xref: /linux/drivers/leds/led-class-multicolor.c (revision e47a324d6f07c9ef252cfce1f14cfa5110cbed99)
1 // SPDX-License-Identifier: GPL-2.0
2 // LED Multicolor class interface
3 // Copyright (C) 2019-20 Texas Instruments Incorporated - http://www.ti.com/
4 // Author: Dan Murphy <dmurphy@ti.com>
5 
6 #include <linux/device.h>
7 #include <linux/init.h>
8 #include <linux/led-class-multicolor.h>
9 #include <linux/math.h>
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/uaccess.h>
13 
14 int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev,
15 				 enum led_brightness brightness)
16 {
17 	struct led_classdev *led_cdev = &mcled_cdev->led_cdev;
18 	int i;
19 
20 	for (i = 0; i < mcled_cdev->num_colors; i++)
21 		mcled_cdev->subled_info[i].brightness =
22 			DIV_ROUND_CLOSEST(brightness *
23 					  mcled_cdev->subled_info[i].intensity,
24 					  led_cdev->max_brightness);
25 
26 	return 0;
27 }
28 EXPORT_SYMBOL_GPL(led_mc_calc_color_components);
29 
30 static ssize_t multi_intensity_store(struct device *dev,
31 				struct device_attribute *intensity_attr,
32 				const char *buf, size_t size)
33 {
34 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
35 	struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
36 	int nrchars, offset = 0;
37 	int intensity_value[LED_COLOR_ID_MAX];
38 	int i;
39 	ssize_t ret;
40 
41 	mutex_lock(&led_cdev->led_access);
42 
43 	for (i = 0; i < mcled_cdev->num_colors; i++) {
44 		ret = sscanf(buf + offset, "%i%n",
45 			     &intensity_value[i], &nrchars);
46 		if (ret != 1) {
47 			ret = -EINVAL;
48 			goto err_out;
49 		}
50 		offset += nrchars;
51 	}
52 
53 	offset++;
54 	if (offset < size) {
55 		ret = -EINVAL;
56 		goto err_out;
57 	}
58 
59 	for (i = 0; i < mcled_cdev->num_colors; i++)
60 		mcled_cdev->subled_info[i].intensity = intensity_value[i];
61 
62 	if (!test_bit(LED_BLINK_SW, &led_cdev->work_flags))
63 		led_set_brightness(led_cdev, led_cdev->brightness);
64 	ret = size;
65 err_out:
66 	mutex_unlock(&led_cdev->led_access);
67 	return ret;
68 }
69 
70 static ssize_t multi_intensity_show(struct device *dev,
71 			      struct device_attribute *intensity_attr,
72 			      char *buf)
73 {
74 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
75 	struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
76 	int len = 0;
77 	int i;
78 
79 	for (i = 0; i < mcled_cdev->num_colors; i++) {
80 		len += sprintf(buf + len, "%d",
81 			       mcled_cdev->subled_info[i].intensity);
82 		if (i < mcled_cdev->num_colors - 1)
83 			len += sprintf(buf + len, " ");
84 	}
85 
86 	buf[len++] = '\n';
87 	return len;
88 }
89 static DEVICE_ATTR_RW(multi_intensity);
90 
91 static ssize_t multi_index_show(struct device *dev,
92 			      struct device_attribute *multi_index_attr,
93 			      char *buf)
94 {
95 	struct led_classdev *led_cdev = dev_get_drvdata(dev);
96 	struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
97 	int len = 0;
98 	int index;
99 	int i;
100 
101 	for (i = 0; i < mcled_cdev->num_colors; i++) {
102 		index = mcled_cdev->subled_info[i].color_index;
103 		len += sprintf(buf + len, "%s", led_get_color_name(index));
104 		if (i < mcled_cdev->num_colors - 1)
105 			len += sprintf(buf + len, " ");
106 	}
107 
108 	buf[len++] = '\n';
109 	return len;
110 }
111 static DEVICE_ATTR_RO(multi_index);
112 
113 static struct attribute *led_multicolor_attrs[] = {
114 	&dev_attr_multi_intensity.attr,
115 	&dev_attr_multi_index.attr,
116 	NULL,
117 };
118 ATTRIBUTE_GROUPS(led_multicolor);
119 
120 int led_classdev_multicolor_register_ext(struct device *parent,
121 				     struct led_classdev_mc *mcled_cdev,
122 				     struct led_init_data *init_data)
123 {
124 	struct led_classdev *led_cdev;
125 
126 	if (!mcled_cdev)
127 		return -EINVAL;
128 
129 	if (mcled_cdev->num_colors <= 0)
130 		return -EINVAL;
131 
132 	if (mcled_cdev->num_colors > LED_COLOR_ID_MAX)
133 		return -EINVAL;
134 
135 	led_cdev = &mcled_cdev->led_cdev;
136 	led_cdev->flags |= LED_MULTI_COLOR;
137 	mcled_cdev->led_cdev.groups = led_multicolor_groups;
138 
139 	return led_classdev_register_ext(parent, led_cdev, init_data);
140 }
141 EXPORT_SYMBOL_GPL(led_classdev_multicolor_register_ext);
142 
143 void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev)
144 {
145 	if (!mcled_cdev)
146 		return;
147 
148 	led_classdev_unregister(&mcled_cdev->led_cdev);
149 }
150 EXPORT_SYMBOL_GPL(led_classdev_multicolor_unregister);
151 
152 static void devm_led_classdev_multicolor_release(struct device *dev, void *res)
153 {
154 	led_classdev_multicolor_unregister(*(struct led_classdev_mc **)res);
155 }
156 
157 int devm_led_classdev_multicolor_register_ext(struct device *parent,
158 					     struct led_classdev_mc *mcled_cdev,
159 					     struct led_init_data *init_data)
160 {
161 	struct led_classdev_mc **dr;
162 	int ret;
163 
164 	dr = devres_alloc(devm_led_classdev_multicolor_release,
165 			  sizeof(*dr), GFP_KERNEL);
166 	if (!dr)
167 		return -ENOMEM;
168 
169 	ret = led_classdev_multicolor_register_ext(parent, mcled_cdev,
170 						   init_data);
171 	if (ret) {
172 		devres_free(dr);
173 		return ret;
174 	}
175 
176 	*dr = mcled_cdev;
177 	devres_add(parent, dr);
178 
179 	return 0;
180 }
181 EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_register_ext);
182 
183 static int devm_led_classdev_multicolor_match(struct device *dev,
184 					      void *res, void *data)
185 {
186 	struct led_classdev_mc **p = res;
187 
188 	if (WARN_ON(!p || !*p))
189 		return 0;
190 
191 	return *p == data;
192 }
193 
194 void devm_led_classdev_multicolor_unregister(struct device *dev,
195 					     struct led_classdev_mc *mcled_cdev)
196 {
197 	WARN_ON(devres_release(dev,
198 			       devm_led_classdev_multicolor_release,
199 			       devm_led_classdev_multicolor_match, mcled_cdev));
200 }
201 EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_unregister);
202 
203 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
204 MODULE_DESCRIPTION("Multicolor LED class interface");
205 MODULE_LICENSE("GPL v2");
206