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