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                 led_cdev->blink_delay_on = state;
  45                 ret = count;
  46         }
  47
  48         return ret;
  49 }
  50
  51 static ssize_t led_delay_off_show(struct device *dev,
  52                 struct device_attribute *attr, char *buf)
  53 {
  54         struct led_classdev *led_cdev = dev_get_drvdata(dev);
  55
  56         return sprintf(buf, "%lu\n", led_cdev->blink_delay_off);
  57 }
  58
  59 static ssize_t led_delay_off_store(struct device *dev,
  60                 struct device_attribute *attr, const char *buf, size_t size)
  61 {
  62         struct led_classdev *led_cdev = dev_get_drvdata(dev);
  63         int ret = -EINVAL;
  64         char *after;
  65         unsigned long state = simple_strtoul(buf, &after, 10);
  66         size_t count = after - buf;
  67
  68         if (isspace(*after))
  69                 count++;
  70
  71         if (count == size) {
  72                 led_blink_set(led_cdev, &led_cdev->blink_delay_on, &state);
  73                 led_cdev->blink_delay_off = state;
  74                 ret = count;
  75         }
  76
  77         return ret;
  78 }
  79
  80 static DEVICE_ATTR(delay_on, 0644, led_delay_on_show, led_delay_on_store);
  81 static DEVICE_ATTR(delay_off, 0644, led_delay_off_show, led_delay_off_store);
  82
  83 static void timer_trig_activate(struct led_classdev *led_cdev)
  84 {
  85         int rc;
  86
  87         led_cdev->trigger_data = NULL;
  88
  89         rc = device_create_file(led_cdev->dev, &dev_attr_delay_on);
  90         if (rc)
  91                 return;
  92         rc = device_create_file(led_cdev->dev, &dev_attr_delay_off);
  93         if (rc)
  94                 goto err_out_delayon;
  95
  96         led_blink_set(led_cdev, &led_cdev->blink_delay_on,
  97                       &led_cdev->blink_delay_off);
  98
  99         led_cdev->trigger_data = (void *)1;
 100
 101         return;
 102
 103 err_out_delayon:
 104         device_remove_file(led_cdev->dev, &dev_attr_delay_on);
 105 }
 106
 107 static void timer_trig_deactivate(struct led_classdev *led_cdev)
 108 {
 109         if (led_cdev->trigger_data) {
 110                 device_remove_file(led_cdev->dev, &dev_attr_delay_on);
 111                 device_remove_file(led_cdev->dev, &dev_attr_delay_off);
 112         }
 113
 114         /* Stop blinking */
 115         led_brightness_set(led_cdev, LED_OFF);
 116 }
 117
 118 static struct led_trigger timer_led_trigger = {
 119         .name     = "timer",
 120         .activate = timer_trig_activate,
 121         .deactivate = timer_trig_deactivate,
 122 };
 123
 124 static int __init timer_trig_init(void)
 125 {
 126         return led_trigger_register(&timer_led_trigger);
 127 }
 128
 129 static void __exit timer_trig_exit(void)
 130 {
 131         led_trigger_unregister(&timer_led_trigger);
 132 }
 133
 134 module_init(timer_trig_init);
 135 module_exit(timer_trig_exit);
 136
 137 MODULE_AUTHOR("Richard Purdie <rpurdie@openedhand.com>");
 138 MODULE_DESCRIPTION("Timer LED trigger");
 139 MODULE_LICENSE("GPL");