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135 lines · 3.1 KiB

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 <[email protected]>
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 led_blink_set(led_cdev, &led_cdev->blink_delay_on,
114 &led_cdev->blink_delay_off);
115
116 return 0;
117}
118
119static void timer_trig_deactivate(struct led_classdev *led_cdev)
120{
121 /* Stop blinking */
122 led_set_brightness(led_cdev, LED_OFF);
123}
124
125static struct led_trigger timer_led_trigger = {
126 .name = "timer",
127 .activate = timer_trig_activate,
128 .deactivate = timer_trig_deactivate,
129 .groups = timer_trig_groups,
130};
131module_led_trigger(timer_led_trigger);
132
133MODULE_AUTHOR("Richard Purdie <[email protected]>");
134MODULE_DESCRIPTION("Timer LED trigger");
135MODULE_LICENSE("GPL v2");