Add LED status capability

Add the ability to return the status of the LEDs for CAPS_LOCK, NUM_LOCK and SCROLL_LOCK. Updates to Arduino-keyboard required for this to be useful.

Author: ScaredyCat

libraries/HID/src/HID.cpp

@@ -54,11 +54,11 @@ int HID_::getDescriptor(USBSetup& setup)
 			return -1;
 		total += res;
 	}
-	
+
 	// Reset the protocol on reenumeration. Normally the host should not assume the state of the protocol
 	// due to the USB specs, but Windows and Linux just assumes its in report mode.
 	protocol = HID_REPORT_PROTOCOL;
-	
+
 	return total;
 }
 
@@ -86,6 +86,11 @@ void HID_::AppendDescriptor(HIDSubDescriptor *node)
 	descriptorSize += node->length;
 }
 
+uint8_t HID_::getKeyboardLedsStatus(void)
+{
+	return _keyboardLedsStatus;
+}
+
 int HID_::SendReport(uint8_t id, const void* data, int len)
 {
 	auto ret = USB_Send(pluggedEndpoint, &id, 1);
@@ -133,6 +138,15 @@ bool HID_::setup(USBSetup& setup)
 		}
 		if (request == HID_SET_REPORT)
 		{
+			if (setup.wLength == 2)
+			{
+				uint8_t data[2];
+				if (2 == USB_RecvControl(data, 2))
+				{
+					_keyboardLedsStatus = data[1];
+					return true;
+				}
+			}
 			//uint8_t reportID = setup.wValueL;
 			//uint16_t length = setup.wLength;
 			//uint8_t data[length];

libraries/HID/src/HID.h

@@ -72,7 +72,7 @@ typedef struct
   uint8_t descLenH;
 } HIDDescDescriptor;
 
-typedef struct 
+typedef struct
 {
   InterfaceDescriptor hid;
   HIDDescDescriptor   desc;
@@ -95,6 +95,7 @@ class HID_ : public PluggableUSBModule
   int begin(void);
   int SendReport(uint8_t id, const void* data, int len);
   void AppendDescriptor(HIDSubDescriptor* node);
+  uint8_t getKeyboardLedsStatus(void);
 
 protected:
   // Implementation of the PluggableUSBModule
@@ -111,6 +112,7 @@ class HID_ : public PluggableUSBModule
 
   uint8_t protocol;
   uint8_t idle;
+  uint8_t _keyboardLedsStatus;
 };
 
 // Replacement for global singleton.