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/*

 * 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/module.h>

#include <linux/kernel.h>

#include <linux/init.h>

#include <linux/list.h>

#include <linux/spinlock.h>

#include <linux/device.h>

#include <linux/sysdev.h>

#include <linux/timer.h>

#include <linux/err.h>

#include <linux/ctype.h>

#include <linux/leds.h>

#include "leds.h"

static struct class *leds_class;

static ssize_t led_brightness_show(struct device *dev,

                struct device_attribute *attr, char *buf)

{

        struct led_classdev *led_cdev = dev_get_drvdata(dev);

        ssize_t ret = 0;

        /* no lock needed for this */

        sprintf(buf, "%u\n", led_cdev->brightness);

        ret = strlen(buf) + 1;

        return ret;

}

static ssize_t led_brightness_store(struct device *dev,

                struct device_attribute *attr, const char *buf, size_t size)

{

        struct led_classdev *led_cdev = dev_get_drvdata(dev);

        ssize_t ret = -EINVAL;

        char *after;

        unsigned long state = simple_strtoul(buf, &after, 10);

        size_t count = after - buf;

        if (*after && isspace(*after))

                count++;

        if (count == size) {

                ret = count;

                led_set_brightness(led_cdev, state);

        }

        return ret;

}

static DEVICE_ATTR(brightness, 0644, led_brightness_show, led_brightness_store);

#ifdef CONFIG_LEDS_TRIGGERS

static DEVICE_ATTR(trigger, 0644, led_trigger_show, led_trigger_store);

#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_cdev->brightness_set(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_cdev->brightness_set(led_cdev, led_cdev->brightness);

        led_cdev->flags &= ~LED_SUSPENDED;

}

EXPORT_SYMBOL_GPL(led_classdev_resume);

/**

 * led_classdev_register - register a new object of led_classdev class.

 * @dev: The device to register.

 * @led_cdev: the led_classdev structure for this device.

 */

int led_classdev_register(struct device *parent, struct led_classdev *led_cdev)

{

        int rc;

        led_cdev->dev = device_create(leds_class, parent, 0, "%s",

                                            led_cdev->name);

        if (unlikely(IS_ERR(led_cdev->dev)))

                return PTR_ERR(led_cdev->dev);

        dev_set_drvdata(led_cdev->dev, led_cdev);

        /* register the attributes */

        rc = device_create_file(led_cdev->dev, &dev_attr_brightness);

        if (rc)

                goto err_out;

        /* add to the list of leds */

        down_write(&leds_list_lock);

        list_add_tail(&led_cdev->node, &leds_list);

        up_write(&leds_list_lock);

#ifdef CONFIG_LEDS_TRIGGERS

        init_rwsem(&led_cdev->trigger_lock);

        rc = device_create_file(led_cdev->dev, &dev_attr_trigger);

        if (rc)

                goto err_out_led_list;

        led_trigger_set_default(led_cdev);

#endif

        printk(KERN_INFO "Registered led device: %s\n",

                        led_cdev->name);

        return 0;

#ifdef CONFIG_LEDS_TRIGGERS

err_out_led_list:

        device_remove_file(led_cdev->dev, &dev_attr_brightness);

        list_del(&led_cdev->node);

#endif

err_out:

        device_unregister(led_cdev->dev);

        return rc;

}

EXPORT_SYMBOL_GPL(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)

{

        device_remove_file(led_cdev->dev, &dev_attr_brightness);

#ifdef CONFIG_LEDS_TRIGGERS

        device_remove_file(led_cdev->dev, &dev_attr_trigger);

        down_write(&led_cdev->trigger_lock);

        if (led_cdev->trigger)

                led_trigger_set(led_cdev, NULL);

        up_write(&led_cdev->trigger_lock);

#endif

        device_unregister(led_cdev->dev);

        down_write(&leds_list_lock);

        list_del(&led_cdev->node);

        up_write(&leds_list_lock);

}

EXPORT_SYMBOL_GPL(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);

        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");