4 * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
5 * Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
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.
12 #include <linux/ctype.h>
13 #include <linux/device.h>
14 #include <linux/err.h>
15 #include <linux/init.h>
16 #include <linux/kernel.h>
17 #include <linux/leds.h>
18 #include <linux/list.h>
19 #include <linux/module.h>
20 #include <linux/slab.h>
21 #include <linux/spinlock.h>
22 #include <linux/timer.h>
25 static struct class *leds_class
;
27 static ssize_t
brightness_show(struct device
*dev
,
28 struct device_attribute
*attr
, char *buf
)
30 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
32 /* no lock needed for this */
33 led_update_brightness(led_cdev
);
35 return sprintf(buf
, "%u\n", led_cdev
->brightness
);
38 static ssize_t
brightness_store(struct device
*dev
,
39 struct device_attribute
*attr
, const char *buf
, size_t size
)
41 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
45 mutex_lock(&led_cdev
->led_access
);
47 if (led_sysfs_is_disabled(led_cdev
)) {
52 ret
= kstrtoul(buf
, 10, &state
);
57 led_trigger_remove(led_cdev
);
58 led_set_brightness(led_cdev
, state
);
62 mutex_unlock(&led_cdev
->led_access
);
65 static DEVICE_ATTR_RW(brightness
);
67 static ssize_t
max_brightness_show(struct device
*dev
,
68 struct device_attribute
*attr
, char *buf
)
70 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
72 return sprintf(buf
, "%u\n", led_cdev
->max_brightness
);
74 static DEVICE_ATTR_RO(max_brightness
);
76 #ifdef CONFIG_LEDS_TRIGGERS
77 static DEVICE_ATTR(trigger
, 0644, led_trigger_show
, led_trigger_store
);
78 static struct attribute
*led_trigger_attrs
[] = {
79 &dev_attr_trigger
.attr
,
82 static const struct attribute_group led_trigger_group
= {
83 .attrs
= led_trigger_attrs
,
87 static struct attribute
*led_class_attrs
[] = {
88 &dev_attr_brightness
.attr
,
89 &dev_attr_max_brightness
.attr
,
93 static const struct attribute_group led_group
= {
94 .attrs
= led_class_attrs
,
97 static const struct attribute_group
*led_groups
[] = {
99 #ifdef CONFIG_LEDS_TRIGGERS
105 static void led_timer_function(unsigned long data
)
107 struct led_classdev
*led_cdev
= (void *)data
;
108 unsigned long brightness
;
111 if (!led_cdev
->blink_delay_on
|| !led_cdev
->blink_delay_off
) {
112 led_set_brightness_async(led_cdev
, LED_OFF
);
116 if (led_cdev
->flags
& LED_BLINK_ONESHOT_STOP
) {
117 led_cdev
->flags
&= ~LED_BLINK_ONESHOT_STOP
;
121 brightness
= led_get_brightness(led_cdev
);
123 /* Time to switch the LED on. */
124 if (led_cdev
->delayed_set_value
) {
125 led_cdev
->blink_brightness
=
126 led_cdev
->delayed_set_value
;
127 led_cdev
->delayed_set_value
= 0;
129 brightness
= led_cdev
->blink_brightness
;
130 delay
= led_cdev
->blink_delay_on
;
132 /* Store the current brightness value to be able
133 * to restore it when the delay_off period is over.
135 led_cdev
->blink_brightness
= brightness
;
136 brightness
= LED_OFF
;
137 delay
= led_cdev
->blink_delay_off
;
140 led_set_brightness_async(led_cdev
, brightness
);
142 /* Return in next iteration if led is in one-shot mode and we are in
143 * the final blink state so that the led is toggled each delay_on +
144 * delay_off milliseconds in worst case.
146 if (led_cdev
->flags
& LED_BLINK_ONESHOT
) {
147 if (led_cdev
->flags
& LED_BLINK_INVERT
) {
149 led_cdev
->flags
|= LED_BLINK_ONESHOT_STOP
;
152 led_cdev
->flags
|= LED_BLINK_ONESHOT_STOP
;
156 mod_timer(&led_cdev
->blink_timer
, jiffies
+ msecs_to_jiffies(delay
));
159 static void set_brightness_delayed(struct work_struct
*ws
)
161 struct led_classdev
*led_cdev
=
162 container_of(ws
, struct led_classdev
, set_brightness_work
);
164 led_stop_software_blink(led_cdev
);
166 led_set_brightness_async(led_cdev
, led_cdev
->delayed_set_value
);
170 * led_classdev_suspend - suspend an led_classdev.
171 * @led_cdev: the led_classdev to suspend.
173 void led_classdev_suspend(struct led_classdev
*led_cdev
)
175 led_cdev
->flags
|= LED_SUSPENDED
;
176 led_cdev
->brightness_set(led_cdev
, 0);
178 EXPORT_SYMBOL_GPL(led_classdev_suspend
);
181 * led_classdev_resume - resume an led_classdev.
182 * @led_cdev: the led_classdev to resume.
184 void led_classdev_resume(struct led_classdev
*led_cdev
)
186 led_cdev
->brightness_set(led_cdev
, led_cdev
->brightness
);
188 if (led_cdev
->flash_resume
)
189 led_cdev
->flash_resume(led_cdev
);
191 led_cdev
->flags
&= ~LED_SUSPENDED
;
193 EXPORT_SYMBOL_GPL(led_classdev_resume
);
195 #ifdef CONFIG_PM_SLEEP
196 static int led_suspend(struct device
*dev
)
198 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
200 if (led_cdev
->flags
& LED_CORE_SUSPENDRESUME
)
201 led_classdev_suspend(led_cdev
);
206 static int led_resume(struct device
*dev
)
208 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
210 if (led_cdev
->flags
& LED_CORE_SUSPENDRESUME
)
211 led_classdev_resume(led_cdev
);
217 static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops
, led_suspend
, led_resume
);
219 static int match_name(struct device
*dev
, const void *data
)
223 return !strcmp(dev_name(dev
), (char *)data
);
226 static int led_classdev_next_name(const char *init_name
, char *name
,
233 strlcpy(name
, init_name
, len
);
235 while ((ret
< len
) &&
236 (dev
= class_find_device(leds_class
, NULL
, name
, match_name
))) {
238 ret
= snprintf(name
, len
, "%s_%u", init_name
, ++i
);
248 * led_classdev_register - register a new object of led_classdev class.
249 * @parent: The device to register.
250 * @led_cdev: the led_classdev structure for this device.
252 int led_classdev_register(struct device
*parent
, struct led_classdev
*led_cdev
)
257 ret
= led_classdev_next_name(led_cdev
->name
, name
, sizeof(name
));
261 led_cdev
->dev
= device_create_with_groups(leds_class
, parent
, 0,
262 led_cdev
, led_cdev
->groups
, "%s", name
);
263 if (IS_ERR(led_cdev
->dev
))
264 return PTR_ERR(led_cdev
->dev
);
267 dev_warn(parent
, "Led %s renamed to %s due to name collision",
268 led_cdev
->name
, dev_name(led_cdev
->dev
));
270 #ifdef CONFIG_LEDS_TRIGGERS
271 init_rwsem(&led_cdev
->trigger_lock
);
273 mutex_init(&led_cdev
->led_access
);
274 /* add to the list of leds */
275 down_write(&leds_list_lock
);
276 list_add_tail(&led_cdev
->node
, &leds_list
);
277 up_write(&leds_list_lock
);
279 if (!led_cdev
->max_brightness
)
280 led_cdev
->max_brightness
= LED_FULL
;
282 led_cdev
->flags
|= SET_BRIGHTNESS_ASYNC
;
284 led_update_brightness(led_cdev
);
286 INIT_WORK(&led_cdev
->set_brightness_work
, set_brightness_delayed
);
288 setup_timer(&led_cdev
->blink_timer
, led_timer_function
,
289 (unsigned long)led_cdev
);
291 #ifdef CONFIG_LEDS_TRIGGERS
292 led_trigger_set_default(led_cdev
);
295 dev_dbg(parent
, "Registered led device: %s\n",
300 EXPORT_SYMBOL_GPL(led_classdev_register
);
303 * led_classdev_unregister - unregisters a object of led_properties class.
304 * @led_cdev: the led device to unregister
306 * Unregisters a previously registered via led_classdev_register object.
308 void led_classdev_unregister(struct led_classdev
*led_cdev
)
310 #ifdef CONFIG_LEDS_TRIGGERS
311 down_write(&led_cdev
->trigger_lock
);
312 if (led_cdev
->trigger
)
313 led_trigger_set(led_cdev
, NULL
);
314 up_write(&led_cdev
->trigger_lock
);
317 cancel_work_sync(&led_cdev
->set_brightness_work
);
320 led_stop_software_blink(led_cdev
);
321 led_set_brightness(led_cdev
, LED_OFF
);
323 device_unregister(led_cdev
->dev
);
325 down_write(&leds_list_lock
);
326 list_del(&led_cdev
->node
);
327 up_write(&leds_list_lock
);
329 mutex_destroy(&led_cdev
->led_access
);
331 EXPORT_SYMBOL_GPL(led_classdev_unregister
);
333 static void devm_led_classdev_release(struct device
*dev
, void *res
)
335 led_classdev_unregister(*(struct led_classdev
**)res
);
339 * devm_led_classdev_register - resource managed led_classdev_register()
340 * @parent: The device to register.
341 * @led_cdev: the led_classdev structure for this device.
343 int devm_led_classdev_register(struct device
*parent
,
344 struct led_classdev
*led_cdev
)
346 struct led_classdev
**dr
;
349 dr
= devres_alloc(devm_led_classdev_release
, sizeof(*dr
), GFP_KERNEL
);
353 rc
= led_classdev_register(parent
, led_cdev
);
360 devres_add(parent
, dr
);
364 EXPORT_SYMBOL_GPL(devm_led_classdev_register
);
366 static int devm_led_classdev_match(struct device
*dev
, void *res
, void *data
)
368 struct led_cdev
**p
= res
;
370 if (WARN_ON(!p
|| !*p
))
377 * devm_led_classdev_unregister() - resource managed led_classdev_unregister()
378 * @parent: The device to unregister.
379 * @led_cdev: the led_classdev structure for this device.
381 void devm_led_classdev_unregister(struct device
*dev
,
382 struct led_classdev
*led_cdev
)
384 WARN_ON(devres_release(dev
,
385 devm_led_classdev_release
,
386 devm_led_classdev_match
, led_cdev
));
388 EXPORT_SYMBOL_GPL(devm_led_classdev_unregister
);
390 static int __init
leds_init(void)
392 leds_class
= class_create(THIS_MODULE
, "leds");
393 if (IS_ERR(leds_class
))
394 return PTR_ERR(leds_class
);
395 leds_class
->pm
= &leds_class_dev_pm_ops
;
396 leds_class
->dev_groups
= led_groups
;
400 static void __exit
leds_exit(void)
402 class_destroy(leds_class
);
405 subsys_initcall(leds_init
);
406 module_exit(leds_exit
);
408 MODULE_AUTHOR("John Lenz, Richard Purdie");
409 MODULE_LICENSE("GPL");
410 MODULE_DESCRIPTION("LED Class Interface");