master-thesis/gm_platform/fw/serial.h
2020-01-27 21:58:22 +01:00

72 lines
2.1 KiB
C

/*
* This file is part of the libusbhost library
* hosted at http://github.com/libusbhost/libusbhost
*
* Copyright (C) 2015 Amir Hammad <amir.hammad@hotmail.com>
*
*
* libusbhost is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This library 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef __SERIAL_H__
#define __SERIAL_H__
#include <stdint.h>
#include <stdarg.h>
#include <errno.h>
#include "global.h"
struct dma_tx_buf {
/* The following fields are accessed only from DMA ISR */
ssize_t xfr_start; /* Start index of running DMA transfer */
ssize_t xfr_end; /* End index of running DMA transfer plus one */
uint8_t cur_packet;
/* The following fields are written only from non-interrupt code */
ssize_t wr_pos; /* Next index to be written */
ssize_t packet_start[8];
/* The following may be accessed by anything */
uint8_t data[512];
};
struct __attribute__((__packed__)) ll_pkt {
uint32_t crc32;
/* CRC computed over entire packet starting here */
uint8_t pid;
uint8_t _pad;
uint8_t data[];
};
enum ctrl_pkt_type {
CTRL_PKT_RESET = 1,
CTRL_PKT_ACK = 2,
CTRL_PKT_RETRANSMIT = 3,
};
struct __attribute__((__packed__)) ctrl_pkt {
uint8_t type;
uint8_t orig_id;
};
extern volatile struct dma_tx_buf usart_tx_buf;
void usart_dma_init(void);
int usart_dma_fifo_push(volatile struct dma_tx_buf *buf, uint8_t c);
int usart_send_packet_nonblocking(struct ll_pkt *pkt, size_t pkt_len);
int usart_ack_packet(uint8_t idx);
#endif // __SERIAL_H__