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