Massdrop keyboard support (#3780)

* Massdrop SAMD51

Massdrop SAMD51 keyboards initial project upload

* Removing relocated files

Removing files that were relocated and not deleted from previous location

* LED queue fix and cleaning

Cleaned some white space or comments.
Fix for LED I2C command queue.
Cleaned up interrupts.
Added debug function for printing numbers to scope through m15 line.

* Factory programmed serial usage

Ability to use factory programmed serial in hub and keyboard usb descriptors

* USB serial number and bugfix

Added support for factory programmed serial and usage.
Incorporated bootloader's conditional compiling to align project closer.
Fixed issue when USB device attempted to send before enabled.
General white space and comment cleanup.

* Project cleanup

Cleaned up project in terms of white space, commented code, and unecessary files.
NKRO keyboard is now using correct setreport although KBD was fine to use.
Fixed broken linkage to __xprintf for serial debug statements.

* Fix for extra keys

Fixed possible USB hang on extra keys report set missing

* I2C cleanup

I2C cleanup and file renames necessary for master branch merge

* Boot tracing and clocks cleanup

Added optional boot debug trace mode through debug LED codes.
General clock code cleanup.

* Relocate ARM/Atmel headers

Moved ARM/Atmel header folder from drivers to lib and made necessary makefile changes.

* Pull request changes

Pull request changes

* Keymap and compile flag fix

Keymap fix for momentary layer.
Potential compile flag fix for Travis CI failure.

* va_list include fix

Fix for va_list compile failure

* Include file case fixes

Fixes for include files with incorrect case

* ctrl and alt67 keyboard readme

Added ctrl and alt67 keyboard readme files

1 files changed, 97 insertions, 0 deletions

diff --git a/tmk_core/protocol/arm_atsam/usb/usb_main.h b/tmk_core/protocol/arm_atsam/usb/usb_main.h
new file mode 100644
index 000000000..b7adaa1a7
--- /dev/null
+++ b/tmk_core/protocol/arm_atsam/usb/usb_main.h
@@ -0,0 +1,97 @@
+/**
+ * \file
+ *
+ * \brief Declaration of main function used by HID keyboard example
+ *
+ * Copyright (c) 2009-2015 Atmel Corporation. All rights reserved.
+ *
+ * \asf_license_start
+ *
+ * \page License
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * 3. The name of Atmel may not be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * 4. This software may only be redistributed and used in connection with an
+ *    Atmel microcontroller product.
+ *
+ * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
+ * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
+ * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * \asf_license_stop
+ *
+ */
+/*
+ * Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a>
+ */
+
+#ifndef _MAIN_H_
+#define _MAIN_H_
+
+//Enters the application in low power mode
+//Callback called when USB host sets USB line in suspend state
+void main_suspend_action(void);
+
+//Called by UDD when the USB line exit of suspend state
+void main_resume_action(void);
+
+//Called when a start of frame is received on USB line
+void main_sof_action(void);
+
+//Called by UDC when USB Host request to enable remote wakeup
+void main_remotewakeup_enable(void);
+
+//Called by UDC when USB Host request to disable remote wakeup
+void main_remotewakeup_disable(void);
+
+
+#ifdef KBD
+extern volatile bool main_b_kbd_enable;
+bool main_kbd_enable(void);
+void main_kbd_disable(void);
+#endif //KBD
+
+#ifdef NKRO
+extern volatile bool main_b_nkro_enable;
+bool main_nkro_enable(void);
+void main_nkro_disable(void);
+#endif //NKRO
+
+#ifdef EXK
+extern volatile bool main_b_exk_enable;
+bool main_exk_enable(void);
+void main_exk_disable(void);
+#endif //EXK
+
+#ifdef MOU
+extern volatile bool main_b_mou_enable;
+bool main_mou_enable(void);
+void main_mou_disable(void);
+#endif //MOU
+
+#ifdef RAW
+extern volatile bool main_b_raw_enable;
+bool main_raw_enable(void);
+void main_raw_disable(void);
+#endif //RAW
+
+#endif // _MAIN_H_