led-class-multicolor.c

  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
 14int 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}
 28EXPORT_SYMBOL_GPL(led_mc_calc_color_components);
 29
 30static 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;
 65err_out:
 66	mutex_unlock(&led_cdev->led_access);
 67	return ret;
 68}
 69
 70static 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}
 89static DEVICE_ATTR_RW(multi_intensity);
 90
 91static 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}
111static DEVICE_ATTR_RO(multi_index);
112
113static struct attribute *led_multicolor_attrs[] = {
114	&dev_attr_multi_intensity.attr,
115	&dev_attr_multi_index.attr,
116	NULL,
117};
118ATTRIBUTE_GROUPS(led_multicolor);
119
120int 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}
141EXPORT_SYMBOL_GPL(led_classdev_multicolor_register_ext);
142
143void 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}
150EXPORT_SYMBOL_GPL(led_classdev_multicolor_unregister);
151
152static void devm_led_classdev_multicolor_release(struct device *dev, void *res)
153{
154	led_classdev_multicolor_unregister(*(struct led_classdev_mc **)res);
155}
156
157int 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}
181EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_register_ext);
182
183static 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
194void 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}
201EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_unregister);
202
203MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
204MODULE_DESCRIPTION("Multicolor LED class interface");
205MODULE_LICENSE("GPL v2");