#ifndef __LINUX_GPIO_H
  #define __LINUX_GPIO_H
  
  /* see Documentation/gpio.txt */

  /* make these flag values available regardless of GPIO kconfig options */
  #define GPIOF_DIR_OUT	(0 << 0)
  #define GPIOF_DIR_IN	(1 << 0)
  
  #define GPIOF_INIT_LOW	(0 << 1)
  #define GPIOF_INIT_HIGH	(1 << 1)
  
  #define GPIOF_IN		(GPIOF_DIR_IN)
  #define GPIOF_OUT_INIT_LOW	(GPIOF_DIR_OUT | GPIOF_INIT_LOW)
  #define GPIOF_OUT_INIT_HIGH	(GPIOF_DIR_OUT | GPIOF_INIT_HIGH)

  /**
   * struct gpio - a structure describing a GPIO with configuration
   * @gpio:	the GPIO number
   * @flags:	GPIO configuration as specified by GPIOF_*
   * @label:	a literal description string of this GPIO
   */
  struct gpio {
  	unsigned	gpio;
  	unsigned long	flags;
  	const char	*label;
  };

  #ifdef CONFIG_GENERIC_GPIO
  #include <asm/gpio.h>
  
  #else

  #include <linux/kernel.h>

  #include <linux/types.h>
  #include <linux/errno.h>

  struct device;

  struct gpio_chip;

  static inline bool gpio_is_valid(int number)

  {

  	return false;

  }

  static inline int gpio_request(unsigned gpio, const char *label)

  {
  	return -ENOSYS;
  }

  static inline int gpio_request_one(unsigned gpio,

  					unsigned long flags, const char *label)
  {
  	return -ENOSYS;
  }

  static inline int gpio_request_array(const struct gpio *array, size_t num)

  {
  	return -ENOSYS;
  }

  static inline void gpio_free(unsigned gpio)
  {

  	might_sleep();

  	/* GPIO can never have been requested */
  	WARN_ON(1);
  }

  static inline void gpio_free_array(const struct gpio *array, size_t num)

  {
  	might_sleep();
  
  	/* GPIO can never have been requested */
  	WARN_ON(1);
  }

  static inline int gpio_direction_input(unsigned gpio)

  {
  	return -ENOSYS;
  }

  static inline int gpio_direction_output(unsigned gpio, int value)

  {
  	return -ENOSYS;
  }

  static inline int gpio_set_debounce(unsigned gpio, unsigned debounce)
  {
  	return -ENOSYS;
  }

  static inline int gpio_get_value(unsigned gpio)
  {
  	/* GPIO can never have been requested or set as {in,out}put */
  	WARN_ON(1);
  	return 0;
  }
  
  static inline void gpio_set_value(unsigned gpio, int value)
  {
  	/* GPIO can never have been requested or set as output */
  	WARN_ON(1);
  }
  
  static inline int gpio_cansleep(unsigned gpio)
  {
  	/* GPIO can never have been requested or set as {in,out}put */
  	WARN_ON(1);
  	return 0;
  }
  
  static inline int gpio_get_value_cansleep(unsigned gpio)
  {
  	/* GPIO can never have been requested or set as {in,out}put */
  	WARN_ON(1);
  	return 0;
  }
  
  static inline void gpio_set_value_cansleep(unsigned gpio, int value)
  {
  	/* GPIO can never have been requested or set as output */
  	WARN_ON(1);
  }

  static inline int gpio_export(unsigned gpio, bool direction_may_change)
  {
  	/* GPIO can never have been requested or set as {in,out}put */
  	WARN_ON(1);
  	return -EINVAL;
  }

  static inline int gpio_export_link(struct device *dev, const char *name,
  				unsigned gpio)
  {
  	/* GPIO can never have been exported */
  	WARN_ON(1);
  	return -EINVAL;
  }

  static inline int gpio_sysfs_set_active_low(unsigned gpio, int value)
  {
  	/* GPIO can never have been requested */
  	WARN_ON(1);
  	return -EINVAL;
  }

  static inline void gpio_unexport(unsigned gpio)
  {
  	/* GPIO can never have been exported */
  	WARN_ON(1);
  }

  static inline int gpio_to_irq(unsigned gpio)
  {
  	/* GPIO can never have been requested or set as input */
  	WARN_ON(1);
  	return -EINVAL;
  }
  
  static inline int irq_to_gpio(unsigned irq)
  {
  	/* irq can never have been returned from gpio_to_irq() */
  	WARN_ON(1);
  	return -EINVAL;
  }
  
  #endif
  
  #endif /* __LINUX_GPIO_H */