linux/drivers/leds/led-class-multicolor.c
Dan Murphy 55d5d3b46b leds: multicolor: Introduce a multicolor class definition
Introduce a multicolor class that groups colored LEDs
within a LED node.

The multicolor class groups monochrome LEDs and allows controlling two
aspects of the final combined color: hue and lightness. The former is
controlled via the intensity file and the latter is controlled
via brightness file.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
[squashed leds: multicolor: Fix camel case in documentation in]
2020-07-22 14:41:29 +02:00

204 lines
5.0 KiB
C

// SPDX-License-Identifier: GPL-2.0
// LED Multicolor class interface
// Copyright (C) 2019-20 Texas Instruments Incorporated - http://www.ti.com/
// Author: Dan Murphy <dmurphy@ti.com>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/led-class-multicolor.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include "leds.h"
int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev,
enum led_brightness brightness)
{
struct led_classdev *led_cdev = &mcled_cdev->led_cdev;
int i;
for (i = 0; i < mcled_cdev->num_colors; i++)
mcled_cdev->subled_info[i].brightness = brightness *
mcled_cdev->subled_info[i].intensity /
led_cdev->max_brightness;
return 0;
}
EXPORT_SYMBOL_GPL(led_mc_calc_color_components);
static ssize_t multi_intensity_store(struct device *dev,
struct device_attribute *intensity_attr,
const char *buf, size_t size)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
int nrchars, offset = 0;
int intensity_value[LED_COLOR_ID_MAX];
int i;
ssize_t ret;
mutex_lock(&led_cdev->led_access);
for (i = 0; i < mcled_cdev->num_colors; i++) {
ret = sscanf(buf + offset, "%i%n",
&intensity_value[i], &nrchars);
if (ret != 1) {
ret = -EINVAL;
goto err_out;
}
offset += nrchars;
}
offset++;
if (offset < size) {
ret = -EINVAL;
goto err_out;
}
for (i = 0; i < mcled_cdev->num_colors; i++)
mcled_cdev->subled_info[i].intensity = intensity_value[i];
led_set_brightness(led_cdev, led_cdev->brightness);
ret = size;
err_out:
mutex_unlock(&led_cdev->led_access);
return ret;
}
static ssize_t multi_intensity_show(struct device *dev,
struct device_attribute *intensity_attr,
char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
int len = 0;
int i;
for (i = 0; i < mcled_cdev->num_colors; i++) {
len += sprintf(buf + len, "%d",
mcled_cdev->subled_info[i].intensity);
if (i < mcled_cdev->num_colors - 1)
len += sprintf(buf + len, " ");
}
buf[len++] = '\n';
return len;
}
static DEVICE_ATTR_RW(multi_intensity);
static ssize_t multi_index_show(struct device *dev,
struct device_attribute *multi_index_attr,
char *buf)
{
struct led_classdev *led_cdev = dev_get_drvdata(dev);
struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
int len = 0;
int index;
int i;
for (i = 0; i < mcled_cdev->num_colors; i++) {
index = mcled_cdev->subled_info[i].color_index;
len += sprintf(buf + len, "%s", led_colors[index]);
if (i < mcled_cdev->num_colors - 1)
len += sprintf(buf + len, " ");
}
buf[len++] = '\n';
return len;
}
static DEVICE_ATTR_RO(multi_index);
static struct attribute *led_multicolor_attrs[] = {
&dev_attr_multi_intensity.attr,
&dev_attr_multi_index.attr,
NULL,
};
ATTRIBUTE_GROUPS(led_multicolor);
int led_classdev_multicolor_register_ext(struct device *parent,
struct led_classdev_mc *mcled_cdev,
struct led_init_data *init_data)
{
struct led_classdev *led_cdev;
if (!mcled_cdev)
return -EINVAL;
if (mcled_cdev->num_colors <= 0)
return -EINVAL;
if (mcled_cdev->num_colors > LED_COLOR_ID_MAX)
return -EINVAL;
led_cdev = &mcled_cdev->led_cdev;
mcled_cdev->led_cdev.groups = led_multicolor_groups;
return led_classdev_register_ext(parent, led_cdev, init_data);
}
EXPORT_SYMBOL_GPL(led_classdev_multicolor_register_ext);
void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev)
{
if (!mcled_cdev)
return;
led_classdev_unregister(&mcled_cdev->led_cdev);
}
EXPORT_SYMBOL_GPL(led_classdev_multicolor_unregister);
static void devm_led_classdev_multicolor_release(struct device *dev, void *res)
{
led_classdev_multicolor_unregister(*(struct led_classdev_mc **)res);
}
int devm_led_classdev_multicolor_register_ext(struct device *parent,
struct led_classdev_mc *mcled_cdev,
struct led_init_data *init_data)
{
struct led_classdev_mc **dr;
int ret;
dr = devres_alloc(devm_led_classdev_multicolor_release,
sizeof(*dr), GFP_KERNEL);
if (!dr)
return -ENOMEM;
ret = led_classdev_multicolor_register_ext(parent, mcled_cdev,
init_data);
if (ret) {
devres_free(dr);
return ret;
}
*dr = mcled_cdev;
devres_add(parent, dr);
return 0;
}
EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_register_ext);
static int devm_led_classdev_multicolor_match(struct device *dev,
void *res, void *data)
{
struct led_classdev_mc **p = res;
if (WARN_ON(!p || !*p))
return 0;
return *p == data;
}
void devm_led_classdev_multicolor_unregister(struct device *dev,
struct led_classdev_mc *mcled_cdev)
{
WARN_ON(devres_release(dev,
devm_led_classdev_multicolor_release,
devm_led_classdev_multicolor_match, mcled_cdev));
}
EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_unregister);
MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
MODULE_DESCRIPTION("Multicolor LED class interface");
MODULE_LICENSE("GPL v2");