int
libsoc_gpio_free (gpio * gpio)
{
char tmp_str[STR_BUF];
int fd;
if (gpio == NULL)
{
libsoc_gpio_debug (__func__, -1, "invalid gpio pointer");
return EXIT_FAILURE;
}
libsoc_gpio_debug (__func__, gpio->gpio, "freeing gpio");
if (gpio->callback != NULL)
{
printf ("Freeing callback!\n");
// Turn off the callback if there is one enabled
libsoc_gpio_callback_interrupt_cancel (gpio);
}
if (file_close (gpio->value_fd) < 0)
return EXIT_FAILURE;
if (gpio->shared == 1)
{
free (gpio);
return EXIT_SUCCESS;
}
fd = file_open ("/sys/class/gpio/unexport", O_SYNC | O_WRONLY);
if (fd < 0)
return EXIT_FAILURE;
sprintf (tmp_str, "%d", gpio->gpio);
if (file_write (fd, tmp_str, STR_BUF) < 0)
return EXIT_FAILURE;
if (file_close (fd) < 0)
return EXIT_FAILURE;
sprintf (tmp_str, "/sys/class/gpio/gpio%d", gpio->gpio);
if (file_valid (tmp_str))
{
libsoc_gpio_debug (__func__, gpio->gpio, "freeing failed");
return EXIT_FAILURE;
}
free (gpio);
return EXIT_SUCCESS;
}
int main(void) {
// Enable debug output
libsoc_set_debug(1);
// Request gpios
gpio_output = libsoc_gpio_request(GPIO_OUTPUT, LS_SHARED);
gpio_input = libsoc_gpio_request(GPIO_INPUT, LS_SHARED);
// Set direction to OUTPUT
libsoc_gpio_set_direction(gpio_output, OUTPUT);
// Set direction to INPUT
libsoc_gpio_set_direction(gpio_input, INPUT);
// Set edge to BOTH
libsoc_gpio_set_edge(gpio_input, BOTH);
// Setup callback
libsoc_gpio_callback_interrupt(gpio_input, &callback_test,
(void*) &interrupt_count);
printf("Push the button...\n");
// Disaple debug output so the code will respond faster
libsoc_set_debug(0);
sleep(10);
libsoc_set_debug(1);
// Cancel the callback on interrupt
libsoc_gpio_callback_interrupt_cancel(gpio_input);
//If gpio_request was successful
if (gpio_input) { // Free gpio request memory
libsoc_gpio_free(gpio_input);
}
if (gpio_output) { // Free gpio request memory
libsoc_gpio_free(gpio_output);
}
return EXIT_SUCCESS;
}