[PATCH v5 6/9] leds: multicolor: Introduce a multicolor class definition
From: Dan Murphy
Date: Wed Sep 11 2019 - 14:01:32 EST
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 | 387 +++++++++++++++++++++++++++
include/linux/led-class-multicolor.h | 96 +++++++
4 files changed, 494 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..c733192b31fa
--- /dev/null
+++ b/drivers/leds/led-class-multicolor.c
@@ -0,0 +1,387 @@
+// 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_classdev_mc_priv {
+ struct led_classdev_mc *mcled_cdev;
+
+ struct device_attribute max_intensity_attr;
+ struct device_attribute intensity_attr;
+ struct device_attribute color_index_attr;
+
+ enum led_brightness max_intensity;
+ enum led_brightness intensity;
+
+ struct list_head list;
+
+ int led_color_id;
+ int color_seq_pos;
+};
+
+static int led_mc_calculate_brightness(int brightness, int intensity,
+ int max_intensity)
+{
+ if (brightness && intensity && max_intensity)
+ return brightness * intensity / max_intensity;
+
+ return LED_OFF;
+}
+
+void led_mc_set_cluster_brightness(struct led_classdev_mc *mcled_cdev,
+ enum led_brightness brightness, int adj_value[])
+{
+ struct led_classdev_mc_data *data = mcled_cdev->data;
+ struct led_classdev_mc_priv *priv;
+ int i = 0;
+
+ list_for_each_entry(priv, &data->color_list, list) {
+ adj_value[i] = led_mc_calculate_brightness(brightness,
+ priv->intensity,
+ priv->max_intensity);
+ i++;
+ }
+
+ data->cluster_brightness = brightness;
+}
+
+void led_mc_get_cluster_brightness(struct led_classdev_mc *mcled_cdev,
+ int brightness_val[])
+{
+ struct led_classdev_mc_data *data = mcled_cdev->data;
+ struct led_classdev_mc_priv *priv;
+ int i = 0;
+
+ list_for_each_entry(priv, &data->color_list, list) {
+ brightness_val[i] = priv->intensity;
+ i++;
+ }
+}
+
+static ssize_t color_index_show(struct device *dev,
+ struct device_attribute *color_index_attr,
+ char *buf)
+{
+ struct led_classdev_mc_priv *priv = container_of(color_index_attr,
+ struct led_classdev_mc_priv,
+ color_index_attr);
+
+ return sprintf(buf, "%d\n", priv->led_color_id);
+}
+
+static ssize_t color_mix_store(struct device *dev,
+ struct device_attribute *color_mix_attr,
+ const char *buf, size_t size)
+{
+ struct led_classdev_mc_data *data = container_of(color_mix_attr,
+ struct led_classdev_mc_data,
+ color_mix_attr);
+ struct led_classdev_mc *mcled_cdev = data->mcled_cdev;
+ struct led_classdev_mc_priv *priv;
+ unsigned int value[LED_COLOR_ID_MAX];
+ int nrchars, offset = 0;
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < mcled_cdev->num_leds; i++) {
+ ret = sscanf(buf + offset, "%i%n", &value[i], &nrchars);
+ if (ret != 1)
+ break;
+
+ offset += nrchars;
+ }
+
+ if (i != mcled_cdev->num_leds) {
+ dev_err(dev, "Wrong number of LEDs defined %i, need %i\n",
+ i, mcled_cdev->num_leds);
+ return -EINVAL;
+ }
+
+ list_for_each_entry(priv, &data->color_list, list) {
+ priv->intensity = value[priv->color_seq_pos];
+ if (mcled_cdev->ops) {
+ ret = mcled_cdev->ops->set_color_brightness(mcled_cdev,
+ priv->led_color_id,
+ priv->intensity);
+ if (ret)
+ goto out;
+ }
+ }
+out:
+ return size;
+}
+
+static ssize_t intensity_store(struct device *dev,
+ struct device_attribute *intensity_attr,
+ const char *buf, size_t size)
+{
+ struct led_classdev_mc_priv *priv = container_of(intensity_attr,
+ struct led_classdev_mc_priv,
+ 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_classdev_mc_priv *priv = container_of(intensity_attr,
+ struct led_classdev_mc_priv,
+ 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_classdev_mc_priv *priv = container_of(max_intensity_attr,
+ struct led_classdev_mc_priv,
+ max_intensity_attr);
+
+ return sprintf(buf, "%d\n", priv->max_intensity);
+}
+
+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_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->led_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->intensity_attr.attr);
+ mc_priv->intensity_attr.attr.name = "intensity";
+ mc_priv->intensity_attr.attr.mode = S_IRUGO | S_IWUGO;
+ mc_priv->intensity_attr.store = intensity_store;
+ mc_priv->intensity_attr.show = intensity_show;
+ ret = sysfs_create_file(data->led_kobj,
+ &mc_priv->intensity_attr.attr);
+ if (ret)
+ goto err_out;
+
+ 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 = S_IRUGO;
+ mc_priv->max_intensity_attr.show = max_intensity_show;
+ ret = sysfs_create_file(data->led_kobj,
+ &mc_priv->max_intensity_attr.attr);
+ if (ret)
+ goto err_out;
+
+ sysfs_attr_init(&mc_priv->color_index_attr.attr);
+ mc_priv->color_index_attr.attr.name = "color_id";
+ mc_priv->color_index_attr.attr.mode = S_IRUGO;
+ mc_priv->color_index_attr.show = color_index_show;
+ ret = sysfs_create_file(data->led_kobj,
+ &mc_priv->color_index_attr.attr);
+ if (ret)
+ goto err_out;
+
+ mc_priv->max_intensity = LED_FULL;
+ mc_priv->color_seq_pos = color_index;
+ 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++;
+ }
+ }
+
+ sysfs_attr_init(&data->color_mix_attr.attr);
+ data->color_mix_attr.attr.name = "color_mix";
+ data->color_mix_attr.attr.mode = S_IRUGO | S_IWUGO;
+ data->color_mix_attr.store = color_mix_store;
+ ret = sysfs_create_file(data->color_kobj,
+ &data->color_mix_attr.attr);
+
+ 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;
+
+ 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..193ba0e46042
--- /dev/null
+++ b/include/linux/led-class-multicolor.h
@@ -0,0 +1,96 @@
+/* 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;
+
+ enum led_brightness cluster_brightness;
+};
+
+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_set_cluster_brightness(struct led_classdev_mc *mcled_cdev,
+ enum led_brightness brightness,
+ int adj_value[]);
+
+/* Read current cluster brightness */
+extern void led_mc_get_cluster_brightness(struct led_classdev_mc *mcled_cdev,
+ int brightness_val[]);
+
+#endif /* __LINUX_MULTICOLOR_LEDS_H_INCLUDED */
--
2.22.0.214.g8dca754b1e