File content as of revision 182:57724642e740:

/* mbed Microcontroller Library
 * Copyright (c) 2015-2016 Nuvoton
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "gpio_api.h"
#include "mbed_assert.h"
#include "pinmap.h"
#include "mbed_error.h"
#include "PeripheralPins.h"

uint32_t gpio_set(PinName pin)
{
    if (pin == (PinName) NC) {
        return 0;
    }

    uint32_t pin_index = NU_PINNAME_TO_PIN(pin);

#if 1
    pin_function(pin, 0 << NU_MFP_POS(pin_index));
#else
    pinmap_pinout(pin, PinMap_GPIO);
#endif

    return (uint32_t)(1 << pin_index);    // Return the pin mask
}

int gpio_is_connected(const gpio_t *obj)
{
    return (obj->pin != (PinName) NC);
}

void gpio_init(gpio_t *obj, PinName pin)
{
    obj->pin = pin;

    if (obj->pin == (PinName) NC) {
        return;
    }

    obj->mask = gpio_set(pin);
}

void gpio_mode(gpio_t *obj, PinMode mode)
{
    if (obj->pin == (PinName) NC) {
        return;
    }

    pin_mode(obj->pin, mode);
}

void gpio_dir(gpio_t *obj, PinDirection direction)
{
    if (obj->pin == (PinName) NC) {
        return;
    }

    uint32_t pin_index = NU_PINNAME_TO_PIN(obj->pin);
    uint32_t port_index = NU_PINNAME_TO_PORT(obj->pin);
    GPIO_T *gpio_base = NU_PORT_BASE(port_index);

    uint32_t mode_intern = GPIO_MODE_INPUT;

    switch (direction) {
    case PIN_INPUT:
        mode_intern = GPIO_MODE_INPUT;
        break;

    case PIN_OUTPUT:
        mode_intern = GPIO_MODE_OUTPUT;
        break;

    default:
        return;
    }

    GPIO_SetMode(gpio_base, 1 << pin_index, mode_intern);
}