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