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