1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * One-shot LED Trigger |
4 | * |
5 | * Copyright 2012, Fabio Baltieri <fabio.baltieri@gmail.com> |
6 | * |
7 | * Based on ledtrig-timer.c by 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 | #include "../leds.h" |
18 | |
19 | #define DEFAULT_DELAY 100 |
20 | |
21 | struct oneshot_trig_data { |
22 | unsigned int invert; |
23 | }; |
24 | |
25 | static ssize_t led_shot(struct device *dev, |
26 | struct device_attribute *attr, const char *buf, size_t size) |
27 | { |
28 | struct led_classdev *led_cdev = led_trigger_get_led(dev); |
29 | struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev); |
30 | |
31 | led_blink_set_oneshot(led_cdev, |
32 | delay_on: &led_cdev->blink_delay_on, delay_off: &led_cdev->blink_delay_off, |
33 | invert: oneshot_data->invert); |
34 | |
35 | /* content is ignored */ |
36 | return size; |
37 | } |
38 | static ssize_t led_invert_show(struct device *dev, |
39 | struct device_attribute *attr, char *buf) |
40 | { |
41 | struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev); |
42 | |
43 | return sprintf(buf, fmt: "%u\n" , oneshot_data->invert); |
44 | } |
45 | |
46 | static ssize_t led_invert_store(struct device *dev, |
47 | struct device_attribute *attr, const char *buf, size_t size) |
48 | { |
49 | struct led_classdev *led_cdev = led_trigger_get_led(dev); |
50 | struct oneshot_trig_data *oneshot_data = led_trigger_get_drvdata(dev); |
51 | unsigned long state; |
52 | int ret; |
53 | |
54 | ret = kstrtoul(s: buf, base: 0, res: &state); |
55 | if (ret) |
56 | return ret; |
57 | |
58 | oneshot_data->invert = !!state; |
59 | |
60 | if (oneshot_data->invert) |
61 | led_set_brightness_nosleep(led_cdev, value: LED_FULL); |
62 | else |
63 | led_set_brightness_nosleep(led_cdev, value: LED_OFF); |
64 | |
65 | return size; |
66 | } |
67 | |
68 | static ssize_t led_delay_on_show(struct device *dev, |
69 | struct device_attribute *attr, char *buf) |
70 | { |
71 | struct led_classdev *led_cdev = led_trigger_get_led(dev); |
72 | |
73 | return sprintf(buf, fmt: "%lu\n" , led_cdev->blink_delay_on); |
74 | } |
75 | |
76 | static ssize_t led_delay_on_store(struct device *dev, |
77 | struct device_attribute *attr, const char *buf, size_t size) |
78 | { |
79 | struct led_classdev *led_cdev = led_trigger_get_led(dev); |
80 | unsigned long state; |
81 | int ret; |
82 | |
83 | ret = kstrtoul(s: buf, base: 0, res: &state); |
84 | if (ret) |
85 | return ret; |
86 | |
87 | led_cdev->blink_delay_on = state; |
88 | |
89 | return size; |
90 | } |
91 | |
92 | static ssize_t led_delay_off_show(struct device *dev, |
93 | struct device_attribute *attr, char *buf) |
94 | { |
95 | struct led_classdev *led_cdev = led_trigger_get_led(dev); |
96 | |
97 | return sprintf(buf, fmt: "%lu\n" , led_cdev->blink_delay_off); |
98 | } |
99 | |
100 | static ssize_t led_delay_off_store(struct device *dev, |
101 | struct device_attribute *attr, const char *buf, size_t size) |
102 | { |
103 | struct led_classdev *led_cdev = led_trigger_get_led(dev); |
104 | unsigned long state; |
105 | int ret; |
106 | |
107 | ret = kstrtoul(s: buf, base: 0, res: &state); |
108 | if (ret) |
109 | return ret; |
110 | |
111 | led_cdev->blink_delay_off = state; |
112 | |
113 | return size; |
114 | } |
115 | |
116 | static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store); |
117 | static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store); |
118 | static DEVICE_ATTR(invert, 0644, led_invert_show, led_invert_store); |
119 | static DEVICE_ATTR(shot, 0200, NULL, led_shot); |
120 | |
121 | static struct attribute *oneshot_trig_attrs[] = { |
122 | &dev_attr_delay_on.attr, |
123 | &dev_attr_delay_off.attr, |
124 | &dev_attr_invert.attr, |
125 | &dev_attr_shot.attr, |
126 | NULL |
127 | }; |
128 | ATTRIBUTE_GROUPS(oneshot_trig); |
129 | |
130 | static void pattern_init(struct led_classdev *led_cdev) |
131 | { |
132 | u32 *pattern; |
133 | unsigned int size = 0; |
134 | |
135 | pattern = led_get_default_pattern(led_cdev, size: &size); |
136 | if (!pattern) |
137 | goto out_default; |
138 | |
139 | if (size != 2) { |
140 | dev_warn(led_cdev->dev, |
141 | "Expected 2 but got %u values for delays pattern\n" , |
142 | size); |
143 | goto out_default; |
144 | } |
145 | |
146 | led_cdev->blink_delay_on = pattern[0]; |
147 | led_cdev->blink_delay_off = pattern[1]; |
148 | kfree(objp: pattern); |
149 | |
150 | return; |
151 | |
152 | out_default: |
153 | kfree(objp: pattern); |
154 | led_cdev->blink_delay_on = DEFAULT_DELAY; |
155 | led_cdev->blink_delay_off = DEFAULT_DELAY; |
156 | } |
157 | |
158 | static int oneshot_trig_activate(struct led_classdev *led_cdev) |
159 | { |
160 | struct oneshot_trig_data *oneshot_data; |
161 | |
162 | oneshot_data = kzalloc(size: sizeof(*oneshot_data), GFP_KERNEL); |
163 | if (!oneshot_data) |
164 | return -ENOMEM; |
165 | |
166 | led_set_trigger_data(led_cdev, trigger_data: oneshot_data); |
167 | |
168 | if (led_cdev->flags & LED_INIT_DEFAULT_TRIGGER) { |
169 | pattern_init(led_cdev); |
170 | /* |
171 | * Mark as initialized even on pattern_init() error because |
172 | * any consecutive call to it would produce the same error. |
173 | */ |
174 | led_cdev->flags &= ~LED_INIT_DEFAULT_TRIGGER; |
175 | } |
176 | |
177 | return 0; |
178 | } |
179 | |
180 | static void oneshot_trig_deactivate(struct led_classdev *led_cdev) |
181 | { |
182 | struct oneshot_trig_data *oneshot_data = led_get_trigger_data(led_cdev); |
183 | |
184 | kfree(objp: oneshot_data); |
185 | |
186 | /* Stop blinking */ |
187 | led_set_brightness(led_cdev, brightness: LED_OFF); |
188 | } |
189 | |
190 | static struct led_trigger oneshot_led_trigger = { |
191 | .name = "oneshot" , |
192 | .activate = oneshot_trig_activate, |
193 | .deactivate = oneshot_trig_deactivate, |
194 | .groups = oneshot_trig_groups, |
195 | }; |
196 | module_led_trigger(oneshot_led_trigger); |
197 | |
198 | MODULE_AUTHOR("Fabio Baltieri <fabio.baltieri@gmail.com>" ); |
199 | MODULE_DESCRIPTION("One-shot LED trigger" ); |
200 | MODULE_LICENSE("GPL v2" ); |
201 | |