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