4 * Copyright 2005-2006 Openedhand Ltd.
6 * Author: Richard Purdie <rpurdie@openedhand.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
14 #include <linux/kernel.h>
15 #include <linux/leds.h>
16 #include <linux/list.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
20 #include <linux/rwsem.h>
21 #include <linux/slab.h>
24 DECLARE_RWSEM(leds_list_lock
);
25 EXPORT_SYMBOL_GPL(leds_list_lock
);
28 EXPORT_SYMBOL_GPL(leds_list
);
30 static int __led_set_brightness(struct led_classdev
*led_cdev
,
31 enum led_brightness value
)
33 if (!led_cdev
->brightness_set
)
36 led_cdev
->brightness_set(led_cdev
, value
);
41 static int __led_set_brightness_blocking(struct led_classdev
*led_cdev
,
42 enum led_brightness value
)
44 if (!led_cdev
->brightness_set_blocking
)
47 return led_cdev
->brightness_set_blocking(led_cdev
, value
);
50 static void led_timer_function(struct timer_list
*t
)
52 struct led_classdev
*led_cdev
= from_timer(led_cdev
, t
, blink_timer
);
53 unsigned long brightness
;
56 if (!led_cdev
->blink_delay_on
|| !led_cdev
->blink_delay_off
) {
57 led_set_brightness_nosleep(led_cdev
, LED_OFF
);
58 clear_bit(LED_BLINK_SW
, &led_cdev
->work_flags
);
62 if (test_and_clear_bit(LED_BLINK_ONESHOT_STOP
,
63 &led_cdev
->work_flags
)) {
64 clear_bit(LED_BLINK_SW
, &led_cdev
->work_flags
);
68 brightness
= led_get_brightness(led_cdev
);
70 /* Time to switch the LED on. */
71 if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE
,
72 &led_cdev
->work_flags
))
73 brightness
= led_cdev
->new_blink_brightness
;
75 brightness
= led_cdev
->blink_brightness
;
76 delay
= led_cdev
->blink_delay_on
;
78 /* Store the current brightness value to be able
79 * to restore it when the delay_off period is over.
81 led_cdev
->blink_brightness
= brightness
;
83 delay
= led_cdev
->blink_delay_off
;
86 led_set_brightness_nosleep(led_cdev
, brightness
);
88 /* Return in next iteration if led is in one-shot mode and we are in
89 * the final blink state so that the led is toggled each delay_on +
90 * delay_off milliseconds in worst case.
92 if (test_bit(LED_BLINK_ONESHOT
, &led_cdev
->work_flags
)) {
93 if (test_bit(LED_BLINK_INVERT
, &led_cdev
->work_flags
)) {
95 set_bit(LED_BLINK_ONESHOT_STOP
,
96 &led_cdev
->work_flags
);
99 set_bit(LED_BLINK_ONESHOT_STOP
,
100 &led_cdev
->work_flags
);
104 mod_timer(&led_cdev
->blink_timer
, jiffies
+ msecs_to_jiffies(delay
));
107 static void set_brightness_delayed(struct work_struct
*ws
)
109 struct led_classdev
*led_cdev
=
110 container_of(ws
, struct led_classdev
, set_brightness_work
);
113 if (test_and_clear_bit(LED_BLINK_DISABLE
, &led_cdev
->work_flags
)) {
114 led_cdev
->delayed_set_value
= LED_OFF
;
115 led_stop_software_blink(led_cdev
);
118 ret
= __led_set_brightness(led_cdev
, led_cdev
->delayed_set_value
);
119 if (ret
== -ENOTSUPP
)
120 ret
= __led_set_brightness_blocking(led_cdev
,
121 led_cdev
->delayed_set_value
);
123 /* LED HW might have been unplugged, therefore don't warn */
124 !(ret
== -ENODEV
&& (led_cdev
->flags
& LED_UNREGISTERING
) &&
125 (led_cdev
->flags
& LED_HW_PLUGGABLE
)))
126 dev_err(led_cdev
->dev
,
127 "Setting an LED's brightness failed (%d)\n", ret
);
130 static void led_set_software_blink(struct led_classdev
*led_cdev
,
131 unsigned long delay_on
,
132 unsigned long delay_off
)
134 int current_brightness
;
136 current_brightness
= led_get_brightness(led_cdev
);
137 if (current_brightness
)
138 led_cdev
->blink_brightness
= current_brightness
;
139 if (!led_cdev
->blink_brightness
)
140 led_cdev
->blink_brightness
= led_cdev
->max_brightness
;
142 led_cdev
->blink_delay_on
= delay_on
;
143 led_cdev
->blink_delay_off
= delay_off
;
145 /* never on - just set to off */
147 led_set_brightness_nosleep(led_cdev
, LED_OFF
);
151 /* never off - just set to brightness */
153 led_set_brightness_nosleep(led_cdev
,
154 led_cdev
->blink_brightness
);
158 set_bit(LED_BLINK_SW
, &led_cdev
->work_flags
);
159 mod_timer(&led_cdev
->blink_timer
, jiffies
+ 1);
163 static void led_blink_setup(struct led_classdev
*led_cdev
,
164 unsigned long *delay_on
,
165 unsigned long *delay_off
)
167 if (!test_bit(LED_BLINK_ONESHOT
, &led_cdev
->work_flags
) &&
168 led_cdev
->blink_set
&&
169 !led_cdev
->blink_set(led_cdev
, delay_on
, delay_off
))
172 /* blink with 1 Hz as default if nothing specified */
173 if (!*delay_on
&& !*delay_off
)
174 *delay_on
= *delay_off
= 500;
176 led_set_software_blink(led_cdev
, *delay_on
, *delay_off
);
179 void led_init_core(struct led_classdev
*led_cdev
)
181 INIT_WORK(&led_cdev
->set_brightness_work
, set_brightness_delayed
);
183 timer_setup(&led_cdev
->blink_timer
, led_timer_function
, 0);
185 EXPORT_SYMBOL_GPL(led_init_core
);
187 void led_blink_set(struct led_classdev
*led_cdev
,
188 unsigned long *delay_on
,
189 unsigned long *delay_off
)
191 del_timer_sync(&led_cdev
->blink_timer
);
193 clear_bit(LED_BLINK_SW
, &led_cdev
->work_flags
);
194 clear_bit(LED_BLINK_ONESHOT
, &led_cdev
->work_flags
);
195 clear_bit(LED_BLINK_ONESHOT_STOP
, &led_cdev
->work_flags
);
197 led_blink_setup(led_cdev
, delay_on
, delay_off
);
199 EXPORT_SYMBOL_GPL(led_blink_set
);
201 void led_blink_set_oneshot(struct led_classdev
*led_cdev
,
202 unsigned long *delay_on
,
203 unsigned long *delay_off
,
206 if (test_bit(LED_BLINK_ONESHOT
, &led_cdev
->work_flags
) &&
207 timer_pending(&led_cdev
->blink_timer
))
210 set_bit(LED_BLINK_ONESHOT
, &led_cdev
->work_flags
);
211 clear_bit(LED_BLINK_ONESHOT_STOP
, &led_cdev
->work_flags
);
214 set_bit(LED_BLINK_INVERT
, &led_cdev
->work_flags
);
216 clear_bit(LED_BLINK_INVERT
, &led_cdev
->work_flags
);
218 led_blink_setup(led_cdev
, delay_on
, delay_off
);
220 EXPORT_SYMBOL_GPL(led_blink_set_oneshot
);
222 void led_stop_software_blink(struct led_classdev
*led_cdev
)
224 del_timer_sync(&led_cdev
->blink_timer
);
225 led_cdev
->blink_delay_on
= 0;
226 led_cdev
->blink_delay_off
= 0;
227 clear_bit(LED_BLINK_SW
, &led_cdev
->work_flags
);
229 EXPORT_SYMBOL_GPL(led_stop_software_blink
);
231 void led_set_brightness(struct led_classdev
*led_cdev
,
232 enum led_brightness brightness
)
235 * If software blink is active, delay brightness setting
236 * until the next timer tick.
238 if (test_bit(LED_BLINK_SW
, &led_cdev
->work_flags
)) {
240 * If we need to disable soft blinking delegate this to the
241 * work queue task to avoid problems in case we are called
242 * from hard irq context.
244 if (brightness
== LED_OFF
) {
245 set_bit(LED_BLINK_DISABLE
, &led_cdev
->work_flags
);
246 schedule_work(&led_cdev
->set_brightness_work
);
248 set_bit(LED_BLINK_BRIGHTNESS_CHANGE
,
249 &led_cdev
->work_flags
);
250 led_cdev
->new_blink_brightness
= brightness
;
255 led_set_brightness_nosleep(led_cdev
, brightness
);
257 EXPORT_SYMBOL_GPL(led_set_brightness
);
259 void led_set_brightness_nopm(struct led_classdev
*led_cdev
,
260 enum led_brightness value
)
262 /* Use brightness_set op if available, it is guaranteed not to sleep */
263 if (!__led_set_brightness(led_cdev
, value
))
266 /* If brightness setting can sleep, delegate it to a work queue task */
267 led_cdev
->delayed_set_value
= value
;
268 schedule_work(&led_cdev
->set_brightness_work
);
270 EXPORT_SYMBOL_GPL(led_set_brightness_nopm
);
272 void led_set_brightness_nosleep(struct led_classdev
*led_cdev
,
273 enum led_brightness value
)
275 led_cdev
->brightness
= min(value
, led_cdev
->max_brightness
);
277 if (led_cdev
->flags
& LED_SUSPENDED
)
280 led_set_brightness_nopm(led_cdev
, led_cdev
->brightness
);
282 EXPORT_SYMBOL_GPL(led_set_brightness_nosleep
);
284 int led_set_brightness_sync(struct led_classdev
*led_cdev
,
285 enum led_brightness value
)
287 if (led_cdev
->blink_delay_on
|| led_cdev
->blink_delay_off
)
290 led_cdev
->brightness
= min(value
, led_cdev
->max_brightness
);
292 if (led_cdev
->flags
& LED_SUSPENDED
)
295 return __led_set_brightness_blocking(led_cdev
, led_cdev
->brightness
);
297 EXPORT_SYMBOL_GPL(led_set_brightness_sync
);
299 int led_update_brightness(struct led_classdev
*led_cdev
)
303 if (led_cdev
->brightness_get
) {
304 ret
= led_cdev
->brightness_get(led_cdev
);
306 led_cdev
->brightness
= ret
;
313 EXPORT_SYMBOL_GPL(led_update_brightness
);
315 u32
*led_get_default_pattern(struct led_classdev
*led_cdev
, unsigned int *size
)
317 struct device_node
*np
= dev_of_node(led_cdev
->dev
);
324 count
= of_property_count_u32_elems(np
, "led-pattern");
328 pattern
= kcalloc(count
, sizeof(*pattern
), GFP_KERNEL
);
332 if (of_property_read_u32_array(np
, "led-pattern", pattern
, count
)) {
341 EXPORT_SYMBOL_GPL(led_get_default_pattern
);
343 /* Caller must ensure led_cdev->led_access held */
344 void led_sysfs_disable(struct led_classdev
*led_cdev
)
346 lockdep_assert_held(&led_cdev
->led_access
);
348 led_cdev
->flags
|= LED_SYSFS_DISABLE
;
350 EXPORT_SYMBOL_GPL(led_sysfs_disable
);
352 /* Caller must ensure led_cdev->led_access held */
353 void led_sysfs_enable(struct led_classdev
*led_cdev
)
355 lockdep_assert_held(&led_cdev
->led_access
);
357 led_cdev
->flags
&= ~LED_SYSFS_DISABLE
;
359 EXPORT_SYMBOL_GPL(led_sysfs_enable
);