xref: /freebsd/usr.sbin/i2c/i2c.c (revision f4b37ed0f8b307b1f3f0f630ca725d68f1dff30d)
1 /*-
2  * Copyright (C) 2008-2009 Semihalf, Michal Hajduk and Bartlomiej Sieka
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <err.h>
31 #include <errno.h>
32 #include <sysexits.h>
33 #include <fcntl.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <stdarg.h>
38 #include <unistd.h>
39 #include <sys/ioctl.h>
40 
41 #include <dev/iicbus/iic.h>
42 
43 #define	I2C_DEV			"/dev/iic0"
44 #define	I2C_MODE_NOTSET		0
45 #define	I2C_MODE_NONE		1
46 #define	I2C_MODE_STOP_START	2
47 #define	I2C_MODE_REPEATED_START	3
48 
49 struct options {
50 	int	width;
51 	int	count;
52 	int	verbose;
53 	int	addr_set;
54 	int	binary;
55 	int	scan;
56 	int	skip;
57 	int	reset;
58 	int	mode;
59 	char	dir;
60 	uint32_t	addr;
61 	uint32_t	off;
62 };
63 
64 struct skip_range {
65 	int	start;
66 	int	end;
67 };
68 
69 __dead2 static void
70 usage(void)
71 {
72 
73 	fprintf(stderr, "usage: %s -a addr [-f device] [-d [r|w]] [-o offset] "
74 	    "[-w [0|8|16]] [-c count] [-m [ss|rs|no]] [-b] [-v]\n",
75 	    getprogname());
76 	fprintf(stderr, "       %s -s [-f device] [-n skip_addr] -v\n",
77 	    getprogname());
78 	fprintf(stderr, "       %s -r [-f device] -v\n", getprogname());
79 	exit(EX_USAGE);
80 }
81 
82 static struct skip_range
83 skip_get_range(char *skip_addr)
84 {
85 	struct skip_range addr_range;
86 	char *token;
87 
88 	addr_range.start = 0;
89 	addr_range.end = 0;
90 
91 	token = strsep(&skip_addr, "..");
92 	if (token) {
93 		addr_range.start = strtoul(token, 0, 16);
94 		token = strsep(&skip_addr, "..");
95 		if ((token != NULL) && !atoi(token)) {
96 			token = strsep(&skip_addr, "..");
97 			if (token)
98 				addr_range.end = strtoul(token, 0, 16);
99 		}
100 	}
101 
102 	return (addr_range);
103 }
104 
105 /* Parse the string to get hex 7 bits addresses */
106 static int
107 skip_get_tokens(char *skip_addr, int *sk_addr, int max_index)
108 {
109 	char *token;
110 	int i;
111 
112 	for (i = 0; i < max_index; i++) {
113 		token = strsep(&skip_addr, ":");
114 		if (token == NULL)
115 			break;
116 		sk_addr[i] = strtoul(token, 0, 16);
117 	}
118 	return (i);
119 }
120 
121 static int
122 scan_bus(struct iiccmd cmd, char *dev, int skip, char *skip_addr)
123 {
124 	struct skip_range addr_range = { 0, 0 };
125 	int *tokens, fd, error, i, index, j;
126 	int len = 0, do_skip = 0, no_range = 1;
127 
128 	fd = open(dev, O_RDWR);
129 	if (fd == -1) {
130 		fprintf(stderr, "Error opening I2C controller (%s) for "
131 		    "scanning: %s\n", dev, strerror(errno));
132 		return (EX_NOINPUT);
133 	}
134 
135 	if (skip) {
136 		len = strlen(skip_addr);
137 		if (strstr(skip_addr, "..") != NULL) {
138 			addr_range = skip_get_range(skip_addr);
139 			no_range = 0;
140 		} else {
141 			tokens = (int *)malloc((len / 2 + 1) * sizeof(int));
142 			if (tokens == NULL) {
143 				fprintf(stderr, "Error allocating tokens "
144 				    "buffer\n");
145 				error = -1;
146 				goto out;
147 			}
148 			index = skip_get_tokens(skip_addr, tokens,
149 			    len / 2 + 1);
150 		}
151 
152 		if (!no_range && (addr_range.start > addr_range.end)) {
153 			fprintf(stderr, "Skip address out of range\n");
154 			error = -1;
155 			goto out;
156 		}
157 	}
158 
159 	printf("Scanning I2C devices on %s: ", dev);
160 	for (i = 1; i < 127; i++) {
161 
162 		if (skip && ( addr_range.start < addr_range.end)) {
163 			if (i >= addr_range.start && i <= addr_range.end)
164 				continue;
165 
166 		} else if (skip && no_range)
167 			for (j = 0; j < index; j++) {
168 				if (tokens[j] == i) {
169 					do_skip = 1;
170 					break;
171 				}
172 			}
173 
174 		if (do_skip) {
175 			do_skip = 0;
176 			continue;
177 		}
178 
179 		cmd.slave = i << 1;
180 		cmd.last = 1;
181 		cmd.count = 0;
182 		error = ioctl(fd, I2CRSTCARD, &cmd);
183 		if (error)
184 			goto out;
185 
186 		cmd.slave = i << 1;
187 		cmd.last = 1;
188 		error = ioctl(fd, I2CSTART, &cmd);
189 		if (!error)
190 			printf("%x ", i);
191 		cmd.slave = i << 1;
192 		cmd.last = 1;
193 		error = ioctl(fd, I2CSTOP, &cmd);
194 	}
195 	printf("\n");
196 
197 	error = ioctl(fd, I2CRSTCARD, &cmd);
198 out:
199 	close(fd);
200 	if (skip && no_range)
201 		free(tokens);
202 
203 	if (error) {
204 		fprintf(stderr, "Error scanning I2C controller (%s): %s\n",
205 		    dev, strerror(errno));
206 		return (EX_NOINPUT);
207 	} else
208 		return (EX_OK);
209 }
210 
211 static int
212 reset_bus(struct iiccmd cmd, char *dev)
213 {
214 	int fd, error;
215 
216 	fd = open(dev, O_RDWR);
217 	if (fd == -1) {
218 		fprintf(stderr, "Error opening I2C controller (%s) for "
219 		    "resetting: %s\n", dev, strerror(errno));
220 		return (EX_NOINPUT);
221 	}
222 
223 	printf("Resetting I2C controller on %s: ", dev);
224 	error = ioctl(fd, I2CRSTCARD, &cmd);
225 	close (fd);
226 
227 	if (error) {
228 		printf("error: %s\n", strerror(errno));
229 		return (EX_IOERR);
230 	} else {
231 		printf("OK\n");
232 		return (EX_OK);
233 	}
234 }
235 
236 static char *
237 prepare_buf(int size, uint32_t off)
238 {
239 	char *buf;
240 
241 	buf = malloc(size);
242 	if (buf == NULL)
243 		return (buf);
244 
245 	if (size == 1)
246 		buf[0] = off & 0xff;
247 	else if (size == 2) {
248 		buf[0] = (off >> 8) & 0xff;
249 		buf[1] = off & 0xff;
250 	}
251 
252 	return (buf);
253 }
254 
255 static int
256 i2c_write(char *dev, struct options i2c_opt, char *i2c_buf)
257 {
258 	struct iiccmd cmd;
259 	int ch, i, error, fd, bufsize;
260 	char *err_msg, *buf;
261 
262 	/*
263 	 * Read data to be written to the chip from stdin
264 	 */
265 	if (i2c_opt.verbose && !i2c_opt.binary)
266 		fprintf(stderr, "Enter %u bytes of data: ", i2c_opt.count);
267 
268 	for (i = 0; i < i2c_opt.count; i++) {
269 		ch = getchar();
270 		if (ch == EOF) {
271 			free(i2c_buf);
272 			err(1, "not enough data, exiting\n");
273 		}
274 		i2c_buf[i] = ch;
275 	}
276 
277 	fd = open(dev, O_RDWR);
278 	if (fd == -1) {
279 		free(i2c_buf);
280 		err(1, "open failed");
281 	}
282 
283 	/*
284 	 * Write offset where the data will go
285 	 */
286 	cmd.slave = i2c_opt.addr;
287 	error = ioctl(fd, I2CSTART, &cmd);
288 	if (error == -1) {
289 		err_msg = "ioctl: error sending start condition";
290 		goto err1;
291 	}
292 
293 	if (i2c_opt.width) {
294 		bufsize = i2c_opt.width / 8;
295 		buf = prepare_buf(bufsize, i2c_opt.off);
296 		if (buf == NULL) {
297 			err_msg = "error: offset malloc";
298 			goto err1;
299 		}
300 
301 		cmd.count = bufsize;
302 		cmd.buf = buf;
303 		error = ioctl(fd, I2CWRITE, &cmd);
304 		free(buf);
305 		if (error == -1) {
306 			err_msg = "ioctl: error when write offset";
307 			goto err1;
308 		}
309 	}
310 
311 	/* Mode - stop start */
312 	if (i2c_opt.mode == I2C_MODE_STOP_START) {
313 		cmd.slave = i2c_opt.addr;
314 		error = ioctl(fd, I2CSTOP, &cmd);
315 		if (error == -1) {
316 			err_msg = "ioctl: error sending stop condition";
317 			goto err2;
318 		}
319 		cmd.slave = i2c_opt.addr;
320 		error = ioctl(fd, I2CSTART, &cmd);
321 		if (error == -1) {
322 			err_msg = "ioctl: error sending start condition";
323 			goto err1;
324 		}
325 	}
326 	/* Mode - repeated start */
327 	if (i2c_opt.mode == I2C_MODE_REPEATED_START) {
328 		cmd.slave = i2c_opt.addr;
329 		error = ioctl(fd, I2CRPTSTART, &cmd);
330 		if (error == -1) {
331 			err_msg = "ioctl: error sending repeated start "
332 			    "condition";
333 			goto err1;
334 		}
335 	}
336 
337 	/*
338 	 * Write the data
339 	 */
340 	cmd.count = i2c_opt.count;
341 	cmd.buf = i2c_buf;
342 	cmd.last = 0;
343 	error = ioctl(fd, I2CWRITE, &cmd);
344 	if (error == -1) {
345 		err_msg = "ioctl: error when write";
346 		goto err1;
347 	}
348 	cmd.slave = i2c_opt.addr;
349 	error = ioctl(fd, I2CSTOP, &cmd);
350 	if (error == -1) {
351 		err_msg = "ioctl: error sending stop condition";
352 		goto err2;
353 	}
354 
355 	close(fd);
356 	return (0);
357 
358 err1:
359 	cmd.slave = i2c_opt.addr;
360 	error = ioctl(fd, I2CSTOP, &cmd);
361 	if (error == -1)
362 		fprintf(stderr, "error sending stop condtion\n");
363 err2:
364 	if (err_msg)
365 		fprintf(stderr, "%s", err_msg);
366 
367 	close(fd);
368 	return (1);
369 }
370 
371 static int
372 i2c_read(char *dev, struct options i2c_opt, char *i2c_buf)
373 {
374 	struct iiccmd cmd;
375 	int i, fd, error, bufsize;
376 	char *err_msg, data = 0, *buf;
377 
378 	fd = open(dev, O_RDWR);
379 	if (fd == -1)
380 		err(1, "open failed");
381 
382 	bzero(&cmd, sizeof(cmd));
383 
384 	if (i2c_opt.width) {
385 		cmd.slave = i2c_opt.addr;
386 		cmd.count = 1;
387 		cmd.last = 0;
388 		cmd.buf = &data;
389 		error = ioctl(fd, I2CSTART, &cmd);
390 		if (error == -1) {
391 			err_msg = "ioctl: error sending start condition";
392 			goto err1;
393 		}
394 		bufsize = i2c_opt.width / 8;
395 		buf = prepare_buf(bufsize, i2c_opt.off);
396 		if (buf == NULL) {
397 			err_msg = "error: offset malloc";
398 			goto err1;
399 		}
400 
401 		cmd.count = bufsize;
402 		cmd.buf = buf;
403 		cmd.last = 0;
404 		error = ioctl(fd, I2CWRITE, &cmd);
405 		free(buf);
406 		if (error == -1) {
407 			err_msg = "ioctl: error when write offset";
408 			goto err1;
409 		}
410 
411 		if (i2c_opt.mode == I2C_MODE_STOP_START) {
412 			cmd.slave = i2c_opt.addr;
413 			error = ioctl(fd, I2CSTOP, &cmd);
414 			if (error == -1) {
415 				err_msg = "error sending stop condtion\n";
416 				goto err2;
417 			}
418 		}
419 	}
420 	cmd.slave = i2c_opt.addr;
421 	cmd.count = 1;
422 	cmd.last = 0;
423 	cmd.buf = &data;
424 	if (i2c_opt.mode == I2C_MODE_STOP_START) {
425 		error = ioctl(fd, I2CSTART, &cmd);
426 		if (error == -1) {
427 			err_msg = "ioctl: error sending start condition";
428 			goto err1;
429 		}
430 	} else if (i2c_opt.mode == I2C_MODE_REPEATED_START) {
431 		error = ioctl(fd, I2CRPTSTART, &cmd);
432 		if (error == -1) {
433 			err_msg = "ioctl: error sending repeated start "
434 			    "condition";
435 			goto err1;
436 		}
437 	}
438 	error = ioctl(fd, I2CSTOP, &cmd);
439 	if (error == -1) {
440 		err_msg = "error sending stop condtion\n";
441 		goto err2;
442 	}
443 
444 	for (i = 0; i < i2c_opt.count; i++) {
445 		error = read(fd, &i2c_buf[i], 1);
446 		if (error == -1) {
447 			err_msg = "ioctl: error while reading";
448 			goto err1;
449 		}
450 	}
451 
452 	close(fd);
453 	return (0);
454 
455 err1:
456 	cmd.slave = i2c_opt.addr;
457 	error = ioctl(fd, I2CSTOP, &cmd);
458 	if (error == -1)
459 		fprintf(stderr, "error sending stop condtion\n");
460 err2:
461 	if (err_msg)
462 		fprintf(stderr, "%s", err_msg);
463 
464 	close(fd);
465 	return (1);
466 }
467 
468 int
469 main(int argc, char** argv)
470 {
471 	struct iiccmd cmd;
472 	struct options i2c_opt;
473 	char *dev, *skip_addr, *i2c_buf;
474 	int error, chunk_size, i, j, ch;
475 
476 	errno = 0;
477 	error = 0;
478 
479 	/* Line-break the output every chunk_size bytes */
480 	chunk_size = 16;
481 
482 	dev = I2C_DEV;
483 
484 	/* Default values */
485 	i2c_opt.addr_set = 0;
486 	i2c_opt.off = 0;
487 	i2c_opt.verbose = 0;
488 	i2c_opt.dir = 'r';	/* direction = read */
489 	i2c_opt.width = 8;
490 	i2c_opt.count = 1;
491 	i2c_opt.binary = 0;	/* ASCII text output */
492 	i2c_opt.scan = 0;	/* no bus scan */
493 	i2c_opt.skip = 0;	/* scan all addresses */
494 	i2c_opt.reset = 0;	/* no bus reset */
495 	i2c_opt.mode = I2C_MODE_NOTSET;
496 
497 	while ((ch = getopt(argc, argv, "a:f:d:o:w:c:m:n:sbvrh")) != -1) {
498 		switch(ch) {
499 		case 'a':
500 			i2c_opt.addr = (strtoul(optarg, 0, 16) << 1);
501 			if (i2c_opt.addr == 0 && errno == EINVAL)
502 				i2c_opt.addr_set = 0;
503 			else
504 				i2c_opt.addr_set = 1;
505 			break;
506 		case 'f':
507 			dev = optarg;
508 			break;
509 		case 'd':
510 			i2c_opt.dir = optarg[0];
511 			break;
512 		case 'o':
513 			i2c_opt.off = strtoul(optarg, 0, 16);
514 			if (i2c_opt.off == 0 && errno == EINVAL)
515 				error = 1;
516 			break;
517 		case 'w':
518 			i2c_opt.width = atoi(optarg);
519 			break;
520 		case 'c':
521 			i2c_opt.count = atoi(optarg);
522 			break;
523 		case 'm':
524 			if (!strcmp(optarg, "no"))
525 				i2c_opt.mode = I2C_MODE_NONE;
526 			else if (!strcmp(optarg, "ss"))
527 				i2c_opt.mode = I2C_MODE_STOP_START;
528 			else if (!strcmp(optarg, "rs"))
529 				i2c_opt.mode = I2C_MODE_REPEATED_START;
530 			else
531 				usage();
532 			break;
533 		case 'n':
534 			i2c_opt.skip = 1;
535 			skip_addr = optarg;
536 			break;
537 		case 's':
538 			i2c_opt.scan = 1;
539 			break;
540 		case 'b':
541 			i2c_opt.binary = 1;
542 			break;
543 		case 'v':
544 			i2c_opt.verbose = 1;
545 			break;
546 		case 'r':
547 			i2c_opt.reset = 1;
548 			break;
549 		case 'h':
550 		default:
551 			usage();
552 		}
553 	}
554 	argc -= optind;
555 	argv += optind;
556 
557 	/* Set default mode if option -m is not specified */
558 	if (i2c_opt.mode == I2C_MODE_NOTSET) {
559 		if (i2c_opt.dir == 'r')
560 			i2c_opt.mode = I2C_MODE_STOP_START;
561 		else if (i2c_opt.dir == 'w')
562 			i2c_opt.mode = I2C_MODE_NONE;
563 	}
564 
565 	/* Basic sanity check of command line arguments */
566 	if (i2c_opt.scan) {
567 		if (i2c_opt.addr_set)
568 			usage();
569 	} else if (i2c_opt.reset) {
570 		if (i2c_opt.addr_set)
571 			usage();
572 	} else if (error) {
573 		usage();
574 	} else if ((i2c_opt.dir == 'r' || i2c_opt.dir == 'w')) {
575 		if ((i2c_opt.addr_set == 0) ||
576 		    !(i2c_opt.width == 0 || i2c_opt.width == 8 ||
577 		    i2c_opt.width == 16))
578 		usage();
579 	}
580 
581 	if (i2c_opt.verbose)
582 		fprintf(stderr, "dev: %s, addr: 0x%x, r/w: %c, "
583 		    "offset: 0x%02x, width: %u, count: %u\n", dev,
584 		    i2c_opt.addr >> 1, i2c_opt.dir, i2c_opt.off,
585 		    i2c_opt.width, i2c_opt.count);
586 
587 	if (i2c_opt.scan)
588 		exit(scan_bus(cmd, dev, i2c_opt.skip, skip_addr));
589 
590 	if (i2c_opt.reset)
591 		exit(reset_bus(cmd, dev));
592 
593 	i2c_buf = malloc(i2c_opt.count);
594 	if (i2c_buf == NULL)
595 		err(1, "data malloc");
596 
597 	if (i2c_opt.dir == 'w') {
598 		error = i2c_write(dev, i2c_opt, i2c_buf);
599 		if (error) {
600 			free(i2c_buf);
601 			return (1);
602 		}
603 	}
604 	if (i2c_opt.dir == 'r') {
605 		error = i2c_read(dev, i2c_opt, i2c_buf);
606 		if (error) {
607 			free(i2c_buf);
608 			return (1);
609 		}
610 	}
611 
612 	if (i2c_opt.verbose)
613 		fprintf(stderr, "\nData %s (hex):\n", i2c_opt.dir == 'r' ?
614 		    "read" : "written");
615 
616 	i = 0;
617 	j = 0;
618 	while (i < i2c_opt.count) {
619 		if (i2c_opt.verbose || (i2c_opt.dir == 'r' &&
620 		    !i2c_opt.binary))
621 			fprintf (stderr, "%02hhx ", i2c_buf[i++]);
622 
623 		if (i2c_opt.dir == 'r' && i2c_opt.binary) {
624 			fprintf(stdout, "%c", i2c_buf[j++]);
625 			if(!i2c_opt.verbose)
626 				i++;
627 		}
628 		if (!i2c_opt.verbose && (i2c_opt.dir == 'w'))
629 			break;
630 		if ((i % chunk_size) == 0)
631 			fprintf(stderr, "\n");
632 	}
633 	if ((i % chunk_size) != 0)
634 		fprintf(stderr, "\n");
635 
636 	free(i2c_buf);
637 	return (0);
638 }
639