1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * LED Kernel Timer Trigger
4 *
5 * Copyright 2005-2006 Openedhand Ltd.
6 *
7 * Author: Richard Purdie <rpurdie@openedhand.com>
8 */
9
10#include <linux/module.h>
11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/device.h>
14#include <linux/ctype.h>
15#include <linux/slab.h>
16#include <linux/leds.h>
17
18static ssize_t led_delay_on_show(struct device *dev,
19		struct device_attribute *attr, char *buf)
20{
21	struct led_classdev *led_cdev = led_trigger_get_led(dev);
22
23	return sprintf(buf, "%lu\n", led_cdev->blink_delay_on);
24}
25
26static ssize_t led_delay_on_store(struct device *dev,
27		struct device_attribute *attr, const char *buf, size_t size)
28{
29	struct led_classdev *led_cdev = led_trigger_get_led(dev);
30	unsigned long state;
31	ssize_t ret;
32
33	ret = kstrtoul(buf, 10, &state);
34	if (ret)
35		return ret;
36
37	led_blink_set(led_cdev, &state, &led_cdev->blink_delay_off);
38	led_cdev->blink_delay_on = state;
39
40	return size;
41}
42
43static ssize_t led_delay_off_show(struct device *dev,
44		struct device_attribute *attr, char *buf)
45{
46	struct led_classdev *led_cdev = led_trigger_get_led(dev);
47
48	return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
49}
50
51static ssize_t led_delay_off_store(struct device *dev,
52		struct device_attribute *attr, const char *buf, size_t size)
53{
54	struct led_classdev *led_cdev = led_trigger_get_led(dev);
55	unsigned long state;
56	ssize_t ret;
57
58	ret = kstrtoul(buf, 10, &state);
59	if (ret)
60		return ret;
61
62	led_blink_set(led_cdev, &led_cdev->blink_delay_on, &state);
63	led_cdev->blink_delay_off = state;
64
65	return size;
66}
67
68static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
69static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
70
71static struct attribute *timer_trig_attrs[] = {
72	&dev_attr_delay_on.attr,
73	&dev_attr_delay_off.attr,
74	NULL
75};
76ATTRIBUTE_GROUPS(timer_trig);
77
78static void pattern_init(struct led_classdev *led_cdev)
79{
80	u32 *pattern;
81	unsigned int size = 0;
82
83	pattern = led_get_default_pattern(led_cdev, &size);
84	if (!pattern)
85		return;
86
87	if (size != 2) {
88		dev_warn(led_cdev->dev,
89			 "Expected 2 but got %u values for delays pattern\n",
90			 size);
91		goto out;
92	}
93
94	led_cdev->blink_delay_on = pattern[0];
95	led_cdev->blink_delay_off = pattern[1];
96	/* led_blink_set() called by caller */
97
98out:
99	kfree(pattern);
100}
101
102static int timer_trig_activate(struct led_classdev *led_cdev)
103{
104	if (led_cdev->flags & LED_INIT_DEFAULT_TRIGGER) {
105		pattern_init(led_cdev);
106		/*
107		 * Mark as initialized even on pattern_init() error because
108		 * any consecutive call to it would produce the same error.
109		 */
110		led_cdev->flags &= ~LED_INIT_DEFAULT_TRIGGER;
111	}
112
113	/*
114	 * If "set brightness to 0" is pending in workqueue, we don't
115	 * want that to be reordered after blink_set()
116	 */
117	flush_work(&led_cdev->set_brightness_work);
118	led_blink_set(led_cdev, &led_cdev->blink_delay_on,
119		      &led_cdev->blink_delay_off);
120
121	return 0;
122}
123
124static void timer_trig_deactivate(struct led_classdev *led_cdev)
125{
126	/* Stop blinking */
127	led_set_brightness(led_cdev, LED_OFF);
128}
129
130static struct led_trigger timer_led_trigger = {
131	.name     = "timer",
132	.activate = timer_trig_activate,
133	.deactivate = timer_trig_deactivate,
134	.groups = timer_trig_groups,
135};
136module_led_trigger(timer_led_trigger);
137
138MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
139MODULE_DESCRIPTION("Timer LED trigger");
140MODULE_LICENSE("GPL v2");
141