zephyr/drivers/can/can_native_linux_adapt.c

154 lines
3.1 KiB
C

/*
* Copyright (c) 2019 Intel Corporation
* Copyright (c) 2022 Martin Jäger <martin@libre.solar>
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
*
* Routines setting up the host system. Those are placed in separate file
* because there is naming conflicts between host and zephyr network stacks.
*/
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <errno.h>
#include <string.h>
#include <stdbool.h>
/* Linux host include files. */
#ifdef __linux
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <sys/select.h>
#include <net/if.h>
#include <linux/if.h>
#include <linux/can.h>
#include <linux/can/raw.h>
#else
#error "This driver can only be built on Linux systems"
#endif
#include "can_native_linux_adapt.h"
#ifndef CANFD_FDF
/* Linux kernels before v5.14 do not define CANFD_FDF */
#define CANFD_FDF 0x04
#endif /* CANFD_FDF */
int linux_socketcan_iface_open(const char *if_name)
{
struct sockaddr_can addr;
struct ifreq ifr;
int fd, opt, ret = -EINVAL;
fd = socket(PF_CAN, SOCK_RAW, CAN_RAW);
if (fd < 0) {
return -errno;
}
(void)memset(&ifr, 0, sizeof(ifr));
(void)memset(&addr, 0, sizeof(addr));
strncpy(ifr.ifr_name, if_name, IFNAMSIZ - 1);
ret = ioctl(fd, SIOCGIFINDEX, (void *)&ifr);
if (ret < 0) {
close(fd);
return -errno;
}
addr.can_ifindex = ifr.ifr_ifindex;
addr.can_family = PF_CAN;
ret = bind(fd, (struct sockaddr *)&addr, sizeof(addr));
if (ret < 0) {
close(fd);
return -errno;
}
/* this option must always be enabled in order to receive TX confirmations */
opt = 1;
ret = setsockopt(fd, SOL_CAN_RAW, CAN_RAW_RECV_OWN_MSGS, &opt, sizeof(opt));
if (ret < 0) {
close(fd);
return -errno;
}
return fd;
}
int linux_socketcan_iface_close(int fd)
{
return close(fd);
}
int linux_socketcan_poll_data(int fd)
{
struct timeval timeout;
fd_set rset;
int ret;
FD_ZERO(&rset);
FD_SET(fd, &rset);
timeout.tv_sec = 0;
timeout.tv_usec = 0;
ret = select(fd + 1, &rset, NULL, NULL, &timeout);
if (ret < 0 && errno != EINTR) {
return -errno;
} else if (ret > 0) {
if (FD_ISSET(fd, &rset)) {
return 0;
}
}
return -EAGAIN;
}
int linux_socketcan_read_data(int fd, void *buf, size_t buf_len, bool *msg_confirm)
{
struct canfd_frame *frame = (struct canfd_frame *)buf;
struct msghdr msg = {0};
struct iovec iov = {
.iov_base = buf,
.iov_len = buf_len,
};
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
int ret = (int)recvmsg(fd, &msg, MSG_WAITALL);
if (msg_confirm != NULL) {
*msg_confirm = (msg.msg_flags & MSG_CONFIRM) != 0;
}
/* Make sure to set the flags for all frames received via the Linux API.
*
* Zephyr relies on defined flags field of the SocketCAN data for both FD and classical CAN
* frames. In Linux the flags field is undefined for legacy frames.
*/
if (ret == CANFD_MTU) {
frame->flags |= CANFD_FDF;
} else if (ret == CAN_MTU) {
frame->flags = 0;
}
return ret;
}
int linux_socketcan_set_mode_fd(int fd, bool mode_fd)
{
int opt = mode_fd ? 1 : 0;
return setsockopt(fd, SOL_CAN_RAW, CAN_RAW_FD_FRAMES, &opt, sizeof(opt));
}