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 /* Upper 16 bits reflect control information */ 43 #define LED_CORE_SUSPENDRESUME (1 << 16) 44 #define LED_BLINK_ONESHOT (1 << 17) 45 #define LED_BLINK_ONESHOT_STOP (1 << 18) 46 #define LED_BLINK_INVERT (1 << 19) 47 #define LED_BLINK_BRIGHTNESS_CHANGE (1 << 20) 48 #define LED_BLINK_DISABLE (1 << 21) 49 #define LED_SYSFS_DISABLE (1 << 22) 50 #define LED_DEV_CAP_FLASH (1 << 23) 51 52 /* Set LED brightness level */ 53 /* Must not sleep, use a workqueue if needed */ 54 void (*brightness_set)(struct led_classdev *led_cdev, 55 enum led_brightness brightness); 56 /* 57 * Set LED brightness level immediately - it can block the caller for 58 * the time required for accessing a LED device register. 59 */ 60 int (*brightness_set_blocking)(struct led_classdev *led_cdev, 61 enum led_brightness brightness); 62 /* Get LED brightness level */ 63 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev); 64 65 /* 66 * Activate hardware accelerated blink, delays are in milliseconds 67 * and if both are zero then a sensible default should be chosen. 68 * The call should adjust the timings in that case and if it can't 69 * match the values specified exactly. 70 * Deactivate blinking again when the brightness is set to a fixed 71 * value via the brightness_set() callback. 72 */ 73 int (*blink_set)(struct led_classdev *led_cdev, 74 unsigned long *delay_on, 75 unsigned long *delay_off); 76 77 struct device *dev; 78 const struct attribute_group **groups; 79 80 struct list_head node; /* LED Device list */ 81 const char *default_trigger; /* Trigger to use */ 82 83 unsigned long blink_delay_on, blink_delay_off; 84 struct timer_list blink_timer; 85 int blink_brightness; 86 void (*flash_resume)(struct led_classdev *led_cdev); 87 88 struct work_struct set_brightness_work; 89 int delayed_set_value; 90 91 #ifdef CONFIG_LEDS_TRIGGERS 92 /* Protects the trigger data below */ 93 struct rw_semaphore trigger_lock; 94 95 struct led_trigger *trigger; 96 struct list_head trig_list; 97 void *trigger_data; 98 /* true if activated - deactivate routine uses it to do cleanup */ 99 bool activated; 100 #endif 101 102 /* Ensures consistent access to the LED Flash Class device */ 103 struct mutex led_access; 104 }; 105 106 extern int led_classdev_register(struct device *parent, 107 struct led_classdev *led_cdev); 108 extern int devm_led_classdev_register(struct device *parent, 109 struct led_classdev *led_cdev); 110 extern void led_classdev_unregister(struct led_classdev *led_cdev); 111 extern void devm_led_classdev_unregister(struct device *parent, 112 struct led_classdev *led_cdev); 113 extern void led_classdev_suspend(struct led_classdev *led_cdev); 114 extern void led_classdev_resume(struct led_classdev *led_cdev); 115 116 /** 117 * led_blink_set - set blinking with software fallback 118 * @led_cdev: the LED to start blinking 119 * @delay_on: the time it should be on (in ms) 120 * @delay_off: the time it should ble off (in ms) 121 * 122 * This function makes the LED blink, attempting to use the 123 * hardware acceleration if possible, but falling back to 124 * software blinking if there is no hardware blinking or if 125 * the LED refuses the passed values. 126 * 127 * Note that if software blinking is active, simply calling 128 * led_cdev->brightness_set() will not stop the blinking, 129 * use led_classdev_brightness_set() instead. 130 */ 131 extern void led_blink_set(struct led_classdev *led_cdev, 132 unsigned long *delay_on, 133 unsigned long *delay_off); 134 /** 135 * led_blink_set_oneshot - do a oneshot software blink 136 * @led_cdev: the LED to start blinking 137 * @delay_on: the time it should be on (in ms) 138 * @delay_off: the time it should ble off (in ms) 139 * @invert: blink off, then on, leaving the led on 140 * 141 * This function makes the LED blink one time for delay_on + 142 * delay_off time, ignoring the request if another one-shot 143 * blink is already in progress. 144 * 145 * If invert is set, led blinks for delay_off first, then for 146 * delay_on and leave the led on after the on-off cycle. 147 */ 148 extern void led_blink_set_oneshot(struct led_classdev *led_cdev, 149 unsigned long *delay_on, 150 unsigned long *delay_off, 151 int invert); 152 /** 153 * led_set_brightness - set LED brightness 154 * @led_cdev: the LED to set 155 * @brightness: the brightness to set it to 156 * 157 * Set an LED's brightness, and, if necessary, cancel the 158 * software blink timer that implements blinking when the 159 * hardware doesn't. This function is guaranteed not to sleep. 160 */ 161 extern void led_set_brightness(struct led_classdev *led_cdev, 162 enum led_brightness brightness); 163 164 /** 165 * led_set_brightness_sync - set LED brightness synchronously 166 * @led_cdev: the LED to set 167 * @brightness: the brightness to set it to 168 * 169 * Set an LED's brightness immediately. This function will block 170 * the caller for the time required for accessing device registers, 171 * and it can sleep. 172 * 173 * Returns: 0 on success or negative error value on failure 174 */ 175 extern int led_set_brightness_sync(struct led_classdev *led_cdev, 176 enum led_brightness value); 177 178 /** 179 * led_update_brightness - update LED brightness 180 * @led_cdev: the LED to query 181 * 182 * Get an LED's current brightness and update led_cdev->brightness 183 * member with the obtained value. 184 * 185 * Returns: 0 on success or negative error value on failure 186 */ 187 extern int led_update_brightness(struct led_classdev *led_cdev); 188 189 /** 190 * led_sysfs_disable - disable LED sysfs interface 191 * @led_cdev: the LED to set 192 * 193 * Disable the led_cdev's sysfs interface. 194 */ 195 extern void led_sysfs_disable(struct led_classdev *led_cdev); 196 197 /** 198 * led_sysfs_enable - enable LED sysfs interface 199 * @led_cdev: the LED to set 200 * 201 * Enable the led_cdev's sysfs interface. 202 */ 203 extern void led_sysfs_enable(struct led_classdev *led_cdev); 204 205 /** 206 * led_sysfs_is_disabled - check if LED sysfs interface is disabled 207 * @led_cdev: the LED to query 208 * 209 * Returns: true if the led_cdev's sysfs interface is disabled. 210 */ 211 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev) 212 { 213 return led_cdev->flags & LED_SYSFS_DISABLE; 214 } 215 216 /* 217 * LED Triggers 218 */ 219 /* Registration functions for simple triggers */ 220 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x; 221 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x; 222 223 #ifdef CONFIG_LEDS_TRIGGERS 224 225 #define TRIG_NAME_MAX 50 226 227 struct led_trigger { 228 /* Trigger Properties */ 229 const char *name; 230 void (*activate)(struct led_classdev *led_cdev); 231 void (*deactivate)(struct led_classdev *led_cdev); 232 233 /* LEDs under control by this trigger (for simple triggers) */ 234 rwlock_t leddev_list_lock; 235 struct list_head led_cdevs; 236 237 /* Link to next registered trigger */ 238 struct list_head next_trig; 239 }; 240 241 ssize_t led_trigger_store(struct device *dev, struct device_attribute *attr, 242 const char *buf, size_t count); 243 ssize_t led_trigger_show(struct device *dev, struct device_attribute *attr, 244 char *buf); 245 246 /* Registration functions for complex triggers */ 247 extern int led_trigger_register(struct led_trigger *trigger); 248 extern void led_trigger_unregister(struct led_trigger *trigger); 249 extern int devm_led_trigger_register(struct device *dev, 250 struct led_trigger *trigger); 251 252 extern void led_trigger_register_simple(const char *name, 253 struct led_trigger **trigger); 254 extern void led_trigger_unregister_simple(struct led_trigger *trigger); 255 extern void led_trigger_event(struct led_trigger *trigger, 256 enum led_brightness event); 257 extern void led_trigger_blink(struct led_trigger *trigger, 258 unsigned long *delay_on, 259 unsigned long *delay_off); 260 extern void led_trigger_blink_oneshot(struct led_trigger *trigger, 261 unsigned long *delay_on, 262 unsigned long *delay_off, 263 int invert); 264 extern void led_trigger_set_default(struct led_classdev *led_cdev); 265 extern void led_trigger_set(struct led_classdev *led_cdev, 266 struct led_trigger *trigger); 267 extern void led_trigger_remove(struct led_classdev *led_cdev); 268 269 static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 270 { 271 return led_cdev->trigger_data; 272 } 273 274 /** 275 * led_trigger_rename_static - rename a trigger 276 * @name: the new trigger name 277 * @trig: the LED trigger to rename 278 * 279 * Change a LED trigger name by copying the string passed in 280 * name into current trigger name, which MUST be large 281 * enough for the new string. 282 * 283 * Note that name must NOT point to the same string used 284 * during LED registration, as that could lead to races. 285 * 286 * This is meant to be used on triggers with statically 287 * allocated name. 288 */ 289 extern void led_trigger_rename_static(const char *name, 290 struct led_trigger *trig); 291 292 #else 293 294 /* Trigger has no members */ 295 struct led_trigger {}; 296 297 /* Trigger inline empty functions */ 298 static inline void led_trigger_register_simple(const char *name, 299 struct led_trigger **trigger) {} 300 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {} 301 static inline void led_trigger_event(struct led_trigger *trigger, 302 enum led_brightness event) {} 303 static inline void led_trigger_blink(struct led_trigger *trigger, 304 unsigned long *delay_on, 305 unsigned long *delay_off) {} 306 static inline void led_trigger_blink_oneshot(struct led_trigger *trigger, 307 unsigned long *delay_on, 308 unsigned long *delay_off, 309 int invert) {} 310 static inline void led_trigger_set_default(struct led_classdev *led_cdev) {} 311 static inline void led_trigger_set(struct led_classdev *led_cdev, 312 struct led_trigger *trigger) {} 313 static inline void led_trigger_remove(struct led_classdev *led_cdev) {} 314 static inline void *led_get_trigger_data(struct led_classdev *led_cdev) 315 { 316 return NULL; 317 } 318 319 #endif /* CONFIG_LEDS_TRIGGERS */ 320 321 /* Trigger specific functions */ 322 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK 323 extern void ledtrig_ide_activity(void); 324 #else 325 static inline void ledtrig_ide_activity(void) {} 326 #endif 327 328 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE) 329 extern void ledtrig_flash_ctrl(bool on); 330 extern void ledtrig_torch_ctrl(bool on); 331 #else 332 static inline void ledtrig_flash_ctrl(bool on) {} 333 static inline void ledtrig_torch_ctrl(bool on) {} 334 #endif 335 336 /* 337 * Generic LED platform data for describing LED names and default triggers. 338 */ 339 struct led_info { 340 const char *name; 341 const char *default_trigger; 342 int flags; 343 }; 344 345 struct led_platform_data { 346 int num_leds; 347 struct led_info *leds; 348 }; 349 350 /* For the leds-gpio driver */ 351 struct gpio_led { 352 const char *name; 353 const char *default_trigger; 354 unsigned gpio; 355 unsigned active_low : 1; 356 unsigned retain_state_suspended : 1; 357 unsigned default_state : 2; 358 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ 359 struct gpio_desc *gpiod; 360 }; 361 #define LEDS_GPIO_DEFSTATE_OFF 0 362 #define LEDS_GPIO_DEFSTATE_ON 1 363 #define LEDS_GPIO_DEFSTATE_KEEP 2 364 365 struct gpio_led_platform_data { 366 int num_leds; 367 const struct gpio_led *leds; 368 369 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */ 370 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */ 371 #define GPIO_LED_BLINK 2 /* Please, blink */ 372 int (*gpio_blink_set)(struct gpio_desc *desc, int state, 373 unsigned long *delay_on, 374 unsigned long *delay_off); 375 }; 376 377 struct platform_device *gpio_led_register_device( 378 int id, const struct gpio_led_platform_data *pdata); 379 380 enum cpu_led_event { 381 CPU_LED_IDLE_START, /* CPU enters idle */ 382 CPU_LED_IDLE_END, /* CPU idle ends */ 383 CPU_LED_START, /* Machine starts, especially resume */ 384 CPU_LED_STOP, /* Machine stops, especially suspend */ 385 CPU_LED_HALTED, /* Machine shutdown */ 386 }; 387 #ifdef CONFIG_LEDS_TRIGGER_CPU 388 extern void ledtrig_cpu(enum cpu_led_event evt); 389 #else 390 static inline void ledtrig_cpu(enum cpu_led_event evt) 391 { 392 return; 393 } 394 #endif 395 396 #endif /* __LINUX_LEDS_H_INCLUDED */ 397