Added interface iButton

Signed-off-by: Stefan Andritoiu <stefan.andritoiu@gmail.com>

include/interfaces/iButton.hpp

@@ -0,0 +1,44 @@
+/*
+ * Author: Mihai Stefanescu <mihai.stefanescu@rinftech.com>
+ * Copyright (c) 2018 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
+
+namespace upm
+{
+/**
+ * @brief Interface for Button sensors
+*/
+  class iButton
+  {
+  public:
+    virtual ~iButton() {}
+
+    /**
+     * Gets the current button press state.
+     *
+     * @returns Button state
+     */
+    virtual bool isPressed() = 0;
+  };
+}

src/button/button.cxx

@@ -59,6 +59,11 @@ int Button::value()
     return mraa_gpio_read(m_gpio);
 }
 
+bool Button::isPressed()
+{
+    return (bool) Button::value();
+}
+
 void Button::installISR(mraa::Edge level, void (*isr)(void *), void *arg)
 {
   if (m_isrInstalled)

src/button/button.hpp

@@ -28,6 +28,7 @@
 
 #include <string>
 #include <mraa/gpio.hpp>
+#include <interfaces/iButton.hpp>
 
 namespace upm {
 
@@ -54,7 +55,7 @@ namespace upm {
  * @image html button.jpg
  * @snippet button.cxx Interesting
  */
-class Button{
+class Button : virtual public iButton {
     public:
         /**
          * button constructor
@@ -79,6 +80,13 @@ class Button{
          */
         int value();
 
+        /**
+         * Gets the current button press state.
+         *
+         * @returns Button state
+         */
+         virtual bool isPressed();
+
         /**
          * Installs an interrupt service routine (ISR) to be called when
          * the button is activated or deactivated.

src/grove/grovebutton.cxx

@@ -58,6 +58,11 @@ int GroveButton::value()
     return mraa_gpio_read(m_gpio);
 }
 
+bool GroveButton::isPressed()
+{
+    return (bool) GroveButton::value();
+}
+
 void GroveButton::installISR(mraa::Edge level, void (*isr)(void *), void *arg)
 {
   if (m_isrInstalled)

src/grove/grovebutton.hpp

@@ -29,6 +29,7 @@
 #include <string>
 #include <mraa/gpio.hpp>
 #include "grovebase.hpp"
+#include <interfaces/iButton.hpp>
 
 namespace upm {
 
@@ -51,7 +52,7 @@ namespace upm {
  * @image html grovebutton.jpg
  * @snippet grove-grovebutton.cxx Interesting
  */
-class GroveButton: public Grove {
+class GroveButton: public Grove, virtual public iButton {
     public:
         /**
          * Grove button constructor
@@ -76,6 +77,13 @@ class GroveButton: public Grove {
          */
         int value();
 
+        /**
+         * Gets the current button press state.
+         *
+         * @returns Button state
+         */
+         virtual bool isPressed();
+
         /**
          * Installs an interrupt service routine (ISR) to be called when
          * the button is activated or deactivated.

src/ttp223/ttp223.hpp

@@ -25,6 +25,7 @@
 
 #include <string>
 #include <mraa/gpio.hpp>
+#include <interfaces/iButton.hpp>
 
 namespace upm {
 /**
@@ -52,7 +53,7 @@ namespace upm {
  * @image html ttp223.jpg
  * @snippet ttp223.cxx Interesting
  */
-class TTP223 {
+class TTP223 : virtual public iButton {
     public:
         /**
          * TTP223 constructor
@@ -85,7 +86,7 @@ class TTP223 {
          *
          * @return True if touched, false otherwise
          */
-        bool isPressed();
+        virtual bool isPressed();
 
         /**
          * Installs an interrupt service routine (ISR) to be called when