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