This source file includes following definitions.
- print_flags
- list_device
- print_usage
- main
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11 #include <unistd.h>
12 #include <stdlib.h>
13 #include <stdbool.h>
14 #include <stdio.h>
15 #include <dirent.h>
16 #include <errno.h>
17 #include <string.h>
18 #include <poll.h>
19 #include <fcntl.h>
20 #include <getopt.h>
21 #include <sys/ioctl.h>
22 #include <linux/gpio.h>
23
24 #include "gpio-utils.h"
25
26 struct gpio_flag {
27 char *name;
28 unsigned long mask;
29 };
30
31 struct gpio_flag flagnames[] = {
32 {
33 .name = "kernel",
34 .mask = GPIOLINE_FLAG_KERNEL,
35 },
36 {
37 .name = "output",
38 .mask = GPIOLINE_FLAG_IS_OUT,
39 },
40 {
41 .name = "active-low",
42 .mask = GPIOLINE_FLAG_ACTIVE_LOW,
43 },
44 {
45 .name = "open-drain",
46 .mask = GPIOLINE_FLAG_OPEN_DRAIN,
47 },
48 {
49 .name = "open-source",
50 .mask = GPIOLINE_FLAG_OPEN_SOURCE,
51 },
52 };
53
54 void print_flags(unsigned long flags)
55 {
56 int i;
57 int printed = 0;
58
59 for (i = 0; i < ARRAY_SIZE(flagnames); i++) {
60 if (flags & flagnames[i].mask) {
61 if (printed)
62 fprintf(stdout, " ");
63 fprintf(stdout, "%s", flagnames[i].name);
64 printed++;
65 }
66 }
67 }
68
69 int list_device(const char *device_name)
70 {
71 struct gpiochip_info cinfo;
72 char *chrdev_name;
73 int fd;
74 int ret;
75 int i;
76
77 ret = asprintf(&chrdev_name, "/dev/%s", device_name);
78 if (ret < 0)
79 return -ENOMEM;
80
81 fd = open(chrdev_name, 0);
82 if (fd == -1) {
83 ret = -errno;
84 fprintf(stderr, "Failed to open %s\n", chrdev_name);
85 goto exit_close_error;
86 }
87
88
89 ret = ioctl(fd, GPIO_GET_CHIPINFO_IOCTL, &cinfo);
90 if (ret == -1) {
91 ret = -errno;
92 perror("Failed to issue CHIPINFO IOCTL\n");
93 goto exit_close_error;
94 }
95 fprintf(stdout, "GPIO chip: %s, \"%s\", %u GPIO lines\n",
96 cinfo.name, cinfo.label, cinfo.lines);
97
98
99 for (i = 0; i < cinfo.lines; i++) {
100 struct gpioline_info linfo;
101
102 memset(&linfo, 0, sizeof(linfo));
103 linfo.line_offset = i;
104
105 ret = ioctl(fd, GPIO_GET_LINEINFO_IOCTL, &linfo);
106 if (ret == -1) {
107 ret = -errno;
108 perror("Failed to issue LINEINFO IOCTL\n");
109 goto exit_close_error;
110 }
111 fprintf(stdout, "\tline %2d:", linfo.line_offset);
112 if (linfo.name[0])
113 fprintf(stdout, " \"%s\"", linfo.name);
114 else
115 fprintf(stdout, " unnamed");
116 if (linfo.consumer[0])
117 fprintf(stdout, " \"%s\"", linfo.consumer);
118 else
119 fprintf(stdout, " unused");
120 if (linfo.flags) {
121 fprintf(stdout, " [");
122 print_flags(linfo.flags);
123 fprintf(stdout, "]");
124 }
125 fprintf(stdout, "\n");
126
127 }
128
129 exit_close_error:
130 if (close(fd) == -1)
131 perror("Failed to close GPIO character device file");
132 free(chrdev_name);
133 return ret;
134 }
135
136 void print_usage(void)
137 {
138 fprintf(stderr, "Usage: lsgpio [options]...\n"
139 "List GPIO chips, lines and states\n"
140 " -n <name> List GPIOs on a named device\n"
141 " -? This helptext\n"
142 );
143 }
144
145 int main(int argc, char **argv)
146 {
147 const char *device_name = NULL;
148 int ret;
149 int c;
150
151 while ((c = getopt(argc, argv, "n:")) != -1) {
152 switch (c) {
153 case 'n':
154 device_name = optarg;
155 break;
156 case '?':
157 print_usage();
158 return -1;
159 }
160 }
161
162 if (device_name)
163 ret = list_device(device_name);
164 else {
165 const struct dirent *ent;
166 DIR *dp;
167
168
169 dp = opendir("/dev");
170 if (!dp) {
171 ret = -errno;
172 goto error_out;
173 }
174
175 ret = -ENOENT;
176 while (ent = readdir(dp), ent) {
177 if (check_prefix(ent->d_name, "gpiochip")) {
178 ret = list_device(ent->d_name);
179 if (ret)
180 break;
181 }
182 }
183
184 ret = 0;
185 if (closedir(dp) == -1) {
186 perror("scanning devices: Failed to close directory");
187 ret = -errno;
188 }
189 }
190 error_out:
191 return ret;
192 }