Introduce a multicolor class that groups colored LEDs within a LED node. The multi color class groups monochrome LEDs and allows controlling two aspects of the final combined color: hue and lightness. The former is controlled via <color>_intensity files and the latter is controlled via brightness file. Signed-off-by: Dan Murphy <dmurphy@xxxxxx> --- drivers/leds/Kconfig | 10 ++ drivers/leds/Makefile | 1 + drivers/leds/led-class-multicolor.c | 220 +++++++++++++++++++++++++++ include/linux/led-class-multicolor.h | 74 +++++++++ 4 files changed, 305 insertions(+) create mode 100644 drivers/leds/led-class-multicolor.c create mode 100644 include/linux/led-class-multicolor.h diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 6e7703fd03d0..cfb1ebb6517f 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -30,6 +30,16 @@ config LEDS_CLASS_FLASH for the flash related features of a LED device. It can be built as a module. +config LEDS_CLASS_MULTI_COLOR + tristate "LED Mulit Color LED Class Support" + depends on LEDS_CLASS + help + This option enables the multicolor LED sysfs class in /sys/class/leds. + It wraps LED class and adds multicolor LED specific sysfs attributes + and kernel internal API to it. You'll need this to provide support + for multicolor LEDs that are grouped together. This class is not + intended for single color LEDs. It can be built as a module. + config LEDS_BRIGHTNESS_HW_CHANGED bool "LED Class brightness_hw_changed attribute support" depends on LEDS_CLASS diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index 2da39e896ce8..841038cfe35b 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_NEW_LEDS) += led-core.o obj-$(CONFIG_LEDS_CLASS) += led-class.o obj-$(CONFIG_LEDS_CLASS_FLASH) += led-class-flash.o +obj-$(CONFIG_LEDS_CLASS_MULTI_COLOR) += led-class-multicolor.o obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o # LED Platform Drivers diff --git a/drivers/leds/led-class-multicolor.c b/drivers/leds/led-class-multicolor.c new file mode 100644 index 000000000000..25371bd9a860 --- /dev/null +++ b/drivers/leds/led-class-multicolor.c @@ -0,0 +1,220 @@ +// SPDX-License-Identifier: GPL-2.0 +// LED Multi Color class interface +// Copyright (C) 2019 Texas Instruments Incorporated - http://www.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" + +#define INTENSITY_NAME "_intensity" +#define MAX_INTENSITY_NAME "_max_intensity" + +void led_mc_calc_brightness(struct led_classdev_mc *mcled_cdev, + enum led_brightness brightness, + int brightness_val[]) +{ + struct led_mc_color_entry *priv; + int i = 0; + + list_for_each_entry(priv, &mcled_cdev->color_list, list) { + brightness_val[i] = brightness * + priv->intensity / priv->max_intensity; + i++; + } +} +EXPORT_SYMBOL_GPL(led_mc_calc_brightness); + +static ssize_t intensity_store(struct device *dev, + struct device_attribute *intensity_attr, + const char *buf, size_t size) +{ + struct led_mc_color_entry *priv = container_of(intensity_attr, + struct led_mc_color_entry, + intensity_attr); + struct led_classdev *led_cdev = priv->mcled_cdev->led_cdev; + unsigned long value; + ssize_t ret; + + mutex_lock(&led_cdev->led_access); + + ret = kstrtoul(buf, 10, &value); + if (ret) + goto unlock; + + if (value > priv->max_intensity) { + ret = -EINVAL; + goto unlock; + } + + priv->intensity = value; + ret = size; + +unlock: + mutex_unlock(&led_cdev->led_access); + return ret; +} + +static ssize_t intensity_show(struct device *dev, + struct device_attribute *intensity_attr, + char *buf) +{ + struct led_mc_color_entry *priv = container_of(intensity_attr, + struct led_mc_color_entry, + intensity_attr); + + return sprintf(buf, "%d\n", priv->intensity); +} + +static ssize_t max_intensity_show(struct device *dev, + struct device_attribute *max_intensity_attr, + char *buf) +{ + struct led_mc_color_entry *priv = container_of(max_intensity_attr, + struct led_mc_color_entry, + max_intensity_attr); + + return sprintf(buf, "%d\n", priv->max_intensity); +} + +static struct attribute *led_color_attrs[] = { + NULL, +}; + +static struct attribute_group led_color_group = { + .name = "colors", + .attrs = led_color_attrs, +}; + +static int led_multicolor_init_color(struct led_classdev_mc *mcled_cdev, + int color_id, int color_index) +{ + struct led_classdev *led_cdev = mcled_cdev->led_cdev; + struct led_mc_color_entry *mc_priv; + char *intensity_file_name; + char *max_intensity_file_name; + size_t len; + int ret; + + mc_priv = devm_kzalloc(led_cdev->dev, sizeof(*mc_priv), GFP_KERNEL); + if (!mc_priv) + return -ENOMEM; + + mc_priv->led_color_id = color_id; + mc_priv->mcled_cdev = mcled_cdev; + + sysfs_attr_init(&mc_priv->intensity_attr.attr); + len = strlen(led_colors[color_id]) + strlen(INTENSITY_NAME) + 1; + intensity_file_name = kzalloc(len, GFP_KERNEL); + if (!intensity_file_name) + return -ENOMEM; + + snprintf(intensity_file_name, len, "%s%s", + led_colors[color_id], INTENSITY_NAME); + mc_priv->intensity_attr.attr.name = intensity_file_name; + mc_priv->intensity_attr.attr.mode = 644; + mc_priv->intensity_attr.store = intensity_store; + mc_priv->intensity_attr.show = intensity_show; + ret = sysfs_add_file_to_group(&led_cdev->dev->kobj, + &mc_priv->intensity_attr.attr, + led_color_group.name); + if (ret) + goto intensity_err_out; + + sysfs_attr_init(&mc_priv->max_intensity_attr.attr); + len = strlen(led_colors[color_id]) + strlen(MAX_INTENSITY_NAME) + 1; + max_intensity_file_name = kzalloc(len, GFP_KERNEL); + if (!max_intensity_file_name) { + ret = -ENOMEM; + goto intensity_err_out; + } + + snprintf(max_intensity_file_name, len, "%s%s", + led_colors[color_id], MAX_INTENSITY_NAME); + mc_priv->max_intensity_attr.attr.name = max_intensity_file_name; + mc_priv->max_intensity_attr.attr.mode = 444; + mc_priv->max_intensity_attr.show = max_intensity_show; + ret = sysfs_add_file_to_group(&led_cdev->dev->kobj, + &mc_priv->max_intensity_attr.attr, + led_color_group.name); + if (ret) + goto max_intensity_err_out; + + mc_priv->max_intensity = LED_FULL; + list_add_tail(&mc_priv->list, &mcled_cdev->color_list); + +max_intensity_err_out: + kfree(max_intensity_file_name); +intensity_err_out: + kfree(intensity_file_name); + return ret; +} + +static int led_multicolor_init_color_dir(struct led_classdev_mc *mcled_cdev) +{ + struct led_classdev *led_cdev = mcled_cdev->led_cdev; + int ret; + int i, color_index = 0; + + ret = sysfs_create_group(&led_cdev->dev->kobj, &led_color_group); + if (ret) + return ret; + + for (i = 0; i < LED_COLOR_ID_MAX; i++) { + if (test_bit(i, &mcled_cdev->available_colors)) { + ret = led_multicolor_init_color(mcled_cdev, i, + color_index); + if (ret) + break; + + color_index++; + } + } + + return ret; +} + +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; + int ret; + + if (!mcled_cdev) + return -EINVAL; + + led_cdev = mcled_cdev->led_cdev; + INIT_LIST_HEAD(&mcled_cdev->color_list); + + /* Register led class device */ + ret = led_classdev_register_ext(parent, led_cdev, init_data); + if (ret) + return ret; + + return led_multicolor_init_color_dir(mcled_cdev); +} +EXPORT_SYMBOL_GPL(led_classdev_multicolor_register_ext); + +void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev) +{ + struct led_mc_color_entry *priv, *next; + + if (!mcled_cdev) + return; + + list_for_each_entry_safe(priv, next, &mcled_cdev->color_list, list) + list_del(&priv->list); + + sysfs_remove_group(&mcled_cdev->led_cdev->dev->kobj, &led_color_group); + led_classdev_unregister(mcled_cdev->led_cdev); +} +EXPORT_SYMBOL_GPL(led_classdev_multicolor_unregister); + +MODULE_AUTHOR("Dan Murphy <dmurphy@xxxxxx>"); +MODULE_DESCRIPTION("Multi Color LED class interface"); +MODULE_LICENSE("GPL v2"); diff --git a/include/linux/led-class-multicolor.h b/include/linux/led-class-multicolor.h new file mode 100644 index 000000000000..280ba5a614b4 --- /dev/null +++ b/include/linux/led-class-multicolor.h @@ -0,0 +1,74 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* LED Multicolor class interface + * Copyright (C) 2019 Texas Instruments Incorporated - http://www.ti.com/ + */ + +#ifndef __LINUX_MULTICOLOR_LEDS_H_INCLUDED +#define __LINUX_MULTICOLOR_LEDS_H_INCLUDED + +#include <linux/leds.h> +#include <dt-bindings/leds/common.h> + +struct led_classdev_mc; + +struct led_mc_color_entry { + struct led_classdev_mc *mcled_cdev; + + struct device_attribute max_intensity_attr; + struct device_attribute intensity_attr; + + enum led_brightness max_intensity; + enum led_brightness intensity; + + struct list_head list; + + int led_color_id; +}; + +struct led_classdev_mc { + /* led class device */ + struct led_classdev *led_cdev; + struct list_head color_list; + + unsigned long available_colors; + int num_leds; +}; + +static inline struct led_classdev_mc *lcdev_to_mccdev( + struct led_classdev *lcdev) +{ + return container_of(lcdev, struct led_classdev_mc, led_cdev); +} + +/** + * led_classdev_multicolor_register_ext - register a new object of led_classdev + * class with support for multicolor LEDs + * @parent: the multicolor LED to register + * @mcled_cdev: the led_classdev_mc structure for this device + * @init_data: the LED class Multi color device initialization data + * + * Returns: 0 on success or negative error value on failure + */ +int led_classdev_multicolor_register_ext(struct device *parent, + struct led_classdev_mc *mcled_cdev, + struct led_init_data *init_data); + +#define led_classdev_multicolor_register(parent, mcled_cdev) \ + led_classdev_multicolor_register_ext(parent, mcled_cdev, NULL) + +/** + * led_classdev_multicolor_unregister - unregisters an object of led_classdev + * class with support for multicolor LEDs + * @mcled_cdev: the multicolor LED to unregister + * + * Unregister a previously registered via led_classdev_multicolor_register + * object + */ +void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev); + +/* Calculate brightness for the monochrome LED cluster */ +void led_mc_calc_brightness(struct led_classdev_mc *mcled_cdev, + enum led_brightness brightness, + int brightness_val[]); + +#endif /* __LINUX_MULTICOLOR_LEDS_H_INCLUDED */ -- 2.22.0.214.g8dca754b1e
