1 /* 2 * Driver model for leds and led triggers 3 * 4 * Copyright (C) 2005 John Lenz <[email protected]> 5 * Copyright (C) 2005 Richard Purdie <[email protected]> 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 /* true if activated - deactivate routine uses it to do cleanup */ 77 bool activated; 78 #endif 79 }; 80 81 extern int led_classdev_register(struct device *parent, 82 struct led_classdev *led_cdev); 83 extern void led_classdev_unregister(struct led_classdev *led_cdev); 84 extern void led_classdev_suspend(struct led_classdev *led_cdev); 85 extern void led_classdev_resume(struct led_classdev *led_cdev); 86 87 /** 88 * led_blink_set - set blinking with software fallback 89 * @led_cdev: the LED to start blinking 90 * @delay_on: the time it should be on (in ms) 91 * @delay_off: the time it should ble off (in ms) 92 * 93 * This function makes the LED blink, attempting to use the 94 * hardware acceleration if possible, but falling back to 95 * software blinking if there is no hardware blinking or if 96 * the LED refuses the passed values. 97 * 98 * Note that if software blinking is active, simply calling 99 * led_cdev->brightness_set() will not stop the blinking, 100 * use led_classdev_brightness_set() instead. 101 */ 102 extern void led_blink_set(struct led_classdev *led_cdev, 103 unsigned long *delay_on, 104 unsigned long *delay_off); 105 /** 106 * led_brightness_set - set LED brightness 107 * @led_cdev: the LED to set 108 * @brightness: the brightness to set it to 109 * 110 * Set an LED's brightness, and, if necessary, cancel the 111 * software blink timer that implements blinking when the 112 * hardware doesn't. 113 */ 114 extern void led_brightness_set(struct led_classdev *led_cdev, 115 enum led_brightness brightness); 116 117 /* 118 * LED Triggers 119 */ 120 #ifdef CONFIG_LEDS_TRIGGERS 121 122 #define TRIG_NAME_MAX 50 123 124 struct led_trigger { 125 /* Trigger Properties */ 126 const char *name; 127 void (*activate)(struct led_classdev *led_cdev); 128 void (*deactivate)(struct led_classdev *led_cdev); 129 130 /* LEDs under control by this trigger (for simple triggers) */ 131 rwlock_t leddev_list_lock; 132 struct list_head led_cdevs; 133 134 /* Link to next registered trigger */ 135 struct list_head next_trig; 136 }; 137 138 /* Registration functions for complex triggers */ 139 extern int led_trigger_register(struct led_trigger *trigger); 140 extern void led_trigger_unregister(struct led_trigger *trigger); 141 142 /* Registration functions for simple triggers */ 143 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x; 144 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x; 145 extern void led_trigger_register_simple(const char *name, 146 struct led_trigger **trigger); 147 extern void led_trigger_unregister_simple(struct led_trigger *trigger); 148 extern void led_trigger_event(struct led_trigger *trigger, 149 enum led_brightness event); 150 extern void led_trigger_blink(struct led_trigger *trigger, 151 unsigned long *delay_on, 152 unsigned long *delay_off); 153 154 #else 155 156 /* Triggers aren't active - null macros */ 157 #define DEFINE_LED_TRIGGER(x) 158 #define DEFINE_LED_TRIGGER_GLOBAL(x) 159 #define led_trigger_register_simple(x, y) do {} while(0) 160 #define led_trigger_unregister_simple(x) do {} while(0) 161 #define led_trigger_event(x, y) do {} while(0) 162 163 #endif 164 165 /* Trigger specific functions */ 166 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK 167 extern void ledtrig_ide_activity(void); 168 #else 169 #define ledtrig_ide_activity() do {} while(0) 170 #endif 171 172 /* 173 * Generic LED platform data for describing LED names and default triggers. 174 */ 175 struct led_info { 176 const char *name; 177 const char *default_trigger; 178 int flags; 179 }; 180 181 struct led_platform_data { 182 int num_leds; 183 struct led_info *leds; 184 }; 185 186 /* For the leds-gpio driver */ 187 struct gpio_led { 188 const char *name; 189 const char *default_trigger; 190 unsigned gpio; 191 unsigned active_low : 1; 192 unsigned retain_state_suspended : 1; 193 unsigned default_state : 2; 194 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ 195 }; 196 #define LEDS_GPIO_DEFSTATE_OFF 0 197 #define LEDS_GPIO_DEFSTATE_ON 1 198 #define LEDS_GPIO_DEFSTATE_KEEP 2 199 200 struct gpio_led_platform_data { 201 int num_leds; 202 const struct gpio_led *leds; 203 204 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */ 205 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */ 206 #define GPIO_LED_BLINK 2 /* Please, blink */ 207 int (*gpio_blink_set)(unsigned gpio, int state, 208 unsigned long *delay_on, 209 unsigned long *delay_off); 210 }; 211 212 struct platform_device *gpio_led_register_device( 213 int id, const struct gpio_led_platform_data *pdata); 214 215 #endif /* __LINUX_LEDS_H_INCLUDED */ 216