zephyr/drivers/input/linux_evdev_bottom.c

54 lines
998 B
C

/*
* Copyright 2023 Google LLC
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <errno.h>
#include <fcntl.h>
#include <linux/input.h>
#include <nsi_tracing.h>
#include <string.h>
#include <unistd.h>
#include "linux_evdev_bottom.h"
int linux_evdev_read(int fd, uint16_t *type, uint16_t *code, int32_t *value)
{
struct input_event ev;
int ret;
ret = read(fd, &ev, sizeof(ev));
if (ret < 0) {
if (errno == EAGAIN || errno == EINTR) {
return NATIVE_LINUX_EVDEV_NO_DATA;
}
nsi_print_warning("Read error: %s", strerror(errno));
return -EIO;
} else if (ret < sizeof(ev)) {
nsi_print_warning("Unexpected read size: %d, expecting %d",
ret, sizeof(ev));
return -EIO;
}
*type = ev.type;
*code = ev.code;
*value = ev.value;
return 0;
}
int linux_evdev_open(const char *path)
{
int fd;
fd = open(path, O_RDONLY | O_NONBLOCK);
if (fd < 0) {
nsi_print_error_and_exit(
"Failed to open the evdev device %s: %s\n",
path, strerror(errno));
}
return fd;
}