circuitpython/atmel-samd/asf4/samd51/usb/usb_protocol.c

147 lines
4.1 KiB
C

/**
* \file
*
* \brief USB protocol implementation.
*
* This file contains the USB definitions and data structures provided by the
* USB 2.0 specification.
*
* Copyright (C) 2015 Atmel Corporation. All rights reserved.
*
* \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 AVR 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.
*/
#define CONF_NO_ASSERT_CHECK
#include "usb_protocol.h"
#ifdef CONF_NO_ASSERT_CHECK
#define _param_error_check(cond)
#define _desc_len_check() \
if (usb_desc_len(desc) < 2) { \
/* Encounter an invalid descriptor. */ \
return NULL; \
}
#else
#define _param_error_check(cond) ASSERT(cond)
#define _desc_len_check() ASSERT(usb_desc_len(desc) >= 2)
#endif
uint8_t *usb_find_desc(uint8_t *desc, uint8_t *eof, uint8_t type)
{
_param_error_check(desc && eof && (desc < eof));
while (desc < eof) {
_desc_len_check();
if (type == usb_desc_type(desc)) {
return desc;
}
desc = usb_desc_next(desc);
}
return NULL;
}
uint8_t *usb_find_iface_after(uint8_t *desc, uint8_t *eof, uint8_t iface_n)
{
_param_error_check(desc && eof && (desc < eof));
while (desc < eof) {
_desc_len_check();
if (USB_DT_INTERFACE == usb_desc_type(desc)) {
if (iface_n != desc[2]) {
return desc;
}
}
desc = usb_desc_next(desc);
}
return eof;
}
uint8_t *usb_find_ep_desc(uint8_t *desc, uint8_t *eof)
{
_param_error_check(desc && eof && (desc < eof));
while (desc < eof) {
_desc_len_check();
if (USB_DT_INTERFACE == usb_desc_type(desc)) {
break;
}
if (USB_DT_ENDPOINT == usb_desc_type(desc)) {
return desc;
}
desc = usb_desc_next(desc);
}
return NULL;
}
uint8_t *usb_find_cfg_desc(uint8_t *desc, uint8_t *eof, uint8_t cfg_value)
{
_param_error_check(desc && eof && (desc < eof));
desc = usb_find_desc(desc, eof, USB_DT_CONFIG);
if (!desc) {
return NULL;
}
while (desc < eof) {
_desc_len_check();
if (desc[1] != USB_DT_CONFIG) {
break;
}
if (desc[5] == cfg_value) {
return desc;
}
desc = usb_cfg_desc_next(desc);
}
return NULL;
}
uint8_t *usb_find_str_desc(uint8_t *desc, uint8_t *eof, uint8_t str_index)
{
uint8_t i;
_param_error_check(desc && eof && (desc < eof));
for (i = 0; desc < eof;) {
desc = usb_find_desc(desc, eof, USB_DT_STRING);
if (desc) {
_desc_len_check();
if (i == str_index) {
return desc;
}
i++;
desc = usb_desc_next(desc);
} else {
return NULL;
}
}
return NULL;
}