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// SPDX-License-Identifier: GPL-2.0-only
/*
* LED Class Core
*
* Copyright (C) 2005 John Lenz <lenz@cs.wisc.edu>
* Copyright (C) 2005-2007 Richard Purdie <rpurdie@openedhand.com>
*/
#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/property.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/timer.h>
#include <uapi/linux/uleds.h>
#include <linux/of.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);
flush_work(&led_cdev->set_brightness_work);
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 BIN_ATTR(trigger, 0644, led_trigger_read, led_trigger_write, 0);
static struct bin_attribute *led_trigger_bin_attrs[] = {
&bin_attr_trigger,
NULL,
};
static const struct attribute_group led_trigger_group = {
.bin_attrs = led_trigger_bin_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);
flush_work(&led_cdev->set_brightness_work);
}
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);
/**
* of_led_get() - request a LED device via the LED framework
* @np: device node to get the LED device from
* @index: the index of the LED
*
* Returns the LED device parsed from the phandle specified in the "leds"
* property of a device tree node or a negative error-code on failure.
*/
struct led_classdev *of_led_get(struct device_node *np, int index)
{
struct device *led_dev;
struct led_classdev *led_cdev;
struct device_node *led_node;
led_node = of_parse_phandle(np, "leds", index);
if (!led_node)
return ERR_PTR(-ENOENT);
led_dev = class_find_device_by_of_node(leds_class, led_node);
of_node_put(led_node);
if (!led_dev)
return ERR_PTR(-EPROBE_DEFER);
led_cdev = dev_get_drvdata(led_dev);
if (!try_module_get(led_cdev->dev->parent->driver->owner))
return ERR_PTR(-ENODEV);
return led_cdev;
}
EXPORT_SYMBOL_GPL(of_led_get);
/**
* led_put() - release a LED device
* @led_cdev: LED device
*/
void led_put(struct led_classdev *led_cdev)
{
module_put(led_cdev->dev->parent->driver->owner);
}
EXPORT_SYMBOL_GPL(led_put);
static void devm_led_release(struct device *dev, void *res)
{
struct led_classdev **p = res;
led_put(*p);
}
/**
* devm_of_led_get - Resource-managed request of a LED device
* @dev: LED consumer
* @index: index of the LED to obtain in the consumer
*
* The device node of the device is parse to find the request LED device.
* The LED device returned from this function is automatically released
* on driver detach.
*
* @return a pointer to a LED device or ERR_PTR(errno) on failure.
*/
struct led_classdev *__must_check devm_of_led_get(struct device *dev,
int index)
{
struct led_classdev *led;
struct
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