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/device.h> 16#include <linux/list.h> 17#include <linux/mutex.h> 18#include <linux/rwsem.h> 19#include <linux/spinlock.h> 20#include <linux/timer.h> 21#include <linux/workqueue.h> 22 23struct device; 24/* 25 * LED Core 26 */ 27 28enum led_brightness { 29 LED_OFF = 0, 30 LED_HALF = 127, 31 LED_FULL = 255, 32}; 33 34struct led_classdev { 35 const char *name; 36 enum led_brightness brightness; 37 enum led_brightness max_brightness; 38 int flags; 39 40 /* Lower 16 bits reflect status */ 41#define LED_SUSPENDED (1 << 0) 42 /* Upper 16 bits reflect control information */ 43#define LED_CORE_SUSPENDRESUME (1 << 16) 44#define LED_BLINK_ONESHOT (1 << 17) 45#define LED_BLINK_ONESHOT_STOP (1 << 18) 46#define LED_BLINK_INVERT (1 << 19) 47#define LED_SYSFS_DISABLE (1 << 20) 48#define SET_BRIGHTNESS_ASYNC (1 << 21) 49#define SET_BRIGHTNESS_SYNC (1 << 22) 50#define LED_DEV_CAP_FLASH (1 << 23) 51 52 /* Set LED brightness level */ 53 /* Must not sleep, use a workqueue if needed */ 54 void (*brightness_set)(struct led_classdev *led_cdev, 55 enum led_brightness brightness); 56 /* 57 * Set LED brightness level immediately - it can block the caller for 58 * the time required for accessing a LED device register. 59 */ 60 int (*brightness_set_sync)(struct led_classdev *led_cdev, 61 enum led_brightness brightness); 62 /* Get LED brightness level */ 63 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev); 64 65 /* 66 * Activate hardware accelerated blink, delays are in milliseconds 67 * and if both are zero then a sensible default should be chosen. 68 * The call should adjust the timings in that case and if it can't 69 * match the values specified exactly. 70 * Deactivate blinking again when the brightness is set to a fixed 71 * value via the brightness_set() callback. 72 */ 73 int (*blink_set)(struct led_classdev *led_cdev, 74 unsigned long *delay_on, 75 unsigned long *delay_off); 76 77 struct device *dev; 78 const struct attribute_group **groups; 79 80 struct list_head node; /* LED Device list */ 81 const char *default_trigger; /* Trigger to use */ 82 83 unsigned long blink_delay_on, blink_delay_off; 84 struct timer_list blink_timer; 85 int blink_brightness; 86 void (*flash_resume)(struct led_classdev *led_cdev); 87 88 struct work_struct set_brightness_work; 89 int delayed_set_value; 90 91#ifdef CONFIG_LEDS_TRIGGERS 92 /* Protects the trigger data below */ 93 struct rw_semaphore trigger_lock; 94 95 struct led_trigger *trigger; 96 struct list_head trig_list; 97 void *trigger_data; 98 /* true if activated - deactivate routine uses it to do cleanup */ 99 bool activated; 100#endif 101 102 /* Ensures consistent access to the LED Flash Class device */ 103 struct mutex led_access; 104}; 105 106extern int led_classdev_register(struct device *parent, 107 struct led_classdev *led_cdev); 108extern int devm_led_classdev_register(struct device *parent, 109 struct led_classdev *led_cdev); 110extern void led_classdev_unregister(struct led_classdev *led_cdev); 111extern void devm_led_classdev_unregister(struct device *parent, 112 struct led_classdev *led_cdev); 113extern void led_classdev_suspend(struct led_classdev *led_cdev); 114extern void led_classdev_resume(struct led_classdev *led_cdev); 115 116/** 117 * led_blink_set - set blinking with software fallback 118 * @led_cdev: the LED to start blinking 119 * @delay_on: the time it should be on (in ms) 120 * @delay_off: the time it should ble off (in ms) 121 * 122 * This function makes the LED blink, attempting to use the 123 * hardware acceleration if possible, but falling back to 124 * software blinking if there is no hardware blinking or if 125 * the LED refuses the passed values. 126 * 127 * Note that if software blinking is active, simply calling 128 * led_cdev->brightness_set() will not stop the blinking, 129 * use led_classdev_brightness_set() instead. 130 */ 131extern void led_blink_set(struct led_classdev *led_cdev, 132 unsigned long *delay_on, 133 unsigned long *delay_off); 134/** 135 * led_blink_set_oneshot - do a oneshot software blink 136 * @led_cdev: the LED to start blinking 137 * @delay_on: the time it should be on (in ms) 138 * @delay_off: the time it should ble off (in ms) 139 * @invert: blink off, then on, leaving the led on 140 * 141 * This function makes the LED blink one time for delay_on + 142 * delay_off time, ignoring the request if another one-shot 143 * blink is already in progress. 144 * 145 * If invert is set, led blinks for delay_off first, then for 146 * delay_on and leave the led on after the on-off cycle. 147 */ 148extern void led_blink_set_oneshot(struct led_classdev *led_cdev, 149 unsigned long *delay_on, 150 unsigned long *delay_off, 151 int invert); 152/** 153 * led_set_brightness - set LED brightness 154 * @led_cdev: the LED to set 155 * @brightness: the brightness to set it to 156 * 157 * Set an LED's brightness, and, if necessary, cancel the 158 * software blink timer that implements blinking when the 159 * hardware doesn't. 160 */ 161extern void led_set_brightness(struct led_classdev *led_cdev, 162 enum led_brightness brightness); 163/** 164 * led_update_brightness - update LED brightness 165 * @led_cdev: the LED to query 166 * 167 * Get an LED's current brightness and update led_cdev->brightness 168 * member with the obtained value. 169 * 170 * Returns: 0 on success or negative error value on failure 171 */ 172extern int led_update_brightness(struct led_classdev *led_cdev); 173 174/** 175 * led_sysfs_disable - disable LED sysfs interface 176 * @led_cdev: the LED to set 177 * 178 * Disable the led_cdev's sysfs interface. 179 */ 180extern void led_sysfs_disable(struct led_classdev *led_cdev); 181 182/** 183 * led_sysfs_enable - enable LED sysfs interface 184 * @led_cdev: the LED to set 185 * 186 * Enable the led_cdev's sysfs interface. 187 */ 188extern void led_sysfs_enable(struct led_classdev *led_cdev); 189 190/** 191 * led_sysfs_is_disabled - check if LED sysfs interface is disabled 192 * @led_cdev: the LED to query 193 * 194 * Returns: true if the led_cdev's sysfs interface is disabled. 195 */ 196static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev) 197{ 198 return led_cdev->flags & LED_SYSFS_DISABLE; 199} 200 201/* 202 * LED Triggers 203 */ 204/* Registration functions for simple triggers */ 205#define DEFINE_LED_TRIGGER(x) static struct led_trigger *x; 206#define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x; 207 208#ifdef CONFIG_LEDS_TRIGGERS 209 210#define TRIG_NAME_MAX 50 211 212struct led_trigger { 213 /* Trigger Properties */ 214 const char *name; 215 void (*activate)(struct led_classdev *led_cdev); 216 void (*deactivate)(struct led_classdev *led_cdev); 217 218 /* LEDs under control by this trigger (for simple triggers) */ 219 rwlock_t leddev_list_lock; 220 struct list_head led_cdevs; 221 222 /* Link to next registered trigger */ 223 struct list_head next_trig; 224}; 225 226ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, 227 const char *buf, size_t count); 228ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr, 229 char *buf); 230 231/* Registration functions for complex triggers */ 232extern int led_trigger_register(struct led_trigger *trigger); 233extern void led_trigger_unregister(struct led_trigger *trigger); 234 235extern void led_trigger_register_simple(const char *name, 236 struct led_trigger **trigger); 237extern void led_trigger_unregister_simple(struct led_trigger *trigger); 238extern void led_trigger_event(struct led_trigger *trigger, 239 enum led_brightness event); 240extern void led_trigger_blink(struct led_trigger *trigger, 241 unsigned long *delay_on, 242 unsigned long *delay_off); 243extern void led_trigger_blink_oneshot(struct led_trigger *trigger, 244 unsigned long *delay_on, 245 unsigned long *delay_off, 246 int invert); 247extern void led_trigger_set_default(struct led_classdev *led_cdev); 248extern void led_trigger_set(struct led_classdev *led_cdev, 249 struct led_trigger *trigger); 250extern void led_trigger_remove(struct led_classdev *led_cdev); 251 252static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 253{ 254 return led_cdev->trigger_data; 255} 256 257/** 258 * led_trigger_rename_static - rename a trigger 259 * @name: the new trigger name 260 * @trig: the LED trigger to rename 261 * 262 * Change a LED trigger name by copying the string passed in 263 * name into current trigger name, which MUST be large 264 * enough for the new string. 265 * 266 * Note that name must NOT point to the same string used 267 * during LED registration, as that could lead to races. 268 * 269 * This is meant to be used on triggers with statically 270 * allocated name. 271 */ 272extern void led_trigger_rename_static(const char *name, 273 struct led_trigger *trig); 274 275#else 276 277/* Trigger has no members */ 278struct led_trigger {}; 279 280/* Trigger inline empty functions */ 281static inline void led_trigger_register_simple(const char *name, 282 struct led_trigger **trigger) {} 283static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {} 284static inline void led_trigger_event(struct led_trigger *trigger, 285 enum led_brightness event) {} 286static inline void led_trigger_blink(struct led_trigger *trigger, 287 unsigned long *delay_on, 288 unsigned long *delay_off) {} 289static inline void led_trigger_blink_oneshot(struct led_trigger *trigger, 290 unsigned long *delay_on, 291 unsigned long *delay_off, 292 int invert) {} 293static inline void led_trigger_set_default(struct led_classdev *led_cdev) {} 294static inline void led_trigger_set(struct led_classdev *led_cdev, 295 struct led_trigger *trigger) {} 296static inline void led_trigger_remove(struct led_classdev *led_cdev) {} 297static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 298{ 299 return NULL; 300} 301 302#endif /* CONFIG_LEDS_TRIGGERS */ 303 304/* Trigger specific functions */ 305#ifdef CONFIG_LEDS_TRIGGER_IDE_DISK 306extern void ledtrig_ide_activity(void); 307#else 308static inline void ledtrig_ide_activity(void) {} 309#endif 310 311#if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE) 312extern void ledtrig_flash_ctrl(bool on); 313extern void ledtrig_torch_ctrl(bool on); 314#else 315static inline void ledtrig_flash_ctrl(bool on) {} 316static inline void ledtrig_torch_ctrl(bool on) {} 317#endif 318 319/* 320 * Generic LED platform data for describing LED names and default triggers. 321 */ 322struct led_info { 323 const char *name; 324 const char *default_trigger; 325 int flags; 326}; 327 328struct led_platform_data { 329 int num_leds; 330 struct led_info *leds; 331}; 332 333/* For the leds-gpio driver */ 334struct gpio_led { 335 const char *name; 336 const char *default_trigger; 337 unsigned gpio; 338 unsigned active_low : 1; 339 unsigned retain_state_suspended : 1; 340 unsigned default_state : 2; 341 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ 342 struct gpio_desc *gpiod; 343}; 344#define LEDS_GPIO_DEFSTATE_OFF 0 345#define LEDS_GPIO_DEFSTATE_ON 1 346#define LEDS_GPIO_DEFSTATE_KEEP 2 347 348struct gpio_led_platform_data { 349 int num_leds; 350 const struct gpio_led *leds; 351 352#define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */ 353#define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */ 354#define GPIO_LED_BLINK 2 /* Please, blink */ 355 int (*gpio_blink_set)(struct gpio_desc *desc, int state, 356 unsigned long *delay_on, 357 unsigned long *delay_off); 358}; 359 360struct platform_device *gpio_led_register_device( 361 int id, const struct gpio_led_platform_data *pdata); 362 363enum cpu_led_event { 364 CPU_LED_IDLE_START, /* CPU enters idle */ 365 CPU_LED_IDLE_END, /* CPU idle ends */ 366 CPU_LED_START, /* Machine starts, especially resume */ 367 CPU_LED_STOP, /* Machine stops, especially suspend */ 368 CPU_LED_HALTED, /* Machine shutdown */ 369}; 370#ifdef CONFIG_LEDS_TRIGGER_CPU 371extern void ledtrig_cpu(enum cpu_led_event evt); 372#else 373static inline void ledtrig_cpu(enum cpu_led_event evt) 374{ 375 return; 376} 377#endif 378 379#endif /* __LINUX_LEDS_H_INCLUDED */ 380