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/rwsem.h> 17 #include <linux/spinlock.h> 18 #include <linux/timer.h> 19 #include <linux/workqueue.h> 20 21 struct device; 22 /* 23 * LED Core 24 */ 25 26 enum led_brightness { 27 LED_OFF = 0, 28 LED_HALF = 127, 29 LED_FULL = 255, 30 }; 31 32 struct led_classdev { 33 const char *name; 34 enum led_brightness brightness; 35 enum led_brightness max_brightness; 36 int flags; 37 38 /* Lower 16 bits reflect status */ 39 #define LED_SUSPENDED (1 << 0) 40 /* Upper 16 bits reflect control information */ 41 #define LED_CORE_SUSPENDRESUME (1 << 16) 42 #define LED_BLINK_ONESHOT (1 << 17) 43 #define LED_BLINK_ONESHOT_STOP (1 << 18) 44 #define LED_BLINK_INVERT (1 << 19) 45 46 /* Set LED brightness level */ 47 /* Must not sleep, use a workqueue if needed */ 48 void (*brightness_set)(struct led_classdev *led_cdev, 49 enum led_brightness brightness); 50 /* Get LED brightness level */ 51 enum led_brightness (*brightness_get)(struct led_classdev *led_cdev); 52 53 /* 54 * Activate hardware accelerated blink, delays are in milliseconds 55 * and if both are zero then a sensible default should be chosen. 56 * The call should adjust the timings in that case and if it can't 57 * match the values specified exactly. 58 * Deactivate blinking again when the brightness is set to a fixed 59 * value via the brightness_set() callback. 60 */ 61 int (*blink_set)(struct led_classdev *led_cdev, 62 unsigned long *delay_on, 63 unsigned long *delay_off); 64 65 struct device *dev; 66 const struct attribute_group **groups; 67 68 struct list_head node; /* LED Device list */ 69 const char *default_trigger; /* Trigger to use */ 70 71 unsigned long blink_delay_on, blink_delay_off; 72 struct timer_list blink_timer; 73 int blink_brightness; 74 75 struct work_struct set_brightness_work; 76 int delayed_set_value; 77 78 #ifdef CONFIG_LEDS_TRIGGERS 79 /* Protects the trigger data below */ 80 struct rw_semaphore trigger_lock; 81 82 struct led_trigger *trigger; 83 struct list_head trig_list; 84 void *trigger_data; 85 /* true if activated - deactivate routine uses it to do cleanup */ 86 bool activated; 87 #endif 88 }; 89 90 extern int led_classdev_register(struct device *parent, 91 struct led_classdev *led_cdev); 92 extern void led_classdev_unregister(struct led_classdev *led_cdev); 93 extern void led_classdev_suspend(struct led_classdev *led_cdev); 94 extern void led_classdev_resume(struct led_classdev *led_cdev); 95 96 /** 97 * led_blink_set - set blinking with software fallback 98 * @led_cdev: the LED to start blinking 99 * @delay_on: the time it should be on (in ms) 100 * @delay_off: the time it should ble off (in ms) 101 * 102 * This function makes the LED blink, attempting to use the 103 * hardware acceleration if possible, but falling back to 104 * software blinking if there is no hardware blinking or if 105 * the LED refuses the passed values. 106 * 107 * Note that if software blinking is active, simply calling 108 * led_cdev->brightness_set() will not stop the blinking, 109 * use led_classdev_brightness_set() instead. 110 */ 111 extern void led_blink_set(struct led_classdev *led_cdev, 112 unsigned long *delay_on, 113 unsigned long *delay_off); 114 /** 115 * led_blink_set_oneshot - do a oneshot software blink 116 * @led_cdev: the LED to start blinking 117 * @delay_on: the time it should be on (in ms) 118 * @delay_off: the time it should ble off (in ms) 119 * @invert: blink off, then on, leaving the led on 120 * 121 * This function makes the LED blink one time for delay_on + 122 * delay_off time, ignoring the request if another one-shot 123 * blink is already in progress. 124 * 125 * If invert is set, led blinks for delay_off first, then for 126 * delay_on and leave the led on after the on-off cycle. 127 */ 128 extern void led_blink_set_oneshot(struct led_classdev *led_cdev, 129 unsigned long *delay_on, 130 unsigned long *delay_off, 131 int invert); 132 /** 133 * led_set_brightness - set LED brightness 134 * @led_cdev: the LED to set 135 * @brightness: the brightness to set it to 136 * 137 * Set an LED's brightness, and, if necessary, cancel the 138 * software blink timer that implements blinking when the 139 * hardware doesn't. 140 */ 141 extern void led_set_brightness(struct led_classdev *led_cdev, 142 enum led_brightness brightness); 143 /** 144 * led_update_brightness - update LED brightness 145 * @led_cdev: the LED to query 146 * 147 * Get an LED's current brightness and update led_cdev->brightness 148 * member with the obtained value. 149 * 150 * Returns: 0 on success or negative error value on failure 151 */ 152 extern int led_update_brightness(struct led_classdev *led_cdev); 153 154 /* 155 * LED Triggers 156 */ 157 /* Registration functions for simple triggers */ 158 #define DEFINE_LED_TRIGGER(x) static struct led_trigger *x; 159 #define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x; 160 161 #ifdef CONFIG_LEDS_TRIGGERS 162 163 #define TRIG_NAME_MAX 50 164 165 struct led_trigger { 166 /* Trigger Properties */ 167 const char *name; 168 void (*activate)(struct led_classdev *led_cdev); 169 void (*deactivate)(struct led_classdev *led_cdev); 170 171 /* LEDs under control by this trigger (for simple triggers) */ 172 rwlock_t leddev_list_lock; 173 struct list_head led_cdevs; 174 175 /* Link to next registered trigger */ 176 struct list_head next_trig; 177 }; 178 179 /* Registration functions for complex triggers */ 180 extern int led_trigger_register(struct led_trigger *trigger); 181 extern void led_trigger_unregister(struct led_trigger *trigger); 182 183 extern void led_trigger_register_simple(const char *name, 184 struct led_trigger **trigger); 185 extern void led_trigger_unregister_simple(struct led_trigger *trigger); 186 extern void led_trigger_event(struct led_trigger *trigger, 187 enum led_brightness event); 188 extern void led_trigger_blink(struct led_trigger *trigger, 189 unsigned long *delay_on, 190 unsigned long *delay_off); 191 extern void led_trigger_blink_oneshot(struct led_trigger *trigger, 192 unsigned long *delay_on, 193 unsigned long *delay_off, 194 int invert); 195 /** 196 * led_trigger_rename_static - rename a trigger 197 * @name: the new trigger name 198 * @trig: the LED trigger to rename 199 * 200 * Change a LED trigger name by copying the string passed in 201 * name into current trigger name, which MUST be large 202 * enough for the new string. 203 * 204 * Note that name must NOT point to the same string used 205 * during LED registration, as that could lead to races. 206 * 207 * This is meant to be used on triggers with statically 208 * allocated name. 209 */ 210 extern void led_trigger_rename_static(const char *name, 211 struct led_trigger *trig); 212 213 #else 214 215 /* Trigger has no members */ 216 struct led_trigger {}; 217 218 /* Trigger inline empty functions */ 219 static inline void led_trigger_register_simple(const char *name, 220 struct led_trigger **trigger) {} 221 static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {} 222 static inline void led_trigger_event(struct led_trigger *trigger, 223 enum led_brightness event) {} 224 #endif /* CONFIG_LEDS_TRIGGERS */ 225 226 /* Trigger specific functions */ 227 #ifdef CONFIG_LEDS_TRIGGER_IDE_DISK 228 extern void ledtrig_ide_activity(void); 229 #else 230 static inline void ledtrig_ide_activity(void) {} 231 #endif 232 233 #if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE) 234 extern void ledtrig_flash_ctrl(bool on); 235 extern void ledtrig_torch_ctrl(bool on); 236 #else 237 static inline void ledtrig_flash_ctrl(bool on) {} 238 static inline void ledtrig_torch_ctrl(bool on) {} 239 #endif 240 241 /* 242 * Generic LED platform data for describing LED names and default triggers. 243 */ 244 struct led_info { 245 const char *name; 246 const char *default_trigger; 247 int flags; 248 }; 249 250 struct led_platform_data { 251 int num_leds; 252 struct led_info *leds; 253 }; 254 255 /* For the leds-gpio driver */ 256 struct gpio_led { 257 const char *name; 258 const char *default_trigger; 259 unsigned gpio; 260 unsigned active_low : 1; 261 unsigned retain_state_suspended : 1; 262 unsigned default_state : 2; 263 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */ 264 }; 265 #define LEDS_GPIO_DEFSTATE_OFF 0 266 #define LEDS_GPIO_DEFSTATE_ON 1 267 #define LEDS_GPIO_DEFSTATE_KEEP 2 268 269 struct gpio_led_platform_data { 270 int num_leds; 271 const struct gpio_led *leds; 272 273 #define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */ 274 #define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */ 275 #define GPIO_LED_BLINK 2 /* Please, blink */ 276 int (*gpio_blink_set)(unsigned gpio, int state, 277 unsigned long *delay_on, 278 unsigned long *delay_off); 279 }; 280 281 struct platform_device *gpio_led_register_device( 282 int id, const struct gpio_led_platform_data *pdata); 283 284 enum cpu_led_event { 285 CPU_LED_IDLE_START, /* CPU enters idle */ 286 CPU_LED_IDLE_END, /* CPU idle ends */ 287 CPU_LED_START, /* Machine starts, especially resume */ 288 CPU_LED_STOP, /* Machine stops, especially suspend */ 289 CPU_LED_HALTED, /* Machine shutdown */ 290 }; 291 #ifdef CONFIG_LEDS_TRIGGER_CPU 292 extern void ledtrig_cpu(enum cpu_led_event evt); 293 #else 294 static inline void ledtrig_cpu(enum cpu_led_event evt) 295 { 296 return; 297 } 298 #endif 299 300 #endif /* __LINUX_LEDS_H_INCLUDED */ 301