mirror of
https://github.com/torvalds/linux.git
synced 2024-12-05 10:32:35 +00:00
495b8966f7
Update a newly created device's fwnode and of_node pointers using the recently added device_set_node helper. This keeps some firmware node specifics out of led-class and should help tracking future changes regarding device firmware node updates. Signed-off-by: Sander Vanheule <sander@svanheule.net> Signed-off-by: Pavel Machek <pavel@ucw.cz>
549 lines
13 KiB
C
549 lines
13 KiB
C
// 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, unsigned int 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 led_classdev **dr;
|
|
|
|
if (!dev)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
led = of_led_get(dev->of_node, index);
|
|
if (IS_ERR(led))
|
|
return led;
|
|
|
|
dr = devres_alloc(devm_led_release, sizeof(struct led_classdev *),
|
|
GFP_KERNEL);
|
|
if (!dr) {
|
|
led_put(led);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
*dr = led;
|
|
devres_add(dev, dr);
|
|
|
|
return led;
|
|
}
|
|
EXPORT_SYMBOL_GPL(devm_of_led_get);
|
|
|
|
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_by_name(leds_class, name))) {
|
|
put_device(dev);
|
|
ret = snprintf(name, len, "%s_%u", init_name, ++i);
|
|
}
|
|
|
|
if (ret >= len)
|
|
return -ENOMEM;
|
|
|
|
return i;
|
|
}
|
|
|
|
/**
|
|
* led_classdev_register_ext - register a new object of led_classdev class
|
|
* with init data.
|
|
*
|
|
* @parent: parent of LED device
|
|
* @led_cdev: the led_classdev structure for this device.
|
|
* @init_data: LED class device initialization data
|
|
*/
|
|
int led_classdev_register_ext(struct device *parent,
|
|
struct led_classdev *led_cdev,
|
|
struct led_init_data *init_data)
|
|
{
|
|
char composed_name[LED_MAX_NAME_SIZE];
|
|
char final_name[LED_MAX_NAME_SIZE];
|
|
const char *proposed_name = composed_name;
|
|
int ret;
|
|
|
|
if (init_data) {
|
|
if (init_data->devname_mandatory && !init_data->devicename) {
|
|
dev_err(parent, "Mandatory device name is missing");
|
|
return -EINVAL;
|
|
}
|
|
ret = led_compose_name(parent, init_data, composed_name);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (init_data->fwnode) {
|
|
fwnode_property_read_string(init_data->fwnode,
|
|
"linux,default-trigger",
|
|
&led_cdev->default_trigger);
|
|
|
|
if (fwnode_property_present(init_data->fwnode,
|
|
"retain-state-shutdown"))
|
|
led_cdev->flags |= LED_RETAIN_AT_SHUTDOWN;
|
|
}
|
|
} else {
|
|
proposed_name = led_cdev->name;
|
|
}
|
|
|
|
ret = led_classdev_next_name(proposed_name, final_name, sizeof(final_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", final_name);
|
|
if (IS_ERR(led_cdev->dev)) {
|
|
mutex_unlock(&led_cdev->led_access);
|
|
return PTR_ERR(led_cdev->dev);
|
|
}
|
|
if (init_data && init_data->fwnode)
|
|
device_set_node(led_cdev->dev, init_data->fwnode);
|
|
|
|
if (ret)
|
|
dev_warn(parent, "Led %s renamed to %s due to name collision",
|
|
proposed_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);
|
|
led_cdev->dev = NULL;
|
|
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(led_classdev_register_ext);
|
|
|
|
/**
|
|
* 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)
|
|
{
|
|
if (IS_ERR_OR_NULL(led_cdev->dev))
|
|
return;
|
|
|
|
#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);
|
|
|
|
if (!(led_cdev->flags & LED_RETAIN_AT_SHUTDOWN))
|
|
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_led_classdev_register_ext - resource managed led_classdev_register_ext()
|
|
*
|
|
* @parent: parent of LED device
|
|
* @led_cdev: the led_classdev structure for this device.
|
|
* @init_data: LED class device initialization data
|
|
*/
|
|
int devm_led_classdev_register_ext(struct device *parent,
|
|
struct led_classdev *led_cdev,
|
|
struct led_init_data *init_data)
|
|
{
|
|
struct led_classdev **dr;
|
|
int rc;
|
|
|
|
dr = devres_alloc(devm_led_classdev_release, sizeof(*dr), GFP_KERNEL);
|
|
if (!dr)
|
|
return -ENOMEM;
|
|
|
|
rc = led_classdev_register_ext(parent, led_cdev, init_data);
|
|
if (rc) {
|
|
devres_free(dr);
|
|
return rc;
|
|
}
|
|
|
|
*dr = led_cdev;
|
|
devres_add(parent, dr);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(devm_led_classdev_register_ext);
|
|
|
|
static int devm_led_classdev_match(struct device *dev, void *res, void *data)
|
|
{
|
|
struct led_classdev **p = res;
|
|
|
|
if (WARN_ON(!p || !*p))
|
|
return 0;
|
|
|
|
return *p == data;
|
|
}
|
|
|
|
/**
|
|
* devm_led_classdev_unregister() - resource managed led_classdev_unregister()
|
|
* @dev: 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");
|