored
+     */
+    void nunchuck_get_stick(const nunchuck_context dev, int *x, int *y);
+
+    /**
+     * Returns the current accelerometer values.  nunchuck_update()
+     * must have been called prior to calling this function.
+     *
+     * @param dev Device context
+     * @param x Pointer in which the X value will be stored
+     * @param y Pointer in which the Y value will be stored
+     * @param z Pointer in which the Z value will be stored
+     */
+    void nunchuck_get_acceleration(const nunchuck_context dev,
+                                   int *x, int *y, int *z);
+
+    /**
+     * Returns the current button values values.  nunchuck_update()
+     * must have been called prior to calling this function.
+     *
+     * @param dev Device context
+     * @param c Pointer in which the C button value will be stored
+     * @param z Pointer in which the Z button value will be stored
+     */
+    void nunchuck_get_buttons(const nunchuck_context dev, bool *c, bool *z);
+
+#ifdef __cplusplus
+}
+#endif