why when implement interrupt handler in qt give beolw error ? How to resolve it ?

[JonB]

@jsulm
From the error message (aka void ()()) and from looking at definitions of interrupt_handler_t on the web I do not think that is so. It seems to be

typedef void @far (*interrupt_handler_t)(void);

This is beyond my expertise of C++ now, but is there a problem with passing a C++ member function here??

[jsulm]

@JonB @Qt-embedded-developer I don't think a method can be used here as interrupt handler. @Qt-embedded-developer use a normal function and call your MainWindow there (also, it is strange that MainWindow handles interrupts).

[Qt embedded developer]

@jsulm said in why when implement interrupt handler in qt give beolw error ? How to resolve it ?:

interrupt_handler_t

This 3 thing is related to your question and my 2nd error.

1] in source.h
static interrupt_handler_t interrupt_handler;

2] in source.c
typedef void (*interrupt_handler_t)(void) ;

3] in source.c

int32_t ST25DV_GPO_interrupt_init(interrupt_handler_t fh)
{
    pthread_t intr_thread;
    struct sched_param params;
    int ret;

    if(fh == NULL)
    {
        fprintf(stderr,"Handler is not set\r\n");
        return ERR_PARAM;
    }
    interrupt_handler = fh;

    /* create a pthread to poll for interrupt */
    ret = pthread_create(&intr_thread, NULL, ST25DV_GPO_pthread_func, NULL);
    if (ret) {
        fprintf(stderr, "Error: poll thread creation %d\r\n", ret);
        return ERR_IO;
    }

    /* Assign highest priority to polling thread */
    params.sched_priority = sched_get_priority_max(SCHED_FIFO);
    ret = pthread_setschedparam(intr_thread, SCHED_FIFO, &params);
    if (ret) {
        fprintf(stderr,"Error: assigning high priority to polling thread\r\n");
        return ERR_IO;
    }

    return ERR_NONE;
}

[jsulm]

@Qt-embedded-developer said in why when implement interrupt handler in qt give beolw error ? How to resolve it ?:

typedef void (*interrupt_handler_t)(void) ;

This is a function pointer type, not a pointer to a method, so you can't use a method as interrupt handler. Use a normal function.

[JonB]

@jsulm said in why when implement interrupt handler in qt give beolw error ? How to resolve it ?:

This is a function pointer type, not a pointer to a method

This is kind of what I thought/asked you.

I am not familiar with this distinction between "a function pointer type" versus "a pointer to a method". Could you explain, or point me to a description, please?

EDIT
Ah, is this to do with class (non-static) method will need an instance and of course that is not appropriate here?

[jsulm]

@JonB Well, method pointers are funny:

typedef void (MainWindow::*MethodPointer)();
MethodPointer p = &MainWindow::doSomething;
// Calling
(this->*p)();

[jsulm]

@JonB said in why when implement interrupt handler in qt give beolw error ? How to resolve it ?:

Ah, is this to do with class (non-static) method will need an instance and of course that is not appropriate here?

Yes, you need an instance.

[JonB]

@jsulm
I did a Google and came up with https://isocpp.org/wiki/faq/pointers-to-members#fnptr-vs-memfnptr-types

Is the type of “pointer-to-member-function” different from “pointer-to-function”?
Yep.

Consider the following function:

int f(char a, float b);
The type of this function is different depending on whether it is an ordinary function or a non-static member function of some class:

Its type is “int ()(char,float)” if an ordinary function
Its type is “int (Fred::)(char,float)” if a non-static member function of class Fred
Note: if it’s a static member function of class Fred, its type is the same as if it were an ordinary function: “int (*)(char,float)”.

Separately:

Yes, you need an instance.

Yes, that's kind of a different issue, in that it's not going to work anyway for the OP. But I was concentrating on the compiler error message.

[Qt embedded developer]

@JonB So How to implement the interrupt handler for any i2c device using qt ?

[jsulm]

@Qt-embedded-developer Use a normal function as interrupt handler, not a method in a class. In that function you can then call methods of your class if you need to do so.