Introduce a multicolor class that groups colored LEDs within a LED node. The framework allows for dynamically setting individual LEDs or setting brightness levels of LEDs and updating them virtually simultaneously. Signed-off-by: Dan Murphy <dmurphy@xxxxxx> --- v6 removed color_id and color_mix files, used sysfs_create_groups instead of kobject call for LED color directory, kept kobject_create for the "colors" directory, removed the calculate function, updated the export for the intensity calculations. drivers/leds/Kconfig | 10 + drivers/leds/Makefile | 1 + drivers/leds/led-class-multicolor.c | 306 +++++++++++++++++++++++++++ include/linux/led-class-multicolor.h | 90 ++++++++ 4 files changed, 407 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 1988de1d64c0..71e7fd4f6f15 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 41fb073a39c1..897b810257dd 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..d43bd344ed4c --- /dev/null +++ b/drivers/leds/led-class-multicolor.c @@ -0,0 +1,306 @@ +// 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" + +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; +}; + +void led_mc_calc_brightness(struct led_classdev_mc *mcled_cdev, + enum led_brightness brightness, + int brightness_val[]) +{ + struct led_classdev_mc_data *data = mcled_cdev->data; + struct led_mc_color_entry *priv; + int i = 0; + + list_for_each_entry(priv, &data->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_mc_data *data = priv->mcled_cdev->data; + struct led_classdev_mc *mcled_cdev = data->mcled_cdev; + 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; + + if (mcled_cdev->ops) { + ret = mcled_cdev->ops->set_color_brightness(mcled_cdev, + priv->led_color_id, + priv->intensity); + if (ret) + goto unlock; + } + + 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); + const struct led_multicolor_ops *ops = priv->mcled_cdev->ops; + int value = 0; + + if (ops->get_color_brightness) { + value = ops->get_color_brightness(priv->mcled_cdev, + priv->led_color_id); + priv->intensity = value; + } else { + value = priv->intensity; + } + + return sprintf(buf, "%d\n", value); +} + +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 = { + .attrs = led_color_attrs, +}; + +static int led_multicolor_init_color(struct led_classdev_mc_data *data, + 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; + 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; + + led_color_group.name = led_colors[color_id]; + ret = sysfs_create_group(data->color_kobj, &led_color_group); + if (ret) + return ret; + + sysfs_attr_init(&mc_priv->intensity_attr.attr); + mc_priv->intensity_attr.attr.name = "intensity"; + mc_priv->intensity_attr.attr.mode = 666; + mc_priv->intensity_attr.store = intensity_store; + mc_priv->intensity_attr.show = intensity_show; + ret = sysfs_add_file_to_group(data->color_kobj, + &mc_priv->intensity_attr.attr, + led_color_group.name); + if (ret) + return ret; + + sysfs_attr_init(&mc_priv->max_intensity_attr.attr); + mc_priv->max_intensity_attr.attr.name = "max_intensity"; + mc_priv->max_intensity_attr.attr.mode = 444; + mc_priv->max_intensity_attr.show = max_intensity_show; + ret = sysfs_add_file_to_group(data->color_kobj, + &mc_priv->max_intensity_attr.attr, + led_color_group.name); + if (ret) + goto err_out; + + mc_priv->max_intensity = LED_FULL; + list_add_tail(&mc_priv->list, &data->color_list); + +err_out: + return ret; +} + +static int led_multicolor_init_color_dir(struct led_classdev_mc_data *data, + struct led_classdev_mc *mcled_cdev) +{ + struct led_classdev *led_cdev = mcled_cdev->led_cdev; + u32 color_id; + int ret; + int i, j = 0; + + data->color_kobj = kobject_create_and_add("colors", + &led_cdev->dev->kobj); + if (!data->color_kobj) + return -EINVAL; + + data->mcled_cdev = mcled_cdev; + + for (i = 0; i < LED_COLOR_ID_MAX; i++) { + color_id = (mcled_cdev->available_colors & (1 << i)); + if (color_id) { + ret = led_multicolor_init_color(data, mcled_cdev, i, j); + if (ret) + break; + + j++; + } + } + + 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; + struct led_classdev_mc_data *data; + int ret; + + if (!mcled_cdev) + return -EINVAL; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + mcled_cdev->data = data; + led_cdev = mcled_cdev->led_cdev; + INIT_LIST_HEAD(&data->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(data, mcled_cdev); +} +EXPORT_SYMBOL_GPL(led_classdev_multicolor_register_ext); + +void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev) +{ + if (!mcled_cdev) + return; + + sysfs_remove_group(mcled_cdev->data->color_kobj, &led_color_group); + + kobject_del(mcled_cdev->data->color_kobj); + + 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); +} + +/** + * devm_of_led_classdev_register - resource managed led_classdev_register() + * + * @parent: parent of LED device + * @led_cdev: the led_classdev structure for this device. + */ +int devm_led_classdev_multicolor_register(struct device *parent, + struct led_classdev_mc *mcled_cdev) +{ + 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(parent, mcled_cdev); + if (ret) { + devres_free(dr); + return ret; + } + + *dr = mcled_cdev; + devres_add(parent, dr); + + return 0; +} +EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_register); + +static int devm_led_classdev_multicolor_match(struct device *dev, + void *res, void *data) +{ + struct mcled_cdev **p = res; + + if (WARN_ON(!p || !*p)) + return 0; + + return *p == data; +} + +/** + * devm_led_classdev_multicolor_unregister() - resource managed + * led_classdev_multicolor_unregister() + * @parent: The device to unregister. + * @mcled_cdev: the led_classdev_mc structure for this device. + */ +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@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..43270b3b7736 --- /dev/null +++ b/include/linux/led-class-multicolor.h @@ -0,0 +1,90 @@ +/* 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_classdev_mc_data { + struct led_classdev_mc *mcled_cdev; + + struct kobject *color_kobj; + struct kobject *led_kobj; + + struct device_attribute color_mix_attr; + + struct list_head color_list; +}; + +struct led_multicolor_ops { + /* Set brightness for a specific color id */ + int (*set_color_brightness)(struct led_classdev_mc *mcled_cdev, + int color_id, int value); + /* Read current color setting */ + int (*get_color_brightness)(struct led_classdev_mc *mcled_cdev, + int color_id); +}; + +struct led_classdev_mc { + /* led class device */ + struct led_classdev *led_cdev; + + /* multicolor led specific ops */ + struct led_multicolor_ops *ops; + + struct led_classdev_mc_data *data; + + 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 + */ +extern 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 + */ +extern void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev); + +extern int devm_led_classdev_multicolor_register(struct device *parent, + struct led_classdev_mc *mcled_cdev); + +extern void devm_led_classdev_multicolor_unregister(struct device *parent, + struct led_classdev_mc *mcled_cdev); + +/* Set brightness for the monochrome LED cluster */ +extern 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