commandline/i2cget.c


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#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "i2c-util.h"

int main(int argc, char **argv)
{
	int address, command, got_ack;
	unsigned int ret;
	char mode = 'c';
	char *conv_err;

	i2c_init();
	i2c_start();

	if (argc < 3) {
		fputs("Usage: vusb-i2cget <address> <register> [mode]", stderr);
		return 1;
	}

	address = strtol(argv[1], &conv_err, 0);

	if (conv_err && *conv_err) {
		fprintf(stderr, "address: Conversion error at '%s'", conv_err);
		return 2;
	}

	command = strtol(argv[2], &conv_err, 0);

	if (conv_err && *conv_err) {
		fprintf(stderr, "command: conversion error at '%s'", conv_err);
		return 2;
	}

	if (argc == 4)
		mode = argv[3][0];

	i2c_tx_byte((address << 1) | 0);
	i2c_tx_byte(command);
	i2c_start();
	got_ack = i2c_tx_byte((address << 1) | 1);

	if (mode == 'i') {
		ret = i2c_rx_byte(1);
		ret |= (i2c_rx_byte(0) << 8);
	}
	else
		ret = i2c_rx_byte(0);

	i2c_stop();
	i2c_deinit();

	printf("%i\n", ret);

	return got_ack ? 0 : 1;
}