1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Driver model for leds and led triggers 4 * 5 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu> 6 * Copyright (C) 2005 Richard Purdie <rpurdie@openedhand.com> 7 */ 8 #ifndef __LINUX_LEDS_H_INCLUDED 9 #define __LINUX_LEDS_H_INCLUDED 10 11 #include <dt-bindings/leds/common.h> 12 #include <linux/device.h> 13 #include <linux/kernfs.h> 14 #include <linux/list.h> 15 #include <linux/mutex.h> 16 #include <linux/rwsem.h> 17 #include <linux/spinlock.h> 18 #include <linux/timer.h> 19 #include <linux/workqueue.h> 20 21 struct device; 22 struct led_pattern; 23 struct device_node; 24 /* 25 * LED Core 26 */ 27 28 /* This is obsolete/useless. We now support variable maximum brightness. */ 29 enum led_brightness { 30 LED_OFF = 0, 31 LED_ON = 1, 32 LED_HALF = 127, 33 LED_FULL = 255, 34 }; 35 36 enum led_default_state { 37 LEDS_DEFSTATE_OFF = 0, 38 LEDS_DEFSTATE_ON = 1, 39 LEDS_DEFSTATE_KEEP = 2, 40 }; 41 42 struct led_init_data { 43 /* device fwnode handle */ 44 struct fwnode_handle *fwnode; 45 /* 46 * default <color:function> tuple, for backward compatibility 47 * with in-driver hard-coded LED names used as a fallback when 48 * DT "label" property is absent; it should be set to NULL 49 * in new LED class drivers. 50 */ 51 const char *default_label; 52 /* 53 * string to be used for devicename section of LED class device 54 * either for label based LED name composition path or for fwnode 55 * based when devname_mandatory is true 56 */ 57 const char *devicename; 58 /* 59 * indicates if LED name should always comprise devicename section; 60 * only LEDs exposed by drivers of hot-pluggable devices should 61 * set it to true 62 */ 63 bool devname_mandatory; 64 }; 65 66 struct led_hw_trigger_type { 67 int dummy; 68 }; 69 70 struct led_classdev { 71 const char *name; 72 unsigned int brightness; 73 unsigned int max_brightness; 74 int flags; 75 76 /* Lower 16 bits reflect status */ 77 #define LED_SUSPENDED BIT(0) 78 #define LED_UNREGISTERING BIT(1) 79 /* Upper 16 bits reflect control information */ 80 #define LED_CORE_SUSPENDRESUME BIT(16) 81 #define LED_SYSFS_DISABLE BIT(17) 82 #define LED_DEV_CAP_FLASH BIT(18) 83 #define LED_HW_PLUGGABLE BIT(19) 84 #define LED_PANIC_INDICATOR BIT(20) 85 #define LED_BRIGHT_HW_CHANGED BIT(21) 86 #define LED_RETAIN_AT_SHUTDOWN BIT(22) 87 #define LED_INIT_DEFAULT_TRIGGER BIT(23) 88 89 /* set_brightness_work / blink_timer flags, atomic, private. */ 90 unsigned long work_flags; 91 92 #define LED_BLINK_SW 0 93 #define LED_BLINK_ONESHOT 1 94 #define LED_BLINK_ONESHOT_STOP 2 95 #define LED_BLINK_INVERT 3 96 #define LED_BLINK_BRIGHTNESS_CHANGE 4 97 #define LED_BLINK_DISABLE 5 98 99 /* Set LED brightness level 100 * Must not sleep. Use brightness_set_blocking for drivers 101 * that can sleep while setting brightness. 102 */ 103 void (*brightness_set)(struct led_classdev *led_cdev, 104 enum led_brightness brightness); 105 /* 106 * Set LED brightness level immediately - it can block the caller for 107 * the time required for accessing a LED device register. 108 */ 109 int (*brightness_set_blocking)(struct led_classdev *led_cdev, 110 enum led_brightness brightness); 111 /* Get LED brightness level */ 112 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev); 113 114 /* 115 * Activate hardware accelerated blink, delays are in milliseconds 116 * and if both are zero then a sensible default should be chosen. 117 * The call should adjust the timings in that case and if it can't 118 * match the values specified exactly. 119 * Deactivate blinking again when the brightness is set to LED_OFF 120 * via the brightness_set() callback. 121 */ 122 int (*blink_set)(struct led_classdev *led_cdev, 123 unsigned long *delay_on, 124 unsigned long *delay_off); 125 126 int (*pattern_set)(struct led_classdev *led_cdev, 127 struct led_pattern *pattern, u32 len, int repeat); 128 int (*pattern_clear)(struct led_classdev *led_cdev); 129 130 struct device *dev; 131 const struct attribute_group **groups; 132 133 struct list_head node; /* LED Device list */ 134 const char *default_trigger; /* Trigger to use */ 135 136 unsigned long blink_delay_on, blink_delay_off; 137 struct timer_list blink_timer; 138 int blink_brightness; 139 int new_blink_brightness; 140 void (*flash_resume)(struct led_classdev *led_cdev); 141 142 struct work_struct set_brightness_work; 143 int delayed_set_value; 144 145 #ifdef CONFIG_LEDS_TRIGGERS 146 /* Protects the trigger data below */ 147 struct rw_semaphore trigger_lock; 148 149 struct led_trigger *trigger; 150 struct list_head trig_list; 151 void *trigger_data; 152 /* true if activated - deactivate routine uses it to do cleanup */ 153 bool activated; 154 155 /* LEDs that have private triggers have this set */ 156 struct led_hw_trigger_type *trigger_type; 157 #endif 158 159 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED 160 int brightness_hw_changed; 161 struct kernfs_node *brightness_hw_changed_kn; 162 #endif 163 164 /* Ensures consistent access to the LED Flash Class device */ 165 struct mutex led_access; 166 }; 167 168 /** 169 * led_classdev_register_ext - register a new object of LED class with 170 * init data 171 * @parent: LED controller device this LED is driven by 172 * @led_cdev: the led_classdev structure for this device 173 * @init_data: the LED class device initialization data 174 * 175 * Register a new object of LED class, with name derived from init_data. 176 * 177 * Returns: 0 on success or negative error value on failure 178 */ 179 int led_classdev_register_ext(struct device *parent, 180 struct led_classdev *led_cdev, 181 struct led_init_data *init_data); 182 183 /** 184 * led_classdev_register - register a new object of LED class 185 * @parent: LED controller device this LED is driven by 186 * @led_cdev: the led_classdev structure for this device 187 * 188 * Register a new object of LED class, with name derived from the name property 189 * of passed led_cdev argument. 190 * 191 * Returns: 0 on success or negative error value on failure 192 */ led_classdev_register(struct device * parent,struct led_classdev * led_cdev)193 static inline int led_classdev_register(struct device *parent, 194 struct led_classdev *led_cdev) 195 { 196 return led_classdev_register_ext(parent, led_cdev, NULL); 197 } 198 199 int devm_led_classdev_register_ext(struct device *parent, 200 struct led_classdev *led_cdev, 201 struct led_init_data *init_data); 202 devm_led_classdev_register(struct device * parent,struct led_classdev * led_cdev)203 static inline int devm_led_classdev_register(struct device *parent, 204 struct led_classdev *led_cdev) 205 { 206 return devm_led_classdev_register_ext(parent, led_cdev, NULL); 207 } 208 void led_classdev_unregister(struct led_classdev *led_cdev); 209 void devm_led_classdev_unregister(struct device *parent, 210 struct led_classdev *led_cdev); 211 void led_classdev_suspend(struct led_classdev *led_cdev); 212 void led_classdev_resume(struct led_classdev *led_cdev); 213 214 extern struct led_classdev *of_led_get(struct device_node *np, int index); 215 extern void led_put(struct led_classdev *led_cdev); 216 struct led_classdev *__must_check devm_of_led_get(struct device *dev, 217 int index); 218 219 /** 220 * led_blink_set - set blinking with software fallback 221 * @led_cdev: the LED to start blinking 222 * @delay_on: the time it should be on (in ms) 223 * @delay_off: the time it should ble off (in ms) 224 * 225 * This function makes the LED blink, attempting to use the 226 * hardware acceleration if possible, but falling back to 227 * software blinking if there is no hardware blinking or if 228 * the LED refuses the passed values. 229 * 230 * Note that if software blinking is active, simply calling 231 * led_cdev->brightness_set() will not stop the blinking, 232 * use led_classdev_brightness_set() instead. 233 */ 234 void led_blink_set(struct led_classdev *led_cdev, unsigned long *delay_on, 235 unsigned long *delay_off); 236 /** 237 * led_blink_set_oneshot - do a oneshot software blink 238 * @led_cdev: the LED to start blinking 239 * @delay_on: the time it should be on (in ms) 240 * @delay_off: the time it should ble off (in ms) 241 * @invert: blink off, then on, leaving the led on 242 * 243 * This function makes the LED blink one time for delay_on + 244 * delay_off time, ignoring the request if another one-shot 245 * blink is already in progress. 246 * 247 * If invert is set, led blinks for delay_off first, then for 248 * delay_on and leave the led on after the on-off cycle. 249 */ 250 void led_blink_set_oneshot(struct led_classdev *led_cdev, 251 unsigned long *delay_on, unsigned long *delay_off, 252 int invert); 253 /** 254 * led_set_brightness - set LED brightness 255 * @led_cdev: the LED to set 256 * @brightness: the brightness to set it to 257 * 258 * Set an LED's brightness, and, if necessary, cancel the 259 * software blink timer that implements blinking when the 260 * hardware doesn't. This function is guaranteed not to sleep. 261 */ 262 void led_set_brightness(struct led_classdev *led_cdev, unsigned int brightness); 263 264 /** 265 * led_set_brightness_sync - set LED brightness synchronously 266 * @led_cdev: the LED to set 267 * @value: the brightness to set it to 268 * 269 * Set an LED's brightness immediately. This function will block 270 * the caller for the time required for accessing device registers, 271 * and it can sleep. 272 * 273 * Returns: 0 on success or negative error value on failure 274 */ 275 int led_set_brightness_sync(struct led_classdev *led_cdev, unsigned int value); 276 277 /** 278 * led_update_brightness - update LED brightness 279 * @led_cdev: the LED to query 280 * 281 * Get an LED's current brightness and update led_cdev->brightness 282 * member with the obtained value. 283 * 284 * Returns: 0 on success or negative error value on failure 285 */ 286 int led_update_brightness(struct led_classdev *led_cdev); 287 288 /** 289 * led_get_default_pattern - return default pattern 290 * 291 * @led_cdev: the LED to get default pattern for 292 * @size: pointer for storing the number of elements in returned array, 293 * modified only if return != NULL 294 * 295 * Return: Allocated array of integers with default pattern from device tree 296 * or NULL. Caller is responsible for kfree(). 297 */ 298 u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size); 299 300 /** 301 * led_sysfs_disable - disable LED sysfs interface 302 * @led_cdev: the LED to set 303 * 304 * Disable the led_cdev's sysfs interface. 305 */ 306 void led_sysfs_disable(struct led_classdev *led_cdev); 307 308 /** 309 * led_sysfs_enable - enable LED sysfs interface 310 * @led_cdev: the LED to set 311 * 312 * Enable the led_cdev's sysfs interface. 313 */ 314 void led_sysfs_enable(struct led_classdev *led_cdev); 315 316 /** 317 * led_compose_name - compose LED class device name 318 * @dev: LED controller device object 319 * @init_data: the LED class device initialization data 320 * @led_classdev_name: composed LED class device name 321 * 322 * Create LED class device name basing on the provided init_data argument. 323 * The name can have <devicename:color:function> or <color:function>. 324 * form, depending on the init_data configuration. 325 * 326 * Returns: 0 on success or negative error value on failure 327 */ 328 int led_compose_name(struct device *dev, struct led_init_data *init_data, 329 char *led_classdev_name); 330 331 /** 332 * led_sysfs_is_disabled - check if LED sysfs interface is disabled 333 * @led_cdev: the LED to query 334 * 335 * Returns: true if the led_cdev's sysfs interface is disabled. 336 */ led_sysfs_is_disabled(struct led_classdev * led_cdev)337 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev) 338 { 339 return led_cdev->flags & LED_SYSFS_DISABLE; 340 } 341 342 /* 343 * LED Triggers 344 */ 345 /* Registration functions for simple triggers */ 346 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x; 347 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x; 348 349 #ifdef CONFIG_LEDS_TRIGGERS 350 351 #define TRIG_NAME_MAX 50 352 353 struct led_trigger { 354 /* Trigger Properties */ 355 const char *name; 356 int (*activate)(struct led_classdev *led_cdev); 357 void (*deactivate)(struct led_classdev *led_cdev); 358 359 /* LED-private triggers have this set */ 360 struct led_hw_trigger_type *trigger_type; 361 362 /* LEDs under control by this trigger (for simple triggers) */ 363 spinlock_t leddev_list_lock; 364 struct list_head led_cdevs; 365 366 /* Link to next registered trigger */ 367 struct list_head next_trig; 368 369 const struct attribute_group **groups; 370 }; 371 372 /* 373 * Currently the attributes in struct led_trigger::groups are added directly to 374 * the LED device. As this might change in the future, the following 375 * macros abstract getting the LED device and its trigger_data from the dev 376 * parameter passed to the attribute accessor functions. 377 */ 378 #define led_trigger_get_led(dev) ((struct led_classdev *)dev_get_drvdata((dev))) 379 #define led_trigger_get_drvdata(dev) (led_get_trigger_data(led_trigger_get_led(dev))) 380 381 /* Registration functions for complex triggers */ 382 int led_trigger_register(struct led_trigger *trigger); 383 void led_trigger_unregister(struct led_trigger *trigger); 384 int devm_led_trigger_register(struct device *dev, 385 struct led_trigger *trigger); 386 387 void led_trigger_register_simple(const char *name, 388 struct led_trigger **trigger); 389 void led_trigger_unregister_simple(struct led_trigger *trigger); 390 void led_trigger_event(struct led_trigger *trigger, enum led_brightness event); 391 void led_trigger_blink(struct led_trigger *trigger, unsigned long *delay_on, 392 unsigned long *delay_off); 393 void led_trigger_blink_oneshot(struct led_trigger *trigger, 394 unsigned long *delay_on, 395 unsigned long *delay_off, 396 int invert); 397 void led_trigger_set_default(struct led_classdev *led_cdev); 398 int led_trigger_set(struct led_classdev *led_cdev, struct led_trigger *trigger); 399 void led_trigger_remove(struct led_classdev *led_cdev); 400 led_set_trigger_data(struct led_classdev * led_cdev,void * trigger_data)401 static inline void led_set_trigger_data(struct led_classdev *led_cdev, 402 void *trigger_data) 403 { 404 led_cdev->trigger_data = trigger_data; 405 } 406 led_get_trigger_data(struct led_classdev * led_cdev)407 static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 408 { 409 return led_cdev->trigger_data; 410 } 411 412 /** 413 * led_trigger_rename_static - rename a trigger 414 * @name: the new trigger name 415 * @trig: the LED trigger to rename 416 * 417 * Change a LED trigger name by copying the string passed in 418 * name into current trigger name, which MUST be large 419 * enough for the new string. 420 * 421 * Note that name must NOT point to the same string used 422 * during LED registration, as that could lead to races. 423 * 424 * This is meant to be used on triggers with statically 425 * allocated name. 426 */ 427 void led_trigger_rename_static(const char *name, struct led_trigger *trig); 428 429 #define module_led_trigger(__led_trigger) \ 430 module_driver(__led_trigger, led_trigger_register, \ 431 led_trigger_unregister) 432 433 #else 434 435 /* Trigger has no members */ 436 struct led_trigger {}; 437 438 /* Trigger inline empty functions */ led_trigger_register_simple(const char * name,struct led_trigger ** trigger)439 static inline void led_trigger_register_simple(const char *name, 440 struct led_trigger **trigger) {} led_trigger_unregister_simple(struct led_trigger * trigger)441 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {} led_trigger_event(struct led_trigger * trigger,enum led_brightness event)442 static inline void led_trigger_event(struct led_trigger *trigger, 443 enum led_brightness event) {} led_trigger_blink(struct led_trigger * trigger,unsigned long * delay_on,unsigned long * delay_off)444 static inline void led_trigger_blink(struct led_trigger *trigger, 445 unsigned long *delay_on, 446 unsigned long *delay_off) {} led_trigger_blink_oneshot(struct led_trigger * trigger,unsigned long * delay_on,unsigned long * delay_off,int invert)447 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger, 448 unsigned long *delay_on, 449 unsigned long *delay_off, 450 int invert) {} led_trigger_set_default(struct led_classdev * led_cdev)451 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {} led_trigger_set(struct led_classdev * led_cdev,struct led_trigger * trigger)452 static inline int led_trigger_set(struct led_classdev *led_cdev, 453 struct led_trigger *trigger) 454 { 455 return 0; 456 } 457 led_trigger_remove(struct led_classdev * led_cdev)458 static inline void led_trigger_remove(struct led_classdev *led_cdev) {} led_set_trigger_data(struct led_classdev * led_cdev)459 static inline void led_set_trigger_data(struct led_classdev *led_cdev) {} led_get_trigger_data(struct led_classdev * led_cdev)460 static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 461 { 462 return NULL; 463 } 464 465 #endif /* CONFIG_LEDS_TRIGGERS */ 466 467 /* Trigger specific functions */ 468 #ifdef CONFIG_LEDS_TRIGGER_DISK 469 void ledtrig_disk_activity(bool write); 470 #else ledtrig_disk_activity(bool write)471 static inline void ledtrig_disk_activity(bool write) {} 472 #endif 473 474 #ifdef CONFIG_LEDS_TRIGGER_MTD 475 void ledtrig_mtd_activity(void); 476 #else ledtrig_mtd_activity(void)477 static inline void ledtrig_mtd_activity(void) {} 478 #endif 479 480 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE) 481 void ledtrig_flash_ctrl(bool on); 482 void ledtrig_torch_ctrl(bool on); 483 #else ledtrig_flash_ctrl(bool on)484 static inline void ledtrig_flash_ctrl(bool on) {} ledtrig_torch_ctrl(bool on)485 static inline void ledtrig_torch_ctrl(bool on) {} 486 #endif 487 488 /* 489 * Generic LED platform data for describing LED names and default triggers. 490 */ 491 struct led_info { 492 const char *name; 493 const char *default_trigger; 494 int flags; 495 }; 496 497 struct led_platform_data { 498 int num_leds; 499 struct led_info *leds; 500 }; 501 502 struct led_properties { 503 u32 color; 504 bool color_present; 505 const char *function; 506 u32 func_enum; 507 bool func_enum_present; 508 const char *label; 509 }; 510 511 struct gpio_desc; 512 typedef int (*gpio_blink_set_t)(struct gpio_desc *desc, int state, 513 unsigned long *delay_on, 514 unsigned long *delay_off); 515 516 /* For the leds-gpio driver */ 517 struct gpio_led { 518 const char *name; 519 const char *default_trigger; 520 unsigned gpio; 521 unsigned active_low : 1; 522 unsigned retain_state_suspended : 1; 523 unsigned panic_indicator : 1; 524 unsigned default_state : 2; 525 unsigned retain_state_shutdown : 1; 526 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ 527 struct gpio_desc *gpiod; 528 }; 529 #define LEDS_GPIO_DEFSTATE_OFF LEDS_DEFSTATE_OFF 530 #define LEDS_GPIO_DEFSTATE_ON LEDS_DEFSTATE_ON 531 #define LEDS_GPIO_DEFSTATE_KEEP LEDS_DEFSTATE_KEEP 532 533 struct gpio_led_platform_data { 534 int num_leds; 535 const struct gpio_led *leds; 536 537 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */ 538 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */ 539 #define GPIO_LED_BLINK 2 /* Please, blink */ 540 gpio_blink_set_t gpio_blink_set; 541 }; 542 543 #ifdef CONFIG_NEW_LEDS 544 struct platform_device *gpio_led_register_device( 545 int id, const struct gpio_led_platform_data *pdata); 546 #else gpio_led_register_device(int id,const struct gpio_led_platform_data * pdata)547 static inline struct platform_device *gpio_led_register_device( 548 int id, const struct gpio_led_platform_data *pdata) 549 { 550 return 0; 551 } 552 #endif 553 554 enum cpu_led_event { 555 CPU_LED_IDLE_START, /* CPU enters idle */ 556 CPU_LED_IDLE_END, /* CPU idle ends */ 557 CPU_LED_START, /* Machine starts, especially resume */ 558 CPU_LED_STOP, /* Machine stops, especially suspend */ 559 CPU_LED_HALTED, /* Machine shutdown */ 560 }; 561 #ifdef CONFIG_LEDS_TRIGGER_CPU 562 void ledtrig_cpu(enum cpu_led_event evt); 563 #else ledtrig_cpu(enum cpu_led_event evt)564 static inline void ledtrig_cpu(enum cpu_led_event evt) 565 { 566 return; 567 } 568 #endif 569 570 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED 571 void led_classdev_notify_brightness_hw_changed( 572 struct led_classdev *led_cdev, unsigned int brightness); 573 #else led_classdev_notify_brightness_hw_changed(struct led_classdev * led_cdev,enum led_brightness brightness)574 static inline void led_classdev_notify_brightness_hw_changed( 575 struct led_classdev *led_cdev, enum led_brightness brightness) { } 576 #endif 577 578 /** 579 * struct led_pattern - pattern interval settings 580 * @delta_t: pattern interval delay, in milliseconds 581 * @brightness: pattern interval brightness 582 */ 583 struct led_pattern { 584 u32 delta_t; 585 int brightness; 586 }; 587 588 enum led_audio { 589 LED_AUDIO_MUTE, /* master mute LED */ 590 LED_AUDIO_MICMUTE, /* mic mute LED */ 591 NUM_AUDIO_LEDS 592 }; 593 594 #if IS_ENABLED(CONFIG_LEDS_TRIGGER_AUDIO) 595 enum led_brightness ledtrig_audio_get(enum led_audio type); 596 void ledtrig_audio_set(enum led_audio type, enum led_brightness state); 597 #else ledtrig_audio_get(enum led_audio type)598 static inline enum led_brightness ledtrig_audio_get(enum led_audio type) 599 { 600 return LED_OFF; 601 } ledtrig_audio_set(enum led_audio type,enum led_brightness state)602 static inline void ledtrig_audio_set(enum led_audio type, 603 enum led_brightness state) 604 { 605 } 606 #endif 607 608 #endif /* __LINUX_LEDS_H_INCLUDED */ 609