1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
/*
* Copyright (C) 2015 The Android Open Source Project
*
* 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.
*/
#include "sync_clock.h"
#include <errno.h>
#include <fcntl.h>
#include <linux/usbdevice_fs.h>
#include <stdio.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <unistd.h>
int main(int argc, char ** argv) {
if(argc < 2) {
printf("Usage %s <device_path>\n"
"Try `lsusb | grep eensy` and use /dev/bus/usb/<Bus>/<Device>\n",
argv[0]);
return 1;
}
printf("Opening %s\n", argv[1]);
int fd = open(argv[1], O_RDWR);
printf("open() fd=%d, errno=%d, %s\n", fd, errno, strerror(errno));
// The interface and endpoint numbers are defined by the TeensyUSB. They may
// be different depending on the mode (Serial vs HID) the Teensy code is
// compiled in. A real app would employ some discovery logic here. To list
// the interfaces and endpoints use `lsusb --verbose` or an app like USB
// Host Viewer on Android. Look for a "CDC Data" interface (class 0x0a).
int interface = 1;
int ep_out = 0x03;
int ep_in = 0x84;
int ret = ioctl(fd, USBDEVFS_CLAIMINTERFACE, &interface);
printf("Interface claimed retval=%d, errno=%d, %s\n", ret, errno, strerror(errno));
if (errno == EBUSY) {
printf("You may need to run 'sudo rmmod cdc_acm' to release the "
"interface claimed by the kernel serial driver.");
return 1;
}
struct clock_connection clk;
clk.fd = fd;
clk.endpoint_in = ep_in;
clk.endpoint_out = ep_out;
sync_clocks(&clk);
printf("===========================\n"
"sync_clocks base_t=%lld, minE=%d, maxE=%d\n",
(long long int)clk.t_base, clk.minE, clk.maxE);
// Check for clock drift. Try sleeping here to let it actually drift away.
update_bounds(&clk);
printf("*** UPDATE ****************\n"
"Update_bounds base_t=%lld, minE=%d, maxE=%d\n",
(long long int)(clk.t_base), clk.minE, clk.maxE
);
close(fd);
return 0;
}
|
