UART Initialization Failed

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Based on the provided context, it seems like you are encountering an issue with opening the UART device on your Verdin iMX8MP module. Here are a few steps to troubleshoot and potentially resolve the issue:

  1. Check Device Path: Ensure that the device path you are using is correct. For Verdin family, the UART device names are typically /dev/verdin-uart1, /dev/verdin-uart2, etc. Verify that the device path you are passing to the initUART function matches one of these.

  2. Permissions: Ensure that your application has the necessary permissions to access the UART device. You might need to run your application with elevated privileges or adjust the permissions of the device file.

  3. Device Availability: Verify that the UART device is available and not being used by another process. You can list the available UART devices using the command:

    ls /dev/verdin-uart*

  4. Error Handling: Enhance your error handling to get more information about why the open call is failing. You can use perror to print the error message:

    if (uartFd == -1) {
    perror("Error opening UART device");
    return -1;
}

  5. Baud Rate: Ensure that the baud rate you are setting is supported. The standard baud rates are predefined, and you should use one of those.

Here is an updated version of your code with enhanced error handling:

#include <fcntl.h>
#include <termios.h>
#include <unistd.h>
#include <stdio.h>
#include <QDebug>

int UARTModule::initUART(const char *device, int baudRate) {
    uartFd = open(device, O_RDWR | O_NOCTTY | O_NDELAY);
    if (uartFd == -1) {
        perror("Error opening UART device");
        return -1;
    }

    struct termios options;
    if (tcgetattr(uartFd, &options) != 0) {
        perror("Error getting UART attributes");
        close(uartFd);
        return -1;
    }

    cfsetispeed(&options, baudRate);
    cfsetospeed(&options, baudRate);

    options.c_cflag |= (CLOCAL | CREAD); // Enable the receiver and set local mode
    options.c_cflag &= ~CSIZE; // Mask the character size bits
    options.c_cflag |= CS8; // Select 8 data bits
    options.c_cflag &= ~PARENB; // No parity
    options.c_cflag &= ~CSTOPB; // 1 stop bit
    options.c_cflag &= ~CRTSCTS; // No hardware flow control

    options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); // Raw input
    options.c_iflag &= ~(IXON | IXOFF | IXANY); // No software flow control
    options.c_oflag &= ~OPOST; // Raw output

    if (tcsetattr(uartFd, TCSANOW, &options) != 0) {
        perror("Error setting UART attributes");
        close(uartFd);
        return -1;
    }

    return uartFd;
}

If the issue persists, please provide additional details such as the exact error message from perror and the device path you are using.

Please, also check if these links can help you solve your problem:

How to Use UART on Torizon OS | Toradex Developer Center.