allow HID submodules to create runtime descriptors

with this PR you can add

\#include Keyboard.h
\#include Mouse.h
\#include HID.h

in the top of the sketch and you will expose a Mouse+Keyboard

From the library pow, simply add

static HID_Descriptor cb = {
	.length = sizeof(_hidReportDescriptor),
	.descriptor = _hidReportDescriptor,
};
static HIDDescriptorListNode node(&cb);
HID.AppendDescriptor(&node);

in the class' constructor and you are done!

Author: facchinm

Keyboard.cpp

@@ -21,33 +21,13 @@
 
 #if 1
 
-#include "HID.h"
 #include "Keyboard.h"
 
 //================================================================================
 //================================================================================
 //	Keyboard
 
-Keyboard_ Keyboard;
-
-Keyboard_::Keyboard_(void) 
-{
-}
-
-void Keyboard_::begin(void) 
-{
-}
-
-void Keyboard_::end(void) 
-{
-}
-
-void Keyboard_::sendReport(KeyReport* keys)
-{
-	HID.SendReport(2,keys,sizeof(KeyReport));
-}
-
-const u8 _hidReportDescriptor[] PROGMEM = {
+static const u8 _hidReportDescriptor[] PROGMEM = {
 
   //  Keyboard
     0x05, 0x01,                    // USAGE_PAGE (Generic Desktop)  // 47
@@ -80,6 +60,29 @@ const u8 _hidReportDescriptor[] PROGMEM = {
     0xc0,                          // END_COLLECTION
 };
 
+Keyboard_::Keyboard_(void) 
+{
+	static HID_Descriptor cb = {
+		.length = sizeof(_hidReportDescriptor),
+		.descriptor = _hidReportDescriptor,
+	};
+	static HIDDescriptorListNode node(&cb);
+	HID.AppendDescriptor(&node);
+}
+
+void Keyboard_::begin(void)
+{
+}
+
+void Keyboard_::end(void)
+{
+}
+
+void Keyboard_::sendReport(KeyReport* keys)
+{
+	HID.SendReport(2,keys,sizeof(KeyReport));
+}
+
 extern
 const uint8_t _asciimap[128] PROGMEM;
 
@@ -217,9 +220,6 @@ const uint8_t _asciimap[128] =
 	0				// DEL
 };
 
-size_t getsizeof_hidReportDescriptor() {
-	return sizeof(_hidReportDescriptor);
-}
 
 uint8_t USBPutChar(uint8_t c);
 

Keyboard.h

@@ -22,7 +22,7 @@
 #ifndef KEYBOARD_h
 #define KEYBOARD_h
 
-#if defined(_USING_HID)
+#if 0 //defined(_USING_HID)
 
 #error "Can only attach one submodule to HID module"
 
@@ -90,10 +90,10 @@ class Keyboard_ : public Print
   Keyboard_(void);
   void begin(void);
   void end(void);
-  virtual size_t write(uint8_t k);
-  virtual size_t press(uint8_t k);
-  virtual size_t release(uint8_t k);
-  virtual void releaseAll(void);
+  size_t write(uint8_t k);
+  size_t press(uint8_t k);
+  size_t release(uint8_t k);
+  void releaseAll(void);
 };
 extern Keyboard_ Keyboard;
 extern HID_ HID;