v4.19.13 snapshot.
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
new file mode 100644
index 0000000..3c7e348
--- /dev/null
+++ b/drivers/leds/led-class.c
@@ -0,0 +1,434 @@
+/*
+ * LED Class Core
+ *
+ * Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
+ * Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/ctype.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <uapi/linux/uleds.h>
+#include "leds.h"
+
+static struct class *leds_class;
+
+static ssize_t brightness_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+ /* no lock needed for this */
+ led_update_brightness(led_cdev);
+
+ return sprintf(buf, "%u\n", led_cdev->brightness);
+}
+
+static ssize_t brightness_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ unsigned long state;
+ ssize_t ret;
+
+ mutex_lock(&led_cdev->led_access);
+
+ if (led_sysfs_is_disabled(led_cdev)) {
+ ret = -EBUSY;
+ goto unlock;
+ }
+
+ ret = kstrtoul(buf, 10, &state);
+ if (ret)
+ goto unlock;
+
+ if (state == LED_OFF)
+ led_trigger_remove(led_cdev);
+ led_set_brightness(led_cdev, state);
+
+ ret = size;
+unlock:
+ mutex_unlock(&led_cdev->led_access);
+ return ret;
+}
+static DEVICE_ATTR_RW(brightness);
+
+static ssize_t max_brightness_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", led_cdev->max_brightness);
+}
+static DEVICE_ATTR_RO(max_brightness);
+
+#ifdef CONFIG_LEDS_TRIGGERS
+static DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);
+static struct attribute *led_trigger_attrs[] = {
+ &dev_attr_trigger.attr,
+ NULL,
+};
+static const struct attribute_group led_trigger_group = {
+ .attrs = led_trigger_attrs,
+};
+#endif
+
+static struct attribute *led_class_attrs[] = {
+ &dev_attr_brightness.attr,
+ &dev_attr_max_brightness.attr,
+ NULL,
+};
+
+static const struct attribute_group led_group = {
+ .attrs = led_class_attrs,
+};
+
+static const struct attribute_group *led_groups[] = {
+ &led_group,
+#ifdef CONFIG_LEDS_TRIGGERS
+ &led_trigger_group,
+#endif
+ NULL,
+};
+
+#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
+static ssize_t brightness_hw_changed_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+ if (led_cdev->brightness_hw_changed == -1)
+ return -ENODATA;
+
+ return sprintf(buf, "%u\n", led_cdev->brightness_hw_changed);
+}
+
+static DEVICE_ATTR_RO(brightness_hw_changed);
+
+static int led_add_brightness_hw_changed(struct led_classdev *led_cdev)
+{
+ struct device *dev = led_cdev->dev;
+ int ret;
+
+ ret = device_create_file(dev, &dev_attr_brightness_hw_changed);
+ if (ret) {
+ dev_err(dev, "Error creating brightness_hw_changed\n");
+ return ret;
+ }
+
+ led_cdev->brightness_hw_changed_kn =
+ sysfs_get_dirent(dev->kobj.sd, "brightness_hw_changed");
+ if (!led_cdev->brightness_hw_changed_kn) {
+ dev_err(dev, "Error getting brightness_hw_changed kn\n");
+ device_remove_file(dev, &dev_attr_brightness_hw_changed);
+ return -ENXIO;
+ }
+
+ return 0;
+}
+
+static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev)
+{
+ sysfs_put(led_cdev->brightness_hw_changed_kn);
+ device_remove_file(led_cdev->dev, &dev_attr_brightness_hw_changed);
+}
+
+void led_classdev_notify_brightness_hw_changed(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ if (WARN_ON(!led_cdev->brightness_hw_changed_kn))
+ return;
+
+ led_cdev->brightness_hw_changed = brightness;
+ sysfs_notify_dirent(led_cdev->brightness_hw_changed_kn);
+}
+EXPORT_SYMBOL_GPL(led_classdev_notify_brightness_hw_changed);
+#else
+static int led_add_brightness_hw_changed(struct led_classdev *led_cdev)
+{
+ return 0;
+}
+static void led_remove_brightness_hw_changed(struct led_classdev *led_cdev)
+{
+}
+#endif
+
+/**
+ * led_classdev_suspend - suspend an led_classdev.
+ * @led_cdev: the led_classdev to suspend.
+ */
+void led_classdev_suspend(struct led_classdev *led_cdev)
+{
+ led_cdev->flags |= LED_SUSPENDED;
+ led_set_brightness_nopm(led_cdev, 0);
+}
+EXPORT_SYMBOL_GPL(led_classdev_suspend);
+
+/**
+ * led_classdev_resume - resume an led_classdev.
+ * @led_cdev: the led_classdev to resume.
+ */
+void led_classdev_resume(struct led_classdev *led_cdev)
+{
+ led_set_brightness_nopm(led_cdev, led_cdev->brightness);
+
+ if (led_cdev->flash_resume)
+ led_cdev->flash_resume(led_cdev);
+
+ led_cdev->flags &= ~LED_SUSPENDED;
+}
+EXPORT_SYMBOL_GPL(led_classdev_resume);
+
+#ifdef CONFIG_PM_SLEEP
+static int led_suspend(struct device *dev)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+ if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
+ led_classdev_suspend(led_cdev);
+
+ return 0;
+}
+
+static int led_resume(struct device *dev)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+
+ if (led_cdev->flags & LED_CORE_SUSPENDRESUME)
+ led_classdev_resume(led_cdev);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(leds_class_dev_pm_ops, led_suspend, led_resume);
+
+static int match_name(struct device *dev, const void *data)
+{
+ if (!dev_name(dev))
+ return 0;
+ return !strcmp(dev_name(dev), (char *)data);
+}
+
+static int led_classdev_next_name(const char *init_name, char *name,
+ size_t len)
+{
+ unsigned int i = 0;
+ int ret = 0;
+ struct device *dev;
+
+ strlcpy(name, init_name, len);
+
+ while ((ret < len) &&
+ (dev = class_find_device(leds_class, NULL, name, match_name))) {
+ put_device(dev);
+ ret = snprintf(name, len, "%s_%u", init_name, ++i);
+ }
+
+ if (ret >= len)
+ return -ENOMEM;
+
+ return i;
+}
+
+/**
+ * of_led_classdev_register - register a new object of led_classdev class.
+ *
+ * @parent: parent of LED device
+ * @led_cdev: the led_classdev structure for this device.
+ * @np: DT node describing this LED
+ */
+int of_led_classdev_register(struct device *parent, struct device_node *np,
+ struct led_classdev *led_cdev)
+{
+ char name[LED_MAX_NAME_SIZE];
+ int ret;
+
+ ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
+ if (ret < 0)
+ return ret;
+
+ mutex_init(&led_cdev->led_access);
+ mutex_lock(&led_cdev->led_access);
+ led_cdev->dev = device_create_with_groups(leds_class, parent, 0,
+ led_cdev, led_cdev->groups, "%s", name);
+ if (IS_ERR(led_cdev->dev)) {
+ mutex_unlock(&led_cdev->led_access);
+ return PTR_ERR(led_cdev->dev);
+ }
+ led_cdev->dev->of_node = np;
+
+ if (ret)
+ dev_warn(parent, "Led %s renamed to %s due to name collision",
+ led_cdev->name, dev_name(led_cdev->dev));
+
+ if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) {
+ ret = led_add_brightness_hw_changed(led_cdev);
+ if (ret) {
+ device_unregister(led_cdev->dev);
+ mutex_unlock(&led_cdev->led_access);
+ return ret;
+ }
+ }
+
+ led_cdev->work_flags = 0;
+#ifdef CONFIG_LEDS_TRIGGERS
+ init_rwsem(&led_cdev->trigger_lock);
+#endif
+#ifdef CONFIG_LEDS_BRIGHTNESS_HW_CHANGED
+ led_cdev->brightness_hw_changed = -1;
+#endif
+ /* add to the list of leds */
+ down_write(&leds_list_lock);
+ list_add_tail(&led_cdev->node, &leds_list);
+ up_write(&leds_list_lock);
+
+ if (!led_cdev->max_brightness)
+ led_cdev->max_brightness = LED_FULL;
+
+ led_update_brightness(led_cdev);
+
+ led_init_core(led_cdev);
+
+#ifdef CONFIG_LEDS_TRIGGERS
+ led_trigger_set_default(led_cdev);
+#endif
+
+ mutex_unlock(&led_cdev->led_access);
+
+ dev_dbg(parent, "Registered led device: %s\n",
+ led_cdev->name);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_led_classdev_register);
+
+/**
+ * led_classdev_unregister - unregisters a object of led_properties class.
+ * @led_cdev: the led device to unregister
+ *
+ * Unregisters a previously registered via led_classdev_register object.
+ */
+void led_classdev_unregister(struct led_classdev *led_cdev)
+{
+#ifdef CONFIG_LEDS_TRIGGERS
+ down_write(&led_cdev->trigger_lock);
+ if (led_cdev->trigger)
+ led_trigger_set(led_cdev, NULL);
+ up_write(&led_cdev->trigger_lock);
+#endif
+
+ led_cdev->flags |= LED_UNREGISTERING;
+
+ /* Stop blinking */
+ led_stop_software_blink(led_cdev);
+
+ led_set_brightness(led_cdev, LED_OFF);
+
+ flush_work(&led_cdev->set_brightness_work);
+
+ if (led_cdev->flags & LED_BRIGHT_HW_CHANGED)
+ led_remove_brightness_hw_changed(led_cdev);
+
+ device_unregister(led_cdev->dev);
+
+ down_write(&leds_list_lock);
+ list_del(&led_cdev->node);
+ up_write(&leds_list_lock);
+
+ mutex_destroy(&led_cdev->led_access);
+}
+EXPORT_SYMBOL_GPL(led_classdev_unregister);
+
+static void devm_led_classdev_release(struct device *dev, void *res)
+{
+ led_classdev_unregister(*(struct led_classdev **)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_of_led_classdev_register(struct device *parent,
+ struct device_node *np,
+ struct led_classdev *led_cdev)
+{
+ struct led_classdev **dr;
+ int rc;
+
+ dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL);
+ if (!dr)
+ return -ENOMEM;
+
+ rc = of_led_classdev_register(parent, np, led_cdev);
+ if (rc) {
+ devres_free(dr);
+ return rc;
+ }
+
+ *dr = led_cdev;
+ devres_add(parent, dr);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(devm_of_led_classdev_register);
+
+static int devm_led_classdev_match(struct device *dev, void *res, void *data)
+{
+ struct led_cdev **p = res;
+
+ if (WARN_ON(!p || !*p))
+ return 0;
+
+ return *p == data;
+}
+
+/**
+ * devm_led_classdev_unregister() - resource managed led_classdev_unregister()
+ * @parent: The device to unregister.
+ * @led_cdev: the led_classdev structure for this device.
+ */
+void devm_led_classdev_unregister(struct device *dev,
+ struct led_classdev *led_cdev)
+{
+ WARN_ON(devres_release(dev,
+ devm_led_classdev_release,
+ devm_led_classdev_match, led_cdev));
+}
+EXPORT_SYMBOL_GPL(devm_led_classdev_unregister);
+
+static int __init leds_init(void)
+{
+ leds_class = class_create(THIS_MODULE, "leds");
+ if (IS_ERR(leds_class))
+ return PTR_ERR(leds_class);
+ leds_class->pm = &leds_class_dev_pm_ops;
+ leds_class->dev_groups = led_groups;
+ return 0;
+}
+
+static void __exit leds_exit(void)
+{
+ class_destroy(leds_class);
+}
+
+subsys_initcall(leds_init);
+module_exit(leds_exit);
+
+MODULE_AUTHOR("John Lenz, Richard Purdie");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("LED Class Interface");