53 lines
1.5 KiB
C
53 lines
1.5 KiB
C
|
/*
|
||
|
|
* PD Buddy Firmware Library - USB Power Delivery for everyone
|
||
|
|
* Copyright 2017-2018 Clayton G. Hobbs
|
||
|
|
*
|
||
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
|
* you may not use this file except in compliance with the License.
|
||
|
|
* You may obtain a copy of the License at
|
||
|
|
*
|
||
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
*
|
||
|
|
* Unless required by applicable law or agreed to in writing, software
|
||
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
|
* See the License for the specific language governing permissions and
|
||
|
|
* limitations under the License.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef PDB_MSG_H
|
||
|
|
#define PDB_MSG_H
|
||
|
|
|
||
|
|
#include <stdint.h>
|
||
|
|
|
||
|
|
/*
|
||
|
|
* PD message union
|
||
|
|
*
|
||
|
|
* This can be safely read from or written to in any form without any
|
||
|
|
* transformations because everything in the system is little-endian.
|
||
|
|
*
|
||
|
|
* Two bytes of padding are required at the start to prevent problems due to
|
||
|
|
* alignment. Specifically, without the padding, &obj[0] != &bytes[2], making
|
||
|
|
* the statement in the previous paragraph invalid.
|
||
|
|
*/
|
||
|
|
union pd_msg {
|
||
|
|
struct {
|
||
|
|
uint8_t _pad1[2];
|
||
|
|
uint8_t bytes[30];
|
||
|
|
} __attribute__((packed));
|
||
|
|
struct {
|
||
|
|
uint8_t _pad2[2];
|
||
|
|
uint16_t hdr;
|
||
|
|
union {
|
||
|
|
uint32_t obj[7];
|
||
|
|
struct {
|
||
|
|
uint16_t exthdr;
|
||
|
|
uint8_t data[26];
|
||
|
|
};
|
||
|
|
};
|
||
|
|
} __attribute__((packed));
|
||
|
|
};
|
||
|
|
|
||
|
|
|
||
|
|
#endif /* PDB_MSG_H */
|