Commit | Line | Data |
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35647167 FT |
1 | #include <unistd.h> |
2 | #include <stdlib.h> | |
3 | #include <stdio.h> | |
4 | #include <string.h> | |
5 | #include <fcntl.h> | |
6 | #include <errno.h> | |
7 | #include <err.h> | |
8 | ||
cc450aa9 FT |
9 | static const int bmap[] = { |
10 | -1, | |
11 | -1, -1, 2, -1, 3, -1, 4, 14, -1, 15, 17, 18, 27, -1, 22, 23, -1, 24, 10, -1, | |
12 | 9, 25, 11, 8, -1, 7, -1, -1, 5, -1, 6, 12, 13, -1, 19, 16, 21, 20, -1, 21, | |
13 | }; | |
14 | static const int imap[] = { | |
15 | -1, -1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, | |
16 | 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, 27, | |
17 | }; | |
18 | static const int *umap = bmap; | |
19 | static int mapn = sizeof(bmap) / sizeof(*bmap); | |
7243cbb2 | 20 | static int preserve = 0; |
cc450aa9 FT |
21 | |
22 | static int mappin(int num) | |
23 | { | |
24 | if((num < 0) || (num >= mapn)) | |
25 | return(-1); | |
26 | return(umap[num]); | |
27 | } | |
28 | ||
7243cbb2 FT |
29 | static void export(int p) |
30 | { | |
31 | char path[256]; | |
32 | FILE *fp; | |
33 | int rp; | |
34 | ||
35 | if((rp = mappin(p)) < 0) | |
0437debd | 36 | errx(1, "%i: no such port", p); |
7243cbb2 FT |
37 | sprintf(path, "/sys/class/gpio/gpio%i", rp); |
38 | if(!access(path, R_OK | X_OK)) | |
39 | return; | |
40 | if(preserve) | |
41 | errx(2, "gpio%i: not exported", rp); | |
42 | sprintf(path, "/sys/class/gpio/export"); | |
43 | if((fp = fopen(path, "w")) == NULL) | |
44 | err(1, "%s", path); | |
45 | fprintf(fp, "%i\n", rp); fflush(fp); | |
46 | if(ferror(fp)) | |
47 | errx(1, "gpio%i: could not export", rp); | |
48 | fclose(fp); | |
49 | sprintf(path, "/sys/class/gpio/gpio%i", rp); | |
50 | if(access(path, R_OK | X_OK)) | |
51 | errx(1, "gpio%i: still not available after export", rp); | |
52 | } | |
53 | ||
0437debd | 54 | static void checkdir(int rp, char *dir) |
35647167 FT |
55 | { |
56 | char path[256], line[256]; | |
57 | FILE *fp; | |
0437debd FT |
58 | int rv; |
59 | size_t ln; | |
35647167 | 60 | |
cc450aa9 | 61 | sprintf(path, "/sys/class/gpio/gpio%i/direction", rp); |
35647167 FT |
62 | if((fp = fopen(path, "r")) == NULL) |
63 | err(1, "%s", path); | |
64 | rv = !!fgets(line, sizeof(line), fp); | |
65 | fclose(fp); | |
0437debd FT |
66 | if(!rv || ((ln = strlen(line)) < 1) || (line[ln - 1] != '\n')) |
67 | errx(1, "gpio%i: could not read direction", rp); | |
68 | line[ln - 1] = 0; | |
69 | if(strcmp(line, dir)) { | |
7243cbb2 | 70 | if(preserve) |
0437debd | 71 | errx(2, "gpio%i: direction not set to %s", rp, dir); |
35647167 FT |
72 | if((fp = fopen(path, "w")) == NULL) |
73 | err(1, "%s", path); | |
0437debd | 74 | fprintf(fp, "%s\n", dir); fflush(fp); |
35647167 | 75 | if(ferror(fp)) |
0437debd | 76 | errx(1, "gpio%i: could not set to direction to %s", rp, dir); |
35647167 FT |
77 | fclose(fp); |
78 | } | |
0437debd FT |
79 | } |
80 | ||
81 | static void setport(int p, int v) | |
82 | { | |
83 | char path[256]; | |
84 | FILE *fp; | |
85 | int rp; | |
86 | ||
87 | if((rp = mappin(p)) < 0) | |
88 | errx(1, "%i: no such port", p); | |
89 | checkdir(rp, "out"); | |
cc450aa9 | 90 | sprintf(path, "/sys/class/gpio/gpio%i/value", rp); |
35647167 FT |
91 | if((fp = fopen(path, "w")) == NULL) |
92 | err(1, "%s", path); | |
93 | fprintf(fp, "%i\n", v); fflush(fp); | |
94 | if(ferror(fp)) | |
cc450aa9 | 95 | errx(1, "gpio%i: could not set value", rp); |
35647167 FT |
96 | fclose(fp); |
97 | } | |
98 | ||
0437debd FT |
99 | static int getport(int p) |
100 | { | |
101 | char path[256], line[256], *ep; | |
102 | FILE *fp; | |
103 | int rv, rp; | |
104 | size_t ln; | |
105 | ||
106 | if((rp = mappin(p)) < 0) | |
107 | errx(1, "%i: no such port", p); | |
108 | checkdir(rp, "in"); | |
109 | sprintf(path, "/sys/class/gpio/gpio%i/value", rp); | |
110 | if((fp = fopen(path, "r")) == NULL) | |
111 | err(1, "%s", path); | |
112 | rv = !!fgets(line, sizeof(line), fp); | |
113 | fclose(fp); | |
114 | if(!rv || ((ln = strlen(line)) < 1) || (line[ln - 1] != '\n')) | |
115 | errx(1, "gpio%i: could not read direction", rp); | |
116 | line[ln - 1] = 0; | |
117 | rv = (int)strtol(line, &ep, 10); | |
118 | if(*ep) | |
119 | errx(1, "gpio%i: unexpected contents: %s", rp, line); | |
120 | return(rv); | |
121 | } | |
122 | ||
cc450aa9 FT |
123 | static void usage(FILE *out) |
124 | { | |
dbf61e61 | 125 | fprintf(out, "usage: gpio [-hip] {PORT=VAL|PORT==VAL|PORT?}...\n"); |
cc450aa9 FT |
126 | } |
127 | ||
35647167 FT |
128 | int main(int argc, char **argv) |
129 | { | |
cc450aa9 | 130 | int c, i, port, val; |
0437debd | 131 | char *e; |
35647167 | 132 | |
7243cbb2 | 133 | while((c = getopt(argc, argv, "hip")) >= 0) { |
cc450aa9 FT |
134 | switch(c) { |
135 | case 'h': | |
136 | usage(stdout); | |
137 | return(0); | |
138 | case 'i': | |
139 | umap = imap; | |
140 | mapn = sizeof(imap) / sizeof(*imap); | |
141 | break; | |
7243cbb2 FT |
142 | case 'p': |
143 | preserve = 1; | |
144 | break; | |
cc450aa9 FT |
145 | default: |
146 | usage(stderr); | |
147 | return(1); | |
148 | } | |
149 | } | |
150 | if(optind >= argc) { | |
151 | usage(stderr); | |
152 | return(1); | |
153 | } | |
154 | for(i = optind; i < argc; i++) { | |
35647167 | 155 | port = strtol(argv[i], &e, 10); |
0437debd FT |
156 | if((e > argv[i]) && (e[0] == '=') && (e[1] == '=')) { |
157 | val = strtol(e + 2, &e, 10); | |
158 | if(*e) | |
159 | errx(1, "gpio: %s: not of the form PORT==VAL", argv[i]); | |
160 | export(port); | |
161 | return(getport(port) != val); | |
162 | } else if((e > argv[i]) && (e[0] == '=')) { | |
163 | val = strtol(e + 1, &e, 10); | |
164 | if(*e) | |
165 | errx(1, "gpio: %s: not of the form PORT=VAL", argv[i]); | |
166 | export(port); | |
167 | setport(port, val); | |
168 | } else if((e > argv[i]) && (e[0] == '?') && !e[1]) { | |
169 | export(port); | |
170 | printf("%i\n", getport(port)); | |
171 | } else { | |
172 | errx(1, "gpio: %s: not a valid argument", argv[i]); | |
35647167 | 173 | } |
35647167 FT |
174 | } |
175 | return(0); | |
176 | } | |
cc450aa9 FT |
177 | |
178 | /* | |
179 | * Local Variables: | |
0437debd | 180 | * compile-command: "gcc -Wall -g -O2 -march=native -c -o gpio.o gpio.c && gcc -o gpio gpio.o" |
cc450aa9 FT |
181 | * End: |
182 | */ |