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_BLINK_SW (1 << 17) 46 #define LED_BLINK_ONESHOT (1 << 18) 47 #define LED_BLINK_ONESHOT_STOP (1 << 19) 48 #define LED_BLINK_INVERT (1 << 20) 49 #define LED_BLINK_BRIGHTNESS_CHANGE (1 << 21) 50 #define LED_BLINK_DISABLE (1 << 22) 51 #define LED_SYSFS_DISABLE (1 << 23) 52 #define LED_DEV_CAP_FLASH (1 << 24) 53 #define LED_HW_PLUGGABLE (1 << 25) 54 #define LED_PANIC_INDICATOR (1 << 26) 55 56 /* Set LED brightness level 57 * Must not sleep. Use brightness_set_blocking for drivers 58 * that can sleep while setting brightness. 59 */ 60 void (*brightness_set)(struct led_classdev *led_cdev, 61 enum led_brightness brightness); 62 /* 63 * Set LED brightness level immediately - it can block the caller for 64 * the time required for accessing a LED device register. 65 */ 66 int (*brightness_set_blocking)(struct led_classdev *led_cdev, 67 enum led_brightness brightness); 68 /* Get LED brightness level */ 69 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev); 70 71 /* 72 * Activate hardware accelerated blink, delays are in milliseconds 73 * and if both are zero then a sensible default should be chosen. 74 * The call should adjust the timings in that case and if it can't 75 * match the values specified exactly. 76 * Deactivate blinking again when the brightness is set to LED_OFF 77 * via the brightness_set() callback. 78 */ 79 int (*blink_set)(struct led_classdev *led_cdev, 80 unsigned long *delay_on, 81 unsigned long *delay_off); 82 83 struct device *dev; 84 const struct attribute_group **groups; 85 86 struct list_head node; /* LED Device list */ 87 const char *default_trigger; /* Trigger to use */ 88 89 unsigned long blink_delay_on, blink_delay_off; 90 struct timer_list blink_timer; 91 int blink_brightness; 92 void (*flash_resume)(struct led_classdev *led_cdev); 93 94 struct work_struct set_brightness_work; 95 int delayed_set_value; 96 97 #ifdef CONFIG_LEDS_TRIGGERS 98 /* Protects the trigger data below */ 99 struct rw_semaphore trigger_lock; 100 101 struct led_trigger *trigger; 102 struct list_head trig_list; 103 void *trigger_data; 104 /* true if activated - deactivate routine uses it to do cleanup */ 105 bool activated; 106 #endif 107 108 /* Ensures consistent access to the LED Flash Class device */ 109 struct mutex led_access; 110 }; 111 112 extern int led_classdev_register(struct device *parent, 113 struct led_classdev *led_cdev); 114 extern int devm_led_classdev_register(struct device *parent, 115 struct led_classdev *led_cdev); 116 extern void led_classdev_unregister(struct led_classdev *led_cdev); 117 extern void devm_led_classdev_unregister(struct device *parent, 118 struct led_classdev *led_cdev); 119 extern void led_classdev_suspend(struct led_classdev *led_cdev); 120 extern void led_classdev_resume(struct led_classdev *led_cdev); 121 122 /** 123 * led_blink_set - set blinking with software fallback 124 * @led_cdev: the LED to start blinking 125 * @delay_on: the time it should be on (in ms) 126 * @delay_off: the time it should ble off (in ms) 127 * 128 * This function makes the LED blink, attempting to use the 129 * hardware acceleration if possible, but falling back to 130 * software blinking if there is no hardware blinking or if 131 * the LED refuses the passed values. 132 * 133 * Note that if software blinking is active, simply calling 134 * led_cdev->brightness_set() will not stop the blinking, 135 * use led_classdev_brightness_set() instead. 136 */ 137 extern void led_blink_set(struct led_classdev *led_cdev, 138 unsigned long *delay_on, 139 unsigned long *delay_off); 140 /** 141 * led_blink_set_oneshot - do a oneshot software blink 142 * @led_cdev: the LED to start blinking 143 * @delay_on: the time it should be on (in ms) 144 * @delay_off: the time it should ble off (in ms) 145 * @invert: blink off, then on, leaving the led on 146 * 147 * This function makes the LED blink one time for delay_on + 148 * delay_off time, ignoring the request if another one-shot 149 * blink is already in progress. 150 * 151 * If invert is set, led blinks for delay_off first, then for 152 * delay_on and leave the led on after the on-off cycle. 153 */ 154 extern void led_blink_set_oneshot(struct led_classdev *led_cdev, 155 unsigned long *delay_on, 156 unsigned long *delay_off, 157 int invert); 158 /** 159 * led_set_brightness - set LED brightness 160 * @led_cdev: the LED to set 161 * @brightness: the brightness to set it to 162 * 163 * Set an LED's brightness, and, if necessary, cancel the 164 * software blink timer that implements blinking when the 165 * hardware doesn't. This function is guaranteed not to sleep. 166 */ 167 extern void led_set_brightness(struct led_classdev *led_cdev, 168 enum led_brightness brightness); 169 170 /** 171 * led_set_brightness_sync - set LED brightness synchronously 172 * @led_cdev: the LED to set 173 * @brightness: the brightness to set it to 174 * 175 * Set an LED's brightness immediately. This function will block 176 * the caller for the time required for accessing device registers, 177 * and it can sleep. 178 * 179 * Returns: 0 on success or negative error value on failure 180 */ 181 extern int led_set_brightness_sync(struct led_classdev *led_cdev, 182 enum led_brightness value); 183 184 /** 185 * led_update_brightness - update LED brightness 186 * @led_cdev: the LED to query 187 * 188 * Get an LED's current brightness and update led_cdev->brightness 189 * member with the obtained value. 190 * 191 * Returns: 0 on success or negative error value on failure 192 */ 193 extern int led_update_brightness(struct led_classdev *led_cdev); 194 195 /** 196 * led_sysfs_disable - disable LED sysfs interface 197 * @led_cdev: the LED to set 198 * 199 * Disable the led_cdev's sysfs interface. 200 */ 201 extern void led_sysfs_disable(struct led_classdev *led_cdev); 202 203 /** 204 * led_sysfs_enable - enable LED sysfs interface 205 * @led_cdev: the LED to set 206 * 207 * Enable the led_cdev's sysfs interface. 208 */ 209 extern void led_sysfs_enable(struct led_classdev *led_cdev); 210 211 /** 212 * led_sysfs_is_disabled - check if LED sysfs interface is disabled 213 * @led_cdev: the LED to query 214 * 215 * Returns: true if the led_cdev's sysfs interface is disabled. 216 */ 217 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev) 218 { 219 return led_cdev->flags & LED_SYSFS_DISABLE; 220 } 221 222 /* 223 * LED Triggers 224 */ 225 /* Registration functions for simple triggers */ 226 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x; 227 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x; 228 229 #ifdef CONFIG_LEDS_TRIGGERS 230 231 #define TRIG_NAME_MAX 50 232 233 struct led_trigger { 234 /* Trigger Properties */ 235 const char *name; 236 void (*activate)(struct led_classdev *led_cdev); 237 void (*deactivate)(struct led_classdev *led_cdev); 238 239 /* LEDs under control by this trigger (for simple triggers) */ 240 rwlock_t leddev_list_lock; 241 struct list_head led_cdevs; 242 243 /* Link to next registered trigger */ 244 struct list_head next_trig; 245 }; 246 247 ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, 248 const char *buf, size_t count); 249 ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr, 250 char *buf); 251 252 /* Registration functions for complex triggers */ 253 extern int led_trigger_register(struct led_trigger *trigger); 254 extern void led_trigger_unregister(struct led_trigger *trigger); 255 extern int devm_led_trigger_register(struct device *dev, 256 struct led_trigger *trigger); 257 258 extern void led_trigger_register_simple(const char *name, 259 struct led_trigger **trigger); 260 extern void led_trigger_unregister_simple(struct led_trigger *trigger); 261 extern void led_trigger_event(struct led_trigger *trigger, 262 enum led_brightness event); 263 extern void led_trigger_blink(struct led_trigger *trigger, 264 unsigned long *delay_on, 265 unsigned long *delay_off); 266 extern void led_trigger_blink_oneshot(struct led_trigger *trigger, 267 unsigned long *delay_on, 268 unsigned long *delay_off, 269 int invert); 270 extern void led_trigger_set_default(struct led_classdev *led_cdev); 271 extern void led_trigger_set(struct led_classdev *led_cdev, 272 struct led_trigger *trigger); 273 extern void led_trigger_remove(struct led_classdev *led_cdev); 274 275 static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 276 { 277 return led_cdev->trigger_data; 278 } 279 280 /** 281 * led_trigger_rename_static - rename a trigger 282 * @name: the new trigger name 283 * @trig: the LED trigger to rename 284 * 285 * Change a LED trigger name by copying the string passed in 286 * name into current trigger name, which MUST be large 287 * enough for the new string. 288 * 289 * Note that name must NOT point to the same string used 290 * during LED registration, as that could lead to races. 291 * 292 * This is meant to be used on triggers with statically 293 * allocated name. 294 */ 295 extern void led_trigger_rename_static(const char *name, 296 struct led_trigger *trig); 297 298 #else 299 300 /* Trigger has no members */ 301 struct led_trigger {}; 302 303 /* Trigger inline empty functions */ 304 static inline void led_trigger_register_simple(const char *name, 305 struct led_trigger **trigger) {} 306 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {} 307 static inline void led_trigger_event(struct led_trigger *trigger, 308 enum led_brightness event) {} 309 static inline void led_trigger_blink(struct led_trigger *trigger, 310 unsigned long *delay_on, 311 unsigned long *delay_off) {} 312 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger, 313 unsigned long *delay_on, 314 unsigned long *delay_off, 315 int invert) {} 316 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {} 317 static inline void led_trigger_set(struct led_classdev *led_cdev, 318 struct led_trigger *trigger) {} 319 static inline void led_trigger_remove(struct led_classdev *led_cdev) {} 320 static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 321 { 322 return NULL; 323 } 324 325 #endif /* CONFIG_LEDS_TRIGGERS */ 326 327 /* Trigger specific functions */ 328 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK 329 extern void ledtrig_ide_activity(void); 330 #else 331 static inline void ledtrig_ide_activity(void) {} 332 #endif 333 334 #ifdef CONFIG_LEDS_TRIGGER_MTD 335 extern void ledtrig_mtd_activity(void); 336 #else 337 static inline void ledtrig_mtd_activity(void) {} 338 #endif 339 340 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE) 341 extern void ledtrig_flash_ctrl(bool on); 342 extern void ledtrig_torch_ctrl(bool on); 343 #else 344 static inline void ledtrig_flash_ctrl(bool on) {} 345 static inline void ledtrig_torch_ctrl(bool on) {} 346 #endif 347 348 /* 349 * Generic LED platform data for describing LED names and default triggers. 350 */ 351 struct led_info { 352 const char *name; 353 const char *default_trigger; 354 int flags; 355 }; 356 357 struct led_platform_data { 358 int num_leds; 359 struct led_info *leds; 360 }; 361 362 /* For the leds-gpio driver */ 363 struct gpio_led { 364 const char *name; 365 const char *default_trigger; 366 unsigned gpio; 367 unsigned active_low : 1; 368 unsigned retain_state_suspended : 1; 369 unsigned panic_indicator : 1; 370 unsigned default_state : 2; 371 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ 372 struct gpio_desc *gpiod; 373 }; 374 #define LEDS_GPIO_DEFSTATE_OFF 0 375 #define LEDS_GPIO_DEFSTATE_ON 1 376 #define LEDS_GPIO_DEFSTATE_KEEP 2 377 378 struct gpio_led_platform_data { 379 int num_leds; 380 const struct gpio_led *leds; 381 382 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */ 383 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */ 384 #define GPIO_LED_BLINK 2 /* Please, blink */ 385 int (*gpio_blink_set)(struct gpio_desc *desc, int state, 386 unsigned long *delay_on, 387 unsigned long *delay_off); 388 }; 389 390 struct platform_device *gpio_led_register_device( 391 int id, const struct gpio_led_platform_data *pdata); 392 393 enum cpu_led_event { 394 CPU_LED_IDLE_START, /* CPU enters idle */ 395 CPU_LED_IDLE_END, /* CPU idle ends */ 396 CPU_LED_START, /* Machine starts, especially resume */ 397 CPU_LED_STOP, /* Machine stops, especially suspend */ 398 CPU_LED_HALTED, /* Machine shutdown */ 399 }; 400 #ifdef CONFIG_LEDS_TRIGGER_CPU 401 extern void ledtrig_cpu(enum cpu_led_event evt); 402 #else 403 static inline void ledtrig_cpu(enum cpu_led_event evt) 404 { 405 return; 406 } 407 #endif 408 409 #endif /* __LINUX_LEDS_H_INCLUDED */ 410