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 | |
18 | static 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, fmt: "%lu\n" , led_cdev->blink_delay_on); |
24 | } |
25 | |
26 | static 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(s: buf, base: 10, res: &state); |
34 | if (ret) |
35 | return ret; |
36 | |
37 | led_blink_set(led_cdev, delay_on: &state, delay_off: &led_cdev->blink_delay_off); |
38 | led_cdev->blink_delay_on = state; |
39 | |
40 | return size; |
41 | } |
42 | |
43 | static 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, fmt: "%lu\n" , led_cdev->blink_delay_off); |
49 | } |
50 | |
51 | static 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(s: buf, base: 10, res: &state); |
59 | if (ret) |
60 | return ret; |
61 | |
62 | led_blink_set(led_cdev, delay_on: &led_cdev->blink_delay_on, delay_off: &state); |
63 | led_cdev->blink_delay_off = state; |
64 | |
65 | return size; |
66 | } |
67 | |
68 | static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store); |
69 | static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store); |
70 | |
71 | static struct attribute *timer_trig_attrs[] = { |
72 | &dev_attr_delay_on.attr, |
73 | &dev_attr_delay_off.attr, |
74 | NULL |
75 | }; |
76 | ATTRIBUTE_GROUPS(timer_trig); |
77 | |
78 | static 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: &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 | |
98 | out: |
99 | kfree(objp: pattern); |
100 | } |
101 | |
102 | static 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(work: &led_cdev->set_brightness_work); |
118 | led_blink_set(led_cdev, delay_on: &led_cdev->blink_delay_on, |
119 | delay_off: &led_cdev->blink_delay_off); |
120 | |
121 | return 0; |
122 | } |
123 | |
124 | static void timer_trig_deactivate(struct led_classdev *led_cdev) |
125 | { |
126 | /* Stop blinking */ |
127 | led_set_brightness(led_cdev, brightness: LED_OFF); |
128 | } |
129 | |
130 | static 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 | }; |
136 | module_led_trigger(timer_led_trigger); |
137 | |
138 | MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>" ); |
139 | MODULE_DESCRIPTION("Timer LED trigger" ); |
140 | MODULE_LICENSE("GPL v2" ); |
141 | |