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/kernfs.h> 17 #include <linux/list.h> 18 #include <linux/mutex.h> 19 #include <linux/rwsem.h> 20 #include <linux/spinlock.h> 21 #include <linux/timer.h> 22 #include <linux/workqueue.h> 23 24 struct device; 25 struct led_pattern; 26 /* 27 * LED Core 28 */ 29 30 enum led_brightness { 31 LED_OFF = 0, 32 LED_ON = 1, 33 LED_HALF = 127, 34 LED_FULL = 255, 35 }; 36 37 struct led_classdev { 38 const char *name; 39 enum led_brightness brightness; 40 enum led_brightness max_brightness; 41 int flags; 42 43 /* Lower 16 bits reflect status */ 44 #define LED_SUSPENDED BIT(0) 45 #define LED_UNREGISTERING BIT(1) 46 /* Upper 16 bits reflect control information */ 47 #define LED_CORE_SUSPENDRESUME BIT(16) 48 #define LED_SYSFS_DISABLE BIT(17) 49 #define LED_DEV_CAP_FLASH BIT(18) 50 #define LED_HW_PLUGGABLE BIT(19) 51 #define LED_PANIC_INDICATOR BIT(20) 52 #define LED_BRIGHT_HW_CHANGED BIT(21) 53 #define LED_RETAIN_AT_SHUTDOWN BIT(22) 54 #define LED_INIT_DEFAULT_TRIGGER BIT(23) 55 56 /* set_brightness_work / blink_timer flags, atomic, private. */ 57 unsigned long work_flags; 58 59 #define LED_BLINK_SW 0 60 #define LED_BLINK_ONESHOT 1 61 #define LED_BLINK_ONESHOT_STOP 2 62 #define LED_BLINK_INVERT 3 63 #define LED_BLINK_BRIGHTNESS_CHANGE 4 64 #define LED_BLINK_DISABLE 5 65 66 /* Set LED brightness level 67 * Must not sleep. Use brightness_set_blocking for drivers 68 * that can sleep while setting brightness. 69 */ 70 void (*brightness_set)(struct led_classdev *led_cdev, 71 enum led_brightness brightness); 72 /* 73 * Set LED brightness level immediately - it can block the caller for 74 * the time required for accessing a LED device register. 75 */ 76 int (*brightness_set_blocking)(struct led_classdev *led_cdev, 77 enum led_brightness brightness); 78 /* Get LED brightness level */ 79 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev); 80 81 /* 82 * Activate hardware accelerated blink, delays are in milliseconds 83 * and if both are zero then a sensible default should be chosen. 84 * The call should adjust the timings in that case and if it can't 85 * match the values specified exactly. 86 * Deactivate blinking again when the brightness is set to LED_OFF 87 * via the brightness_set() callback. 88 */ 89 int (*blink_set)(struct led_classdev *led_cdev, 90 unsigned long *delay_on, 91 unsigned long *delay_off); 92 93 int (*pattern_set)(struct led_classdev *led_cdev, 94 struct led_pattern *pattern, u32 len, int repeat); 95 int (*pattern_clear)(struct led_classdev *led_cdev); 96 97 struct device *dev; 98 const struct attribute_group **groups; 99 100 struct list_head node; /* LED Device list */ 101 const char *default_trigger; /* Trigger to use */ 102 103 unsigned long blink_delay_on, blink_delay_off; 104 struct timer_list blink_timer; 105 int blink_brightness; 106 int new_blink_brightness; 107 void (*flash_resume)(struct led_classdev *led_cdev); 108 109 struct work_struct set_brightness_work; 110 int delayed_set_value; 111 112 #ifdef CONFIG_LEDS_TRIGGERS 113 /* Protects the trigger data below */ 114 struct rw_semaphore trigger_lock; 115 116 struct led_trigger *trigger; 117 struct list_head trig_list; 118 void *trigger_data; 119 /* true if activated - deactivate routine uses it to do cleanup */ 120 bool activated; 121 #endif 122 123 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED 124 int brightness_hw_changed; 125 struct kernfs_node *brightness_hw_changed_kn; 126 #endif 127 128 /* Ensures consistent access to the LED Flash Class device */ 129 struct mutex led_access; 130 }; 131 132 extern int of_led_classdev_register(struct device *parent, 133 struct device_node *np, 134 struct led_classdev *led_cdev); 135 #define led_classdev_register(parent, led_cdev) \ 136 of_led_classdev_register(parent, NULL, led_cdev) 137 extern int devm_of_led_classdev_register(struct device *parent, 138 struct device_node *np, 139 struct led_classdev *led_cdev); 140 #define devm_led_classdev_register(parent, led_cdev) \ 141 devm_of_led_classdev_register(parent, NULL, led_cdev) 142 extern void led_classdev_unregister(struct led_classdev *led_cdev); 143 extern void devm_led_classdev_unregister(struct device *parent, 144 struct led_classdev *led_cdev); 145 extern void led_classdev_suspend(struct led_classdev *led_cdev); 146 extern void led_classdev_resume(struct led_classdev *led_cdev); 147 148 /** 149 * led_blink_set - set blinking with software fallback 150 * @led_cdev: the LED to start blinking 151 * @delay_on: the time it should be on (in ms) 152 * @delay_off: the time it should ble off (in ms) 153 * 154 * This function makes the LED blink, attempting to use the 155 * hardware acceleration if possible, but falling back to 156 * software blinking if there is no hardware blinking or if 157 * the LED refuses the passed values. 158 * 159 * Note that if software blinking is active, simply calling 160 * led_cdev->brightness_set() will not stop the blinking, 161 * use led_classdev_brightness_set() instead. 162 */ 163 extern void led_blink_set(struct led_classdev *led_cdev, 164 unsigned long *delay_on, 165 unsigned long *delay_off); 166 /** 167 * led_blink_set_oneshot - do a oneshot software blink 168 * @led_cdev: the LED to start blinking 169 * @delay_on: the time it should be on (in ms) 170 * @delay_off: the time it should ble off (in ms) 171 * @invert: blink off, then on, leaving the led on 172 * 173 * This function makes the LED blink one time for delay_on + 174 * delay_off time, ignoring the request if another one-shot 175 * blink is already in progress. 176 * 177 * If invert is set, led blinks for delay_off first, then for 178 * delay_on and leave the led on after the on-off cycle. 179 */ 180 extern void led_blink_set_oneshot(struct led_classdev *led_cdev, 181 unsigned long *delay_on, 182 unsigned long *delay_off, 183 int invert); 184 /** 185 * led_set_brightness - set LED brightness 186 * @led_cdev: the LED to set 187 * @brightness: the brightness to set it to 188 * 189 * Set an LED's brightness, and, if necessary, cancel the 190 * software blink timer that implements blinking when the 191 * hardware doesn't. This function is guaranteed not to sleep. 192 */ 193 extern void led_set_brightness(struct led_classdev *led_cdev, 194 enum led_brightness brightness); 195 196 /** 197 * led_set_brightness_sync - set LED brightness synchronously 198 * @led_cdev: the LED to set 199 * @brightness: the brightness to set it to 200 * 201 * Set an LED's brightness immediately. This function will block 202 * the caller for the time required for accessing device registers, 203 * and it can sleep. 204 * 205 * Returns: 0 on success or negative error value on failure 206 */ 207 extern int led_set_brightness_sync(struct led_classdev *led_cdev, 208 enum led_brightness value); 209 210 /** 211 * led_update_brightness - update LED brightness 212 * @led_cdev: the LED to query 213 * 214 * Get an LED's current brightness and update led_cdev->brightness 215 * member with the obtained value. 216 * 217 * Returns: 0 on success or negative error value on failure 218 */ 219 extern int led_update_brightness(struct led_classdev *led_cdev); 220 221 /** 222 * led_get_default_pattern - return default pattern 223 * 224 * @led_cdev: the LED to get default pattern for 225 * @size: pointer for storing the number of elements in returned array, 226 * modified only if return != NULL 227 * 228 * Return: Allocated array of integers with default pattern from device tree 229 * or NULL. Caller is responsible for kfree(). 230 */ 231 extern u32 *led_get_default_pattern(struct led_classdev *led_cdev, 232 unsigned int *size); 233 234 /** 235 * led_sysfs_disable - disable LED sysfs interface 236 * @led_cdev: the LED to set 237 * 238 * Disable the led_cdev's sysfs interface. 239 */ 240 extern void led_sysfs_disable(struct led_classdev *led_cdev); 241 242 /** 243 * led_sysfs_enable - enable LED sysfs interface 244 * @led_cdev: the LED to set 245 * 246 * Enable the led_cdev's sysfs interface. 247 */ 248 extern void led_sysfs_enable(struct led_classdev *led_cdev); 249 250 /** 251 * led_sysfs_is_disabled - check if LED sysfs interface is disabled 252 * @led_cdev: the LED to query 253 * 254 * Returns: true if the led_cdev's sysfs interface is disabled. 255 */ 256 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev) 257 { 258 return led_cdev->flags & LED_SYSFS_DISABLE; 259 } 260 261 /* 262 * LED Triggers 263 */ 264 /* Registration functions for simple triggers */ 265 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x; 266 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x; 267 268 #ifdef CONFIG_LEDS_TRIGGERS 269 270 #define TRIG_NAME_MAX 50 271 272 struct led_trigger { 273 /* Trigger Properties */ 274 const char *name; 275 int (*activate)(struct led_classdev *led_cdev); 276 void (*deactivate)(struct led_classdev *led_cdev); 277 278 /* LEDs under control by this trigger (for simple triggers) */ 279 rwlock_t leddev_list_lock; 280 struct list_head led_cdevs; 281 282 /* Link to next registered trigger */ 283 struct list_head next_trig; 284 285 const struct attribute_group **groups; 286 }; 287 288 /* 289 * Currently the attributes in struct led_trigger::groups are added directly to 290 * the LED device. As this might change in the future, the following 291 * macros abstract getting the LED device and its trigger_data from the dev 292 * parameter passed to the attribute accessor functions. 293 */ 294 #define led_trigger_get_led(dev) ((struct led_classdev *)dev_get_drvdata((dev))) 295 #define led_trigger_get_drvdata(dev) (led_get_trigger_data(led_trigger_get_led(dev))) 296 297 ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, 298 const char *buf, size_t count); 299 ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr, 300 char *buf); 301 302 /* Registration functions for complex triggers */ 303 extern int led_trigger_register(struct led_trigger *trigger); 304 extern void led_trigger_unregister(struct led_trigger *trigger); 305 extern int devm_led_trigger_register(struct device *dev, 306 struct led_trigger *trigger); 307 308 extern void led_trigger_register_simple(const char *name, 309 struct led_trigger **trigger); 310 extern void led_trigger_unregister_simple(struct led_trigger *trigger); 311 extern void led_trigger_event(struct led_trigger *trigger, 312 enum led_brightness event); 313 extern void led_trigger_blink(struct led_trigger *trigger, 314 unsigned long *delay_on, 315 unsigned long *delay_off); 316 extern void led_trigger_blink_oneshot(struct led_trigger *trigger, 317 unsigned long *delay_on, 318 unsigned long *delay_off, 319 int invert); 320 extern void led_trigger_set_default(struct led_classdev *led_cdev); 321 extern int led_trigger_set(struct led_classdev *led_cdev, 322 struct led_trigger *trigger); 323 extern void led_trigger_remove(struct led_classdev *led_cdev); 324 325 static inline void led_set_trigger_data(struct led_classdev *led_cdev, 326 void *trigger_data) 327 { 328 led_cdev->trigger_data = trigger_data; 329 } 330 331 static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 332 { 333 return led_cdev->trigger_data; 334 } 335 336 /** 337 * led_trigger_rename_static - rename a trigger 338 * @name: the new trigger name 339 * @trig: the LED trigger to rename 340 * 341 * Change a LED trigger name by copying the string passed in 342 * name into current trigger name, which MUST be large 343 * enough for the new string. 344 * 345 * Note that name must NOT point to the same string used 346 * during LED registration, as that could lead to races. 347 * 348 * This is meant to be used on triggers with statically 349 * allocated name. 350 */ 351 extern void led_trigger_rename_static(const char *name, 352 struct led_trigger *trig); 353 354 #define module_led_trigger(__led_trigger) \ 355 module_driver(__led_trigger, led_trigger_register, \ 356 led_trigger_unregister) 357 358 #else 359 360 /* Trigger has no members */ 361 struct led_trigger {}; 362 363 /* Trigger inline empty functions */ 364 static inline void led_trigger_register_simple(const char *name, 365 struct led_trigger **trigger) {} 366 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {} 367 static inline void led_trigger_event(struct led_trigger *trigger, 368 enum led_brightness event) {} 369 static inline void led_trigger_blink(struct led_trigger *trigger, 370 unsigned long *delay_on, 371 unsigned long *delay_off) {} 372 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger, 373 unsigned long *delay_on, 374 unsigned long *delay_off, 375 int invert) {} 376 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {} 377 static inline int led_trigger_set(struct led_classdev *led_cdev, 378 struct led_trigger *trigger) 379 { 380 return 0; 381 } 382 383 static inline void led_trigger_remove(struct led_classdev *led_cdev) {} 384 static inline void led_set_trigger_data(struct led_classdev *led_cdev) {} 385 static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 386 { 387 return NULL; 388 } 389 390 #endif /* CONFIG_LEDS_TRIGGERS */ 391 392 /* Trigger specific functions */ 393 #ifdef CONFIG_LEDS_TRIGGER_DISK 394 extern void ledtrig_disk_activity(bool write); 395 #else 396 static inline void ledtrig_disk_activity(bool write) {} 397 #endif 398 399 #ifdef CONFIG_LEDS_TRIGGER_MTD 400 extern void ledtrig_mtd_activity(void); 401 #else 402 static inline void ledtrig_mtd_activity(void) {} 403 #endif 404 405 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE) 406 extern void ledtrig_flash_ctrl(bool on); 407 extern void ledtrig_torch_ctrl(bool on); 408 #else 409 static inline void ledtrig_flash_ctrl(bool on) {} 410 static inline void ledtrig_torch_ctrl(bool on) {} 411 #endif 412 413 /* 414 * Generic LED platform data for describing LED names and default triggers. 415 */ 416 struct led_info { 417 const char *name; 418 const char *default_trigger; 419 int flags; 420 }; 421 422 struct led_platform_data { 423 int num_leds; 424 struct led_info *leds; 425 }; 426 427 struct gpio_desc; 428 typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state, 429 unsigned long *delay_on, 430 unsigned long *delay_off); 431 432 /* For the leds-gpio driver */ 433 struct gpio_led { 434 const char *name; 435 const char *default_trigger; 436 unsigned gpio; 437 unsigned active_low : 1; 438 unsigned retain_state_suspended : 1; 439 unsigned panic_indicator : 1; 440 unsigned default_state : 2; 441 unsigned retain_state_shutdown : 1; 442 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ 443 struct gpio_desc *gpiod; 444 }; 445 #define LEDS_GPIO_DEFSTATE_OFF 0 446 #define LEDS_GPIO_DEFSTATE_ON 1 447 #define LEDS_GPIO_DEFSTATE_KEEP 2 448 449 struct gpio_led_platform_data { 450 int num_leds; 451 const struct gpio_led *leds; 452 453 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */ 454 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */ 455 #define GPIO_LED_BLINK 2 /* Please, blink */ 456 gpio_blink_set_t gpio_blink_set; 457 }; 458 459 #ifdef CONFIG_NEW_LEDS 460 struct platform_device *gpio_led_register_device( 461 int id, const struct gpio_led_platform_data *pdata); 462 #else 463 static inline struct platform_device *gpio_led_register_device( 464 int id, const struct gpio_led_platform_data *pdata) 465 { 466 return 0; 467 } 468 #endif 469 470 enum cpu_led_event { 471 CPU_LED_IDLE_START, /* CPU enters idle */ 472 CPU_LED_IDLE_END, /* CPU idle ends */ 473 CPU_LED_START, /* Machine starts, especially resume */ 474 CPU_LED_STOP, /* Machine stops, especially suspend */ 475 CPU_LED_HALTED, /* Machine shutdown */ 476 }; 477 #ifdef CONFIG_LEDS_TRIGGER_CPU 478 extern void ledtrig_cpu(enum cpu_led_event evt); 479 #else 480 static inline void ledtrig_cpu(enum cpu_led_event evt) 481 { 482 return; 483 } 484 #endif 485 486 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED 487 extern void led_classdev_notify_brightness_hw_changed( 488 struct led_classdev *led_cdev, enum led_brightness brightness); 489 #else 490 static inline void led_classdev_notify_brightness_hw_changed( 491 struct led_classdev *led_cdev, enum led_brightness brightness) { } 492 #endif 493 494 /** 495 * struct led_pattern - pattern interval settings 496 * @delta_t: pattern interval delay, in milliseconds 497 * @brightness: pattern interval brightness 498 */ 499 struct led_pattern { 500 u32 delta_t; 501 int brightness; 502 }; 503 504 enum led_audio { 505 LED_AUDIO_MUTE, /* master mute LED */ 506 LED_AUDIO_MICMUTE, /* mic mute LED */ 507 NUM_AUDIO_LEDS 508 }; 509 510 #if IS_ENABLED(CONFIG_LEDS_TRIGGER_AUDIO) 511 enum led_brightness ledtrig_audio_get(enum led_audio type); 512 void ledtrig_audio_set(enum led_audio type, enum led_brightness state); 513 #else 514 static inline enum led_brightness ledtrig_audio_get(enum led_audio type) 515 { 516 return LED_OFF; 517 } 518 static inline void ledtrig_audio_set(enum led_audio type, 519 enum led_brightness state) 520 { 521 } 522 #endif 523 524 #endif /* __LINUX_LEDS_H_INCLUDED */ 525