Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * Driver model for leds and led triggers
3 *
4 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
5 * Copyright (C) 2005 Richard Purdie <rpurdie@openedhand.com>
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/spinlock.h>
17#include <linux/rwsem.h>
18#include <linux/timer.h>
19#include <linux/workqueue.h>
20
21struct device;
22/*
23 * LED Core
24 */
25
26enum led_brightness {
27 LED_OFF = 0,
28 LED_HALF = 127,
29 LED_FULL = 255,
30};
31
32struct led_classdev {
33 const char *name;
34 int brightness;
35 int 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 struct list_head node; /* LED Device list */
67 const char *default_trigger; /* Trigger to use */
68
69 unsigned long blink_delay_on, blink_delay_off;
70 struct timer_list blink_timer;
71 int blink_brightness;
72
73 struct work_struct set_brightness_work;
74 int delayed_set_value;
75
76#ifdef CONFIG_LEDS_TRIGGERS
77 /* Protects the trigger data below */
78 struct rw_semaphore trigger_lock;
79
80 struct led_trigger *trigger;
81 struct list_head trig_list;
82 void *trigger_data;
83 /* true if activated - deactivate routine uses it to do cleanup */
84 bool activated;
85#endif
86};
87
88extern int led_classdev_register(struct device *parent,
89 struct led_classdev *led_cdev);
90extern void led_classdev_unregister(struct led_classdev *led_cdev);
91extern void led_classdev_suspend(struct led_classdev *led_cdev);
92extern void led_classdev_resume(struct led_classdev *led_cdev);
93
94/**
95 * led_blink_set - set blinking with software fallback
96 * @led_cdev: the LED to start blinking
97 * @delay_on: the time it should be on (in ms)
98 * @delay_off: the time it should ble off (in ms)
99 *
100 * This function makes the LED blink, attempting to use the
101 * hardware acceleration if possible, but falling back to
102 * software blinking if there is no hardware blinking or if
103 * the LED refuses the passed values.
104 *
105 * Note that if software blinking is active, simply calling
106 * led_cdev->brightness_set() will not stop the blinking,
107 * use led_classdev_brightness_set() instead.
108 */
109extern void led_blink_set(struct led_classdev *led_cdev,
110 unsigned long *delay_on,
111 unsigned long *delay_off);
112/**
113 * led_blink_set_oneshot - do a oneshot software blink
114 * @led_cdev: the LED to start blinking
115 * @delay_on: the time it should be on (in ms)
116 * @delay_off: the time it should ble off (in ms)
117 * @invert: blink off, then on, leaving the led on
118 *
119 * This function makes the LED blink one time for delay_on +
120 * delay_off time, ignoring the request if another one-shot
121 * blink is already in progress.
122 *
123 * If invert is set, led blinks for delay_off first, then for
124 * delay_on and leave the led on after the on-off cycle.
125 */
126extern void led_blink_set_oneshot(struct led_classdev *led_cdev,
127 unsigned long *delay_on,
128 unsigned long *delay_off,
129 int invert);
130/**
131 * led_set_brightness - set LED brightness
132 * @led_cdev: the LED to set
133 * @brightness: the brightness to set it to
134 *
135 * Set an LED's brightness, and, if necessary, cancel the
136 * software blink timer that implements blinking when the
137 * hardware doesn't.
138 */
139extern void led_set_brightness(struct led_classdev *led_cdev,
140 enum led_brightness brightness);
141
142/*
143 * LED Triggers
144 */
145/* Registration functions for simple triggers */
146#define DEFINE_LED_TRIGGER(x) static struct led_trigger *x;
147#define DEFINE_LED_TRIGGER_GLOBAL(x) struct led_trigger *x;
148
149#ifdef CONFIG_LEDS_TRIGGERS
150
151#define TRIG_NAME_MAX 50
152
153struct led_trigger {
154 /* Trigger Properties */
155 const char *name;
156 void (*activate)(struct led_classdev *led_cdev);
157 void (*deactivate)(struct led_classdev *led_cdev);
158
159 /* LEDs under control by this trigger (for simple triggers) */
160 rwlock_t leddev_list_lock;
161 struct list_head led_cdevs;
162
163 /* Link to next registered trigger */
164 struct list_head next_trig;
165};
166
167/* Registration functions for complex triggers */
168extern int led_trigger_register(struct led_trigger *trigger);
169extern void led_trigger_unregister(struct led_trigger *trigger);
170
171extern void led_trigger_register_simple(const char *name,
172 struct led_trigger **trigger);
173extern void led_trigger_unregister_simple(struct led_trigger *trigger);
174extern void led_trigger_event(struct led_trigger *trigger,
175 enum led_brightness event);
176extern void led_trigger_blink(struct led_trigger *trigger,
177 unsigned long *delay_on,
178 unsigned long *delay_off);
179extern void led_trigger_blink_oneshot(struct led_trigger *trigger,
180 unsigned long *delay_on,
181 unsigned long *delay_off,
182 int invert);
183/**
184 * led_trigger_rename_static - rename a trigger
185 * @name: the new trigger name
186 * @trig: the LED trigger to rename
187 *
188 * Change a LED trigger name by copying the string passed in
189 * name into current trigger name, which MUST be large
190 * enough for the new string.
191 *
192 * Note that name must NOT point to the same string used
193 * during LED registration, as that could lead to races.
194 *
195 * This is meant to be used on triggers with statically
196 * allocated name.
197 */
198extern void led_trigger_rename_static(const char *name,
199 struct led_trigger *trig);
200
201#else
202
203/* Trigger has no members */
204struct led_trigger {};
205
206/* Trigger inline empty functions */
207static inline void led_trigger_register_simple(const char *name,
208 struct led_trigger **trigger) {}
209static inline void led_trigger_unregister_simple(struct led_trigger *trigger) {}
210static inline void led_trigger_event(struct led_trigger *trigger,
211 enum led_brightness event) {}
212#endif /* CONFIG_LEDS_TRIGGERS */
213
214/* Trigger specific functions */
215#ifdef CONFIG_LEDS_TRIGGER_IDE_DISK
216extern void ledtrig_ide_activity(void);
217#else
218static inline void ledtrig_ide_activity(void) {}
219#endif
220
221#if defined(CONFIG_LEDS_TRIGGER_CAMERA) || defined(CONFIG_LEDS_TRIGGER_CAMERA_MODULE)
222extern void ledtrig_flash_ctrl(bool on);
223extern void ledtrig_torch_ctrl(bool on);
224#else
225static inline void ledtrig_flash_ctrl(bool on) {}
226static inline void ledtrig_torch_ctrl(bool on) {}
227#endif
228
229/*
230 * Generic LED platform data for describing LED names and default triggers.
231 */
232struct led_info {
233 const char *name;
234 const char *default_trigger;
235 int flags;
236};
237
238struct led_platform_data {
239 int num_leds;
240 struct led_info *leds;
241};
242
243/* For the leds-gpio driver */
244struct gpio_led {
245 const char *name;
246 const char *default_trigger;
247 unsigned gpio;
248 unsigned active_low : 1;
249 unsigned retain_state_suspended : 1;
250 unsigned default_state : 2;
251 /* default_state should be one of LEDS_GPIO_DEFSTATE_(ON|OFF|KEEP) */
252};
253#define LEDS_GPIO_DEFSTATE_OFF 0
254#define LEDS_GPIO_DEFSTATE_ON 1
255#define LEDS_GPIO_DEFSTATE_KEEP 2
256
257struct gpio_led_platform_data {
258 int num_leds;
259 const struct gpio_led *leds;
260
261#define GPIO_LED_NO_BLINK_LOW 0 /* No blink GPIO state low */
262#define GPIO_LED_NO_BLINK_HIGH 1 /* No blink GPIO state high */
263#define GPIO_LED_BLINK 2 /* Please, blink */
264 int (*gpio_blink_set)(unsigned gpio, int state,
265 unsigned long *delay_on,
266 unsigned long *delay_off);
267};
268
269struct platform_device *gpio_led_register_device(
270 int id, const struct gpio_led_platform_data *pdata);
271
272enum cpu_led_event {
273 CPU_LED_IDLE_START, /* CPU enters idle */
274 CPU_LED_IDLE_END, /* CPU idle ends */
275 CPU_LED_START, /* Machine starts, especially resume */
276 CPU_LED_STOP, /* Machine stops, especially suspend */
277 CPU_LED_HALTED, /* Machine shutdown */
278};
279#ifdef CONFIG_LEDS_TRIGGER_CPU
280extern void ledtrig_cpu(enum cpu_led_event evt);
281#else
282static inline void ledtrig_cpu(enum cpu_led_event evt)
283{
284 return;
285}
286#endif
287
288#endif /* __LINUX_LEDS_H_INCLUDED */