1 /* vi: set sw=4 ts=4: */
3 * Minimal i2c-tools implementation for busybox.
4 * Parts of code ported from i2c-tools:
5 * http://www.lm-sensors.org/wiki/I2CTools.
7 * Copyright (C) 2014 by Bartosz Golaszewski <bartekgola@gmail.com>
9 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
12 //config:config I2CGET
13 //config: bool "i2cget"
15 //config: select PLATFORM_LINUX
17 //config: Read from I2C/SMBus chip registers.
19 //config:config I2CSET
20 //config: bool "i2cset"
22 //config: select PLATFORM_LINUX
24 //config: Set I2C registers.
26 //config:config I2CDUMP
27 //config: bool "i2cdump"
29 //config: select PLATFORM_LINUX
31 //config: Examine I2C registers.
33 //config:config I2CDETECT
34 //config: bool "i2cdetect"
36 //config: select PLATFORM_LINUX
38 //config: Detect I2C chips.
41 //applet:IF_I2CGET(APPLET(i2cget, BB_DIR_USR_SBIN, BB_SUID_DROP))
42 //applet:IF_I2CSET(APPLET(i2cset, BB_DIR_USR_SBIN, BB_SUID_DROP))
43 //applet:IF_I2CDUMP(APPLET(i2cdump, BB_DIR_USR_SBIN, BB_SUID_DROP))
44 //applet:IF_I2CDETECT(APPLET(i2cdetect, BB_DIR_USR_SBIN, BB_SUID_DROP))
46 //kbuild:lib-$(CONFIG_I2CGET) += i2c_tools.o
47 //kbuild:lib-$(CONFIG_I2CSET) += i2c_tools.o
48 //kbuild:lib-$(CONFIG_I2CDUMP) += i2c_tools.o
49 //kbuild:lib-$(CONFIG_I2CDETECT) += i2c_tools.o
54 * - upstream i2c-tools can also look-up i2c busses by name, we only accept
56 * - bank and bankreg parameters for i2cdump are not supported because of
57 * their limited usefulness (see i2cdump manual entry for more info),
58 * - i2cdetect doesn't look for bus info in /proc as it does in upstream, but
59 * it shouldn't be a problem in modern kernels.
63 #include "common_bufsiz.h"
65 #include <linux/i2c.h>
66 #include <linux/i2c-dev.h>
68 #define I2CDUMP_NUM_REGS 256
70 #define I2CDETECT_MODE_AUTO 0
71 #define I2CDETECT_MODE_QUICK 1
72 #define I2CDETECT_MODE_READ 2
75 * This is needed for ioctl_or_perror_and_die() since it only accepts pointers.
77 static ALWAYS_INLINE void *itoptr(int i)
79 return (void*)(intptr_t)i;
82 static int32_t i2c_smbus_access(int fd, char read_write, uint8_t cmd,
83 int size, union i2c_smbus_data *data)
85 struct i2c_smbus_ioctl_data args;
87 args.read_write = read_write;
92 return ioctl(fd, I2C_SMBUS, &args);
95 static int32_t i2c_smbus_read_byte(int fd)
97 union i2c_smbus_data data;
100 err = i2c_smbus_access(fd, I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &data);
107 #if ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP
108 static int32_t i2c_smbus_write_byte(int fd, uint8_t val)
110 return i2c_smbus_access(fd, I2C_SMBUS_WRITE,
111 val, I2C_SMBUS_BYTE, NULL);
114 static int32_t i2c_smbus_read_byte_data(int fd, uint8_t cmd)
116 union i2c_smbus_data data;
119 err = i2c_smbus_access(fd, I2C_SMBUS_READ, cmd,
120 I2C_SMBUS_BYTE_DATA, &data);
127 static int32_t i2c_smbus_read_word_data(int fd, uint8_t cmd)
129 union i2c_smbus_data data;
132 err = i2c_smbus_access(fd, I2C_SMBUS_READ, cmd,
133 I2C_SMBUS_WORD_DATA, &data);
139 #endif /* ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP */
142 static int32_t i2c_smbus_write_byte_data(int file,
143 uint8_t cmd, uint8_t value)
145 union i2c_smbus_data data;
149 return i2c_smbus_access(file, I2C_SMBUS_WRITE, cmd,
150 I2C_SMBUS_BYTE_DATA, &data);
153 static int32_t i2c_smbus_write_word_data(int file, uint8_t cmd, uint16_t value)
155 union i2c_smbus_data data;
159 return i2c_smbus_access(file, I2C_SMBUS_WRITE, cmd,
160 I2C_SMBUS_WORD_DATA, &data);
163 static int32_t i2c_smbus_write_block_data(int file, uint8_t cmd,
164 uint8_t length, const uint8_t *values)
166 union i2c_smbus_data data;
168 if (length > I2C_SMBUS_BLOCK_MAX)
169 length = I2C_SMBUS_BLOCK_MAX;
171 memcpy(data.block+1, values, length);
172 data.block[0] = length;
174 return i2c_smbus_access(file, I2C_SMBUS_WRITE, cmd,
175 I2C_SMBUS_BLOCK_DATA, &data);
178 static int32_t i2c_smbus_write_i2c_block_data(int file, uint8_t cmd,
179 uint8_t length, const uint8_t *values)
181 union i2c_smbus_data data;
183 if (length > I2C_SMBUS_BLOCK_MAX)
184 length = I2C_SMBUS_BLOCK_MAX;
186 memcpy(data.block+1, values, length);
187 data.block[0] = length;
189 return i2c_smbus_access(file, I2C_SMBUS_WRITE, cmd,
190 I2C_SMBUS_I2C_BLOCK_BROKEN, &data);
192 #endif /* ENABLE_I2CSET */
196 * Returns the number of bytes read, vals must hold at
197 * least I2C_SMBUS_BLOCK_MAX bytes.
199 static int32_t i2c_smbus_read_block_data(int fd, uint8_t cmd, uint8_t *vals)
201 union i2c_smbus_data data;
204 err = i2c_smbus_access(fd, I2C_SMBUS_READ, cmd,
205 I2C_SMBUS_BLOCK_DATA, &data);
209 for (i = 1; i <= data.block[0]; i++)
210 *vals++ = data.block[i];
211 return data.block[0];
214 static int32_t i2c_smbus_read_i2c_block_data(int fd, uint8_t cmd,
215 uint8_t len, uint8_t *vals)
217 union i2c_smbus_data data;
220 if (len > I2C_SMBUS_BLOCK_MAX)
221 len = I2C_SMBUS_BLOCK_MAX;
224 err = i2c_smbus_access(fd, I2C_SMBUS_READ, cmd,
225 len == 32 ? I2C_SMBUS_I2C_BLOCK_BROKEN :
226 I2C_SMBUS_I2C_BLOCK_DATA, &data);
230 for (i = 1; i <= data.block[0]; i++)
231 *vals++ = data.block[i];
232 return data.block[0];
234 #endif /* ENABLE_I2CDUMP */
237 static int32_t i2c_smbus_write_quick(int fd, uint8_t val)
239 return i2c_smbus_access(fd, val, 0, I2C_SMBUS_QUICK, NULL);
241 #endif /* ENABLE_I2CDETECT */
243 static int i2c_bus_lookup(const char *bus_str)
245 return xstrtou_range(bus_str, 10, 0, 0xfffff);
248 #if ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP
249 static int i2c_parse_bus_addr(const char *addr_str)
251 /* Slave address must be in range 0x03 - 0x77. */
252 return xstrtou_range(addr_str, 16, 0x03, 0x77);
255 static void i2c_set_pec(int fd, int pec)
257 ioctl_or_perror_and_die(fd, I2C_PEC,
262 static void i2c_set_slave_addr(int fd, int addr, int force)
264 ioctl_or_perror_and_die(fd, force ? I2C_SLAVE_FORCE : I2C_SLAVE,
266 "can't set address to 0x%02x", addr);
268 #endif /* ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP */
270 #if ENABLE_I2CGET || ENABLE_I2CSET
271 static int i2c_parse_data_addr(const char *data_addr)
273 /* Data address must be an 8 bit integer. */
274 return xstrtou_range(data_addr, 16, 0, 0xff);
276 #endif /* ENABLE_I2CGET || ENABLE_I2CSET */
279 * Opens the device file associated with given i2c bus.
281 * Upstream i2c-tools also support opening devices by i2c bus name
282 * but we drop it here for size reduction.
284 static int i2c_dev_open(int i2cbus)
286 char filename[sizeof("/dev/i2c-%d") + sizeof(int)*3];
289 sprintf(filename, "/dev/i2c-%d", i2cbus);
290 fd = open(filename, O_RDWR);
292 if (errno == ENOENT) {
293 filename[8] = '/'; /* change to "/dev/i2c/%d" */
294 fd = xopen(filename, O_RDWR);
296 bb_perror_msg_and_die("can't open '%s'", filename);
303 /* Size reducing helpers for xxx_check_funcs(). */
304 static void get_funcs_matrix(int fd, unsigned long *funcs)
306 ioctl_or_perror_and_die(fd, I2C_FUNCS, funcs,
307 "can't get adapter functionality matrix");
310 #if ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP
311 static void check_funcs_test_end(int funcs, int pec, const char *err)
313 if (pec && !(funcs & (I2C_FUNC_SMBUS_PEC | I2C_FUNC_I2C)))
314 bb_error_msg("warning: adapter does not support PEC");
317 bb_error_msg_and_die(
318 "adapter has no %s capability", err);
320 #endif /* ENABLE_I2CGET || ENABLE_I2CSET || ENABLE_I2CDUMP */
323 * The below functions emit an error message and exit if the adapter doesn't
324 * support desired functionalities.
326 #if ENABLE_I2CGET || ENABLE_I2CDUMP
327 static void check_read_funcs(int fd, int mode, int data_addr, int pec)
330 const char *err = NULL;
332 get_funcs_matrix(fd, &funcs);
335 if (!(funcs & I2C_FUNC_SMBUS_READ_BYTE)) {
336 err = "SMBus receive byte";
339 if (data_addr >= 0 && !(funcs & I2C_FUNC_SMBUS_WRITE_BYTE))
340 err = "SMBus send byte";
342 case I2C_SMBUS_BYTE_DATA:
343 if (!(funcs & I2C_FUNC_SMBUS_READ_BYTE_DATA))
344 err = "SMBus read byte";
346 case I2C_SMBUS_WORD_DATA:
347 if (!(funcs & I2C_FUNC_SMBUS_READ_WORD_DATA))
348 err = "SMBus read word";
351 case I2C_SMBUS_BLOCK_DATA:
352 if (!(funcs & I2C_FUNC_SMBUS_READ_BLOCK_DATA))
353 err = "SMBus block read";
356 case I2C_SMBUS_I2C_BLOCK_DATA:
357 if (!(funcs & I2C_FUNC_SMBUS_READ_I2C_BLOCK))
358 err = "I2C block read";
360 #endif /* ENABLE_I2CDUMP */
362 bb_error_msg_and_die("internal error");
364 check_funcs_test_end(funcs, pec, err);
366 #endif /* ENABLE_I2CGET || ENABLE_I2CDUMP */
369 static void check_write_funcs(int fd, int mode, int pec)
372 const char *err = NULL;
374 get_funcs_matrix(fd, &funcs);
377 if (!(funcs & I2C_FUNC_SMBUS_WRITE_BYTE))
378 err = "SMBus send byte";
381 case I2C_SMBUS_BYTE_DATA:
382 if (!(funcs & I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
383 err = "SMBus write byte";
386 case I2C_SMBUS_WORD_DATA:
387 if (!(funcs & I2C_FUNC_SMBUS_WRITE_WORD_DATA))
388 err = "SMBus write word";
391 case I2C_SMBUS_BLOCK_DATA:
392 if (!(funcs & I2C_FUNC_SMBUS_WRITE_BLOCK_DATA))
393 err = "SMBus block write";
395 case I2C_SMBUS_I2C_BLOCK_DATA:
396 if (!(funcs & I2C_FUNC_SMBUS_WRITE_I2C_BLOCK))
397 err = "I2C block write";
400 check_funcs_test_end(funcs, pec, err);
402 #endif /* ENABLE_I2CSET */
404 static void confirm_or_abort(void)
406 fprintf(stderr, "Continue? [y/N] ");
408 if (!bb_ask_confirmation())
409 bb_error_msg_and_die("aborting");
413 * Return only if user confirms the action, abort otherwise.
415 * The messages displayed here are much less elaborate than their i2c-tools
416 * counterparts - this is done for size reduction.
418 static void confirm_action(int bus_addr, int mode, int data_addr, int pec)
420 bb_error_msg("WARNING! This program can confuse your I2C bus");
422 /* Don't let the user break his/her EEPROMs */
423 if (bus_addr >= 0x50 && bus_addr <= 0x57 && pec) {
424 bb_error_msg_and_die("this is I2C not smbus - using PEC on I2C "
425 "devices may result in data loss, aborting");
428 if (mode == I2C_SMBUS_BYTE && data_addr >= 0 && pec)
429 bb_error_msg("WARNING! May interpret a write byte command "
430 "with PEC as a write byte data command");
433 bb_error_msg("PEC checking enabled");
439 //usage:#define i2cget_trivial_usage
440 //usage: "[-f] [-y] BUS CHIP-ADDRESS [DATA-ADDRESS [MODE]]"
441 //usage:#define i2cget_full_usage "\n\n"
442 //usage: "Read from I2C/SMBus chip registers\n"
443 //usage: "\n I2CBUS i2c bus number"
444 //usage: "\n ADDRESS 0x03 - 0x77"
445 //usage: "\nMODE is:"
446 //usage: "\n b read byte data (default)"
447 //usage: "\n w read word data"
448 //usage: "\n c write byte/read byte"
449 //usage: "\n Append p for SMBus PEC"
451 //usage: "\n -f force access"
452 //usage: "\n -y disable interactive mode"
453 int i2cget_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
454 int i2cget_main(int argc UNUSED_PARAM, char **argv)
456 const unsigned opt_f = (1 << 0), opt_y = (1 << 1);
457 const char *const optstr = "fy";
459 int bus_num, bus_addr, data_addr = -1, status;
460 int mode = I2C_SMBUS_BYTE, pec = 0, fd;
463 opt_complementary = "-2:?4"; /* from 2 to 4 args */
464 opts = getopt32(argv, optstr);
467 bus_num = i2c_bus_lookup(argv[0]);
468 bus_addr = i2c_parse_bus_addr(argv[1]);
471 data_addr = i2c_parse_data_addr(argv[2]);
472 mode = I2C_SMBUS_BYTE_DATA;
474 switch (argv[3][0]) {
475 case 'b': /* Already set */ break;
476 case 'w': mode = I2C_SMBUS_WORD_DATA; break;
477 case 'c': mode = I2C_SMBUS_BYTE; break;
479 bb_error_msg("invalid mode");
482 pec = argv[3][1] == 'p';
486 fd = i2c_dev_open(bus_num);
487 check_read_funcs(fd, mode, data_addr, pec);
488 i2c_set_slave_addr(fd, bus_addr, opts & opt_f);
491 confirm_action(bus_addr, mode, data_addr, pec);
498 if (data_addr >= 0) {
499 status = i2c_smbus_write_byte(fd, data_addr);
501 bb_error_msg("warning - write failed");
503 status = i2c_smbus_read_byte(fd);
505 case I2C_SMBUS_WORD_DATA:
506 status = i2c_smbus_read_word_data(fd, data_addr);
508 default: /* I2C_SMBUS_BYTE_DATA */
509 status = i2c_smbus_read_byte_data(fd, data_addr);
514 bb_perror_msg_and_die("read failed");
516 printf("0x%0*x\n", mode == I2C_SMBUS_WORD_DATA ? 4 : 2, status);
520 #endif /* ENABLE_I2CGET */
523 //usage:#define i2cset_trivial_usage
524 //usage: "[-f] [-y] [-m MASK] BUS CHIP-ADDR DATA-ADDR [VALUE] ... [MODE]"
525 //usage:#define i2cset_full_usage "\n\n"
526 //usage: "Set I2C registers\n"
527 //usage: "\n I2CBUS i2c bus number"
528 //usage: "\n ADDRESS 0x03 - 0x77"
529 //usage: "\nMODE is:"
530 //usage: "\n c byte, no value"
531 //usage: "\n b byte data (default)"
532 //usage: "\n w word data"
533 //usage: "\n i I2C block data"
534 //usage: "\n s SMBus block data"
535 //usage: "\n Append p for SMBus PEC"
537 //usage: "\n -f force access"
538 //usage: "\n -y disable interactive mode"
539 //usage: "\n -r read back and compare the result"
540 //usage: "\n -m MASK mask specifying which bits to write"
541 int i2cset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
542 int i2cset_main(int argc, char **argv)
544 const unsigned opt_f = (1 << 0), opt_y = (1 << 1),
545 opt_m = (1 << 2), opt_r = (1 << 3);
546 const char *const optstr = "fym:r";
548 int bus_num, bus_addr, data_addr, mode = I2C_SMBUS_BYTE, pec = 0;
549 int val, blen = 0, mask = 0, fd, status;
550 unsigned char block[I2C_SMBUS_BLOCK_MAX];
551 char *opt_m_arg = NULL;
554 opt_complementary = "-3"; /* from 3 to ? args */
555 opts = getopt32(argv, optstr, &opt_m_arg);
559 bus_num = i2c_bus_lookup(argv[0]);
560 bus_addr = i2c_parse_bus_addr(argv[1]);
561 data_addr = i2c_parse_data_addr(argv[2]);
564 if (!argv[4] && argv[3][0] != 'c') {
565 mode = I2C_SMBUS_BYTE_DATA; /* Implicit b */
567 switch (argv[argc-1][0]) {
568 case 'c': /* Already set */ break;
569 case 'b': mode = I2C_SMBUS_BYTE_DATA; break;
570 case 'w': mode = I2C_SMBUS_WORD_DATA; break;
571 case 's': mode = I2C_SMBUS_BLOCK_DATA; break;
572 case 'i': mode = I2C_SMBUS_I2C_BLOCK_DATA; break;
574 bb_error_msg("invalid mode");
578 pec = argv[argc-1][1] == 'p';
579 if (mode == I2C_SMBUS_BLOCK_DATA ||
580 mode == I2C_SMBUS_I2C_BLOCK_DATA) {
581 if (pec && mode == I2C_SMBUS_I2C_BLOCK_DATA)
582 bb_error_msg_and_die(
583 "PEC not supported for I2C "
586 bb_error_msg_and_die(
587 "mask not supported for block "
593 /* Prepare the value(s) to be written according to current mode. */
595 case I2C_SMBUS_BYTE_DATA:
596 val = xstrtou_range(argv[3], 0, 0, 0xff);
598 case I2C_SMBUS_WORD_DATA:
599 val = xstrtou_range(argv[3], 0, 0, 0xffff);
601 case I2C_SMBUS_BLOCK_DATA:
602 case I2C_SMBUS_I2C_BLOCK_DATA:
603 for (blen = 3; blen < (argc - 1); blen++)
604 block[blen] = xstrtou_range(argv[blen], 0, 0, 0xff);
613 mask = xstrtou_range(opt_m_arg, 0, 0,
614 (mode == I2C_SMBUS_BYTE ||
615 mode == I2C_SMBUS_BYTE_DATA) ? 0xff : 0xffff);
618 fd = i2c_dev_open(bus_num);
619 check_write_funcs(fd, mode, pec);
620 i2c_set_slave_addr(fd, bus_addr, opts & opt_f);
623 confirm_action(bus_addr, mode, data_addr, pec);
626 * If we're using mask - read the current value here and adjust the
627 * value to be written.
634 tmpval = i2c_smbus_read_byte(fd);
636 case I2C_SMBUS_WORD_DATA:
637 tmpval = i2c_smbus_read_word_data(fd, data_addr);
640 tmpval = i2c_smbus_read_byte_data(fd, data_addr);
644 bb_perror_msg_and_die("can't read old value");
646 val = (val & mask) | (tmpval & ~mask);
648 if (!(opts & opt_y)) {
649 bb_error_msg("old value 0x%0*x, write mask "
650 "0x%0*x, will write 0x%0*x to register "
652 mode == I2C_SMBUS_WORD_DATA ? 4 : 2, tmpval,
653 mode == I2C_SMBUS_WORD_DATA ? 4 : 2, mask,
654 mode == I2C_SMBUS_WORD_DATA ? 4 : 2, val,
665 status = i2c_smbus_write_byte(fd, data_addr);
667 case I2C_SMBUS_WORD_DATA:
668 status = i2c_smbus_write_word_data(fd, data_addr, val);
670 case I2C_SMBUS_BLOCK_DATA:
671 status = i2c_smbus_write_block_data(fd, data_addr,
674 case I2C_SMBUS_I2C_BLOCK_DATA:
675 status = i2c_smbus_write_i2c_block_data(fd, data_addr,
678 default: /* I2C_SMBUS_BYTE_DATA */
679 status = i2c_smbus_write_byte_data(fd, data_addr, val);
683 bb_perror_msg_and_die("write failed");
686 i2c_set_pec(fd, 0); /* Clear PEC. */
688 /* No readback required - we're done. */
694 status = i2c_smbus_read_byte(fd);
697 case I2C_SMBUS_WORD_DATA:
698 status = i2c_smbus_read_word_data(fd, data_addr);
700 default: /* I2C_SMBUS_BYTE_DATA */
701 status = i2c_smbus_read_byte_data(fd, data_addr);
705 puts("Warning - readback failed");
708 printf("Warning - data mismatch - wrote "
709 "0x%0*x, read back 0x%0*x\n",
710 mode == I2C_SMBUS_WORD_DATA ? 4 : 2, val,
711 mode == I2C_SMBUS_WORD_DATA ? 4 : 2, status);
713 printf("Value 0x%0*x written, readback matched\n",
714 mode == I2C_SMBUS_WORD_DATA ? 4 : 2, val);
719 #endif /* ENABLE_I2CSET */
722 static int read_block_data(int buf_fd, int mode, int *block)
724 uint8_t cblock[I2C_SMBUS_BLOCK_MAX + I2CDUMP_NUM_REGS];
725 int res, blen = 0, tmp, i;
727 if (mode == I2C_SMBUS_BLOCK_DATA) {
728 blen = i2c_smbus_read_block_data(buf_fd, 0, cblock);
732 for (res = 0; res < I2CDUMP_NUM_REGS; res += tmp) {
733 tmp = i2c_smbus_read_i2c_block_data(
734 buf_fd, res, I2C_SMBUS_BLOCK_MAX,
742 if (res >= I2CDUMP_NUM_REGS)
743 res = I2CDUMP_NUM_REGS;
745 for (i = 0; i < res; i++)
746 block[i] = cblock[i];
748 if (mode != I2C_SMBUS_BLOCK_DATA)
749 for (i = res; i < I2CDUMP_NUM_REGS; i++)
756 bb_error_msg_and_die("block read failed: %d", blen);
759 /* Dump all but word data. */
760 static void dump_data(int bus_fd, int mode, unsigned first,
761 unsigned last, int *block, int blen)
765 puts(" 0 1 2 3 4 5 6 7 8 9 a b c d e f"
766 " 0123456789abcdef");
768 for (i = 0; i < I2CDUMP_NUM_REGS; i += 0x10) {
769 if (mode == I2C_SMBUS_BLOCK_DATA && i >= blen)
777 for (j = 0; j < 16; j++) {
779 /* Skip unwanted registers */
780 if (i+j < first || i+j > last) {
782 if (mode == I2C_SMBUS_WORD_DATA) {
790 case I2C_SMBUS_BYTE_DATA:
791 res = i2c_smbus_read_byte_data(bus_fd, i+j);
794 case I2C_SMBUS_WORD_DATA:
795 res = i2c_smbus_read_word_data(bus_fd, i+j);
800 block[i+j] = res & 0xff;
801 block[i+j+1] = res >> 8;
805 res = i2c_smbus_read_byte(bus_fd);
812 if (mode == I2C_SMBUS_BLOCK_DATA &&
815 } else if (res < 0) {
817 if (mode == I2C_SMBUS_WORD_DATA)
820 printf("%02x ", block[i+j]);
821 if (mode == I2C_SMBUS_WORD_DATA)
822 printf("%02x ", block[i+j+1]);
825 if (mode == I2C_SMBUS_WORD_DATA)
830 for (j = 0; j < 16; j++) {
831 if (mode == I2C_SMBUS_BLOCK_DATA && i+j >= blen)
833 /* Skip unwanted registers */
834 if (i+j < first || i+j > last) {
842 } else if (res == 0x00 || res == 0xff) {
844 } else if (res < 32 || res >= 127) {
854 static void dump_word_data(int bus_fd, unsigned first, unsigned last)
859 puts(" 0,8 1,9 2,a 3,b 4,c 5,d 6,e 7,f");
860 for (i = 0; i < 256; i += 8) {
867 for (j = 0; j < 8; j++) {
868 /* Skip unwanted registers. */
869 if (i+j < first || i+j > last) {
874 rv = i2c_smbus_read_word_data(bus_fd, i+j);
878 printf("%04x ", rv & 0xffff);
884 //usage:#define i2cdump_trivial_usage
885 //usage: "[-f] [-r FIRST-LAST] [-y] BUS ADDR [MODE]"
886 //usage:#define i2cdump_full_usage "\n\n"
887 //usage: "Examine I2C registers\n"
888 //usage: "\n I2CBUS i2c bus number"
889 //usage: "\n ADDRESS 0x03 - 0x77"
890 //usage: "\nMODE is:"
891 //usage: "\n b byte (default)"
893 //usage: "\n W word on even register addresses"
894 //usage: "\n i I2C block"
895 //usage: "\n s SMBus block"
896 //usage: "\n c consecutive byte"
897 //usage: "\n Append p for SMBus PEC"
899 //usage: "\n -f force access"
900 //usage: "\n -y disable interactive mode"
901 //usage: "\n -r limit the number of registers being accessed"
902 int i2cdump_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
903 int i2cdump_main(int argc UNUSED_PARAM, char **argv)
905 const unsigned opt_f = (1 << 0), opt_y = (1 << 1),
907 const char *const optstr = "fyr:";
909 int bus_num, bus_addr, mode = I2C_SMBUS_BYTE_DATA, even = 0, pec = 0;
910 unsigned first = 0x00, last = 0xff, opts;
911 int block[I2CDUMP_NUM_REGS];
912 char *opt_r_str, *dash;
915 opt_complementary = "-2:?3"; /* from 2 to 3 args */
916 opts = getopt32(argv, optstr, &opt_r_str);
919 bus_num = i2c_bus_lookup(argv[0]);
920 bus_addr = i2c_parse_bus_addr(argv[1]);
923 switch (argv[2][0]) {
924 case 'b': /* Already set. */ break;
925 case 'c': mode = I2C_SMBUS_BYTE; break;
926 case 'w': mode = I2C_SMBUS_WORD_DATA; break;
928 mode = I2C_SMBUS_WORD_DATA;
931 case 's': mode = I2C_SMBUS_BLOCK_DATA; break;
932 case 'i': mode = I2C_SMBUS_I2C_BLOCK_DATA; break;
934 bb_error_msg_and_die("invalid mode");
937 if (argv[2][1] == 'p') {
938 if (argv[2][0] == 'W' || argv[2][0] == 'i') {
939 bb_error_msg_and_die(
940 "pec not supported for -W and -i");
948 first = strtol(opt_r_str, &dash, 0);
949 if (dash == opt_r_str || *dash != '-' || first > 0xff)
950 bb_error_msg_and_die("invalid range");
951 last = xstrtou_range(++dash, 0, first, 0xff);
953 /* Range is not available for every mode. */
956 case I2C_SMBUS_BYTE_DATA:
958 case I2C_SMBUS_WORD_DATA:
959 if (!even || (!(first % 2) && last % 2))
963 bb_error_msg_and_die(
964 "range not compatible with selected mode");
968 fd = i2c_dev_open(bus_num);
969 check_read_funcs(fd, mode, -1 /* data_addr */, pec);
970 i2c_set_slave_addr(fd, bus_addr, opts & opt_f);
976 confirm_action(bus_addr, mode, -1 /* data_addr */, pec);
978 /* All but word data. */
979 if (mode != I2C_SMBUS_WORD_DATA || even) {
982 if (mode == I2C_SMBUS_BLOCK_DATA || mode == I2C_SMBUS_I2C_BLOCK_DATA)
983 blen = read_block_data(fd, mode, block);
985 if (mode == I2C_SMBUS_BYTE) {
986 res = i2c_smbus_write_byte(fd, first);
988 bb_perror_msg_and_die("write start address");
991 dump_data(fd, mode, first, last, block, blen);
993 dump_word_data(fd, first, last);
998 #endif /* ENABLE_I2CDUMP */
1000 #if ENABLE_I2CDETECT
1013 static const struct adap_desc adap_descs[] = {
1015 .algo = "Dummy bus", },
1017 .algo = "ISA bus", },
1019 .algo = "I2C adapter", },
1021 .algo = "SMBus adapter", },
1030 static const struct i2c_func i2c_funcs_tab[] = {
1031 { .value = I2C_FUNC_I2C,
1033 { .value = I2C_FUNC_SMBUS_QUICK,
1034 .name = "SMBus quick command" },
1035 { .value = I2C_FUNC_SMBUS_WRITE_BYTE,
1036 .name = "SMBus send byte" },
1037 { .value = I2C_FUNC_SMBUS_READ_BYTE,
1038 .name = "SMBus receive byte" },
1039 { .value = I2C_FUNC_SMBUS_WRITE_BYTE_DATA,
1040 .name = "SMBus write byte" },
1041 { .value = I2C_FUNC_SMBUS_READ_BYTE_DATA,
1042 .name = "SMBus read byte" },
1043 { .value = I2C_FUNC_SMBUS_WRITE_WORD_DATA,
1044 .name = "SMBus write word" },
1045 { .value = I2C_FUNC_SMBUS_READ_WORD_DATA,
1046 .name = "SMBus read word" },
1047 { .value = I2C_FUNC_SMBUS_PROC_CALL,
1048 .name = "SMBus process call" },
1049 { .value = I2C_FUNC_SMBUS_WRITE_BLOCK_DATA,
1050 .name = "SMBus block write" },
1051 { .value = I2C_FUNC_SMBUS_READ_BLOCK_DATA,
1052 .name = "SMBus block read" },
1053 { .value = I2C_FUNC_SMBUS_BLOCK_PROC_CALL,
1054 .name = "SMBus block process call" },
1055 { .value = I2C_FUNC_SMBUS_PEC,
1056 .name = "SMBus PEC" },
1057 { .value = I2C_FUNC_SMBUS_WRITE_I2C_BLOCK,
1058 .name = "I2C block write" },
1059 { .value = I2C_FUNC_SMBUS_READ_I2C_BLOCK,
1060 .name = "I2C block read" },
1061 { .value = 0, .name = NULL }
1064 static enum adapter_type i2cdetect_get_funcs(int bus)
1066 enum adapter_type ret;
1067 unsigned long funcs;
1070 fd = i2c_dev_open(bus);
1072 get_funcs_matrix(fd, &funcs);
1073 if (funcs & I2C_FUNC_I2C)
1075 else if (funcs & (I2C_FUNC_SMBUS_BYTE |
1076 I2C_FUNC_SMBUS_BYTE_DATA |
1077 I2C_FUNC_SMBUS_WORD_DATA))
1087 static void NORETURN list_i2c_busses_and_exit(void)
1089 const char *const i2cdev_path = "/sys/class/i2c-dev";
1091 char path[NAME_MAX], name[128];
1092 struct dirent *de, *subde;
1093 enum adapter_type adt;
1100 * XXX Upstream i2cdetect also looks for i2c bus info in /proc/bus/i2c,
1101 * but we won't bother since it's only useful on older kernels (before
1102 * 2.6.5). We expect sysfs to be present and mounted at /sys/.
1105 dir = xopendir(i2cdev_path);
1106 while ((de = readdir(dir))) {
1107 if (de->d_name[0] == '.')
1110 /* Simple version for ISA chips. */
1111 snprintf(path, NAME_MAX, "%s/%s/name",
1112 i2cdev_path, de->d_name);
1113 fp = fopen(path, "r");
1115 snprintf(path, NAME_MAX,
1116 "%s/%s/device/name",
1117 i2cdev_path, de->d_name);
1118 fp = fopen(path, "r");
1121 /* Non-ISA chips require the hard-way. */
1123 snprintf(path, NAME_MAX,
1124 "%s/%s/device/name",
1125 i2cdev_path, de->d_name);
1126 subdir = opendir(path);
1130 while ((subde = readdir(subdir))) {
1131 if (subde->d_name[0] == '.')
1134 if (is_prefixed_with(subde->d_name, "i2c-")) {
1135 snprintf(path, NAME_MAX,
1136 "%s/%s/device/%s/name",
1137 i2cdev_path, de->d_name,
1139 fp = fopen(path, "r");
1147 * Get the rest of the info and display a line
1150 memset(name, 0, sizeof(name));
1151 pos = fgets(name, sizeof(name), fp);
1156 pos = strchr(name, '\n');
1160 rv = sscanf(de->d_name, "i2c-%d", &bus);
1164 if (is_prefixed_with(name, "ISA"))
1167 adt = i2cdetect_get_funcs(bus);
1170 "i2c-%d\t%-10s\t%-32s\t%s\n",
1171 bus, adap_descs[adt].funcs,
1172 name, adap_descs[adt].algo);
1179 static void NORETURN no_support(const char *cmd)
1181 bb_error_msg_and_die("bus doesn't support %s", cmd);
1184 static void will_skip(const char *cmd)
1187 "warning: can't use %s command, "
1188 "will skip some addresses", cmd);
1191 //usage:#define i2cdetect_trivial_usage
1192 //usage: "[-F I2CBUS] [-l] [-y] [-a] [-q|-r] I2CBUS [FIRST LAST]"
1193 //usage:#define i2cdetect_full_usage "\n\n"
1194 //usage: "Detect I2C chips.\n"
1195 //usage: "\n I2CBUS i2c bus number"
1196 //usage: "\n FIRST and LAST limit the probing range"
1198 //usage: "\n -l output list of installed busses"
1199 //usage: "\n -y disable interactive mode"
1200 //usage: "\n -a force scanning of non-regular addresses"
1201 //usage: "\n -q use smbus quick write commands for probing (default)"
1202 //usage: "\n -r use smbus read byte commands for probing"
1203 //usage: "\n -F display list of functionalities"
1204 int i2cdetect_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
1205 int i2cdetect_main(int argc UNUSED_PARAM, char **argv)
1207 const unsigned opt_y = (1 << 0), opt_a = (1 << 1),
1208 opt_q = (1 << 2), opt_r = (1 << 3),
1209 opt_F = (1 << 4), opt_l = (1 << 5);
1210 const char *const optstr = "yaqrFl";
1212 int fd, bus_num, i, j, mode = I2CDETECT_MODE_AUTO, status, cmd;
1213 unsigned first = 0x03, last = 0x77, opts;
1214 unsigned long funcs;
1216 opt_complementary = "q--r:r--q:" /* mutually exclusive */
1217 "?3"; /* up to 3 args */
1218 opts = getopt32(argv, optstr);
1222 list_i2c_busses_and_exit();
1227 bus_num = i2c_bus_lookup(argv[0]);
1228 fd = i2c_dev_open(bus_num);
1229 get_funcs_matrix(fd, &funcs);
1232 /* Only list the functionalities. */
1233 printf("Functionalities implemented by bus #%d\n", bus_num);
1234 for (i = 0; i2c_funcs_tab[i].value; i++) {
1235 printf("%-32s %s\n", i2c_funcs_tab[i].name,
1236 funcs & i2c_funcs_tab[i].value ? "yes" : "no");
1239 return EXIT_SUCCESS;
1243 mode = I2CDETECT_MODE_READ;
1244 else if (opts & opt_q)
1245 mode = I2CDETECT_MODE_QUICK;
1252 /* Read address range. */
1254 first = xstrtou_range(argv[1], 16, first, last);
1256 last = xstrtou_range(argv[2], 16, first, last);
1259 if (!(funcs & (I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_READ_BYTE))) {
1260 no_support("detection commands");
1262 if (mode == I2CDETECT_MODE_QUICK && !(funcs & I2C_FUNC_SMBUS_QUICK)) {
1263 no_support("SMBus quick write");
1265 if (mode == I2CDETECT_MODE_READ && !(funcs & I2C_FUNC_SMBUS_READ_BYTE)) {
1266 no_support("SMBus receive byte");
1269 if (mode == I2CDETECT_MODE_AUTO) {
1270 if (!(funcs & I2C_FUNC_SMBUS_QUICK))
1271 will_skip("SMBus quick write");
1272 if (!(funcs & I2C_FUNC_SMBUS_READ_BYTE))
1273 will_skip("SMBus receive byte");
1276 if (!(opts & opt_y))
1277 confirm_action(-1, -1, -1, 0);
1279 puts(" 0 1 2 3 4 5 6 7 8 9 a b c d e f");
1280 for (i = 0; i < 128; i += 16) {
1281 printf("%02x: ", i);
1282 for (j = 0; j < 16; j++) {
1286 if (mode == I2CDETECT_MODE_AUTO) {
1287 if ((i+j >= 0x30 && i+j <= 0x37) ||
1288 (i+j >= 0x50 && i+j <= 0x5F))
1289 cmd = I2CDETECT_MODE_READ;
1291 cmd = I2CDETECT_MODE_QUICK;
1294 /* Skip unwanted addresses. */
1297 || (cmd == I2CDETECT_MODE_READ && !(funcs & I2C_FUNC_SMBUS_READ_BYTE))
1298 || (cmd == I2CDETECT_MODE_QUICK && !(funcs & I2C_FUNC_SMBUS_QUICK)))
1304 status = ioctl(fd, I2C_SLAVE, itoptr(i + j));
1306 if (errno == EBUSY) {
1311 bb_perror_msg_and_die(
1312 "can't set address to 0x%02x", i + j);
1316 case I2CDETECT_MODE_READ:
1318 * This is known to lock SMBus on various
1319 * write-only chips (mainly clock chips).
1321 status = i2c_smbus_read_byte(fd);
1323 default: /* I2CDETECT_MODE_QUICK: */
1325 * This is known to corrupt the Atmel
1328 status = i2c_smbus_write_quick(fd,
1336 printf("%02x ", i+j);
1343 #endif /* ENABLE_I2CDETECT */