error: dm_mmc_ops undeclared (first use in this function)

Question

I'm constructing an u-boot bootloader for my embedded system (cyclone V) using Buildroot and I get the following error :

error: 'dm_mmc_ops' undeclared (first use in this function)

After several unsuccessful attempts to understand/solve the error, I've manage to isolate the problem which looks like the simple code hereafter and generates the same error :

File1.h

#ifndef FILE1
#define FILE1

struct dm_mmc_ops {
    int (*send_cmd)(int data);
    int (*set_ios)(char* dev);
};

struct dev {
    struct dm_mmc_ops* ops;
} *dev;

#define mmc_get_ops(dev)        ((dm_mmc_ops *)(dev)->ops)

#endif

File2.h

#ifndef FILE2
#define FILE2

#include "file1.h"

extern const struct dm_mmc_ops dm_dwmci_ops;

#endif

File2.c

#include <stdio.h>
#include "file1.h"
#include "file2.h"

int return_int (int data)
{
    return data;
}

int return_ptr (char* data)
{
    return (int) data;
}


const struct dm_mmc_ops dm_dwmci_ops = {
    .send_cmd   = return_int,
    .set_ios    = return_ptr
};

void main (void)
{
    struct dev my_dev = {.ops = &dm_dwmci_ops};
    dev = &my_dev;
    char text[] = "abcd";


    struct dm_mmc_ops *test_mmc = mmc_get_ops(dev);  // Error is here !!!

    printf("%d\n",test_mmc->send_cmd(50));
    printf("%d\n",text);
    printf("%d\n",test_mmc->set_ios(text));
    return;
}

Then the error generated is :

error: 'dm_mmc_ops' undeclared (first use in this function)

What is wrong in my code and what should I do to get rid of this error ?

Answer 1

Your problem is here

#define mmc_get_ops(dev)        ((dm_mmc_ops *)(dev)->ops)
                                  ^^^^^^^^^^

You probably want

#define mmc_get_ops(dev)        ((struct dm_mmc_ops *)(dev)->ops)

Besides that you have a number of other problems. Set you compiler to a high warning level (e.g. gcc -Wall ...) and then fix all warnings.