Jacek
On 9/21/19 8:30 AM, Jacek Anaszewski wrote:
Dan,
On 9/20/19 7:41 PM, Dan Murphy wrote:
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.
Let's update this to the corresponding changed fragment from
the documentation after we finally agree upon it.
Ack
Signed-off-by: Dan Murphy <dmurphy@xxxxxx>
---
drivers/leds/Kconfig | 10 +
drivers/leds/Makefile | 1 +
drivers/leds/led-class-multicolor.c | 316 +++++++++++++++++++++++++++
include/linux/led-class-multicolor.h | 76 +++++++
4 files changed, 403 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..5e0e3fce482b
--- /dev/null
+++ b/drivers/leds/led-class-multicolor.c
@@ -0,0 +1,316 @@
+// 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"
+
+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->set_color_brightness) {
We will not have this, as discussed.
Ack this will be removed in v9
+ ret = mcled_cdev->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);
+
+ 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_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;
+ 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) {
+ ret = -ENOMEM;
+ goto err_out;
Just return -ENOMEM. No need for err_out label.
Ack
+ }
+
+ 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, &data->color_list);
+
+max_intensity_err_out:
+ kfree(max_intensity_file_name);
+intensity_err_out:
+ kfree(intensity_file_name);
+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->mcled_cdev = mcled_cdev;
+
+ ret = sysfs_create_group(&led_cdev->dev->kobj, &led_color_group);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < LED_COLOR_ID_MAX; i++) {
+ color_id = (mcled_cdev->available_colors & (1 << i));
This is nitpicking but for me it would look cleaner if we had
color_mask variable:
color_id = (mcled_cdev->available_colors & color_mask);
+ if (color_id) {
+ ret = led_multicolor_init_color(data, mcled_cdev, i, j);
+ if (ret)
+ break;
+
+ j++;
+ }
And do the shifting here:
color_mask <<= 1;
Ack but responded to your follow up email on using bit ops.
+ }
+
+ 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->led_cdev->dev->kobj, &led_color_group);
+ 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.
+ */
Let's move documentation to the header. We should to the same with
the existing led-class.c API one day.
Well this will go away if we remove the non-ext function.
And this documentation needs to be updated anyway.
+int devm_led_classdev_multicolor_register(struct device *parent,
+ struct led_classdev_mc *mcled_cdev)
We don't need non-ext version for a new API.
So we only need the ext version like in the flash class?
+{
+ 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..afcaf429fba5
--- /dev/null
+++ b/include/linux/led-class-multicolor.h
@@ -0,0 +1,76 @@
+/* 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 list_head color_list;
+};
+
+struct led_classdev_mc {
+ /* led class device */
+ struct led_classdev *led_cdev;
+
+ /* Set brightness for a specific color id */
+ int (*set_color_brightness)(struct led_classdev_mc *mcled_cdev,
+ int color_id, int value);
+
+ 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,
extern is implied by default for functions. We need also to do this
cleanup in leds.h soem day.
For clarity we can remove extern from all the APIs in the header?
Dan
+ 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 */