How to interfcae i2c bus of a chip on my hardware to qt application

[ananthavidhya]

Hello Everyone,
I recently working on developing qt application for accessing a rtc chip whose i2c address is 0x24. For this chip we need to fuse a register to set date and time through command line. that what i am trying to replace with gui in which if i press a button i2c registers have to write data like as below which i am doing in command line
i2cset -f -y 0 0x24 0x10 0xb1 && i2cset -f -y 0 0x24 0x10 0xfe && i2cset -f -y 0 0x24 0x10 0xa3
at the same time if i press status button it should read the i2c register equivalent to below command
i2cget -f -y 0 0x24 0x05
To am trying out to achive this in better way ..but i am strucked in middle can some one help me with good reference of how to achive this ?
or basic way to control read and write using qt gui methods.
Thanks in advance
A..N.V.Lavanya

[jsulm]

@ananthavidhya There is nothing in Qt to access i2c, but you can use libraries see https://forum.qt.io/topic/114267/qt-functions-for-i2c

[ananthavidhya]

i used direct kernel drivers related i2c application. But unfortunately my code is not working as i expected instead it disturbed some other i2c bus address of emmc chip . I am really have no idea about how that happened.
sincerely seeking for help in proceeding further.
Prior Thanks
A.N.V.Lavanya

here i am attaching my mainwindow.cpp file. any sort of help is needy

#include "mainwindow.h"
#include "ui_mainwindow.h"
//*****************
#include <QTimer>
#include <QDateTime>
#include <QDate>
//*****************

//******i2c handling c++ code*******
#include <linux/i2c-dev.h>

#include <sys/stat.h>
#include <linux/i2c.h>

//#include <i2c/smbus.h>
#include <fcntl.h>// for opening file
#include <sys/ioctl.h> //IOCTL FUNCTION
#include <unistd.h>//READ AND WRITE FUNCTIONS
int file;
#include <QDebug>

int i2c_fd = -1;
typedef unsigned char   u8;

//***********************************
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
     ui->setupUi(this);
//   showTime();
     QTimer *timer=new QTimer(this);
     connect(timer ,SIGNAL(timeout()),this,SLOT(showTime()));
     timer->start();
     showDate();
     int nI2COpenResault = i2c_init(0x24);
 ui->textEdit->append(QString("I2C Open result:%1").arg(nI2COpenResault));
}
int MainWindow::i2c_init(int addr)
{
      QString sFilename = "/dev/i2c-0";
      QByteArray ba = sFilename.toLocal8Bit();
      const char *filename = ba.data();
//        int adapter_nr = 0;
//        char filename[20];
//        snprintf(filename, 19, "/dev/i2c-%d", adapter_nr);
//        file = open(filename, O_RDWR);
//        if(file < 0)
//        {
//            qDebug() << "Open i2c-0 file failed.";
//            return file;
//        }
//        int ret = ioctl(file, I2C_SLAVE, addr);
//        if(ret < 0)
//        {
//            qDebug() << "Open Buss failed.";
//            return ret;
//        }
//        return ret;

    if ((i2c_fd = open(filename, O_RDWR)) < 0) {
            char err[200];
            sprintf(err, "open('%s') in i2c_init", filename);
            perror(err);
            return -1;
        }
        return i2c_fd;
}
int MainWindow::I2C_Close()
{
    if(file == -1)
        return -1;
    ::close(file);
    return 0;
}

MainWindow::~MainWindow()
{
    delete ui;
    I2C_Close();
}



void MainWindow::showTime()
{
    QTime time=QTime::currentTime();
      QString timetext=time.toString("hh : mm : ss");
    //blink the  colon at every sec
    if((time.second() % 2) == 0)
//    {
//        timetext[3] = ' ';
//        timetext[8] = ' ';
//    }
    ui->label->setText(timetext);
}
void MainWindow::showDate()
{
    QDate date = QDate::currentDate();

    /////////////////////////////////////////
    //       Format        Result          //
    //    dd.MM.yyyy      21.05.2001       //
    //    ddd MMMM d yy   Tue May 21 01    //
    //    hh:mm:ss.zzz	  14:13:09.120     //
    //    hh:mm:ss.z	  14:13:09.12      //
    //    h:m:s ap	      2:13:9 pm        //
    //    H:m:s a         14:16:0 pm       //
    /////////////////////////////////////////


    QString datetext=date.toString("dd : MM : yyyy");
    ui->label_2->setText(datetext);

}

void MainWindow::on_Status_Read_clicked()
{
        //i2cget -f -y 0 0x24 0x05  == 0x28 before fuse burn; 0xa8 after fuse burn;

//        char *rbuf = new char;

//        char cWriteData[2] = {ui->addr1->text().toInt(), ui->addr2->text().toInt()};
//        int nWriteResult = I2C_Write(cWriteData, 2); // 需先寫入2byte欲讀出資料之位址
//        usleep(1000);
//        int nReadResult = I2C_Read(rbuf, ui->read_length->text().toInt());
//        ui->textEdit->append(QString("ReadWrite Result:%1").arg(nWriteResult));
//        ui->textEdit->append(QString("Read Result:%1").arg(nReadResult));
//        ui->textEdit->append(QString("Read Data:%1").arg((int)*rbuf));
//        delete rbuf;
       int  Result;
      Result = I2C_Read(0x24,0x05, unsigned char *result);
       ui->data->setText(QString(Result));
}
void MainWindow::on_i2creg_write_clicked()
{

         char cWriteData[2];
        cWriteData[0] = 0x05;
        cWriteData[1] = ui->data->text().toInt();
        int nResult = I2C_Write(cWriteData, 2);
        ui->textEdit->append(QString("write Result:%1").arg(nResult));
}

int MainWindow::I2C_Write(u8 slave_addr, u8 reg, u8 data);
{


    int retval;
        u8 outbuf[2];

        struct i2c_msg msgs[1];
        struct i2c_rdwr_ioctl_data msgset[1];

        outbuf[0] = reg;
        outbuf[1] = data;

        msgs[0].addr = slave_addr;
        msgs[0].flags = 0;
        msgs[0].len = 2;
        msgs[0].buf = outbuf;

        msgset[0].msgs = msgs;
        msgset[0].nmsgs = 1;

        if (ioctl(i2c_fd, I2C_RDWR, &msgset) < 0) {
            perror("ioctl(I2C_RDWR) in i2c_write");
            return -1;
        }

        return 0;
    }

}

int MainWindow::I2C_Read(unsigned char slave_addr, unsigned char reg, unsigned char *result)
{


    //*************************************//
    int retval;
        unsigned char outbuf[1], inbuf[1];
        struct i2c_msg msgs[2];
        struct i2c_rdwr_ioctl_data msgset[1];

        msgs[0].addr = slave_addr;
        msgs[0].flags = 0;
        msgs[0].len = 1;
        msgs[0].buf = outbuf;

        msgs[1].addr = slave_addr;
        msgs[1].flags = I2C_M_RD | I2C_M_NOSTART;
        msgs[1].len = 1;
        msgs[1].buf = inbuf;

        msgset[0].msgs = msgs;
        msgset[0].nmsgs = 2;

        outbuf[0] = reg;

        inbuf[0] = 0;

        *result = 0;
        if (ioctl(i2c_fd, I2C_RDWR, &msgset) < 0) {
            perror("ioctl(I2C_RDWR) in i2c_read");
            return -1;
        }

        *result = inbuf[0];
        return 0;
}
void MainWindow::update_date_time()
{
//        QDateEdit *dateEdit = new QDateEdit(this);
//        QTimeEdit *timeEdit = new QTimeEdit(this);
//    ui->daeTimeEdit->setDateTime(QDateTime::currentDateTime());
//        ui->dateEdit->displayFormat(hh );
        ui->label->setText(ui->timeEdit->text());
        ui->label->update();
        ui->label_2->setText(ui->dateEdit->text());
        ui->label_2->update();


}


void MainWindow::on_set_date_clicked()
{

//    QDateTime dateTimeEdit=new QDateTimeEdit(QDateTime::currentDateTime(),this);
//    dateTimeEdit->setDisplayFormat("yyyy.MMM.dd hh:mm");
//    exec=new QProcess(this)
//    exec->start("touch", QStringList() << "-t" <<dateTimeEdit->dateTime().toString("yyyyMMddhhmm")<<file_path);
//    exec->waitForFinished();
          QTime newModifiedTime = ui->timeEdit->time();
            QDate newModifiedDate=ui->dateEdit->date();
//        QDateTime newCreationDate=TimeEdit_Creation->dateTime();


//        system("date -s \"date");
//           system("date -s \"newModifiedTime newModifiedDate");
//        system("hwclock -w");
//        system("reboot");
        update_date_time();
}