/*
   * Driver model for leds and led triggers
   *
   * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
   * Copyright (C) 2005 Richard Purdie <rpurdie@openedhand.com>
   *
   * This program is free software; you can redistribute it and/or modify
   * it under the terms of the GNU General Public License version 2 as
   * published by the Free Software Foundation.
   *
   */
  #ifndef __LINUX_LEDS_H_INCLUDED
  #define __LINUX_LEDS_H_INCLUDED

  #include <linux/list.h>

  #include <linux/spinlock.h>

  #include <linux/rwsem.h>

  #include <linux/timer.h>

  struct device;

  /*
   * LED Core
   */
  
  enum led_brightness {

  	LED_OFF		= 0,
  	LED_HALF	= 127,
  	LED_FULL	= 255,

  };
  
  struct led_classdev {

  	const char		*name;
  	int			 brightness;

  	int			 max_brightness;

  	int			 flags;

  	/* Lower 16 bits reflect status */

  #define LED_SUSPENDED		(1 << 0)

  	/* Upper 16 bits reflect control information */
  #define LED_CORE_SUSPENDRESUME	(1 << 16)

  	/* Set LED brightness level */

  	/* Must not sleep, use a workqueue if needed */

  	void		(*brightness_set)(struct led_classdev *led_cdev,
  					  enum led_brightness brightness);

  	/* Get LED brightness level */
  	enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);

  	/*
  	 * Activate hardware accelerated blink, delays are in milliseconds
  	 * and if both are zero then a sensible default should be chosen.
  	 * The call should adjust the timings in that case and if it can't
  	 * match the values specified exactly.
  	 * Deactivate blinking again when the brightness is set to a fixed
  	 * value via the brightness_set() callback.
  	 */

  	int		(*blink_set)(struct led_classdev *led_cdev,
  				     unsigned long *delay_on,
  				     unsigned long *delay_off);

  	struct device		*dev;

  	struct list_head	 node;			/* LED Device list */

  	const char		*default_trigger;	/* Trigger to use */

  	unsigned long		 blink_delay_on, blink_delay_off;
  	struct timer_list	 blink_timer;
  	int			 blink_brightness;

  #ifdef CONFIG_LEDS_TRIGGERS

  	/* Protects the trigger data below */

  	struct rw_semaphore	 trigger_lock;

  	struct led_trigger	*trigger;
  	struct list_head	 trig_list;
  	void			*trigger_data;

  #endif

  };
  
  extern int led_classdev_register(struct device *parent,

  				 struct led_classdev *led_cdev);

  extern void led_classdev_unregister(struct led_classdev *led_cdev);

  extern void led_classdev_suspend(struct led_classdev *led_cdev);
  extern void led_classdev_resume(struct led_classdev *led_cdev);

  /**
   * led_blink_set - set blinking with software fallback
   * @led_cdev: the LED to start blinking
   * @delay_on: the time it should be on (in ms)
   * @delay_off: the time it should ble off (in ms)
   *
   * This function makes the LED blink, attempting to use the
   * hardware acceleration if possible, but falling back to
   * software blinking if there is no hardware blinking or if
   * the LED refuses the passed values.
   *
   * Note that if software blinking is active, simply calling
   * led_cdev->brightness_set() will not stop the blinking,
   * use led_classdev_brightness_set() instead.
   */
  extern void led_blink_set(struct led_classdev *led_cdev,
  			  unsigned long *delay_on,
  			  unsigned long *delay_off);
  /**
   * led_brightness_set - set LED brightness
   * @led_cdev: the LED to set
   * @brightness: the brightness to set it to
   *
   * Set an LED's brightness, and, if necessary, cancel the
   * software blink timer that implements blinking when the
   * hardware doesn't.
   */
  extern void led_brightness_set(struct led_classdev *led_cdev,
  			       enum led_brightness brightness);

  /*
   * LED Triggers
   */
  #ifdef CONFIG_LEDS_TRIGGERS
  
  #define TRIG_NAME_MAX 50
  
  struct led_trigger {
  	/* Trigger Properties */

  	const char	 *name;
  	void		(*activate)(struct led_classdev *led_cdev);
  	void		(*deactivate)(struct led_classdev *led_cdev);

  
  	/* LEDs under control by this trigger (for simple triggers) */

  	rwlock_t	  leddev_list_lock;
  	struct list_head  led_cdevs;

  
  	/* Link to next registered trigger */

  	struct list_head  next_trig;

  };
  
  /* Registration functions for complex triggers */
  extern int led_trigger_register(struct led_trigger *trigger);
  extern void led_trigger_unregister(struct led_trigger *trigger);
  
  /* Registration functions for simple triggers */
  #define DEFINE_LED_TRIGGER(x)		static struct led_trigger *x;
  #define DEFINE_LED_TRIGGER_GLOBAL(x)	struct led_trigger *x;
  extern void led_trigger_register_simple(const char *name,
  				struct led_trigger **trigger);
  extern void led_trigger_unregister_simple(struct led_trigger *trigger);
  extern void led_trigger_event(struct led_trigger *trigger,
  				enum led_brightness event);

  extern void led_trigger_blink(struct led_trigger *trigger,
  			      unsigned long *delay_on,
  			      unsigned long *delay_off);

  
  #else
  
  /* Triggers aren't active - null macros */
  #define DEFINE_LED_TRIGGER(x)
  #define DEFINE_LED_TRIGGER_GLOBAL(x)
  #define led_trigger_register_simple(x, y) do {} while(0)
  #define led_trigger_unregister_simple(x) do {} while(0)
  #define led_trigger_event(x, y) do {} while(0)
  
  #endif

  
  /* Trigger specific functions */
  #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
  extern void ledtrig_ide_activity(void);
  #else
  #define ledtrig_ide_activity() do {} while(0)
  #endif

  /*
   * Generic LED platform data for describing LED names and default triggers.
   */
  struct led_info {
  	const char	*name;

  	const char	*default_trigger;

  	int		flags;
  };
  
  struct led_platform_data {
  	int		num_leds;
  	struct led_info	*leds;
  };

  /* For the leds-gpio driver */
  struct gpio_led {
  	const char *name;

  	const char *default_trigger;

  	unsigned 	gpio;

  	unsigned	active_low : 1;
  	unsigned	retain_state_suspended : 1;
  	unsigned	default_state : 2;
  	/* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */

  };

  #define LEDS_GPIO_DEFSTATE_OFF		0
  #define LEDS_GPIO_DEFSTATE_ON		1
  #define LEDS_GPIO_DEFSTATE_KEEP		2

  
  struct gpio_led_platform_data {
  	int 		num_leds;

  	const struct gpio_led *leds;

  
  #define GPIO_LED_NO_BLINK_LOW	0	/* No blink GPIO state low */
  #define GPIO_LED_NO_BLINK_HIGH	1	/* No blink GPIO state high */

  #define GPIO_LED_BLINK		2	/* Please, blink */

  	int		(*gpio_blink_set)(unsigned gpio, int state,

  					unsigned long *delay_on,
  					unsigned long *delay_off);

  };

  struct platform_device *gpio_led_register_device(
  		int id, const struct gpio_led_platform_data *pdata);

  #endif		/* __LINUX_LEDS_H_INCLUDED */