1 /* vi: set sw=4 ts=4: */
2 /*
3  * Minimal i2c-tools implementation for busybox.
4  * Parts of code ported from i2c-tools:
5  * 		http://www.lm-sensors.org/wiki/I2CTools.
6  *
7  * Copyright (C) 2014 by Bartosz Golaszewski <bartekgola@gmail.com>
8  *
9  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
10  */
11 //config:config I2CGET
12 //config:	bool "i2cget (5.5 kb)"
13 //config:	default y
14 //config:	help
15 //config:	Read from I2C/SMBus chip registers.
16 //config:
17 //config:config I2CSET
18 //config:	bool "i2cset (6.7 kb)"
19 //config:	default y
20 //config:	help
21 //config:	Set I2C registers.
22 //config:
23 //config:config I2CDUMP
24 //config:	bool "i2cdump (7.1 kb)"
25 //config:	default y
26 //config:	help
27 //config:	Examine I2C registers.
28 //config:
29 //config:config I2CDETECT
30 //config:	bool "i2cdetect (7.1 kb)"
31 //config:	default y
32 //config:	help
33 //config:	Detect I2C chips.
34 //config:
35 //config:config I2CTRANSFER
36 //config:	bool "i2ctransfer (4.0 kb)"
37 //config:	default y
38 //config:	help
39 //config:	Send user-defined I2C messages in one transfer.
40 //config:
41 
42 //applet:IF_I2CGET(APPLET(i2cget, BB_DIR_USR_SBIN, BB_SUID_DROP))
43 //applet:IF_I2CSET(APPLET(i2cset, BB_DIR_USR_SBIN, BB_SUID_DROP))
44 //applet:IF_I2CDUMP(APPLET(i2cdump, BB_DIR_USR_SBIN, BB_SUID_DROP))
45 //applet:IF_I2CDETECT(APPLET(i2cdetect, BB_DIR_USR_SBIN, BB_SUID_DROP))
46 //applet:IF_I2CTRANSFER(APPLET(i2ctransfer, BB_DIR_USR_SBIN, BB_SUID_DROP))
47 /* not NOEXEC: if hw operation stalls, use less memory in "hung" process */
48 
49 //kbuild:lib-$(CONFIG_I2CGET) += i2c_tools.o
50 //kbuild:lib-$(CONFIG_I2CSET) += i2c_tools.o
51 //kbuild:lib-$(CONFIG_I2CDUMP) += i2c_tools.o
52 //kbuild:lib-$(CONFIG_I2CDETECT) += i2c_tools.o
53 //kbuild:lib-$(CONFIG_I2CTRANSFER) += i2c_tools.o
54 
55 /*
56  * Unsupported stuff:
57  *
58  * - upstream i2c-tools can also look-up i2c busses by name, we only accept
59  *   numbers,
60  * - bank and bankreg parameters for i2cdump are not supported because of
61  *   their limited usefulness (see i2cdump manual entry for more info),
62  * - i2cdetect doesn't look for bus info in /proc as it does in upstream, but
63  *   it shouldn't be a problem in modern kernels.
64  */
65 
66 #include "libbb.h"
67 
68 #include <linux/i2c.h>
69 
70 #define I2CDUMP_NUM_REGS		256
71 
72 #define I2CDETECT_MODE_AUTO		0
73 #define I2CDETECT_MODE_QUICK		1
74 #define I2CDETECT_MODE_READ		2
75 
76 /* linux/i2c-dev.h from i2c-tools overwrites the one from linux uapi
77  * and defines symbols already defined by linux/i2c.h.
78  * Also, it defines a bunch of static inlines which we would rather NOT
79  * inline. What a mess.
80  * We need only these definitions from linux/i2c-dev.h:
81  */
82 #define I2C_SLAVE			0x0703
83 #define I2C_SLAVE_FORCE			0x0706
84 #define I2C_FUNCS			0x0705
85 #define I2C_PEC				0x0708
86 #define I2C_SMBUS			0x0720
87 #define I2C_RDWR			0x0707
88 #define I2C_RDWR_IOCTL_MAX_MSGS		42
89 #define I2C_RDWR_IOCTL_MAX_MSGS_STR	"42"
90 struct i2c_smbus_ioctl_data {
91 	__u8 read_write;
92 	__u8 command;
93 	__u32 size;
94 	union i2c_smbus_data *data;
95 };
96 struct i2c_rdwr_ioctl_data {
97 	struct i2c_msg *msgs;	/* pointers to i2c_msgs */
98 	__u32 nmsgs;		/* number of i2c_msgs */
99 };
100 /* end linux/i2c-dev.h */
101 
102 /*
103  * This is needed for ioctl_or_perror_and_die() since it only accepts pointers.
104  */
itoptr(int i)105 static ALWAYS_INLINE void *itoptr(int i)
106 {
107 	return (void*)(intptr_t)i;
108 }
109 
i2c_smbus_access(int fd,char read_write,uint8_t cmd,int size,union i2c_smbus_data * data)110 static int32_t i2c_smbus_access(int fd, char read_write, uint8_t cmd,
111 				int size, union i2c_smbus_data *data)
112 {
113 	struct i2c_smbus_ioctl_data args;
114 
115 	args.read_write = read_write;
116 	args.command = cmd;
117 	args.size = size;
118 	args.data = data;
119 
120 	return ioctl(fd, I2C_SMBUS, &args);
121 }
122 
i2c_smbus_read_byte(int fd)123 static int32_t i2c_smbus_read_byte(int fd)
124 {
125 	union i2c_smbus_data data;
126 	int err;
127 
128 	err = i2c_smbus_access(fd, I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &data);
129 	if (err < 0)
130 		return err;
131 
132 	return data.byte;
133 }
134 
135 #if ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP
i2c_smbus_write_byte(int fd,uint8_t val)136 static int32_t i2c_smbus_write_byte(int fd, uint8_t val)
137 {
138 	return i2c_smbus_access(fd, I2C_SMBUS_WRITE,
139 				val, I2C_SMBUS_BYTE, NULL);
140 }
141 
i2c_smbus_read_byte_data(int fd,uint8_t cmd)142 static int32_t i2c_smbus_read_byte_data(int fd, uint8_t cmd)
143 {
144 	union i2c_smbus_data data;
145 	int err;
146 
147 	err = i2c_smbus_access(fd, I2C_SMBUS_READ, cmd,
148 			       I2C_SMBUS_BYTE_DATA, &data);
149 	if (err < 0)
150 		return err;
151 
152 	return data.byte;
153 }
154 
i2c_smbus_read_word_data(int fd,uint8_t cmd)155 static int32_t i2c_smbus_read_word_data(int fd, uint8_t cmd)
156 {
157 	union i2c_smbus_data data;
158 	int err;
159 
160 	err = i2c_smbus_access(fd, I2C_SMBUS_READ, cmd,
161 			       I2C_SMBUS_WORD_DATA, &data);
162 	if (err < 0)
163 		return err;
164 
165 	return data.word;
166 }
167 #endif /* ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP */
168 
169 #if ENABLE_I2CSET
i2c_smbus_write_byte_data(int file,uint8_t cmd,uint8_t value)170 static int32_t i2c_smbus_write_byte_data(int file,
171 					 uint8_t cmd, uint8_t value)
172 {
173 	union i2c_smbus_data data;
174 
175 	data.byte = value;
176 
177 	return i2c_smbus_access(file, I2C_SMBUS_WRITE, cmd,
178 				I2C_SMBUS_BYTE_DATA, &data);
179 }
180 
i2c_smbus_write_word_data(int file,uint8_t cmd,uint16_t value)181 static int32_t i2c_smbus_write_word_data(int file, uint8_t cmd, uint16_t value)
182 {
183 	union i2c_smbus_data data;
184 
185 	data.word = value;
186 
187 	return i2c_smbus_access(file, I2C_SMBUS_WRITE, cmd,
188 				I2C_SMBUS_WORD_DATA, &data);
189 }
190 
i2c_smbus_write_block_data(int file,uint8_t cmd,uint8_t length,const uint8_t * values)191 static int32_t i2c_smbus_write_block_data(int file, uint8_t cmd,
192 				   uint8_t length, const uint8_t *values)
193 {
194 	union i2c_smbus_data data;
195 
196 	if (length > I2C_SMBUS_BLOCK_MAX)
197 		length = I2C_SMBUS_BLOCK_MAX;
198 
199 	memcpy(data.block+1, values, length);
200 	data.block[0] = length;
201 
202 	return i2c_smbus_access(file, I2C_SMBUS_WRITE, cmd,
203 				I2C_SMBUS_BLOCK_DATA, &data);
204 }
205 
i2c_smbus_write_i2c_block_data(int file,uint8_t cmd,uint8_t length,const uint8_t * values)206 static int32_t i2c_smbus_write_i2c_block_data(int file, uint8_t cmd,
207 				       uint8_t length, const uint8_t *values)
208 {
209 	union i2c_smbus_data data;
210 
211 	if (length > I2C_SMBUS_BLOCK_MAX)
212 		length = I2C_SMBUS_BLOCK_MAX;
213 
214 	memcpy(data.block+1, values, length);
215 	data.block[0] = length;
216 
217 	return i2c_smbus_access(file, I2C_SMBUS_WRITE, cmd,
218 				I2C_SMBUS_I2C_BLOCK_BROKEN, &data);
219 }
220 #endif /* ENABLE_I2CSET */
221 
222 #if ENABLE_I2CDUMP
223 /*
224  * Returns the number of bytes read, vals must hold at
225  * least I2C_SMBUS_BLOCK_MAX bytes.
226  */
i2c_smbus_read_block_data(int fd,uint8_t cmd,uint8_t * vals)227 static int32_t i2c_smbus_read_block_data(int fd, uint8_t cmd, uint8_t *vals)
228 {
229 	union i2c_smbus_data data;
230 	int i, err;
231 
232 	err = i2c_smbus_access(fd, I2C_SMBUS_READ, cmd,
233 			       I2C_SMBUS_BLOCK_DATA, &data);
234 	if (err < 0)
235 		return err;
236 
237 	for (i = 1; i <= data.block[0]; i++)
238 		*vals++ = data.block[i];
239 	return data.block[0];
240 }
241 
i2c_smbus_read_i2c_block_data(int fd,uint8_t cmd,uint8_t len,uint8_t * vals)242 static int32_t i2c_smbus_read_i2c_block_data(int fd, uint8_t cmd,
243 					     uint8_t len, uint8_t *vals)
244 {
245 	union i2c_smbus_data data;
246 	int i, err;
247 
248 	if (len > I2C_SMBUS_BLOCK_MAX)
249 		len = I2C_SMBUS_BLOCK_MAX;
250 	data.block[0] = len;
251 
252 	err = i2c_smbus_access(fd, I2C_SMBUS_READ, cmd,
253 			       len == 32 ? I2C_SMBUS_I2C_BLOCK_BROKEN :
254 					   I2C_SMBUS_I2C_BLOCK_DATA, &data);
255 	if (err < 0)
256 		return err;
257 
258 	for (i = 1; i <= data.block[0]; i++)
259 		*vals++ = data.block[i];
260 	return data.block[0];
261 }
262 #endif /* ENABLE_I2CDUMP */
263 
264 #if ENABLE_I2CDETECT
i2c_smbus_write_quick(int fd,uint8_t val)265 static int32_t i2c_smbus_write_quick(int fd, uint8_t val)
266 {
267 	return i2c_smbus_access(fd, val, 0, I2C_SMBUS_QUICK, NULL);
268 }
269 #endif /* ENABLE_I2CDETECT */
270 
i2c_bus_lookup(const char * bus_str)271 static int i2c_bus_lookup(const char *bus_str)
272 {
273 	return xstrtou_range(bus_str, 10, 0, 0xfffff);
274 }
275 
276 #if ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP
i2c_parse_bus_addr(const char * addr_str)277 static int i2c_parse_bus_addr(const char *addr_str)
278 {
279 	/* Slave address must be in range 0x03 - 0x77. */
280 	return xstrtou_range(addr_str, 16, 0x03, 0x77);
281 }
282 
i2c_set_pec(int fd,int pec)283 static void i2c_set_pec(int fd, int pec)
284 {
285 	ioctl_or_perror_and_die(fd, I2C_PEC,
286 				itoptr(pec ? 1 : 0),
287 				"can't set PEC");
288 }
289 #endif
290 
291 #if ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP || ENABLE_I2CTRANSFER
i2c_set_slave_addr(int fd,int addr,int force)292 static void i2c_set_slave_addr(int fd, int addr, int force)
293 {
294 	ioctl_or_perror_and_die(fd, force ? I2C_SLAVE_FORCE : I2C_SLAVE,
295 				itoptr(addr),
296 				"can't set address to 0x%02x", addr);
297 }
298 #endif
299 
300 #if ENABLE_I2CGET || ENABLE_I2CSET
i2c_parse_data_addr(const char * data_addr)301 static int i2c_parse_data_addr(const char *data_addr)
302 {
303 	/* Data address must be an 8 bit integer. */
304 	return xstrtou_range(data_addr, 16, 0, 0xff);
305 }
306 #endif /* ENABLE_I2CGET || ENABLE_I2CSET */
307 
308 /*
309  * Opens the device file associated with given i2c bus.
310  *
311  * Upstream i2c-tools also support opening devices by i2c bus name
312  * but we drop it here for size reduction.
313  */
i2c_dev_open(int i2cbus)314 static int i2c_dev_open(int i2cbus)
315 {
316 	char filename[sizeof("/dev/i2c-%d") + sizeof(int)*3];
317 	int fd;
318 
319 	sprintf(filename, "/dev/i2c-%d", i2cbus);
320 	fd = open(filename, O_RDWR);
321 	if (fd < 0) {
322 		if (errno == ENOENT) {
323 			filename[8] = '/'; /* change to "/dev/i2c/%d" */
324 			fd = xopen(filename, O_RDWR);
325 		} else {
326 			bb_perror_msg_and_die("can't open '%s'", filename);
327 		}
328 	}
329 
330 	return fd;
331 }
332 
333 /* Size reducing helpers for xxx_check_funcs(). */
get_funcs_matrix(int fd,unsigned long * funcs)334 static void get_funcs_matrix(int fd, unsigned long *funcs)
335 {
336 	ioctl_or_perror_and_die(fd, I2C_FUNCS, funcs,
337 			"can't get adapter functionality matrix");
338 }
339 
340 #if ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP
check_funcs_test_end(int funcs,int pec,const char * err)341 static void check_funcs_test_end(int funcs, int pec, const char *err)
342 {
343 	if (pec && !(funcs & (I2C_FUNC_SMBUS_PEC | I2C_FUNC_I2C)))
344 		bb_simple_error_msg("warning: adapter does not support PEC");
345 
346 	if (err)
347 		bb_error_msg_and_die(
348 			"adapter has no %s capability", err);
349 }
350 #endif /* ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP */
351 
352 /*
353  * The below functions emit an error message and exit if the adapter doesn't
354  * support desired functionalities.
355  */
356 #if ENABLE_I2CGET || ENABLE_I2CDUMP
check_read_funcs(int fd,int mode,int data_addr,int pec)357 static void check_read_funcs(int fd, int mode, int data_addr, int pec)
358 {
359 	unsigned long funcs;
360 	const char *err = NULL;
361 
362 	get_funcs_matrix(fd, &funcs);
363 	switch (mode) {
364 	case I2C_SMBUS_BYTE:
365 		if (!(funcs & I2C_FUNC_SMBUS_READ_BYTE)) {
366 			err = "SMBus receive byte";
367 			break;
368 		}
369 		if (data_addr >= 0 && !(funcs & I2C_FUNC_SMBUS_WRITE_BYTE))
370 			err = "SMBus send byte";
371 		break;
372 	case I2C_SMBUS_BYTE_DATA:
373 		if (!(funcs & I2C_FUNC_SMBUS_READ_BYTE_DATA))
374 			err = "SMBus read byte";
375 		break;
376 	case I2C_SMBUS_WORD_DATA:
377 		if (!(funcs & I2C_FUNC_SMBUS_READ_WORD_DATA))
378 			err = "SMBus read word";
379 		break;
380 #if ENABLE_I2CDUMP
381 	case I2C_SMBUS_BLOCK_DATA:
382 		if (!(funcs & I2C_FUNC_SMBUS_READ_BLOCK_DATA))
383 			err = "SMBus block read";
384 		break;
385 
386 	case I2C_SMBUS_I2C_BLOCK_DATA:
387 		if (!(funcs & I2C_FUNC_SMBUS_READ_I2C_BLOCK))
388 			err = "I2C block read";
389 		break;
390 #endif /* ENABLE_I2CDUMP */
391 	default:
392 		bb_simple_error_msg_and_die("internal error");
393 	}
394 	check_funcs_test_end(funcs, pec, err);
395 }
396 #endif /* ENABLE_I2CGET || ENABLE_I2CDUMP */
397 
398 #if ENABLE_I2CSET
check_write_funcs(int fd,int mode,int pec)399 static void check_write_funcs(int fd, int mode, int pec)
400 {
401 	unsigned long funcs;
402 	const char *err = NULL;
403 
404 	get_funcs_matrix(fd, &funcs);
405 	switch (mode) {
406 	case I2C_SMBUS_BYTE:
407 		if (!(funcs & I2C_FUNC_SMBUS_WRITE_BYTE))
408 			err = "SMBus send byte";
409 		break;
410 
411 	case I2C_SMBUS_BYTE_DATA:
412 		if (!(funcs & I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
413 			err = "SMBus write byte";
414 		break;
415 
416 	case I2C_SMBUS_WORD_DATA:
417 		if (!(funcs & I2C_FUNC_SMBUS_WRITE_WORD_DATA))
418 			err = "SMBus write word";
419 		break;
420 
421 	case I2C_SMBUS_BLOCK_DATA:
422 		if (!(funcs & I2C_FUNC_SMBUS_WRITE_BLOCK_DATA))
423 			err = "SMBus block write";
424 		break;
425 	case I2C_SMBUS_I2C_BLOCK_DATA:
426 		if (!(funcs & I2C_FUNC_SMBUS_WRITE_I2C_BLOCK))
427 			err = "I2C block write";
428 		break;
429 	}
430 	check_funcs_test_end(funcs, pec, err);
431 }
432 #endif /* ENABLE_I2CSET */
433 
confirm_or_abort(void)434 static void confirm_or_abort(void)
435 {
436 	fprintf(stderr, "Continue? [y/N] ");
437 	if (!bb_ask_y_confirmation())
438 		bb_simple_error_msg_and_die("aborting");
439 }
440 
441 /*
442  * Return only if user confirms the action, abort otherwise.
443  *
444  * The messages displayed here are much less elaborate than their i2c-tools
445  * counterparts - this is done for size reduction.
446  */
confirm_action(int bus_addr,int mode,int data_addr,int pec)447 static void confirm_action(int bus_addr, int mode, int data_addr, int pec)
448 {
449 	bb_simple_error_msg("WARNING! This program can confuse your I2C bus");
450 
451 	/* Don't let the user break his/her EEPROMs */
452 	if (bus_addr >= 0x50 && bus_addr <= 0x57 && pec) {
453 		bb_simple_error_msg_and_die("this is I2C not smbus - using PEC on I2C "
454 			"devices may result in data loss, aborting");
455 	}
456 
457 	if (mode == I2C_SMBUS_BYTE && data_addr >= 0 && pec)
458 		bb_simple_error_msg("WARNING! May interpret a write byte command "
459 			"with PEC as a write byte data command");
460 
461 	if (pec)
462 		bb_simple_error_msg("PEC checking enabled");
463 
464 	confirm_or_abort();
465 }
466 
467 #if ENABLE_I2CGET
468 //usage:#define i2cget_trivial_usage
469 //usage:       "[-fy] BUS CHIP-ADDRESS [DATA-ADDRESS [MODE]]"
470 //usage:#define i2cget_full_usage "\n\n"
471 //usage:       "Read from I2C/SMBus chip registers"
472 //usage:     "\n"
473 //usage:     "\n	I2CBUS	I2C bus number"
474 //usage:     "\n	ADDRESS	0x03-0x77"
475 //usage:     "\nMODE is:"
476 //usage:     "\n	b	Read byte data (default)"
477 //usage:     "\n	w	Read word data"
478 //usage:     "\n	c	Write byte/read byte"
479 //usage:     "\n	Append p for SMBus PEC"
480 //usage:     "\n"
481 //usage:     "\n	-f	Force access"
482 //usage:     "\n	-y	Disable interactive mode"
483 int i2cget_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
i2cget_main(int argc UNUSED_PARAM,char ** argv)484 int i2cget_main(int argc UNUSED_PARAM, char **argv)
485 {
486 	const unsigned opt_f = (1 << 0), opt_y = (1 << 1);
487 
488 	int bus_num, bus_addr, data_addr = -1, status;
489 	int mode = I2C_SMBUS_BYTE, pec = 0, fd;
490 	unsigned opts;
491 
492 	opts = getopt32(argv, "^" "fy" "\0" "-2:?4"/*from 2 to 4 args*/);
493 	argv += optind;
494 
495 	bus_num = i2c_bus_lookup(argv[0]);
496 	bus_addr = i2c_parse_bus_addr(argv[1]);
497 
498 	if (argv[2]) {
499 		data_addr = i2c_parse_data_addr(argv[2]);
500 		mode = I2C_SMBUS_BYTE_DATA;
501 		if (argv[3]) {
502 			switch (argv[3][0]) {
503 			case 'b':	/* Already set */		break;
504 			case 'w':	mode = I2C_SMBUS_WORD_DATA;	break;
505 			case 'c':	mode = I2C_SMBUS_BYTE;		break;
506 			default:
507 				bb_simple_error_msg("invalid mode");
508 				bb_show_usage();
509 			}
510 			pec = argv[3][1] == 'p';
511 		}
512 	}
513 
514 	fd = i2c_dev_open(bus_num);
515 	check_read_funcs(fd, mode, data_addr, pec);
516 	i2c_set_slave_addr(fd, bus_addr, opts & opt_f);
517 
518 	if (!(opts & opt_y))
519 		confirm_action(bus_addr, mode, data_addr, pec);
520 
521 	if (pec)
522 		i2c_set_pec(fd, 1);
523 
524 	switch (mode) {
525 	case I2C_SMBUS_BYTE:
526 		if (data_addr >= 0) {
527 			status = i2c_smbus_write_byte(fd, data_addr);
528 			if (status < 0)
529 				bb_simple_error_msg("warning - write failed");
530 		}
531 		status = i2c_smbus_read_byte(fd);
532 		break;
533 	case I2C_SMBUS_WORD_DATA:
534 		status = i2c_smbus_read_word_data(fd, data_addr);
535 		break;
536 	default: /* I2C_SMBUS_BYTE_DATA */
537 		status = i2c_smbus_read_byte_data(fd, data_addr);
538 	}
539 	close(fd);
540 
541 	if (status < 0)
542 		bb_simple_perror_msg_and_die("read failed");
543 
544 	printf("0x%0*x\n", mode == I2C_SMBUS_WORD_DATA ? 4 : 2, status);
545 
546 	return 0;
547 }
548 #endif /* ENABLE_I2CGET */
549 
550 #if ENABLE_I2CSET
551 //usage:#define i2cset_trivial_usage
552 //usage:       "[-fy] [-m MASK] BUS CHIP-ADDRESS DATA-ADDRESS [VALUE] ... [MODE]"
553 //usage:#define i2cset_full_usage "\n\n"
554 //usage:       "Set I2C registers"
555 //usage:     "\n"
556 //usage:     "\n	I2CBUS	I2C bus number"
557 //usage:     "\n	ADDRESS	0x03-0x77"
558 //usage:     "\nMODE is:"
559 //usage:     "\n	c	Byte, no value"
560 //usage:     "\n	b	Byte data (default)"
561 //usage:     "\n	w	Word data"
562 //usage:     "\n	i	I2C block data"
563 //usage:     "\n	s	SMBus block data"
564 //usage:     "\n	Append p for SMBus PEC"
565 //usage:     "\n"
566 //usage:     "\n	-f	Force access"
567 //usage:     "\n	-y	Disable interactive mode"
568 //usage:     "\n	-r	Read back and compare the result"
569 //usage:     "\n	-m MASK	Mask specifying which bits to write"
570 int i2cset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
i2cset_main(int argc,char ** argv)571 int i2cset_main(int argc, char **argv)
572 {
573 	const unsigned opt_f = (1 << 0), opt_y = (1 << 1),
574 			      opt_m = (1 << 2), opt_r = (1 << 3);
575 
576 	int bus_num, bus_addr, data_addr, mode = I2C_SMBUS_BYTE, pec = 0;
577 	int val, blen, mask, fd, status;
578 	unsigned char block[I2C_SMBUS_BLOCK_MAX];
579 	char *opt_m_arg = NULL;
580 	unsigned opts;
581 
582 	opts = getopt32(argv, "^"
583 		"fym:r"
584 		"\0" "-3", /* minimum 3 args */
585 		&opt_m_arg
586 	);
587 	argv += optind;
588 	argc -= optind;
589 	argc--; /* now argv[argc] is last arg */
590 
591 	bus_num = i2c_bus_lookup(argv[0]);
592 	bus_addr = i2c_parse_bus_addr(argv[1]);
593 	data_addr = i2c_parse_data_addr(argv[2]);
594 
595 	if (argv[3]) {
596 		if (!argv[4] && argv[3][0] != 'c') {
597 			mode = I2C_SMBUS_BYTE_DATA; /* Implicit b */
598 		} else {
599 			switch (argv[argc][0]) {
600 			case 'c': /* Already set */
601 				break;
602 			case 'b': mode = I2C_SMBUS_BYTE_DATA;
603 				break;
604 			case 'w': mode = I2C_SMBUS_WORD_DATA;
605 				break;
606 			case 's': mode = I2C_SMBUS_BLOCK_DATA;
607 				break;
608 			case 'i': mode = I2C_SMBUS_I2C_BLOCK_DATA;
609 				break;
610 			default:
611 				bb_simple_error_msg("invalid mode");
612 				bb_show_usage();
613 			}
614 
615 			pec = (argv[argc][1] == 'p');
616 			if (mode == I2C_SMBUS_BLOCK_DATA
617 			 || mode == I2C_SMBUS_I2C_BLOCK_DATA
618 			) {
619 				if (pec && mode == I2C_SMBUS_I2C_BLOCK_DATA)
620 					bb_simple_error_msg_and_die(
621 						"PEC not supported for I2C "
622 						"block writes");
623 				if (opts & opt_m)
624 					bb_simple_error_msg_and_die(
625 						"mask not supported for block "
626 						"writes");
627 			}
628 		}
629 	}
630 
631 	/* Prepare the value(s) to be written according to current mode. */
632 	mask = 0;
633 	blen = 0;
634 	switch (mode) {
635 	case I2C_SMBUS_BYTE_DATA:
636 		val = xstrtou_range(argv[3], 0, 0, 0xff);
637 		break;
638 	case I2C_SMBUS_WORD_DATA:
639 		val = xstrtou_range(argv[3], 0, 0, 0xffff);
640 		break;
641 	case I2C_SMBUS_BLOCK_DATA:
642 	case I2C_SMBUS_I2C_BLOCK_DATA:
643 		for (blen = 3; blen < argc; blen++)
644 			block[blen - 3] = xstrtou_range(argv[blen], 0, 0, 0xff);
645 		blen -= 3;
646 		val = -1;
647 		break;
648 	default:
649 		val = -1;
650 		break;
651 	}
652 
653 	if (opts & opt_m) {
654 		mask = xstrtou_range(opt_m_arg, 0, 0,
655 				(mode == I2C_SMBUS_BYTE ||
656 				 mode == I2C_SMBUS_BYTE_DATA) ? 0xff : 0xffff);
657 	}
658 
659 	fd = i2c_dev_open(bus_num);
660 	check_write_funcs(fd, mode, pec);
661 	i2c_set_slave_addr(fd, bus_addr, opts & opt_f);
662 
663 	if (!(opts & opt_y))
664 		confirm_action(bus_addr, mode, data_addr, pec);
665 
666 	/*
667 	 * If we're using mask - read the current value here and adjust the
668 	 * value to be written.
669 	 */
670 	if (opts & opt_m) {
671 		int tmpval;
672 
673 		switch (mode) {
674 		case I2C_SMBUS_BYTE:
675 			tmpval = i2c_smbus_read_byte(fd);
676 			break;
677 		case I2C_SMBUS_WORD_DATA:
678 			tmpval = i2c_smbus_read_word_data(fd, data_addr);
679 			break;
680 		default:
681 			tmpval = i2c_smbus_read_byte_data(fd, data_addr);
682 		}
683 
684 		if (tmpval < 0)
685 			bb_simple_perror_msg_and_die("can't read old value");
686 
687 		val = (val & mask) | (tmpval & ~mask);
688 
689 		if (!(opts & opt_y)) {
690 			bb_error_msg("old value 0x%0*x, write mask "
691 				"0x%0*x, will write 0x%0*x to register "
692 				"0x%02x",
693 				mode == I2C_SMBUS_WORD_DATA ? 4 : 2, tmpval,
694 				mode == I2C_SMBUS_WORD_DATA ? 4 : 2, mask,
695 				mode == I2C_SMBUS_WORD_DATA ? 4 : 2, val,
696 				data_addr);
697 			confirm_or_abort();
698 		}
699 	}
700 
701 	if (pec)
702 		i2c_set_pec(fd, 1);
703 
704 	switch (mode) {
705 	case I2C_SMBUS_BYTE:
706 		status = i2c_smbus_write_byte(fd, data_addr);
707 		break;
708 	case I2C_SMBUS_WORD_DATA:
709 		status = i2c_smbus_write_word_data(fd, data_addr, val);
710 		break;
711 	case I2C_SMBUS_BLOCK_DATA:
712 		status = i2c_smbus_write_block_data(fd, data_addr,
713 						    blen, block);
714 		break;
715 	case I2C_SMBUS_I2C_BLOCK_DATA:
716 		status = i2c_smbus_write_i2c_block_data(fd, data_addr,
717 							blen, block);
718 		break;
719 	default: /* I2C_SMBUS_BYTE_DATA */
720 		status = i2c_smbus_write_byte_data(fd, data_addr, val);
721 		break;
722 	}
723 	if (status < 0)
724 		bb_simple_perror_msg_and_die("write failed");
725 
726 	if (pec)
727 		i2c_set_pec(fd, 0); /* Clear PEC. */
728 
729 	/* No readback required - we're done. */
730 	if (!(opts & opt_r))
731 		return 0;
732 
733 	switch (mode) {
734 	case I2C_SMBUS_BYTE:
735 		status = i2c_smbus_read_byte(fd);
736 		val = data_addr;
737 		break;
738 	case I2C_SMBUS_WORD_DATA:
739 		status = i2c_smbus_read_word_data(fd, data_addr);
740 		break;
741 	default: /* I2C_SMBUS_BYTE_DATA */
742 		status = i2c_smbus_read_byte_data(fd, data_addr);
743 	}
744 
745 	if (status < 0) {
746 		puts("Warning - readback failed");
747 	} else
748 	if (status != val) {
749 		printf("Warning - data mismatch - wrote "
750 		       "0x%0*x, read back 0x%0*x\n",
751 		       mode == I2C_SMBUS_WORD_DATA ? 4 : 2, val,
752 		       mode == I2C_SMBUS_WORD_DATA ? 4 : 2, status);
753 	} else {
754 		printf("Value 0x%0*x written, readback matched\n",
755 		       mode == I2C_SMBUS_WORD_DATA ? 4 : 2, val);
756 	}
757 
758 	return 0;
759 }
760 #endif /* ENABLE_I2CSET */
761 
762 #if ENABLE_I2CDUMP
read_block_data(int buf_fd,int mode,int * block)763 static int read_block_data(int buf_fd, int mode, int *block)
764 {
765 	uint8_t cblock[I2C_SMBUS_BLOCK_MAX + I2CDUMP_NUM_REGS];
766 	int res, blen = 0, tmp, i;
767 
768 	if (mode == I2C_SMBUS_BLOCK_DATA) {
769 		blen = i2c_smbus_read_block_data(buf_fd, 0, cblock);
770 		if (blen <= 0)
771 			goto fail;
772 	} else {
773 		for (res = 0; res < I2CDUMP_NUM_REGS; res += tmp) {
774 			tmp = i2c_smbus_read_i2c_block_data(
775 					buf_fd, res, I2C_SMBUS_BLOCK_MAX,
776 					cblock + res);
777 			if (tmp <= 0) {
778 				blen = tmp;
779 				goto fail;
780 			}
781 		}
782 
783 		if (res >= I2CDUMP_NUM_REGS)
784 			res = I2CDUMP_NUM_REGS;
785 
786 		for (i = 0; i < res; i++)
787 			block[i] = cblock[i];
788 
789 		if (mode != I2C_SMBUS_BLOCK_DATA)
790 			for (i = res; i < I2CDUMP_NUM_REGS; i++)
791 				block[i] = -1;
792 	}
793 
794 	return blen;
795 
796  fail:
797 	bb_error_msg_and_die("block read failed: %d", blen);
798 }
799 
800 /* Dump all but word data. */
dump_data(int bus_fd,int mode,unsigned first,unsigned last,int * block,int blen)801 static void dump_data(int bus_fd, int mode, unsigned first,
802 		      unsigned last, int *block, int blen)
803 {
804 	int i, j, res;
805 
806 	puts("     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f"
807 	     "    0123456789abcdef");
808 
809 	for (i = 0; i < I2CDUMP_NUM_REGS; i += 0x10) {
810 		if (mode == I2C_SMBUS_BLOCK_DATA && i >= blen)
811 			break;
812 		if (i/16 < first/16)
813 			continue;
814 		if (i/16 > last/16)
815 			break;
816 
817 		printf("%02x: ", i);
818 		for (j = 0; j < 16; j++) {
819 			fflush_all();
820 			/* Skip unwanted registers */
821 			if (i+j < first || i+j > last) {
822 				printf("   ");
823 				if (mode == I2C_SMBUS_WORD_DATA) {
824 					printf("   ");
825 					j++;
826 				}
827 				continue;
828 			}
829 
830 			switch (mode) {
831 			case I2C_SMBUS_BYTE_DATA:
832 				res = i2c_smbus_read_byte_data(bus_fd, i+j);
833 				block[i+j] = res;
834 				break;
835 			case I2C_SMBUS_WORD_DATA:
836 				res = i2c_smbus_read_word_data(bus_fd, i+j);
837 				if (res < 0) {
838 					block[i+j] = res;
839 					block[i+j+1] = res;
840 				} else {
841 					block[i+j] = res & 0xff;
842 					block[i+j+1] = res >> 8;
843 				}
844 				break;
845 			case I2C_SMBUS_BYTE:
846 				res = i2c_smbus_read_byte(bus_fd);
847 				block[i+j] = res;
848 				break;
849 			default:
850 				res = block[i+j];
851 			}
852 
853 			if (mode == I2C_SMBUS_BLOCK_DATA &&
854 			    i+j >= blen) {
855 				printf("   ");
856 			} else if (res < 0) {
857 				printf("XX ");
858 				if (mode == I2C_SMBUS_WORD_DATA)
859 					printf("XX ");
860 			} else {
861 				printf("%02x ", block[i+j]);
862 				if (mode == I2C_SMBUS_WORD_DATA)
863 					printf("%02x ", block[i+j+1]);
864 			}
865 
866 			if (mode == I2C_SMBUS_WORD_DATA)
867 				j++;
868 		}
869 		printf("   ");
870 
871 		for (j = 0; j < 16; j++) {
872 			if (mode == I2C_SMBUS_BLOCK_DATA && i+j >= blen)
873 				break;
874 			/* Skip unwanted registers */
875 			if (i+j < first || i+j > last) {
876 				bb_putchar(' ');
877 				continue;
878 			}
879 
880 			res = block[i+j];
881 			if (res < 0) {
882 				bb_putchar('X');
883 			} else if (res == 0x00 || res == 0xff) {
884 				bb_putchar('.');
885 			} else if (res < 32 || res >= 127) {
886 				bb_putchar('?');
887 			} else {
888 				bb_putchar(res);
889 			}
890 		}
891 		bb_putchar('\n');
892 	}
893 }
894 
dump_word_data(int bus_fd,unsigned first,unsigned last)895 static void dump_word_data(int bus_fd, unsigned first, unsigned last)
896 {
897 	int i, j, rv;
898 
899 	/* Word data. */
900 	puts("     0,8  1,9  2,a  3,b  4,c  5,d  6,e  7,f");
901 	for (i = 0; i < 256; i += 8) {
902 		if (i/8 < first/8)
903 			continue;
904 		if (i/8 > last/8)
905 			break;
906 
907 		printf("%02x: ", i);
908 		for (j = 0; j < 8; j++) {
909 			/* Skip unwanted registers. */
910 			if (i+j < first || i+j > last) {
911 				printf("     ");
912 				continue;
913 			}
914 
915 			rv = i2c_smbus_read_word_data(bus_fd, i+j);
916 			if (rv < 0)
917 				printf("XXXX ");
918 			else
919 				printf("%04x ", rv & 0xffff);
920 		}
921 		bb_putchar('\n');
922 	}
923 }
924 
925 //usage:#define i2cdump_trivial_usage
926 //usage:       "[-fy] [-r FIRST-LAST] BUS ADDR [MODE]"
927 //usage:#define i2cdump_full_usage "\n\n"
928 //usage:       "Examine I2C registers"
929 //usage:     "\n"
930 //usage:     "\n	I2CBUS	I2C bus number"
931 //usage:     "\n	ADDRESS	0x03-0x77"
932 //usage:     "\nMODE is:"
933 //usage:     "\n	b	Byte (default)"
934 //usage:     "\n	w	Word"
935 //usage:     "\n	W	Word on even register addresses"
936 //usage:     "\n	i	I2C block"
937 //usage:     "\n	s	SMBus block"
938 //usage:     "\n	c	Consecutive byte"
939 //usage:     "\n	Append p for SMBus PEC"
940 //usage:     "\n"
941 //usage:     "\n	-f	Force access"
942 //usage:     "\n	-y	Disable interactive mode"
943 //usage:     "\n	-r	Limit the number of registers being accessed"
944 int i2cdump_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
i2cdump_main(int argc UNUSED_PARAM,char ** argv)945 int i2cdump_main(int argc UNUSED_PARAM, char **argv)
946 {
947 	const unsigned opt_f = (1 << 0), opt_y = (1 << 1),
948 			      opt_r = (1 << 2);
949 
950 	int bus_num, bus_addr, mode = I2C_SMBUS_BYTE_DATA, even = 0, pec = 0;
951 	unsigned first = 0x00, last = 0xff, opts;
952 	int block[I2CDUMP_NUM_REGS];
953 	char *opt_r_str, *dash;
954 	int fd, res;
955 
956 	opts = getopt32(argv, "^"
957 		"fyr:"
958 		"\0" "-2:?3" /* from 2 to 3 args */,
959 		&opt_r_str
960 	);
961 	argv += optind;
962 
963 	bus_num = i2c_bus_lookup(argv[0]);
964 	bus_addr = i2c_parse_bus_addr(argv[1]);
965 
966 	if (argv[2]) {
967 		switch (argv[2][0]) {
968 		case 'b': /* Already set. */			break;
969 		case 'c': mode = I2C_SMBUS_BYTE;		break;
970 		case 'w': mode = I2C_SMBUS_WORD_DATA;		break;
971 		case 'W':
972 			mode = I2C_SMBUS_WORD_DATA;
973 			even = 1;
974 			break;
975 		case 's': mode = I2C_SMBUS_BLOCK_DATA;		break;
976 		case 'i': mode = I2C_SMBUS_I2C_BLOCK_DATA;	break;
977 		default:
978 			bb_simple_error_msg_and_die("invalid mode");
979 		}
980 
981 		if (argv[2][1] == 'p') {
982 			if (argv[2][0] == 'W' || argv[2][0] == 'i') {
983 				bb_simple_error_msg_and_die(
984 					"pec not supported for -W and -i");
985 			} else {
986 				pec = 1;
987 			}
988 		}
989 	}
990 
991 	if (opts & opt_r) {
992 		first = strtol(opt_r_str, &dash, 0);
993 		if (dash == opt_r_str || *dash != '-' || first > 0xff)
994 			bb_simple_error_msg_and_die("invalid range");
995 		last = xstrtou_range(++dash, 0, first, 0xff);
996 
997 		/* Range is not available for every mode. */
998 		switch (mode) {
999 		case I2C_SMBUS_BYTE:
1000 		case I2C_SMBUS_BYTE_DATA:
1001 			break;
1002 		case I2C_SMBUS_WORD_DATA:
1003 			if (!even || (!(first % 2) && last % 2))
1004 				break;
1005 			/* Fall through */
1006 		default:
1007 			bb_simple_error_msg_and_die(
1008 				"range not compatible with selected mode");
1009 		}
1010 	}
1011 
1012 	fd = i2c_dev_open(bus_num);
1013 	check_read_funcs(fd, mode, -1 /* data_addr */, pec);
1014 	i2c_set_slave_addr(fd, bus_addr, opts & opt_f);
1015 
1016 	if (pec)
1017 		i2c_set_pec(fd, 1);
1018 
1019 	if (!(opts & opt_y))
1020 		confirm_action(bus_addr, mode, -1 /* data_addr */, pec);
1021 
1022 	/* All but word data. */
1023 	if (mode != I2C_SMBUS_WORD_DATA || even) {
1024 		int blen = 0;
1025 
1026 		if (mode == I2C_SMBUS_BLOCK_DATA || mode == I2C_SMBUS_I2C_BLOCK_DATA)
1027 			blen = read_block_data(fd, mode, block);
1028 
1029 		if (mode == I2C_SMBUS_BYTE) {
1030 			res = i2c_smbus_write_byte(fd, first);
1031 			if (res < 0)
1032 				bb_simple_perror_msg_and_die("write start address");
1033 		}
1034 
1035 		dump_data(fd, mode, first, last, block, blen);
1036 	} else {
1037 		dump_word_data(fd, first, last);
1038 	}
1039 
1040 	return 0;
1041 }
1042 #endif /* ENABLE_I2CDUMP */
1043 
1044 #if ENABLE_I2CDETECT
1045 enum adapter_type {
1046 	ADT_DUMMY = 0,
1047 	ADT_ISA,
1048 	ADT_I2C,
1049 	ADT_SMBUS,
1050 };
1051 
1052 struct adap_desc {
1053 	const char *funcs;
1054 	const char *algo;
1055 };
1056 
1057 static const struct adap_desc adap_descs[] ALIGN_PTR = {
1058 	{ .funcs = "dummy", .algo = "Dummy bus", },
1059 	{ .funcs = "isa",   .algo = "ISA bus", },
1060 	{ .funcs = "i2c",   .algo = "I2C adapter", },
1061 	{ .funcs = "smbus", .algo = "SMBus adapter", },
1062 };
1063 
1064 struct i2c_func {
1065 	long value;
1066 	const char* name;
1067 };
1068 
1069 static const struct i2c_func i2c_funcs_tab[] ALIGN_PTR = {
1070 	{ .value = I2C_FUNC_I2C,
1071 	  .name = "I2C" },
1072 	{ .value = I2C_FUNC_SMBUS_QUICK,
1073 	  .name = "SMBus quick command" },
1074 	{ .value = I2C_FUNC_SMBUS_WRITE_BYTE,
1075 	  .name = "SMBus send byte" },
1076 	{ .value = I2C_FUNC_SMBUS_READ_BYTE,
1077 	  .name = "SMBus receive byte" },
1078 	{ .value = I2C_FUNC_SMBUS_WRITE_BYTE_DATA,
1079 	  .name = "SMBus write byte" },
1080 	{ .value = I2C_FUNC_SMBUS_READ_BYTE_DATA,
1081 	  .name = "SMBus read byte" },
1082 	{ .value = I2C_FUNC_SMBUS_WRITE_WORD_DATA,
1083 	  .name = "SMBus write word" },
1084 	{ .value = I2C_FUNC_SMBUS_READ_WORD_DATA,
1085 	  .name = "SMBus read word" },
1086 	{ .value = I2C_FUNC_SMBUS_PROC_CALL,
1087 	  .name = "SMBus process call" },
1088 	{ .value = I2C_FUNC_SMBUS_WRITE_BLOCK_DATA,
1089 	  .name = "SMBus block write" },
1090 	{ .value = I2C_FUNC_SMBUS_READ_BLOCK_DATA,
1091 	  .name = "SMBus block read" },
1092 	{ .value = I2C_FUNC_SMBUS_BLOCK_PROC_CALL,
1093 	  .name = "SMBus block process call" },
1094 	{ .value = I2C_FUNC_SMBUS_PEC,
1095 	  .name = "SMBus PEC" },
1096 	{ .value = I2C_FUNC_SMBUS_WRITE_I2C_BLOCK,
1097 	  .name = "I2C block write" },
1098 	{ .value = I2C_FUNC_SMBUS_READ_I2C_BLOCK,
1099 	  .name = "I2C block read" },
1100 	{ .value = 0, .name = NULL }
1101 };
1102 
i2cdetect_get_funcs(int bus)1103 static enum adapter_type i2cdetect_get_funcs(int bus)
1104 {
1105 	enum adapter_type ret;
1106 	unsigned long funcs;
1107 	int fd;
1108 
1109 	fd = i2c_dev_open(bus);
1110 
1111 	get_funcs_matrix(fd, &funcs);
1112 	if (funcs & I2C_FUNC_I2C)
1113 		ret = ADT_I2C;
1114 	else if (funcs & (I2C_FUNC_SMBUS_BYTE |
1115 			  I2C_FUNC_SMBUS_BYTE_DATA |
1116 			  I2C_FUNC_SMBUS_WORD_DATA))
1117 		ret = ADT_SMBUS;
1118 	else
1119 		ret = ADT_DUMMY;
1120 
1121 	close(fd);
1122 
1123 	return ret;
1124 }
1125 
list_i2c_busses_and_exit(void)1126 static void NORETURN list_i2c_busses_and_exit(void)
1127 {
1128 	const char *const i2cdev_path = "/sys/class/i2c-dev";
1129 
1130 	char path[NAME_MAX], name[128];
1131 	struct dirent *de, *subde;
1132 	enum adapter_type adt;
1133 	DIR *dir, *subdir;
1134 	int rv, bus;
1135 	char *pos;
1136 	FILE *fp;
1137 
1138 	/*
1139 	 * XXX Upstream i2cdetect also looks for i2c bus info in /proc/bus/i2c,
1140 	 * but we won't bother since it's only useful on older kernels (before
1141 	 * 2.6.5). We expect sysfs to be present and mounted at /sys/.
1142 	 */
1143 
1144 	dir = xopendir(i2cdev_path);
1145 	while ((de = readdir(dir))) {
1146 		if (de->d_name[0] == '.')
1147 			continue;
1148 
1149 		/* Simple version for ISA chips. */
1150 		snprintf(path, NAME_MAX, "%s/%s/name",
1151 			 i2cdev_path, de->d_name);
1152 		fp = fopen_for_read(path);
1153 		if (fp == NULL) {
1154 			snprintf(path, NAME_MAX,
1155 				 "%s/%s/device/name",
1156 				 i2cdev_path, de->d_name);
1157 			fp = fopen_for_read(path);
1158 		}
1159 
1160 		/* Non-ISA chips require the hard-way. */
1161 		if (fp == NULL) {
1162 			snprintf(path, NAME_MAX,
1163 				 "%s/%s/device/name",
1164 				 i2cdev_path, de->d_name);
1165 			subdir = opendir(path);
1166 			if (subdir == NULL)
1167 				continue;
1168 
1169 			while ((subde = readdir(subdir))) {
1170 				if (subde->d_name[0] == '.')
1171 					continue;
1172 
1173 				if (is_prefixed_with(subde->d_name, "i2c-")) {
1174 					snprintf(path, NAME_MAX,
1175 						 "%s/%s/device/%s/name",
1176 						 i2cdev_path, de->d_name,
1177 						 subde->d_name);
1178 					fp = fopen_for_read(path);
1179 					break;
1180 				}
1181 			}
1182 		}
1183 
1184 		if (fp != NULL) {
1185 			/*
1186 			 * Get the rest of the info and display a line
1187 			 * for a single bus.
1188 			 */
1189 			memset(name, 0, sizeof(name));
1190 			pos = fgets(name, sizeof(name), fp);
1191 			fclose(fp);
1192 			if (pos == NULL)
1193 				continue;
1194 
1195 			pos = strchr(name, '\n');
1196 			if (pos != NULL)
1197 				*pos = '\0';
1198 
1199 			rv = sscanf(de->d_name, "i2c-%d", &bus);
1200 			if (rv != 1)
1201 				continue;
1202 
1203 			if (is_prefixed_with(name, "ISA"))
1204 				adt = ADT_ISA;
1205 			else
1206 				adt = i2cdetect_get_funcs(bus);
1207 
1208 			printf(
1209 				"i2c-%d\t%-10s\t%-32s\t%s\n",
1210 				bus, adap_descs[adt].funcs,
1211 				name, adap_descs[adt].algo);
1212 		}
1213 	}
1214 
1215 	exit(EXIT_SUCCESS);
1216 }
1217 
no_support(const char * cmd)1218 static void NORETURN no_support(const char *cmd)
1219 {
1220 	bb_error_msg_and_die("bus doesn't support %s", cmd);
1221 }
1222 
will_skip(const char * cmd)1223 static void will_skip(const char *cmd)
1224 {
1225 	bb_error_msg(
1226 		"warning: can't use %s command, "
1227 		"will skip some addresses", cmd);
1228 }
1229 
1230 //usage:#define i2cdetect_trivial_usage
1231 //usage:       "-l | -F I2CBUS | [-ya] [-q|-r] I2CBUS [FIRST LAST]"
1232 //usage:#define i2cdetect_full_usage "\n\n"
1233 //usage:       "Detect I2C chips"
1234 //usage:     "\n"
1235 //usage:     "\n	-l	List installed buses"
1236 //usage:     "\n	-F BUS#	List functionalities on this bus"
1237 //usage:     "\n	-y	Disable interactive mode"
1238 //usage:     "\n	-a	Force scanning of non-regular addresses"
1239 //usage:     "\n	-q	Use smbus quick write commands for probing (default)"
1240 //usage:     "\n	-r	Use smbus read byte commands for probing"
1241 //usage:     "\n	FIRST and LAST limit probing range"
1242 int i2cdetect_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
i2cdetect_main(int argc UNUSED_PARAM,char ** argv)1243 int i2cdetect_main(int argc UNUSED_PARAM, char **argv)
1244 {
1245 	const unsigned opt_y = (1 << 0), opt_a = (1 << 1),
1246 			      opt_q = (1 << 2), opt_r = (1 << 3),
1247 			      opt_F = (1 << 4), opt_l = (1 << 5);
1248 
1249 	int fd, bus_num, i, j, mode = I2CDETECT_MODE_AUTO, status, cmd;
1250 	unsigned first = 0x03, last = 0x77, opts;
1251 	unsigned long funcs;
1252 
1253 	opts = getopt32(argv, "^"
1254 			"yaqrFl"
1255 			"\0"
1256 			"q--r:r--q:"/*mutually exclusive*/
1257 			"?3"/*up to 3 args*/
1258 	);
1259 	argv += optind;
1260 
1261 	if (opts & opt_l)
1262 		list_i2c_busses_and_exit();
1263 
1264 	if (!argv[0])
1265 		bb_show_usage();
1266 
1267 	bus_num = i2c_bus_lookup(argv[0]);
1268 	fd = i2c_dev_open(bus_num);
1269 	get_funcs_matrix(fd, &funcs);
1270 
1271 	if (opts & opt_F) {
1272 		/* Only list the functionalities. */
1273 		printf("Functionalities implemented by bus #%d\n", bus_num);
1274 		for (i = 0; i2c_funcs_tab[i].value; i++) {
1275 			printf("%-32s %s\n", i2c_funcs_tab[i].name,
1276 			       funcs & i2c_funcs_tab[i].value ? "yes" : "no");
1277 		}
1278 
1279 		return EXIT_SUCCESS;
1280 	}
1281 
1282 	if (opts & opt_r)
1283 		mode = I2CDETECT_MODE_READ;
1284 	else if (opts & opt_q)
1285 		mode = I2CDETECT_MODE_QUICK;
1286 
1287 	if (opts & opt_a) {
1288 		first = 0x00;
1289 		last = 0x7f;
1290 	}
1291 
1292 	/* Read address range. */
1293 	if (argv[1]) {
1294 		first = xstrtou_range(argv[1], 16, first, last);
1295 		if (argv[2])
1296 			last = xstrtou_range(argv[2], 16, first, last);
1297 	}
1298 
1299 	if (!(funcs & (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_READ_BYTE))) {
1300 		no_support("detection commands");
1301 	} else
1302 	if (mode == I2CDETECT_MODE_QUICK && !(funcs & I2C_FUNC_SMBUS_QUICK)) {
1303 		no_support("SMBus quick write");
1304 	} else
1305 	if (mode == I2CDETECT_MODE_READ && !(funcs & I2C_FUNC_SMBUS_READ_BYTE)) {
1306 		no_support("SMBus receive byte");
1307 	}
1308 
1309 	if (mode == I2CDETECT_MODE_AUTO) {
1310 		if (!(funcs & I2C_FUNC_SMBUS_QUICK))
1311 			will_skip("SMBus quick write");
1312 		if (!(funcs & I2C_FUNC_SMBUS_READ_BYTE))
1313 			will_skip("SMBus receive byte");
1314 	}
1315 
1316 	if (!(opts & opt_y))
1317 		confirm_action(-1, -1, -1, 0);
1318 
1319 	puts("     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f");
1320 	for (i = 0; i < 128; i += 16) {
1321 		printf("%02x: ", i);
1322 		for (j = 0; j < 16; j++) {
1323 			fflush_all();
1324 
1325 			cmd = mode;
1326 			if (mode == I2CDETECT_MODE_AUTO) {
1327 				if ((i+j >= 0x30 && i+j <= 0x37) ||
1328 				    (i+j >= 0x50 && i+j <= 0x5F))
1329 					cmd = I2CDETECT_MODE_READ;
1330 				else
1331 					cmd = I2CDETECT_MODE_QUICK;
1332 			}
1333 
1334 			/* Skip unwanted addresses. */
1335 			if (i+j < first
1336 			 || i+j > last
1337 			 || (cmd == I2CDETECT_MODE_READ && !(funcs & I2C_FUNC_SMBUS_READ_BYTE))
1338 			 || (cmd == I2CDETECT_MODE_QUICK && !(funcs & I2C_FUNC_SMBUS_QUICK)))
1339 			{
1340 				printf("   ");
1341 				continue;
1342 			}
1343 
1344 			status = ioctl(fd, I2C_SLAVE, itoptr(i + j));
1345 			if (status < 0) {
1346 				if (errno == EBUSY) {
1347 					printf("UU ");
1348 					continue;
1349 				}
1350 
1351 				bb_perror_msg_and_die(
1352 					"can't set address to 0x%02x", i + j);
1353 			}
1354 
1355 			switch (cmd) {
1356 			case I2CDETECT_MODE_READ:
1357 				/*
1358 				 * This is known to lock SMBus on various
1359 				 * write-only chips (mainly clock chips).
1360 				 */
1361 				status = i2c_smbus_read_byte(fd);
1362 				break;
1363 			default: /* I2CDETECT_MODE_QUICK: */
1364 				/*
1365 				 * This is known to corrupt the Atmel
1366 				 * AT24RF08 EEPROM.
1367 				 */
1368 				status = i2c_smbus_write_quick(fd,
1369 							       I2C_SMBUS_WRITE);
1370 				break;
1371 			}
1372 
1373 			if (status < 0)
1374 				printf("-- ");
1375 			else
1376 				printf("%02x ", i+j);
1377 		}
1378 		bb_putchar('\n');
1379 	}
1380 
1381 	return 0;
1382 }
1383 #endif /* ENABLE_I2CDETECT */
1384 
1385 #if ENABLE_I2CTRANSFER
check_i2c_func(int fd)1386 static void check_i2c_func(int fd)
1387 {
1388 	unsigned long funcs;
1389 
1390 	get_funcs_matrix(fd, &funcs);
1391 
1392 	if (!(funcs & I2C_FUNC_I2C))
1393 		bb_simple_error_msg_and_die("adapter does not support I2C transfers");
1394 }
1395 
1396 //usage:#define i2ctransfer_trivial_usage
1397 //usage:       "[-fay] I2CBUS { rLENGTH[@ADDR] | wLENGTH[@ADDR] DATA...}..."
1398 //usage:#define i2ctransfer_full_usage "\n\n"
1399 //usage:       "Read/write I2C data in one transfer"
1400 //usage:     "\n"
1401 //usage:     "\n	-f	Force access to busy addresses"
1402 //usage:     "\n	-a	Force access to non-regular addresses"
1403 //usage:     "\n	-y	Disable interactive mode"
1404 int i2ctransfer_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
i2ctransfer_main(int argc UNUSED_PARAM,char ** argv)1405 int i2ctransfer_main(int argc UNUSED_PARAM, char **argv)
1406 {
1407 	enum {
1408 		opt_f = (1 << 0),
1409 		opt_y = (1 << 1),
1410 		opt_a = (1 << 2),
1411 	};
1412 	int bus_num, bus_addr;
1413 	int fd;
1414 	unsigned opts, first, last;
1415 	int nmsgs, nmsgs_sent, i;
1416 	struct i2c_msg msgs[I2C_RDWR_IOCTL_MAX_MSGS];
1417 	struct i2c_rdwr_ioctl_data rdwr;
1418 
1419 	memset(msgs, 0, sizeof(msgs));
1420 
1421 	opts = getopt32(argv, "^"
1422 		"fya"
1423 		"\0" "-2" /* minimum 2 args */
1424 	);
1425 	first = 0x03;
1426 	last = 0x77;
1427 	if (opts & opt_a) {
1428 		first = 0x00;
1429 		last = 0x7f;
1430 	}
1431 
1432 	argv += optind;
1433 	bus_num = i2c_bus_lookup(argv[0]);
1434 	fd = i2c_dev_open(bus_num);
1435 	check_i2c_func(fd);
1436 
1437 	bus_addr = -1;
1438 	nmsgs = 0;
1439 	while (*++argv) {
1440 		char *arg_ptr;
1441 		unsigned len;
1442 		uint16_t flags;
1443 		char *end;
1444 
1445 		if (nmsgs >= I2C_RDWR_IOCTL_MAX_MSGS)
1446 			bb_simple_error_msg_and_die("too many messages, max: "I2C_RDWR_IOCTL_MAX_MSGS_STR);
1447 
1448 		flags = 0;
1449 		arg_ptr = *argv;
1450 		switch (*arg_ptr++) {
1451 		case 'r': flags |= I2C_M_RD; break;
1452 		case 'w': break;
1453 		default:
1454 			bb_show_usage();
1455 		}
1456 
1457 		end = strchr(arg_ptr, '@');
1458 		if (end) *end = '\0';
1459 		len = xstrtou_range(arg_ptr, 0, 0, 0xffff);
1460 		if (end) {
1461 			bus_addr = xstrtou_range(end + 1, 0, first, last);
1462 			i2c_set_slave_addr(fd, bus_addr, (opts & opt_f));
1463 		} else {
1464 			/* Reuse last address if possible */
1465 			if (bus_addr < 0)
1466 				bb_error_msg_and_die("no address given in '%s'", *argv);
1467 		}
1468 
1469 		msgs[nmsgs].addr = bus_addr;
1470 		msgs[nmsgs].flags = flags;
1471 		msgs[nmsgs].len = len;
1472 		if (len)
1473 			msgs[nmsgs].buf = xzalloc(len);
1474 
1475 		if (!(flags & I2C_M_RD)) {
1476 			/* Consume DATA arg(s) */
1477 			unsigned buf_idx = 0;
1478 
1479 			while (buf_idx < len) {
1480 				uint8_t data8;
1481 				unsigned long data;
1482 
1483 				arg_ptr = *++argv;
1484 				if (!arg_ptr)
1485 					bb_show_usage();
1486 				data = strtoul(arg_ptr, &end, 0);
1487 				if (data > 0xff || arg_ptr == end)
1488 					bb_error_msg_and_die("invalid data byte '%s'", *argv);
1489 
1490 				data8 = data;
1491 				while (buf_idx < len) {
1492 					msgs[nmsgs].buf[buf_idx++] = data8;
1493 					if (!*end)
1494 						break;
1495 					switch (*end) {
1496 					/* Pseudo randomness (8 bit AXR with a=13 and b=27) */
1497 					case 'p':
1498 						data8 = (data8 ^ 27) + 13;
1499 						data8 = (data8 << 1) | (data8 >> 7);
1500 						break;
1501 					case '+': data8++; break;
1502 					case '-': data8--; break;
1503 					case '=': break;
1504 					default:
1505 						bb_error_msg_and_die("invalid data byte suffix: '%s'",
1506 								     *argv);
1507 					}
1508 				}
1509 			}
1510 		}
1511 		nmsgs++;
1512 	}
1513 
1514 	if (!(opts & opt_y))
1515 		confirm_action(bus_addr, 0, 0, 0);
1516 
1517 	rdwr.msgs = msgs;
1518 	rdwr.nmsgs = nmsgs;
1519 	nmsgs_sent = ioctl_or_perror_and_die(fd, I2C_RDWR, &rdwr, "I2C_RDWR");
1520 	if (nmsgs_sent < nmsgs)
1521 		bb_error_msg("warning: only %u/%u messages sent", nmsgs_sent, nmsgs);
1522 
1523 	for (i = 0; i < nmsgs_sent; i++) {
1524 		if (msgs[i].len != 0 && (msgs[i].flags & I2C_M_RD)) {
1525 			int j;
1526 			for (j = 0; j < msgs[i].len - 1; j++)
1527 				printf("0x%02x ", msgs[i].buf[j]);
1528 			/* Print final byte with newline */
1529 			printf("0x%02x\n", msgs[i].buf[j]);
1530 		}
1531 	}
1532 
1533 # if ENABLE_FEATURE_CLEAN_UP
1534 	close(fd);
1535 	for (i = 0; i < nmsgs; i++)
1536 		free(msgs[i].buf);
1537 # endif
1538 
1539 	return 0;
1540 }
1541 #endif /* ENABLE_I2CTRANSFER */
1542