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/list.h> 16 #include <linux/mutex.h> 17 #include <linux/rwsem.h> 18 #include <linux/spinlock.h> 19 #include <linux/timer.h> 20 #include <linux/workqueue.h> 21 22 struct device; 23 /* 24 * LED Core 25 */ 26 27 enum led_brightness { 28 LED_OFF = 0, 29 LED_HALF = 127, 30 LED_FULL = 255, 31 }; 32 33 struct led_classdev { 34 const char *name; 35 enum led_brightness brightness; 36 enum led_brightness max_brightness; 37 int flags; 38 39 /* Lower 16 bits reflect status */ 40 #define LED_SUSPENDED (1 << 0) 41 /* Upper 16 bits reflect control information */ 42 #define LED_CORE_SUSPENDRESUME (1 << 16) 43 #define LED_BLINK_ONESHOT (1 << 17) 44 #define LED_BLINK_ONESHOT_STOP (1 << 18) 45 #define LED_BLINK_INVERT (1 << 19) 46 #define LED_SYSFS_DISABLE (1 << 20) 47 #define SET_BRIGHTNESS_ASYNC (1 << 21) 48 #define SET_BRIGHTNESS_SYNC (1 << 22) 49 50 /* Set LED brightness level */ 51 /* Must not sleep, use a workqueue if needed */ 52 void (*brightness_set)(struct led_classdev *led_cdev, 53 enum led_brightness brightness); 54 /* 55 * Set LED brightness level immediately - it can block the caller for 56 * the time required for accessing a LED device register. 57 */ 58 int (*brightness_set_sync)(struct led_classdev *led_cdev, 59 enum led_brightness brightness); 60 /* Get LED brightness level */ 61 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev); 62 63 /* 64 * Activate hardware accelerated blink, delays are in milliseconds 65 * and if both are zero then a sensible default should be chosen. 66 * The call should adjust the timings in that case and if it can't 67 * match the values specified exactly. 68 * Deactivate blinking again when the brightness is set to a fixed 69 * value via the brightness_set() callback. 70 */ 71 int (*blink_set)(struct led_classdev *led_cdev, 72 unsigned long *delay_on, 73 unsigned long *delay_off); 74 75 struct device *dev; 76 const struct attribute_group **groups; 77 78 struct list_head node; /* LED Device list */ 79 const char *default_trigger; /* Trigger to use */ 80 81 unsigned long blink_delay_on, blink_delay_off; 82 struct timer_list blink_timer; 83 int blink_brightness; 84 85 struct work_struct set_brightness_work; 86 int delayed_set_value; 87 88 #ifdef CONFIG_LEDS_TRIGGERS 89 /* Protects the trigger data below */ 90 struct rw_semaphore trigger_lock; 91 92 struct led_trigger *trigger; 93 struct list_head trig_list; 94 void *trigger_data; 95 /* true if activated - deactivate routine uses it to do cleanup */ 96 bool activated; 97 #endif 98 99 /* Ensures consistent access to the LED Flash Class device */ 100 struct mutex led_access; 101 }; 102 103 extern int led_classdev_register(struct device *parent, 104 struct led_classdev *led_cdev); 105 extern void led_classdev_unregister(struct led_classdev *led_cdev); 106 extern void led_classdev_suspend(struct led_classdev *led_cdev); 107 extern void led_classdev_resume(struct led_classdev *led_cdev); 108 109 /** 110 * led_blink_set - set blinking with software fallback 111 * @led_cdev: the LED to start blinking 112 * @delay_on: the time it should be on (in ms) 113 * @delay_off: the time it should ble off (in ms) 114 * 115 * This function makes the LED blink, attempting to use the 116 * hardware acceleration if possible, but falling back to 117 * software blinking if there is no hardware blinking or if 118 * the LED refuses the passed values. 119 * 120 * Note that if software blinking is active, simply calling 121 * led_cdev->brightness_set() will not stop the blinking, 122 * use led_classdev_brightness_set() instead. 123 */ 124 extern void led_blink_set(struct led_classdev *led_cdev, 125 unsigned long *delay_on, 126 unsigned long *delay_off); 127 /** 128 * led_blink_set_oneshot - do a oneshot software blink 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 * @invert: blink off, then on, leaving the led on 133 * 134 * This function makes the LED blink one time for delay_on + 135 * delay_off time, ignoring the request if another one-shot 136 * blink is already in progress. 137 * 138 * If invert is set, led blinks for delay_off first, then for 139 * delay_on and leave the led on after the on-off cycle. 140 */ 141 extern void led_blink_set_oneshot(struct led_classdev *led_cdev, 142 unsigned long *delay_on, 143 unsigned long *delay_off, 144 int invert); 145 /** 146 * led_set_brightness - set LED brightness 147 * @led_cdev: the LED to set 148 * @brightness: the brightness to set it to 149 * 150 * Set an LED's brightness, and, if necessary, cancel the 151 * software blink timer that implements blinking when the 152 * hardware doesn't. 153 */ 154 extern void led_set_brightness(struct led_classdev *led_cdev, 155 enum led_brightness brightness); 156 /** 157 * led_update_brightness - update LED brightness 158 * @led_cdev: the LED to query 159 * 160 * Get an LED's current brightness and update led_cdev->brightness 161 * member with the obtained value. 162 * 163 * Returns: 0 on success or negative error value on failure 164 */ 165 extern int led_update_brightness(struct led_classdev *led_cdev); 166 167 /** 168 * led_sysfs_disable - disable LED sysfs interface 169 * @led_cdev: the LED to set 170 * 171 * Disable the led_cdev's sysfs interface. 172 */ 173 extern void led_sysfs_disable(struct led_classdev *led_cdev); 174 175 /** 176 * led_sysfs_enable - enable LED sysfs interface 177 * @led_cdev: the LED to set 178 * 179 * Enable the led_cdev's sysfs interface. 180 */ 181 extern void led_sysfs_enable(struct led_classdev *led_cdev); 182 183 /** 184 * led_sysfs_is_disabled - check if LED sysfs interface is disabled 185 * @led_cdev: the LED to query 186 * 187 * Returns: true if the led_cdev's sysfs interface is disabled. 188 */ 189 static inline bool led_sysfs_is_disabled(struct led_classdev *led_cdev) 190 { 191 return led_cdev->flags & LED_SYSFS_DISABLE; 192 } 193 194 /* 195 * LED Triggers 196 */ 197 /* Registration functions for simple triggers */ 198 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x; 199 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x; 200 201 #ifdef CONFIG_LEDS_TRIGGERS 202 203 #define TRIG_NAME_MAX 50 204 205 struct led_trigger { 206 /* Trigger Properties */ 207 const char *name; 208 void (*activate)(struct led_classdev *led_cdev); 209 void (*deactivate)(struct led_classdev *led_cdev); 210 211 /* LEDs under control by this trigger (for simple triggers) */ 212 rwlock_t leddev_list_lock; 213 struct list_head led_cdevs; 214 215 /* Link to next registered trigger */ 216 struct list_head next_trig; 217 }; 218 219 /* Registration functions for complex triggers */ 220 extern int led_trigger_register(struct led_trigger *trigger); 221 extern void led_trigger_unregister(struct led_trigger *trigger); 222 223 extern void led_trigger_register_simple(const char *name, 224 struct led_trigger **trigger); 225 extern void led_trigger_unregister_simple(struct led_trigger *trigger); 226 extern void led_trigger_event(struct led_trigger *trigger, 227 enum led_brightness event); 228 extern void led_trigger_blink(struct led_trigger *trigger, 229 unsigned long *delay_on, 230 unsigned long *delay_off); 231 extern void led_trigger_blink_oneshot(struct led_trigger *trigger, 232 unsigned long *delay_on, 233 unsigned long *delay_off, 234 int invert); 235 /** 236 * led_trigger_rename_static - rename a trigger 237 * @name: the new trigger name 238 * @trig: the LED trigger to rename 239 * 240 * Change a LED trigger name by copying the string passed in 241 * name into current trigger name, which MUST be large 242 * enough for the new string. 243 * 244 * Note that name must NOT point to the same string used 245 * during LED registration, as that could lead to races. 246 * 247 * This is meant to be used on triggers with statically 248 * allocated name. 249 */ 250 extern void led_trigger_rename_static(const char *name, 251 struct led_trigger *trig); 252 253 #else 254 255 /* Trigger has no members */ 256 struct led_trigger {}; 257 258 /* Trigger inline empty functions */ 259 static inline void led_trigger_register_simple(const char *name, 260 struct led_trigger **trigger) {} 261 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {} 262 static inline void led_trigger_event(struct led_trigger *trigger, 263 enum led_brightness event) {} 264 #endif /* CONFIG_LEDS_TRIGGERS */ 265 266 /* Trigger specific functions */ 267 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK 268 extern void ledtrig_ide_activity(void); 269 #else 270 static inline void ledtrig_ide_activity(void) {} 271 #endif 272 273 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE) 274 extern void ledtrig_flash_ctrl(bool on); 275 extern void ledtrig_torch_ctrl(bool on); 276 #else 277 static inline void ledtrig_flash_ctrl(bool on) {} 278 static inline void ledtrig_torch_ctrl(bool on) {} 279 #endif 280 281 /* 282 * Generic LED platform data for describing LED names and default triggers. 283 */ 284 struct led_info { 285 const char *name; 286 const char *default_trigger; 287 int flags; 288 }; 289 290 struct led_platform_data { 291 int num_leds; 292 struct led_info *leds; 293 }; 294 295 /* For the leds-gpio driver */ 296 struct gpio_led { 297 const char *name; 298 const char *default_trigger; 299 unsigned gpio; 300 unsigned active_low : 1; 301 unsigned retain_state_suspended : 1; 302 unsigned default_state : 2; 303 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ 304 struct gpio_desc *gpiod; 305 }; 306 #define LEDS_GPIO_DEFSTATE_OFF 0 307 #define LEDS_GPIO_DEFSTATE_ON 1 308 #define LEDS_GPIO_DEFSTATE_KEEP 2 309 310 struct gpio_led_platform_data { 311 int num_leds; 312 const struct gpio_led *leds; 313 314 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */ 315 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */ 316 #define GPIO_LED_BLINK 2 /* Please, blink */ 317 int (*gpio_blink_set)(struct gpio_desc *desc, int state, 318 unsigned long *delay_on, 319 unsigned long *delay_off); 320 }; 321 322 struct platform_device *gpio_led_register_device( 323 int id, const struct gpio_led_platform_data *pdata); 324 325 enum cpu_led_event { 326 CPU_LED_IDLE_START, /* CPU enters idle */ 327 CPU_LED_IDLE_END, /* CPU idle ends */ 328 CPU_LED_START, /* Machine starts, especially resume */ 329 CPU_LED_STOP, /* Machine stops, especially suspend */ 330 CPU_LED_HALTED, /* Machine shutdown */ 331 }; 332 #ifdef CONFIG_LEDS_TRIGGER_CPU 333 extern void ledtrig_cpu(enum cpu_led_event evt); 334 #else 335 static inline void ledtrig_cpu(enum cpu_led_event evt) 336 { 337 return; 338 } 339 #endif 340 341 #endif /* __LINUX_LEDS_H_INCLUDED */ 342