root/lm-sensors/trunk/prog/detect/i2cdetect.c @ 2695

/*
    i2cdetect.c - a user-space program to scan for I2C devices
    Copyright (C) 1999-2004  Frodo Looijaard <frodol@dds.nl>,
                             Mark D. Studebaker <mdsxyz123@yahoo.com> and
                             Jean Delvare <khali@linux-fr.org>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <errno.h>
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "../dump/i2cbusses.h"
#include "i2c-dev.h"
#include "version.h"

#define MODE_AUTO       0
#define MODE_QUICK      1
#define MODE_READ       2

void help(void)
{
        fprintf(stderr,
                "Syntax: i2cdetect [-f] [-q|-r] I2CBUS [FIRST LAST]\n"
                "  I2CBUS is an integer\n"
                "  With -f, scans all addresses (NOT RECOMMENDED)\n"
                "  With -q, uses only quick write commands for probing (NOT "
                "RECOMMENDED)\n"
                "  With -r, uses only read byte commands for probing (NOT "
                "RECOMMENDED)\n"
                "  If provided, FIRST and LAST limit the probing range.\n"
                "  i2cdetect -l lists installed busses only\n");
}

int scan_i2c_bus(int file, const int mode, const int first, const int last)
{
        int i, j;
        int res;

        printf("     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f\n");

        for (i = 0; i < 128; i += 16) {
                printf("%02x: ", i);
                for(j = 0; j < 16; j++) {
                        /* Skip unwanted addresses */
                        if (i+j < first || i+j > last) {
                                printf("   ");
                                continue;
                        }

                        /* Set slave address */
                        if (ioctl(file, I2C_SLAVE, i+j) < 0) {
                                if (errno == EBUSY) {
                                        printf("UU ");
                                        continue;
                                } else {
                                        fprintf(stderr, "Error: Could not set "
                                                "address to 0x%02x: %s\n", i+j,
                                                strerror(errno));
                                        return -1;
                                }
                        }

                        /* Probe this address */
                        switch (mode) {
                        case MODE_QUICK:
                                /* This is known to corrupt the Atmel AT24RF08
                                   EEPROM */
                                res = i2c_smbus_write_quick(file,
                                      I2C_SMBUS_WRITE);
                                break;
                        case MODE_READ:
                                /* This is known to lock SMBus on various
                                   write-only chips (mainly clock chips) */
                                res = i2c_smbus_read_byte(file);
                                break;
                        default:
                                if ((i+j >= 0x30 && i+j <= 0x37)
                                 || (i+j >= 0x50 && i+j <= 0x5F))
                                        res = i2c_smbus_read_byte(file);
                                else
                                        res = i2c_smbus_write_quick(file,
                                              I2C_SMBUS_WRITE);
                        }

                        if (res < 0)
                                printf("XX ");
                        else
                                printf("%02x ", i+j);
                }
                printf("\n");
        }

        return 0;
}

int main(int argc, char *argv[])
{
        char *end;
        int i = 1, i2cbus = -1, file, res;
        char filename[20];
        long funcs;
        int mode = MODE_AUTO;
        int first = 0x03, last = 0x77;

        while(i2cbus == -1) {
                if (i >= argc) {
                        fprintf(stderr, "Error: No i2c-bus specified!\n");
                        help();
                        exit(1);
                }

                if(!strcasecmp(argv[i], "-v")) {
                        fprintf(stderr, "i2cdetect version %s\n", LM_VERSION);
                        exit(0);
                }

                if(!strcmp(argv[i], "-l")) {
                        print_i2c_busses(1);
                        exit(0);
                }

                if(!strcmp(argv[i], "-f")) {
                        first = 0x00;
                        last = 0x7F;
                        i++;
                } else
                if(!strcmp(argv[i], "-q")) {
                        if (mode != MODE_AUTO) {
                                fprintf(stderr, "Error: Different modes "
                                        "specified!\n");
                                exit(1);
                        }
                        mode = MODE_QUICK;
                        i++;
                } else
                if(!strcmp(argv[i], "-r")) {
                        if (mode != MODE_AUTO) {
                                fprintf(stderr, "Error: Different modes "
                                        "specified!\n");
                                exit(1);
                        }
                        mode = MODE_READ;
                        i++;
                } else {
                        i2cbus = strtol(argv[i],&end,0);
                        if (*end) {
                                fprintf(stderr, "Error: I2CBUS argument not a "
                                        "number!\n");
                                help();
                                exit(1);
                        }
                        if ((i2cbus < 0) || (i2cbus > 0xff)) {
                                fprintf(stderr, "Error: I2CBUS argument out "
                                        "of range (0-255)!\n");
                                help();
                                exit(1);
                        }
                        i++;
                }
        }

        /* read address range if present */
        if (i+2 == argc) {
                int tmp;

                tmp = strtol(argv[i], &end, 0);
                if (*end) {
                        fprintf(stderr, "Error: FIRST argment not a "
                                "number!\n");
                        help();
                        exit(1);
                }
                if (tmp < first || tmp > last) {
                        fprintf(stderr, "Error: FIRST argument out of range "
                                "(0x%02x-0x%02x)!\n", first, last);
                        help();
                        exit(1);
                }
                first = tmp;

                tmp = strtol(argv[i+1], &end, 0);
                if (*end) {
                        fprintf(stderr, "Error: LAST argment not a "
                                "number!\n");
                        help();
                        exit(1);
                }
                if (tmp < first || tmp > last) {
                        fprintf(stderr, "Error: LAST argument out of range "
                                "(0x%02x-0x%02x)!\n", first, last);
                        help();
                        exit(1);
                }
                last = tmp;
        } else if (i != argc) {
                help();
                exit(1);
        }

        file = open_i2c_dev(i2cbus, filename);
        if (file < 0) {
                exit(1);
        }

        if (ioctl(file,I2C_FUNCS,&funcs) < 0) {
                fprintf(stderr, "Error: Could not get the adapter "
                        "functionality matrix: %s\n", strerror(errno));
                close(file);
                exit(1);
        }
        if (mode != MODE_READ && !(funcs & I2C_FUNC_SMBUS_QUICK)) {
                fprintf(stderr, "Error: Can't use SMBus Quick Write command "
                        "on this bus (ISA bus?)\n");
                close(file);
                exit(1);
        }
        if (mode != MODE_QUICK && !(funcs & I2C_FUNC_SMBUS_READ_BYTE)) {
                fprintf(stderr, "Error: Can't use SMBus Read Byte command "
                        "on this bus (ISA bus?)\n");
                close(file);
                exit(1);
        }

        fprintf(stderr, "  WARNING! This program can confuse your I2C bus, "
                "cause data loss and worse!\n");
        fprintf(stderr, "  I will probe file %s%s.\n", filename,
                mode==MODE_QUICK?" using quick write commands":
                mode==MODE_READ?" using read byte commands":"");
        fprintf(stderr, "  I will probe address range 0x%02x-0x%02x.\n",
                first, last);
        fprintf(stderr, "  You have five seconds to reconsider and press "
                "CTRL-C!\n\n");
        sleep(5);

        res = scan_i2c_bus(file, mode, first, last);

        close(file);

        exit(res?1:0);
}