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> --- drivers/leds/Kconfig | 10 + drivers/leds/Makefile | 1 + drivers/leds/led-class-multicolor.c | 421 +++++++++++++++++++++++++++ include/linux/led-class-multicolor.h | 95 ++++++ 4 files changed, 527 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 0414adebb177..0696a13c9527 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -29,6 +29,16 @@ 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 4c1b0054f379..c57c2aec9510 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..3f989e552d09 --- /dev/null +++ b/drivers/leds/led-class-multicolor.c @@ -0,0 +1,421 @@ +// 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 "leds.h" + +struct led_classdev_mc_priv { + struct led_classdev_mc *mcled_cdev; + + struct device_attribute max_brightness_attr; + struct device_attribute brightness_attr; + + enum led_brightness max_brightness; + enum led_brightness brightness; + enum led_brightness new_brightness; + struct list_head list; + + int color_id; +}; + +static ssize_t sync_store(struct device *dev, + struct device_attribute *sync_attr, + const char *buf, size_t size) +{ + struct led_classdev_mc_data *data = container_of(sync_attr, + struct led_classdev_mc_data, + sync_attr); + struct led_classdev_mc *mcled_cdev = data->mcled_cdev; + struct led_classdev *led_cdev = &mcled_cdev->led_cdev; + struct led_classdev_mc_priv *priv; + unsigned long sync_value; + ssize_t ret = -EINVAL; + + mutex_lock(&led_cdev->led_access); + + if (!mcled_cdev->sync_enabled) + goto unlock; + + ret = kstrtoul(buf, 0, &sync_value); + if (ret) + goto unlock; + + if (!sync_value) { + ret = size; + goto unlock; + } + + list_for_each_entry(priv, &data->color_list, list) + priv->brightness = priv->new_brightness; + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_access); + return ret; +} + +static ssize_t sync_enable_store(struct device *dev, + struct device_attribute *sync_enable_attr, + const char *buf, size_t size) +{ + struct led_classdev_mc_data *data = container_of(sync_enable_attr, + struct led_classdev_mc_data, + sync_enable_attr); + struct led_classdev_mc *mcled_cdev = data->mcled_cdev; + struct led_classdev *led_cdev = &mcled_cdev->led_cdev; + unsigned long sync_value; + ssize_t ret; + + mutex_lock(&led_cdev->led_access); + + ret = kstrtoul(buf, 0, &sync_value); + if (ret) + goto unlock; + + mcled_cdev->sync_enabled = sync_value; + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_access); + return ret; +} + +static ssize_t sync_enable_show(struct device *dev, + struct device_attribute *sync_enable_attr, + char *buf) +{ + struct led_classdev_mc_data *data = container_of(sync_enable_attr, + struct led_classdev_mc_data, + sync_enable_attr); + struct led_classdev_mc *mcled_cdev = data->mcled_cdev; + + return sprintf(buf, "%d\n", mcled_cdev->sync_enabled); +} + +static ssize_t brightness_store(struct device *dev, + struct device_attribute *brightness_attr, + const char *buf, size_t size) +{ + struct led_classdev_mc_priv *priv = container_of(brightness_attr, + struct led_classdev_mc_priv, + brightness_attr); + struct led_classdev *led_cdev = &priv->mcled_cdev->led_cdev; + struct led_multicolor_ops *ops = priv->mcled_cdev->ops; + + 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_brightness) { + ret = -EINVAL; + goto unlock; + } + + priv->new_brightness = value; + + if (priv->mcled_cdev->sync_enabled) { + ret = size; + goto unlock; + } + + ret = ops->set_color_brightness(priv->mcled_cdev, + priv->color_id, value); + if (ret < 0) + goto unlock; + + priv->brightness = priv->new_brightness; + + ret = size; +unlock: + mutex_unlock(&led_cdev->led_access); + return ret; +} + +static ssize_t brightness_show(struct device *dev, + struct device_attribute *brightness_attr, + char *buf) +{ + struct led_classdev_mc_priv *priv = container_of(brightness_attr, + struct led_classdev_mc_priv, + brightness_attr); + const struct led_multicolor_ops *ops = priv->mcled_cdev->ops; + int value = 0; + + if (priv->mcled_cdev->sync_enabled) { + value = priv->brightness; + goto sync_enabled; + } + + if (ops->get_color_brightness) { + value = ops->get_color_brightness(priv->mcled_cdev, + priv->color_id); + priv->brightness = value; + } else { + value = priv->brightness; + } + +sync_enabled: + return sprintf(buf, "%d\n", value); +} + +static ssize_t max_brightness_show(struct device *dev, + struct device_attribute *max_brightness_attr, + char *buf) +{ + struct led_classdev_mc_priv *priv = container_of(max_brightness_attr, + struct led_classdev_mc_priv, + max_brightness_attr); + + return sprintf(buf, "%d\n", priv->max_brightness); +} + +static int multicolor_set_brightness(struct led_classdev *led_cdev, + enum led_brightness brightness) +{ + struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev); + struct led_classdev_mc_data *data = mcled_cdev->data; + struct led_multicolor_ops *ops = mcled_cdev->ops; + struct led_classdev_mc_priv *priv; + unsigned long state = brightness; + int adj_value; + ssize_t ret = -EINVAL; + + mutex_lock(&led_cdev->led_access); + + if (ops->set_module_brightness) { + ret = ops->set_module_brightness(mcled_cdev, state); + goto unlock; + } + + list_for_each_entry(priv, &data->color_list, list) { + if (state && priv->brightness && priv->max_brightness) { + adj_value = state * ((priv->brightness * 100) / priv->max_brightness); + adj_value = adj_value / 100; + } else + adj_value = LED_OFF; + + ret = ops->set_color_brightness(priv->mcled_cdev, + priv->color_id, adj_value); + if (ret < 0) + goto unlock; + } + +unlock: + mutex_unlock(&led_cdev->led_access); + return ret; +} + +static int led_multicolor_init_color(struct led_classdev_mc_data *data, + struct led_classdev_mc *mcled_cdev, + int color_id) +{ + struct led_classdev *led_cdev = &mcled_cdev->led_cdev; + struct led_classdev_mc_priv *mc_priv; + int ret; + + mc_priv = devm_kzalloc(led_cdev->dev, sizeof(*mc_priv), GFP_KERNEL); + if (!mc_priv) + return -ENOMEM; + + mc_priv->color_id = color_id; + mc_priv->mcled_cdev = mcled_cdev; + + data->led_kobj = kobject_create_and_add(led_colors[color_id], + data->color_kobj); + if (!data->led_kobj) + return -EINVAL; + + sysfs_attr_init(&mc_priv->brightness_attr.attr); + mc_priv->brightness_attr.attr.name = "brightness"; + mc_priv->brightness_attr.attr.mode = S_IRUGO | S_IWUGO; + mc_priv->brightness_attr.store = brightness_store; + mc_priv->brightness_attr.show = brightness_show; + ret = sysfs_create_file(data->led_kobj, + &mc_priv->brightness_attr.attr); + if (ret) + goto err_out; + + sysfs_attr_init(&mc_priv->max_brightness_attr.attr); + mc_priv->max_brightness_attr.attr.name = "max_brightness"; + mc_priv->max_brightness_attr.attr.mode = S_IRUGO; + mc_priv->max_brightness_attr.show = max_brightness_show; + ret = sysfs_create_file(data->led_kobj, + &mc_priv->max_brightness_attr.attr); + if (ret) + goto err_out; + + mc_priv->max_brightness = 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; + int ret; + + data->color_kobj = kobject_create_and_add("colors", + &led_cdev->dev->kobj); + if (!data->color_kobj) + return -EINVAL; + + sysfs_attr_init(&data->sync_enable_attr.attr); + data->sync_enable_attr.attr.name = "sync_enable"; + data->sync_enable_attr.attr.mode = S_IRUGO | S_IWUGO; + data->sync_enable_attr.show = sync_enable_show; + data->sync_enable_attr.store = sync_enable_store; + ret = sysfs_create_file(data->color_kobj, + &data->sync_enable_attr.attr); + if (ret) + goto err_out; + + sysfs_attr_init(&data->sync_attr.attr); + data->sync_attr.attr.name = "sync"; + data->sync_attr.attr.mode = S_IWUGO; + data->sync_attr.store = sync_store; + ret = sysfs_create_file(data->color_kobj, + &data->sync_attr.attr); + if (ret) + goto err_out; + + data->mcled_cdev = mcled_cdev; +err_out: + 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_multicolor_ops *ops; + struct led_classdev_mc_data *data; + int ret; + int i; + + if (!mcled_cdev) + return -EINVAL; + + ops = mcled_cdev->ops; + if (!ops || !ops->set_color_brightness) + return -EINVAL; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + mcled_cdev->data = data; + led_cdev = &mcled_cdev->led_cdev; + + if (led_cdev->brightness_set_blocking) + led_cdev->brightness_set_blocking = multicolor_set_brightness; + + INIT_LIST_HEAD(&data->color_list); + + /* Register led class device */ + ret = led_classdev_register_ext(parent, led_cdev, init_data); + if (ret) + return ret; + + ret = led_multicolor_init_color_dir(data, mcled_cdev); + if (ret) + return ret; + + /* Select the sysfs attributes to be created for the device */ + for (i = 0; i < mcled_cdev->num_leds; i++) { + ret = led_multicolor_init_color(data, mcled_cdev, + mcled_cdev->available_colors[i]); + if (ret) + break; + } + + return ret; +} +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); +} + +/** + * 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..f9e71d984b03 --- /dev/null +++ b/include/linux/led-class-multicolor.h @@ -0,0 +1,95 @@ +// 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 sync_attr; + struct device_attribute sync_enable_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); + /* Set brightness for the color module */ + int (*set_module_brightness)(struct led_classdev_mc *mcled_cdev, + int value); + /* Read current module brightness */ + int (*get_module_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; + + u32 available_colors[LED_COLOR_ID_COUNT]; + int num_leds; + + bool sync_enabled; +}; + +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); + +#endif /* __LINUX_MULTICOLOR_LEDS_H_INCLUDED */ -- 2.21.0.5.gaeb582a983
