include/linux/leds.h

   1 /*
   2  * Driver model for leds and led triggers
   3  *
   4  * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
   5  * Copyright (C) 2005 Richard Purdie <rpurdie@openedhand.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  */
  12 #ifndef __LINUX_LEDS_H_INCLUDED
  13 #define __LINUX_LEDS_H_INCLUDED
  14
  15 #include <linux/list.h>
  16 #include <linux/spinlock.h>
  17 #include <linux/rwsem.h>
  18
  19 struct device;
  20 /*
  21  * LED Core
  22  */
  23
  24 enum led_brightness {
  25         LED_OFF         = 0,
  26         LED_HALF        = 127,
  27         LED_FULL        = 255,
  28 };
  29
  30 struct led_classdev {
  31         const char              *name;
  32         int                      brightness;
  33         int                      max_brightness;
  34         int                      flags;
  35
  36         /* Lower 16 bits reflect status */
  37 #define LED_SUSPENDED           (1 << 0)
  38         /* Upper 16 bits reflect control information */
  39 #define LED_CORE_SUSPENDRESUME  (1 << 16)
  40
  41         /* Set LED brightness level */
  42         /* Must not sleep, use a workqueue if needed */
  43         void            (*brightness_set)(struct led_classdev *led_cdev,
  44                                           enum led_brightness brightness);
  45         /* Get LED brightness level */
  46         enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
  47
  48         /* Activate hardware accelerated blink, delays are in
  49          * miliseconds and if none is provided then a sensible default
  50          * should be chosen. The call can adjust the timings if it can't
  51          * match the values specified exactly. */
  52         int             (*blink_set)(struct led_classdev *led_cdev,
  53                                      unsigned long *delay_on,
  54                                      unsigned long *delay_off);
  55
  56         struct device           *dev;
  57         struct list_head         node;                  /* LED Device list */
  58         const char              *default_trigger;       /* Trigger to use */
  59
  60 #ifdef CONFIG_LEDS_TRIGGERS
  61         /* Protects the trigger data below */
  62         struct rw_semaphore      trigger_lock;
  63
  64         struct led_trigger      *trigger;
  65         struct list_head         trig_list;
  66         void                    *trigger_data;
  67 #endif
  68 };
  69
  70 extern int led_classdev_register(struct device *parent,
  71                                  struct led_classdev *led_cdev);
  72 extern void led_classdev_unregister(struct led_classdev *led_cdev);
  73 extern void led_classdev_suspend(struct led_classdev *led_cdev);
  74 extern void led_classdev_resume(struct led_classdev *led_cdev);
  75
  76 /*
  77  * LED Triggers
  78  */
  79 #ifdef CONFIG_LEDS_TRIGGERS
  80
  81 #define TRIG_NAME_MAX 50
  82
  83 struct led_trigger {
  84         /* Trigger Properties */
  85         const char       *name;
  86         void            (*activate)(struct led_classdev *led_cdev);
  87         void            (*deactivate)(struct led_classdev *led_cdev);
  88
  89         /* LEDs under control by this trigger (for simple triggers) */
  90         rwlock_t          leddev_list_lock;
  91         struct list_head  led_cdevs;
  92
  93         /* Link to next registered trigger */
  94         struct list_head  next_trig;
  95 };
  96
  97 /* Registration functions for complex triggers */
  98 extern int led_trigger_register(struct led_trigger *trigger);
  99 extern void led_trigger_unregister(struct led_trigger *trigger);
 100
 101 /* Registration functions for simple triggers */
 102 #define DEFINE_LED_TRIGGER(x)           static struct led_trigger *x;
 103 #define DEFINE_LED_TRIGGER_GLOBAL(x)    struct led_trigger *x;
 104 extern void led_trigger_register_simple(const char *name,
 105                                 struct led_trigger **trigger);
 106 extern void led_trigger_unregister_simple(struct led_trigger *trigger);
 107 extern void led_trigger_event(struct led_trigger *trigger,
 108                                 enum led_brightness event);
 109
 110 #else
 111
 112 /* Triggers aren't active - null macros */
 113 #define DEFINE_LED_TRIGGER(x)
 114 #define DEFINE_LED_TRIGGER_GLOBAL(x)
 115 #define led_trigger_register_simple(x, y) do {} while(0)
 116 #define led_trigger_unregister_simple(x) do {} while(0)
 117 #define led_trigger_event(x, y) do {} while(0)
 118
 119 #endif
 120
 121 /* Trigger specific functions */
 122 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
 123 extern void ledtrig_ide_activity(void);
 124 #else
 125 #define ledtrig_ide_activity() do {} while(0)
 126 #endif
 127
 128 /*
 129  * Generic LED platform data for describing LED names and default triggers.
 130  */
 131 struct led_info {
 132         const char      *name;
 133         const char      *default_trigger;
 134         int             flags;
 135 };
 136
 137 struct led_platform_data {
 138         int             num_leds;
 139         struct led_info *leds;
 140 };
 141
 142 /* For the leds-gpio driver */
 143 struct gpio_led {
 144         const char *name;
 145         const char *default_trigger;
 146         unsigned        gpio;
 147         unsigned        active_low : 1;
 148         unsigned        retain_state_suspended : 1;
 149         unsigned        default_state : 2;
 150         /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
 151 };
 152 #define LEDS_GPIO_DEFSTATE_OFF  0
 153 #define LEDS_GPIO_DEFSTATE_ON   1
 154 #define LEDS_GPIO_DEFSTATE_KEEP 2
 155
 156 struct gpio_led_platform_data {
 157         int             num_leds;
 158         struct gpio_led *leds;
 159         int             (*gpio_blink_set)(unsigned gpio,
 160                                         unsigned long *delay_on,
 161                                         unsigned long *delay_off);
 162 };
 163
 164
 165 #endif          /* __LINUX_LEDS_H_INCLUDED */