LXR linux/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#include <linux/timer.h>
  19#include <linux/workqueue.h>
  20
  21struct device;
  22/*
  23 * LED Core
  24 */
  25
  26enum led_brightness {
  27        LED_OFF         = 0,
  28        LED_HALF        = 127,
  29        LED_FULL        = 255,
  30};
  31
  32struct led_classdev {
  33        const char              *name;
  34        int                      brightness;
  35        int                      max_brightness;
  36        int                      flags;
  37
  38        /* Lower 16 bits reflect status */
  39#define LED_SUSPENDED           (1 << 0)
  40        /* Upper 16 bits reflect control information */
  41#define LED_CORE_SUSPENDRESUME  (1 << 16)
  42#define LED_BLINK_ONESHOT       (1 << 17)
  43#define LED_BLINK_ONESHOT_STOP  (1 << 18)
  44#define LED_BLINK_INVERT        (1 << 19)
  45
  46        /* Set LED brightness level */
  47        /* Must not sleep, use a workqueue if needed */
  48        void            (*brightness_set)(struct led_classdev *led_cdev,
  49                                          enum led_brightness brightness);
  50        /* Get LED brightness level */
  51        enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
  52
  53        /*
  54         * Activate hardware accelerated blink, delays are in milliseconds
  55         * and if both are zero then a sensible default should be chosen.
  56         * The call should adjust the timings in that case and if it can't
  57         * match the values specified exactly.
  58         * Deactivate blinking again when the brightness is set to a fixed
  59         * value via the brightness_set() callback.
  60         */
  61        int             (*blink_set)(struct led_classdev *led_cdev,
  62                                     unsigned long *delay_on,
  63                                     unsigned long *delay_off);
  64
  65        struct device           *dev;
  66        struct list_head         node;                  /* LED Device list */
  67        const char              *default_trigger;       /* Trigger to use */
  68
  69        unsigned long            blink_delay_on, blink_delay_off;
  70        struct timer_list        blink_timer;
  71        int                      blink_brightness;
  72
  73        struct work_struct      set_brightness_work;
  74        int                     delayed_set_value;
  75
  76#ifdef CONFIG_LEDS_TRIGGERS
  77        /* Protects the trigger data below */
  78        struct rw_semaphore      trigger_lock;
  79
  80        struct led_trigger      *trigger;
  81        struct list_head         trig_list;
  82        void                    *trigger_data;
  83        /* true if activated - deactivate routine uses it to do cleanup */
  84        bool                    activated;
  85#endif
  86};
  87
  88extern int led_classdev_register(struct device *parent,
  89                                 struct led_classdev *led_cdev);
  90extern void led_classdev_unregister(struct led_classdev *led_cdev);
  91extern void led_classdev_suspend(struct led_classdev *led_cdev);
  92extern void led_classdev_resume(struct led_classdev *led_cdev);
  93
  94/**
  95 * led_blink_set - set blinking with software fallback
  96 * @led_cdev: the LED to start blinking
  97 * @delay_on: the time it should be on (in ms)
  98 * @delay_off: the time it should ble off (in ms)
  99 *
 100 * This function makes the LED blink, attempting to use the
 101 * hardware acceleration if possible, but falling back to
 102 * software blinking if there is no hardware blinking or if
 103 * the LED refuses the passed values.
 104 *
 105 * Note that if software blinking is active, simply calling
 106 * led_cdev->brightness_set() will not stop the blinking,
 107 * use led_classdev_brightness_set() instead.
 108 */
 109extern void led_blink_set(struct led_classdev *led_cdev,
 110                          unsigned long *delay_on,
 111                          unsigned long *delay_off);
 112/**
 113 * led_blink_set_oneshot - do a oneshot software blink
 114 * @led_cdev: the LED to start blinking
 115 * @delay_on: the time it should be on (in ms)
 116 * @delay_off: the time it should ble off (in ms)
 117 * @invert: blink off, then on, leaving the led on
 118 *
 119 * This function makes the LED blink one time for delay_on +
 120 * delay_off time, ignoring the request if another one-shot
 121 * blink is already in progress.
 122 *
 123 * If invert is set, led blinks for delay_off first, then for
 124 * delay_on and leave the led on after the on-off cycle.
 125 */
 126extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
 127                                  unsigned long *delay_on,
 128                                  unsigned long *delay_off,
 129                                  int invert);
 130/**
 131 * led_set_brightness - set LED brightness
 132 * @led_cdev: the LED to set
 133 * @brightness: the brightness to set it to
 134 *
 135 * Set an LED's brightness, and, if necessary, cancel the
 136 * software blink timer that implements blinking when the
 137 * hardware doesn't.
 138 */
 139extern void led_set_brightness(struct led_classdev *led_cdev,
 140                               enum led_brightness brightness);
 141
 142/*
 143 * LED Triggers
 144 */
 145#ifdef CONFIG_LEDS_TRIGGERS
 146
 147#define TRIG_NAME_MAX 50
 148
 149struct led_trigger {
 150        /* Trigger Properties */
 151        const char       *name;
 152        void            (*activate)(struct led_classdev *led_cdev);
 153        void            (*deactivate)(struct led_classdev *led_cdev);
 154
 155        /* LEDs under control by this trigger (for simple triggers) */
 156        rwlock_t          leddev_list_lock;
 157        struct list_head  led_cdevs;
 158
 159        /* Link to next registered trigger */
 160        struct list_head  next_trig;
 161};
 162
 163/* Registration functions for complex triggers */
 164extern int led_trigger_register(struct led_trigger *trigger);
 165extern void led_trigger_unregister(struct led_trigger *trigger);
 166
 167/* Registration functions for simple triggers */
 168#define DEFINE_LED_TRIGGER(x)           static struct led_trigger *x;
 169#define DEFINE_LED_TRIGGER_GLOBAL(x)    struct led_trigger *x;
 170extern void led_trigger_register_simple(const char *name,
 171                                struct led_trigger **trigger);
 172extern void led_trigger_unregister_simple(struct led_trigger *trigger);
 173extern void led_trigger_event(struct led_trigger *trigger,
 174                                enum led_brightness event);
 175extern void led_trigger_blink(struct led_trigger *trigger,
 176                              unsigned long *delay_on,
 177                              unsigned long *delay_off);
 178extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
 179                                      unsigned long *delay_on,
 180                                      unsigned long *delay_off,
 181                                      int invert);
 182
 183#else
 184
 185/* Triggers aren't active - null macros */
 186#define DEFINE_LED_TRIGGER(x)
 187#define DEFINE_LED_TRIGGER_GLOBAL(x)
 188#define led_trigger_register_simple(x, y) do {} while(0)
 189#define led_trigger_unregister_simple(x) do {} while(0)
 190#define led_trigger_event(x, y) do {} while(0)
 191
 192#endif
 193
 194/* Trigger specific functions */
 195#ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
 196extern void ledtrig_ide_activity(void);
 197#else
 198#define ledtrig_ide_activity() do {} while(0)
 199#endif
 200
 201/*
 202 * Generic LED platform data for describing LED names and default triggers.
 203 */
 204struct led_info {
 205        const char      *name;
 206        const char      *default_trigger;
 207        int             flags;
 208};
 209
 210struct led_platform_data {
 211        int             num_leds;
 212        struct led_info *leds;
 213};
 214
 215/* For the leds-gpio driver */
 216struct gpio_led {
 217        const char *name;
 218        const char *default_trigger;
 219        unsigned        gpio;
 220        unsigned        active_low : 1;
 221        unsigned        retain_state_suspended : 1;
 222        unsigned        default_state : 2;
 223        /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
 224};
 225#define LEDS_GPIO_DEFSTATE_OFF          0
 226#define LEDS_GPIO_DEFSTATE_ON           1
 227#define LEDS_GPIO_DEFSTATE_KEEP         2
 228
 229struct gpio_led_platform_data {
 230        int             num_leds;
 231        const struct gpio_led *leds;
 232
 233#define GPIO_LED_NO_BLINK_LOW   0       /* No blink GPIO state low */
 234#define GPIO_LED_NO_BLINK_HIGH  1       /* No blink GPIO state high */
 235#define GPIO_LED_BLINK          2       /* Please, blink */
 236        int             (*gpio_blink_set)(unsigned gpio, int state,
 237                                        unsigned long *delay_on,
 238                                        unsigned long *delay_off);
 239};
 240
 241struct platform_device *gpio_led_register_device(
 242                int id, const struct gpio_led_platform_data *pdata);
 243
 244enum cpu_led_event {
 245        CPU_LED_IDLE_START,     /* CPU enters idle */
 246        CPU_LED_IDLE_END,       /* CPU idle ends */
 247        CPU_LED_START,          /* Machine starts, especially resume */
 248        CPU_LED_STOP,           /* Machine stops, especially suspend */
 249        CPU_LED_HALTED,         /* Machine shutdown */
 250};
 251#ifdef CONFIG_LEDS_TRIGGER_CPU
 252extern void ledtrig_cpu(enum cpu_led_event evt);
 253#else
 254static inline void ledtrig_cpu(enum cpu_led_event evt)
 255{
 256        return;
 257}
 258#endif
 259
 260#endif          /* __LINUX_LEDS_H_INCLUDED */
 261