// Copyright (c) 2014 Adafruit Industries

// Author: Tony DiCola

// Based on code from Gert van Loo & Dom: http://elinux.org/RPi_Low-level_peripherals#GPIO_Code_examples

// Permission is hereby granted, free of charge, to any person obtaining a copy

// of this software and associated documentation files (the "Software"), to deal

// in the Software without restriction, including without limitation the rights

// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

// copies of the Software, and to permit persons to whom the Software is

// furnished to do so, subject to the following conditions:

// The above copyright notice and this permission notice shall be included in all

// copies or substantial portions of the Software.

// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE

// SOFTWARE.

// Simple fast memory-mapped GPIO library for the Raspberry Pi.

#ifndef PI_2_MMIO_H

#define PI_2_MMIO_H

#include <stdint.h>

#define MMIO_SUCCESS 0

#define MMIO_ERROR_DEVMEM -1

#define MMIO_ERROR_MMAP -2

#define MMIO_ERROR_OFFSET -3

volatile uint32_t* pi_2_mmio_gpio;

int pi_2_mmio_init(void);

static inline void pi_2_mmio_set_input(const int gpio_number) {

  // Set GPIO register to 000 for specified GPIO number.

  *(pi_2_mmio_gpio+((gpio_number)/10)) &= ~(7<<(((gpio_number)%10)*3));

}

static inline void pi_2_mmio_set_output(const int gpio_number) {

  // First set to 000 using input function.

  pi_2_mmio_set_input(gpio_number);

  // Next set bit 0 to 1 to set output.

  *(pi_2_mmio_gpio+((gpio_number)/10)) |=  (1<<(((gpio_number)%10)*3));

}

static inline void pi_2_mmio_set_high(const int gpio_number) {

  *(pi_2_mmio_gpio+7) = 1 << gpio_number;

}

static inline void pi_2_mmio_set_low(const int gpio_number) {

  *(pi_2_mmio_gpio+10) = 1 << gpio_number;

}

static inline uint32_t pi_2_mmio_input(const int gpio_number) {

  return *(pi_2_mmio_gpio+13) & (1 << gpio_number);

}

#endif