drivers/leds/ledtrig-timer.c

   1 /*
   2  * LED Kernel Timer Trigger
   3  *
   4  * Copyright 2005-2006 Openedhand Ltd.
   5  *
   6  * Author: Richard Purdie <rpurdie@openedhand.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  *
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/kernel.h>
  16 #include <linux/init.h>
  17 #include <linux/device.h>
  18 #include <linux/ctype.h>
  19 #include <linux/leds.h>
  20 #include "leds.h"
  21
  22 static ssize_t led_delay_on_show(struct device *dev,
  23                 struct device_attribute *attr, char *buf)
  24 {
  25         struct led_classdev *led_cdev = dev_get_drvdata(dev);
  26
  27         return sprintf(buf, "%lu\n", led_cdev->blink_delay_on);
  28 }
  29
  30 static ssize_t led_delay_on_store(struct device *dev,
  31                 struct device_attribute *attr, const char *buf, size_t size)
  32 {
  33         struct led_classdev *led_cdev = dev_get_drvdata(dev);
  34         unsigned long state;
  35         ssize_t ret = -EINVAL;
  36
  37         ret = kstrtoul(buf, 10, &state);
  38         if (ret)
  39                 return ret;
  40
  41         led_blink_set(led_cdev, &state, &led_cdev->blink_delay_off);
  42         led_cdev->blink_delay_on = state;
  43
  44         return size;
  45 }
  46
  47 static ssize_t led_delay_off_show(struct device *dev,
  48                 struct device_attribute *attr, char *buf)
  49 {
  50         struct led_classdev *led_cdev = dev_get_drvdata(dev);
  51
  52         return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
  53 }
  54
  55 static ssize_t led_delay_off_store(struct device *dev,
  56                 struct device_attribute *attr, const char *buf, size_t size)
  57 {
  58         struct led_classdev *led_cdev = dev_get_drvdata(dev);
  59         unsigned long state;
  60         ssize_t ret = -EINVAL;
  61
  62         ret = kstrtoul(buf, 10, &state);
  63         if (ret)
  64                 return ret;
  65
  66         led_blink_set(led_cdev, &led_cdev->blink_delay_on, &state);
  67         led_cdev->blink_delay_off = state;
  68
  69         return size;
  70 }
  71
  72 static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
  73 static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
  74
  75 static void timer_trig_activate(struct led_classdev *led_cdev)
  76 {
  77         int rc;
  78
  79         led_cdev->trigger_data = NULL;
  80
  81         rc = device_create_file(led_cdev->dev, &dev_attr_delay_on);
  82         if (rc)
  83                 return;
  84         rc = device_create_file(led_cdev->dev, &dev_attr_delay_off);
  85         if (rc)
  86                 goto err_out_delayon;
  87
  88         led_blink_set(led_cdev, &led_cdev->blink_delay_on,
  89                       &led_cdev->blink_delay_off);
  90         led_cdev->activated = true;
  91
  92         return;
  93
  94 err_out_delayon:
  95         device_remove_file(led_cdev->dev, &dev_attr_delay_on);
  96 }
  97
  98 static void timer_trig_deactivate(struct led_classdev *led_cdev)
  99 {
 100         if (led_cdev->activated) {
 101                 device_remove_file(led_cdev->dev, &dev_attr_delay_on);
 102                 device_remove_file(led_cdev->dev, &dev_attr_delay_off);
 103                 led_cdev->activated = false;
 104         }
 105
 106         /* Stop blinking */
 107         led_set_brightness(led_cdev, LED_OFF);
 108 }
 109
 110 static struct led_trigger timer_led_trigger = {
 111         .name     = "timer",
 112         .activate = timer_trig_activate,
 113         .deactivate = timer_trig_deactivate,
 114 };
 115
 116 static int __init timer_trig_init(void)
 117 {
 118         return led_trigger_register(&timer_led_trigger);
 119 }
 120
 121 static void __exit timer_trig_exit(void)
 122 {
 123         led_trigger_unregister(&timer_led_trigger);
 124 }
 125
 126 module_init(timer_trig_init);
 127 module_exit(timer_trig_exit);
 128
 129 MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
 130 MODULE_DESCRIPTION("Timer LED trigger");
 131 MODULE_LICENSE("GPL");