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
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* gpio-hammer - example swiss army knife to shake GPIO lines on a system
*
* Copyright (C) 2016 Linus Walleij
*
* Usage:
* gpio-hammer -n <device-name> -o <offset1> -o <offset2>
*/
#include <unistd.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdio.h>
#include <dirent.h>
#include <errno.h>
#include <string.h>
#include <poll.h>
#include <fcntl.h>
#include <getopt.h>
#include <sys/ioctl.h>
#include <linux/gpio.h>
#include "gpio-utils.h"
int hammer_device(const char *device_name, unsigned int *lines, int nlines,
unsigned int loops)
{
struct gpiohandle_data data;
char swirr[] = "-\\|/";
int fd;
int ret;
int i, j;
unsigned int iteration = 0;
memset(&data.values, 0, sizeof(data.values));
ret = gpiotools_request_linehandle(device_name, lines, nlines,
GPIOHANDLE_REQUEST_OUTPUT, &data,
"gpio-hammer");
if (ret < 0)
goto exit_error;
else
fd = ret;
ret = gpiotools_get_values(fd, &data);
if (ret < 0)
goto exit_close_error;
fprintf(stdout, "Hammer lines [");
for (i = 0; i < nlines; i++) {
fprintf(stdout, "%d", lines[i]);
if (i != (nlines - 1))
fprintf(stdout, ", ");
}
fprintf(stdout, "] on %s, initial states: [", device_name);
for (i = 0; i < nlines; i++) {
fprintf(stdout, "%d", data.values[i]);
if (i != (nlines - 1))
fprintf(stdout, ", ");
}
fprintf(stdout, "]\n");
/* Hammertime! */
j = 0;
while (1) {
/* Invert all lines so we blink */
for (i = 0; i < nlines; i++)
data.values[i] = !data.values[i];
ret = gpiotools_set_values(fd, &data);
if (ret < 0)
goto exit_close_error;
/* Re-read values to get status */
ret = gpiotools_get_values(fd, &data);
if (ret < 0)
goto exit_close_error;
fprintf(stdout, "[%c] ", swirr[j]);
j++;
if (j == sizeof(swirr) - 1)
j = 0;
fprintf(stdout, "[");
for (i = 0; i < nlines; i++) {
fprintf(stdout, "%d: %d", lines[i], data.values[i]);
if (i != (nlines - 1))
fprintf(stdout, ", ");
}
fprintf(stdout, "]\r");
fflush(stdout);
sleep(1);
iteration++;
if (loops && iteration == loops)
break;
}
fprintf(stdout, "\n");
ret = 0;
exit_close_error:
gpiotools_release_linehandle(fd);
exit_error:
return ret;
}
void print_usage(void)
{
fprintf(stderr, "Usage: gpio-hammer [options]...\n"
"Hammer GPIO lines, 0->1->0->1...\n"
" -n <name> Hammer GPIOs on a named device (must be stated)\n"
" -o <n> Offset[s] to hammer, at least one, several can be stated\n"
" [-c <n>] Do <n> loops (optional, infinite loop if not stated)\n"
" -? This helptext\n"
"\n"
"Example:\n"
"gpio-hammer -n gpiochip0 -o 4\n"
);
}
int main(int argc, char **argv)
{
const char *device_name = NULL;
unsigned int lines[GPIOHANDLES_MAX];
unsigned int loops = 0;
int nlines;
int c;
int i;
i = 0;
while ((c = getopt(argc, argv, "c:n:o:?")) != -1) {
switch (c) {
case 'c':
loops = strtoul(optarg, NULL, 10);
break;
case 'n':
device_name = optarg;
break;
case 'o':
/*
* Avoid overflow. Do not immediately error, we want to
* be able to accurately report on the amount of times
* '-o' was given to give an accurate error message
*/
if (i < GPIOHANDLES_MAX)
lines[i] = strtoul(optarg, NULL, 10);
i++;
break;
case '?':
print_usage();
return -1;
}
}
if (i >= GPIOHANDLES_MAX) {
fprintf(stderr,
"Only %d occurrences of '-o' are allowed, %d were found\n",
GPIOHANDLES_MAX, i + 1);
return -1;
}
nlines = i;
if (!device_name || !nlines) {
print_usage();
return -1;
}
return hammer_device(device_name, lines, nlines, loops);
}
|
