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         int ret = -EINVAL;
  35         char *after;
  36         unsigned long state = simple_strtoul(buf, &after, 10);
  37         size_t count = after - buf;
  38
  39         if (isspace(*after))
  40                 count++;
  41
  42         if (count == size) {
  43                 led_blink_set(led_cdev, &state, &led_cdev->blink_delay_off);
  44                 ret = count;
  45         }
  46
  47         return ret;
  48 }
  49
  50 static ssize_t led_delay_off_show(struct device *dev,
  51                 struct device_attribute *attr, char *buf)
  52 {
  53         struct led_classdev *led_cdev = dev_get_drvdata(dev);
  54
  55         return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
  56 }
  57
  58 static ssize_t led_delay_off_store(struct device *dev,
  59                 struct device_attribute *attr, const char *buf, size_t size)
  60 {
  61         struct led_classdev *led_cdev = dev_get_drvdata(dev);
  62         int ret = -EINVAL;
  63         char *after;
  64         unsigned long state = simple_strtoul(buf, &after, 10);
  65         size_t count = after - buf;
  66
  67         if (isspace(*after))
  68                 count++;
  69
  70         if (count == size) {
  71                 led_blink_set(led_cdev, &led_cdev->blink_delay_on, &state);
  72                 ret = count;
  73         }
  74
  75         return ret;
  76 }
  77
  78 static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
  79 static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
  80
  81 static void timer_trig_activate(struct led_classdev *led_cdev)
  82 {
  83         int rc;
  84
  85         led_cdev->trigger_data = NULL;
  86
  87         rc = device_create_file(led_cdev->dev, &dev_attr_delay_on);
  88         if (rc)
  89                 return;
  90         rc = device_create_file(led_cdev->dev, &dev_attr_delay_off);
  91         if (rc)
  92                 goto err_out_delayon;
  93
  94         led_cdev->trigger_data = (void *)1;
  95
  96         return;
  97
  98 err_out_delayon:
  99         device_remove_file(led_cdev->dev, &dev_attr_delay_on);
 100 }
 101
 102 static void timer_trig_deactivate(struct led_classdev *led_cdev)
 103 {
 104         if (led_cdev->trigger_data) {
 105                 device_remove_file(led_cdev->dev, &dev_attr_delay_on);
 106                 device_remove_file(led_cdev->dev, &dev_attr_delay_off);
 107         }
 108
 109         /* Stop blinking */
 110         led_brightness_set(led_cdev, LED_OFF);
 111 }
 112
 113 static struct led_trigger timer_led_trigger = {
 114         .name     = "timer",
 115         .activate = timer_trig_activate,
 116         .deactivate = timer_trig_deactivate,
 117 };
 118
 119 static int __init timer_trig_init(void)
 120 {
 121         return led_trigger_register(&timer_led_trigger);
 122 }
 123
 124 static void __exit timer_trig_exit(void)
 125 {
 126         led_trigger_unregister(&timer_led_trigger);
 127 }
 128
 129 module_init(timer_trig_init);
 130 module_exit(timer_trig_exit);
 131
 132 MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
 133 MODULE_DESCRIPTION("Timer LED trigger");
 134 MODULE_LICENSE("GPL");