/*
   * OF helpers for the GPIO API
   *
   * Copyright (c) 2007-2008  MontaVista Software, Inc.
   *
   * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License as published by
   * the Free Software Foundation; either version 2 of the License, or
   * (at your option) any later version.
   */
  
  #ifndef __LINUX_OF_GPIO_H
  #define __LINUX_OF_GPIO_H

  #include <linux/compiler.h>
  #include <linux/kernel.h>

  #include <linux/errno.h>

  #include <linux/gpio.h>

  #include <linux/of.h>

  struct device_node;
  
  /*
   * This is Linux-specific flags. By default controllers' and Linux' mapping
   * match, but GPIO controllers are free to translate their own flags to
   * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.
   */
  enum of_gpio_flags {
  	OF_GPIO_ACTIVE_LOW = 0x1,
  };

  #ifdef CONFIG_OF_GPIO
  
  /*

   * OF GPIO chip for memory mapped banks
   */
  struct of_mm_gpio_chip {

  	struct gpio_chip gc;

  	void (*save_regs)(struct of_mm_gpio_chip *mm_gc);
  	void __iomem *regs;
  };
  
  static inline struct of_mm_gpio_chip *to_of_mm_gpio_chip(struct gpio_chip *gc)
  {

  	return container_of(gc, struct of_mm_gpio_chip, gc);

  }

  extern int of_get_named_gpio_flags(struct device_node *np,
  		const char *list_name, int index, enum of_gpio_flags *flags);

  extern unsigned int of_gpio_count(struct device_node *np);

  extern int of_mm_gpiochip_add(struct device_node *np,
  			      struct of_mm_gpio_chip *mm_gc);

  extern void of_gpiochip_add(struct gpio_chip *gc);
  extern void of_gpiochip_remove(struct gpio_chip *gc);

  extern struct gpio_chip *of_node_to_gpiochip(struct device_node *np);

  extern int of_gpio_simple_xlate(struct gpio_chip *gc,
  				const struct of_phandle_args *gpiospec,
  				u32 *flags);

  #else /* CONFIG_OF_GPIO */

  
  /* Drivers may not strictly depend on the GPIO support, so let them link. */

  static inline int of_get_named_gpio_flags(struct device_node *np,
  		const char *list_name, int index, enum of_gpio_flags *flags)

  {
  	return -ENOSYS;
  }

  static inline unsigned int of_gpio_count(struct device_node *np)
  {
  	return 0;
  }

  static inline int of_gpio_simple_xlate(struct gpio_chip *gc,

  				       const struct of_phandle_args *gpiospec,
  				       u32 *flags)

  {
  	return -ENOSYS;
  }

  static inline void of_gpiochip_add(struct gpio_chip *gc) { }
  static inline void of_gpiochip_remove(struct gpio_chip *gc) { }

  #endif /* CONFIG_OF_GPIO */

  /**

   * of_get_gpio_flags() - Get a GPIO number and flags to use with GPIO API
   * @np:		device node to get GPIO from
   * @index:	index of the GPIO
   * @flags:	a flags pointer to fill in
   *
   * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
   * value on the error condition. If @flags is not NULL the function also fills
   * in flags for the GPIO.
   */
  static inline int of_get_gpio_flags(struct device_node *np, int index,
  		      enum of_gpio_flags *flags)
  {
  	return of_get_named_gpio_flags(np, "gpios", index, flags);
  }
  
  /**
   * of_get_named_gpio() - Get a GPIO number to use with GPIO API
   * @np:		device node to get GPIO from
   * @propname:	Name of property containing gpio specifier(s)
   * @index:	index of the GPIO
   *
   * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
   * value on the error condition.
   */
  static inline int of_get_named_gpio(struct device_node *np,
                                     const char *propname, int index)
  {
  	return of_get_named_gpio_flags(np, propname, index, NULL);
  }
  
  /**
   * of_get_gpio() - Get a GPIO number to use with GPIO API

   * @np:		device node to get GPIO from
   * @index:	index of the GPIO
   *
   * Returns GPIO number to use with Linux generic GPIO API, or one of the errno
   * value on the error condition.
   */
  static inline int of_get_gpio(struct device_node *np, int index)
  {
  	return of_get_gpio_flags(np, index, NULL);
  }

  #endif /* __LINUX_OF_GPIO_H */