ledtrig-timer.c

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/*
 * LED Kernel Timer Trigger
 *
 * Copyright 2005-2006 Openedhand Ltd.
 *
 * Author: Richard Purdie <[email protected]>
 *
 * 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/device.h>
#include <linux/ctype.h>
#include <linux/leds.h>
#include "leds.h"

static ssize_t led_delay_on_show(struct device *dev,
        struct device_attribute *attr, char *buf)
{
    struct led_classdev *led_cdev = dev_get_drvdata(dev);

    return sprintf(buf, "%lu\n", led_cdev->blink_delay_on);
}

static ssize_t led_delay_on_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 = -EINVAL;

    ret = kstrtoul(buf, 10, &state);
    if (ret)
        return ret;

    led_blink_set(led_cdev, &state, &led_cdev->blink_delay_off);
    led_cdev->blink_delay_on = state;

    return size;
}

static ssize_t led_delay_off_show(struct device *dev,
        struct device_attribute *attr, char *buf)
{
    struct led_classdev *led_cdev = dev_get_drvdata(dev);

    return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
}

static ssize_t led_delay_off_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 = -EINVAL;

    ret = kstrtoul(buf, 10, &state);
    if (ret)
        return ret;

    led_blink_set(led_cdev, &led_cdev->blink_delay_on, &state);
    led_cdev->blink_delay_off = state;

    return size;
}

static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);

static void timer_trig_activate(struct led_classdev *led_cdev)
{
    int rc;

    led_cdev->trigger_data = NULL;

    rc = device_create_file(led_cdev->dev, &dev_attr_delay_on);
    if (rc)
        return;
    rc = device_create_file(led_cdev->dev, &dev_attr_delay_off);
    if (rc)
        goto err_out_delayon;

    led_blink_set(led_cdev, &led_cdev->blink_delay_on,
              &led_cdev->blink_delay_off);
    led_cdev->activated = true;

    return;

err_out_delayon:
    device_remove_file(led_cdev->dev, &dev_attr_delay_on);
}

static void timer_trig_deactivate(struct led_classdev *led_cdev)
{
    if (led_cdev->activated) {
        device_remove_file(led_cdev->dev, &dev_attr_delay_on);
        device_remove_file(led_cdev->dev, &dev_attr_delay_off);
        led_cdev->activated = false;
    }

    /* Stop blinking */
    led_set_brightness(led_cdev, LED_OFF);
}

static struct led_trigger timer_led_trigger = {
    .name     = "timer",
    .activate = timer_trig_activate,
    .deactivate = timer_trig_deactivate,
};

static int __init timer_trig_init(void)
{
    return led_trigger_register(&timer_led_trigger);
}

static void __exit timer_trig_exit(void)
{
    led_trigger_unregister(&timer_led_trigger);
}

module_init(timer_trig_init);
module_exit(timer_trig_exit);

MODULE_AUTHOR("Richard Purdie <[email protected]>");
MODULE_DESCRIPTION("Timer LED trigger");
MODULE_LICENSE("GPL");