drivers/leds/ledtrig-ide-disk.c

   1 /*
   2  * LED IDE-Disk Activity Trigger
   3  *
   4  * Copyright 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/jiffies.h>
  16 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18 #include <linux/timer.h>
  19 #include <linux/leds.h>
  20
  21 static void ledtrig_ide_timerfunc(unsigned long data);
  22
  23 DEFINE_LED_TRIGGER(ledtrig_ide);
  24 static DEFINE_TIMER(ledtrig_ide_timer, ledtrig_ide_timerfunc, 0, 0);
  25 static int ide_activity;
  26 static int ide_lastactivity;
  27
  28 void ledtrig_ide_activity(void)
  29 {
  30         ide_activity++;
  31         if (!timer_pending(&ledtrig_ide_timer))
  32                 mod_timer(&ledtrig_ide_timer, jiffies + msecs_to_jiffies(10));
  33 }
  34 EXPORT_SYMBOL(ledtrig_ide_activity);
  35
  36 static void ledtrig_ide_timerfunc(unsigned long data)
  37 {
  38         if (ide_lastactivity != ide_activity) {
  39                 ide_lastactivity = ide_activity;
  40                 /* INT_MAX will set each LED to its maximum brightness */
  41                 led_trigger_event(ledtrig_ide, INT_MAX);
  42                 mod_timer(&ledtrig_ide_timer, jiffies + msecs_to_jiffies(10));
  43         } else {
  44                 led_trigger_event(ledtrig_ide, LED_OFF);
  45         }
  46 }
  47
  48 static int __init ledtrig_ide_init(void)
  49 {
  50         led_trigger_register_simple("ide-disk", &ledtrig_ide);
  51         return 0;
  52 }
  53
  54 static void __exit ledtrig_ide_exit(void)
  55 {
  56         led_trigger_unregister_simple(ledtrig_ide);
  57 }
  58
  59 module_init(ledtrig_ide_init);
  60 module_exit(ledtrig_ide_exit);
  61
  62 MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
  63 MODULE_DESCRIPTION("LED IDE Disk Activity Trigger");
  64 MODULE_LICENSE("GPL");