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>
23 #include <uapi/linux/uleds.h>
26 static struct class *leds_class
;
28 static ssize_t
brightness_show(struct device
*dev
,
29 struct device_attribute
*attr
, char *buf
)
31 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
33 /* no lock needed for this */
34 led_update_brightness(led_cdev
);
36 return sprintf(buf
, "%u\n", led_cdev
->brightness
);
39 static ssize_t
brightness_store(struct device
*dev
,
40 struct device_attribute
*attr
, const char *buf
, size_t size
)
42 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
46 mutex_lock(&led_cdev
->led_access
);
48 if (led_sysfs_is_disabled(led_cdev
)) {
53 ret
= kstrtoul(buf
, 10, &state
);
58 led_trigger_remove(led_cdev
);
59 led_set_brightness(led_cdev
, state
);
60 flush_work(&led_cdev
->set_brightness_work
);
64 mutex_unlock(&led_cdev
->led_access
);
67 static DEVICE_ATTR_RW(brightness
);
69 static ssize_t
max_brightness_show(struct device
*dev
,
70 struct device_attribute
*attr
, char *buf
)
72 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
74 return sprintf(buf
, "%u\n", led_cdev
->max_brightness
);
76 static DEVICE_ATTR_RO(max_brightness
);
78 #ifdef CONFIG_LEDS_TRIGGERS
79 static DEVICE_ATTR(trigger
, 0644, led_trigger_show
, led_trigger_store
);
80 static struct attribute
*led_trigger_attrs
[] = {
81 &dev_attr_trigger
.attr
,
84 static const struct attribute_group led_trigger_group
= {
85 .attrs
= led_trigger_attrs
,
89 static struct attribute
*led_class_attrs
[] = {
90 &dev_attr_brightness
.attr
,
91 &dev_attr_max_brightness
.attr
,
95 static const struct attribute_group led_group
= {
96 .attrs
= led_class_attrs
,
99 static const struct attribute_group
*led_groups
[] = {
101 #ifdef CONFIG_LEDS_TRIGGERS
107 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
108 static ssize_t
brightness_hw_changed_show(struct device
*dev
,
109 struct device_attribute
*attr
, char *buf
)
111 struct led_classdev
*led_cdev
= dev_get_drvdata(dev
);
113 if (led_cdev
->brightness_hw_changed
== -1)
116 return sprintf(buf
, "%u\n", led_cdev
->brightness_hw_changed
);
119 static DEVICE_ATTR_RO(brightness_hw_changed
);
121 static int led_add_brightness_hw_changed(struct led_classdev
*led_cdev
)
123 struct device
*dev
= led_cdev
->dev
;
126 ret
= device_create_file(dev
, &dev_attr_brightness_hw_changed
);
128 dev_err(dev
, "Error creating brightness_hw_changed\n");
132 led_cdev
->brightness_hw_changed_kn
=
133 sysfs_get_dirent(dev
->kobj
.sd
, "brightness_hw_changed");
134 if (!led_cdev
->brightness_hw_changed_kn
) {
135 dev_err(dev
, "Error getting brightness_hw_changed kn\n");
136 device_remove_file(dev
, &dev_attr_brightness_hw_changed
);
143 static void led_remove_brightness_hw_changed(struct led_classdev
*led_cdev
)
145 sysfs_put(led_cdev
->brightness_hw_changed_kn
);
146 device_remove_file(led_cdev
->dev
, &dev_attr_brightness_hw_changed
);
149 void led_classdev_notify_brightness_hw_changed(struct led_classdev
*led_cdev
,
150 enum led_brightness brightness
)
152 if (WARN_ON(!led_cdev
->brightness_hw_changed_kn
))
155 led_cdev
->brightness_hw_changed
= brightness
;
156 sysfs_notify_dirent(led_cdev
->brightness_hw_changed_kn
);
158 EXPORT_SYMBOL_GPL(led_classdev_notify_brightness_hw_changed
);
160 static int led_add_brightness_hw_changed(struct led_classdev
*led_cdev
)
164 static void led_remove_brightness_hw_changed(struct led_classdev
*led_cdev
)
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_set_brightness_nopm(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_set_brightness_nopm(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 * of_led_classdev_register - register a new object of led_classdev class.
250 * @parent: parent of LED device
251 * @led_cdev: the led_classdev structure for this device.
252 * @np: DT node describing this LED
254 int of_led_classdev_register(struct device
*parent
, struct device_node
*np
,
255 struct led_classdev
*led_cdev
)
257 char name
[LED_MAX_NAME_SIZE
];
260 ret
= led_classdev_next_name(led_cdev
->name
, name
, sizeof(name
));
264 mutex_init(&led_cdev
->led_access
);
265 mutex_lock(&led_cdev
->led_access
);
266 led_cdev
->dev
= device_create_with_groups(leds_class
, parent
, 0,
267 led_cdev
, led_cdev
->groups
, "%s", name
);
268 if (IS_ERR(led_cdev
->dev
)) {
269 mutex_unlock(&led_cdev
->led_access
);
270 return PTR_ERR(led_cdev
->dev
);
272 led_cdev
->dev
->of_node
= np
;
275 dev_warn(parent
, "Led %s renamed to %s due to name collision",
276 led_cdev
->name
, dev_name(led_cdev
->dev
));
278 if (led_cdev
->flags
& LED_BRIGHT_HW_CHANGED
) {
279 ret
= led_add_brightness_hw_changed(led_cdev
);
281 device_unregister(led_cdev
->dev
);
282 mutex_unlock(&led_cdev
->led_access
);
287 led_cdev
->work_flags
= 0;
288 #ifdef CONFIG_LEDS_TRIGGERS
289 init_rwsem(&led_cdev
->trigger_lock
);
291 #ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
292 led_cdev
->brightness_hw_changed
= -1;
294 /* add to the list of leds */
295 down_write(&leds_list_lock
);
296 list_add_tail(&led_cdev
->node
, &leds_list
);
297 up_write(&leds_list_lock
);
299 if (!led_cdev
->max_brightness
)
300 led_cdev
->max_brightness
= LED_FULL
;
302 led_update_brightness(led_cdev
);
304 led_init_core(led_cdev
);
306 #ifdef CONFIG_LEDS_TRIGGERS
307 led_trigger_set_default(led_cdev
);
310 mutex_unlock(&led_cdev
->led_access
);
312 dev_dbg(parent
, "Registered led device: %s\n",
317 EXPORT_SYMBOL_GPL(of_led_classdev_register
);
320 * led_classdev_unregister - unregisters a object of led_properties class.
321 * @led_cdev: the led device to unregister
323 * Unregisters a previously registered via led_classdev_register object.
325 void led_classdev_unregister(struct led_classdev
*led_cdev
)
327 #ifdef CONFIG_LEDS_TRIGGERS
328 down_write(&led_cdev
->trigger_lock
);
329 if (led_cdev
->trigger
)
330 led_trigger_set(led_cdev
, NULL
);
331 up_write(&led_cdev
->trigger_lock
);
334 led_cdev
->flags
|= LED_UNREGISTERING
;
337 led_stop_software_blink(led_cdev
);
339 led_set_brightness(led_cdev
, LED_OFF
);
341 flush_work(&led_cdev
->set_brightness_work
);
343 if (led_cdev
->flags
& LED_BRIGHT_HW_CHANGED
)
344 led_remove_brightness_hw_changed(led_cdev
);
346 device_unregister(led_cdev
->dev
);
348 down_write(&leds_list_lock
);
349 list_del(&led_cdev
->node
);
350 up_write(&leds_list_lock
);
352 mutex_destroy(&led_cdev
->led_access
);
354 EXPORT_SYMBOL_GPL(led_classdev_unregister
);
356 static void devm_led_classdev_release(struct device
*dev
, void *res
)
358 led_classdev_unregister(*(struct led_classdev
**)res
);
362 * devm_of_led_classdev_register - resource managed led_classdev_register()
364 * @parent: parent of LED device
365 * @led_cdev: the led_classdev structure for this device.
367 int devm_of_led_classdev_register(struct device
*parent
,
368 struct device_node
*np
,
369 struct led_classdev
*led_cdev
)
371 struct led_classdev
**dr
;
374 dr
= devres_alloc(devm_led_classdev_release
, sizeof(*dr
), GFP_KERNEL
);
378 rc
= of_led_classdev_register(parent
, np
, led_cdev
);
385 devres_add(parent
, dr
);
389 EXPORT_SYMBOL_GPL(devm_of_led_classdev_register
);
391 static int devm_led_classdev_match(struct device
*dev
, void *res
, void *data
)
393 struct led_cdev
**p
= res
;
395 if (WARN_ON(!p
|| !*p
))
402 * devm_led_classdev_unregister() - resource managed led_classdev_unregister()
403 * @parent: The device to unregister.
404 * @led_cdev: the led_classdev structure for this device.
406 void devm_led_classdev_unregister(struct device
*dev
,
407 struct led_classdev
*led_cdev
)
409 WARN_ON(devres_release(dev
,
410 devm_led_classdev_release
,
411 devm_led_classdev_match
, led_cdev
));
413 EXPORT_SYMBOL_GPL(devm_led_classdev_unregister
);
415 static int __init
leds_init(void)
417 leds_class
= class_create(THIS_MODULE
, "leds");
418 if (IS_ERR(leds_class
))
419 return PTR_ERR(leds_class
);
420 leds_class
->pm
= &leds_class_dev_pm_ops
;
421 leds_class
->dev_groups
= led_groups
;
425 static void __exit
leds_exit(void)
427 class_destroy(leds_class
);
430 subsys_initcall(leds_init
);
431 module_exit(leds_exit
);
433 MODULE_AUTHOR("John Lenz, Richard Purdie");
434 MODULE_LICENSE("GPL");
435 MODULE_DESCRIPTION("LED Class Interface");