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Commit | Line | Data |
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2a144dd0 LW |
1 | /* |
2 | * gpio-hammer - example swiss army knife to shake GPIO lines on a system | |
3 | * | |
4 | * Copyright (C) 2016 Linus Walleij | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms of the GNU General Public License version 2 as published by | |
8 | * the Free Software Foundation. | |
9 | * | |
10 | * Usage: | |
11 | * gpio-hammer -n <device-name> -o <offset1> -o <offset2> | |
12 | */ | |
13 | ||
14 | #include <unistd.h> | |
15 | #include <stdlib.h> | |
16 | #include <stdbool.h> | |
17 | #include <stdio.h> | |
18 | #include <dirent.h> | |
19 | #include <errno.h> | |
20 | #include <string.h> | |
21 | #include <poll.h> | |
22 | #include <fcntl.h> | |
23 | #include <getopt.h> | |
24 | #include <sys/ioctl.h> | |
25 | #include <linux/gpio.h> | |
74100bb9 | 26 | #include "gpio-utils.h" |
2a144dd0 LW |
27 | |
28 | int hammer_device(const char *device_name, unsigned int *lines, int nlines, | |
29 | unsigned int loops) | |
30 | { | |
2a144dd0 | 31 | struct gpiohandle_data data; |
2a144dd0 LW |
32 | char swirr[] = "-\\|/"; |
33 | int fd; | |
34 | int ret; | |
35 | int i, j; | |
36 | unsigned int iteration = 0; | |
37 | ||
74100bb9 BJZ |
38 | memset(&data.values, 0, sizeof(data.values)); |
39 | ret = gpiotools_request_linehandle(device_name, lines, nlines, | |
40 | GPIOHANDLE_REQUEST_OUTPUT, &data, | |
41 | "gpio-hammler"); | |
2a144dd0 | 42 | if (ret < 0) |
74100bb9 BJZ |
43 | goto exit_error; |
44 | else | |
45 | fd = ret; | |
2a144dd0 | 46 | |
74100bb9 BJZ |
47 | ret = gpiotools_get_values(fd, &data); |
48 | if (ret < 0) | |
2a144dd0 | 49 | goto exit_close_error; |
2a144dd0 | 50 | |
2a144dd0 LW |
51 | fprintf(stdout, "Hammer lines ["); |
52 | for (i = 0; i < nlines; i++) { | |
53 | fprintf(stdout, "%d", lines[i]); | |
54 | if (i != (nlines - 1)) | |
55 | fprintf(stdout, ", "); | |
56 | } | |
57 | fprintf(stdout, "] on %s, initial states: [", device_name); | |
58 | for (i = 0; i < nlines; i++) { | |
59 | fprintf(stdout, "%d", data.values[i]); | |
60 | if (i != (nlines - 1)) | |
61 | fprintf(stdout, ", "); | |
62 | } | |
63 | fprintf(stdout, "]\n"); | |
64 | ||
65 | /* Hammertime! */ | |
66 | j = 0; | |
67 | while (1) { | |
68 | /* Invert all lines so we blink */ | |
69 | for (i = 0; i < nlines; i++) | |
70 | data.values[i] = !data.values[i]; | |
71 | ||
74100bb9 BJZ |
72 | ret = gpiotools_set_values(fd, &data); |
73 | if (ret < 0) | |
2a144dd0 | 74 | goto exit_close_error; |
74100bb9 | 75 | |
2a144dd0 | 76 | /* Re-read values to get status */ |
74100bb9 BJZ |
77 | ret = gpiotools_get_values(fd, &data); |
78 | if (ret < 0) | |
2a144dd0 | 79 | goto exit_close_error; |
2a144dd0 LW |
80 | |
81 | fprintf(stdout, "[%c] ", swirr[j]); | |
82 | j++; | |
83 | if (j == sizeof(swirr)-1) | |
84 | j = 0; | |
85 | ||
86 | fprintf(stdout, "["); | |
87 | for (i = 0; i < nlines; i++) { | |
88 | fprintf(stdout, "%d: %d", lines[i], data.values[i]); | |
89 | if (i != (nlines - 1)) | |
90 | fprintf(stdout, ", "); | |
91 | } | |
92 | fprintf(stdout, "]\r"); | |
93 | fflush(stdout); | |
94 | sleep(1); | |
95 | iteration++; | |
96 | if (loops && iteration == loops) | |
97 | break; | |
98 | } | |
99 | fprintf(stdout, "\n"); | |
100 | ret = 0; | |
101 | ||
102 | exit_close_error: | |
74100bb9 BJZ |
103 | gpiotools_release_linehandle(fd); |
104 | exit_error: | |
2a144dd0 LW |
105 | return ret; |
106 | } | |
107 | ||
108 | void print_usage(void) | |
109 | { | |
110 | fprintf(stderr, "Usage: gpio-hammer [options]...\n" | |
111 | "Hammer GPIO lines, 0->1->0->1...\n" | |
112 | " -n <name> Hammer GPIOs on a named device (must be stated)\n" | |
113 | " -o <n> Offset[s] to hammer, at least one, several can be stated\n" | |
114 | " [-c <n>] Do <n> loops (optional, infinite loop if not stated)\n" | |
115 | " -? This helptext\n" | |
116 | "\n" | |
117 | "Example:\n" | |
118 | "gpio-hammer -n gpiochip0 -o 4\n" | |
119 | ); | |
120 | } | |
121 | ||
122 | int main(int argc, char **argv) | |
123 | { | |
124 | const char *device_name = NULL; | |
125 | unsigned int lines[GPIOHANDLES_MAX]; | |
126 | unsigned int loops = 0; | |
127 | int nlines; | |
128 | int c; | |
129 | int i; | |
130 | ||
131 | i = 0; | |
132 | while ((c = getopt(argc, argv, "c:n:o:?")) != -1) { | |
133 | switch (c) { | |
134 | case 'c': | |
135 | loops = strtoul(optarg, NULL, 10); | |
136 | break; | |
137 | case 'n': | |
138 | device_name = optarg; | |
139 | break; | |
140 | case 'o': | |
141 | lines[i] = strtoul(optarg, NULL, 10); | |
142 | i++; | |
143 | break; | |
144 | case '?': | |
145 | print_usage(); | |
146 | return -1; | |
147 | } | |
148 | } | |
149 | nlines = i; | |
150 | ||
151 | if (!device_name || !nlines) { | |
152 | print_usage(); | |
153 | return -1; | |
154 | } | |
155 | return hammer_device(device_name, lines, nlines, loops); | |
156 | } |