usb_dev.c

/* Teensyduino Core Library
 * http://www.pjrc.com/teensy/
 * Copyright (c) 2013 PJRC.COM, LLC.
 *
 * 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:
 *
 * 1. The above copyright notice and this permission notice shall be 
 * included in all copies or substantial portions of the Software.
 *
 * 2. If the Software is incorporated into a build system that allows 
 * selection among a list of target devices, then similar target
 * devices manufactured by PJRC.COM must be included in the list of
 * target devices and selectable in the same manner.
 *
 * 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.
 */

#include "mk20dx128.h"
#include "usb_dev.h"
#include "usb_mem.h"

// buffer descriptor table

typedef struct {
	uint32_t desc;
	void * addr;
} bdt_t;

__attribute__ ((section(".usbdescriptortable"), used))
static bdt_t table[(NUM_ENDPOINTS+1)*4];

static usb_packet_t *rx_first[NUM_ENDPOINTS];
static usb_packet_t *rx_last[NUM_ENDPOINTS];
static usb_packet_t *tx_first[NUM_ENDPOINTS];
static usb_packet_t *tx_last[NUM_ENDPOINTS];
uint16_t usb_rx_byte_count_data[NUM_ENDPOINTS];

static uint8_t tx_state[NUM_ENDPOINTS];
#define TX_STATE_BOTH_FREE_EVEN_FIRST	0
#define TX_STATE_BOTH_FREE_ODD_FIRST	1
#define TX_STATE_EVEN_FREE		2
#define TX_STATE_ODD_FREE		3
#define TX_STATE_NONE_FREE_EVEN_FIRST	4
#define TX_STATE_NONE_FREE_ODD_FIRST	5

#define BDT_OWN		0x80
#define BDT_DATA1	0x40
#define BDT_DATA0	0x00
#define BDT_DTS		0x08
#define BDT_STALL	0x04
#define BDT_PID(n)	(((n) >> 2) & 15)

#define BDT_DESC(count, data)	(BDT_OWN | BDT_DTS \
				| ((data) ? BDT_DATA1 : BDT_DATA0) \
				| ((count) << 16))

#define TX   1