Adding McHCK DFU Bootloader

- Heavily modified, not compatible with McHCK images
- Uses 4k of Flash (rather than 3k)
- LED turns on when in firmware flash mode
- Changed the USB IDs
- Added CMake build system
- Updated linker script to be closer to what is used for the rest of the projects
- Removed a lot of unnecessary code
- Added a license header to each file (using the same license as the McHCK had)
- Updated the USB Vendor, Product and Serial strings
- Using the Kiibohd initialization sequence rather than the McHCK one
- Using Kiibohd interrupt vector table and other misc mk20dx setup

Bootloader/usb-internal.h

@@ -0,0 +1,104 @@
+/* Copyright (c) 2011,2012 Simon Schubert <2@0x2c.org>.
+ * Modifications by Jacob Alexander 2014 <haata@kiibohd.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __USB_INTERNAL_H
+#define __USB_INTERNAL_H
+
+/**
+ * Internal driver structures
+ */
+
+/**
+ * USB state machine
+ * =================
+ *
+ * Device configuration states:
+ *
+ * Attached <-> Powered
+ * Powered -(reset)-> Default
+ * Default -(SET_ADDRESS)-> Address
+ * Address -(SET_CONFIGURATION)-> Configured
+ * Configured -(SET_CONFIGURATION 0)-> Address
+ * Address -(SET_ADDRESS 0)-> Default
+ * [Default, Configured, Address] -(reset)-> Default
+ */
+
+// ----- Defines -----
+
+#ifndef USB_MAX_EP
+#define USB_MAX_EP 16
+#endif
+
+
+
+// ----- Structs -----
+
+struct usbd_ep_pipe_state_t {
+	enum usb_ep_pingpong pingpong; /* next desc to use */
+	enum usb_data01 data01;
+	size_t transfer_size;
+	size_t pos;
+	uint8_t *data_buf;
+	const uint8_t *copy_source;
+	int short_transfer;
+	ep_callback_t callback;
+	void *callback_data;
+	size_t ep_maxsize;
+	/* constant */
+	int ep_num;
+	enum usb_ep_dir ep_dir;
+};
+
+struct usbd_ep_state_t {
+	union {
+		struct usbd_ep_pipe_state_t pipe[2];
+		struct {
+			struct usbd_ep_pipe_state_t rx;
+			struct usbd_ep_pipe_state_t tx;
+		};
+	};
+};
+
+struct usbd_t {
+	struct usbd_function_ctx_header functions;
+	struct usbd_function control_function;
+	const struct usbd_device *identity;
+	int address;
+	int config;
+	enum usbd_dev_state {
+		USBD_STATE_DISABLED = 0,
+		USBD_STATE_DEFAULT,
+		USBD_STATE_SETTING_ADDRESS,
+		USBD_STATE_ADDRESS,
+		USBD_STATE_CONFIGURED
+	} state;
+	enum usb_ctrl_req_dir ctrl_dir;
+	struct usbd_ep_state_t ep_state[USB_MAX_EP];
+};
+
+extern struct usbd_t usb;
+
+
+
+// ----- Functions -----
+
+void usb_restart(void);
+void usb_enable(void);
+const struct usbd_config *usb_get_config_data(int config);
+
+#endif
+