drivers/leds/leds-hp-disk.c

   1 /*
   2  *  leds-hp-disk.c - driver for HP "hard disk protection" LED
   3  *
   4  *  Copyright (C) 2008 Pavel Machek
   5  *
   6  *  This program is free software; you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation; either version 2 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/init.h>
  23 #include <linux/dmi.h>
  24 #include <linux/module.h>
  25 #include <linux/types.h>
  26 #include <linux/platform_device.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/input.h>
  29 #include <linux/kthread.h>
  30 #include <linux/version.h>
  31 #include <linux/leds.h>
  32 #include <acpi/acpi_drivers.h>
  33
  34 #define DRIVER_NAME     "leds-hp-disk"
  35 #define ACPI_MDPS_CLASS "led"
  36
  37 /* For automatic insertion of the module */
  38 static struct acpi_device_id hpled_device_ids[] = {
  39         {"HPQ0004", 0}, /* HP Mobile Data Protection System PNP */
  40         {"", 0},
  41 };
  42 MODULE_DEVICE_TABLE(acpi, hpled_device_ids);
  43
  44 struct acpi_hpled {
  45         struct acpi_device      *device;   /* The ACPI device */
  46 };
  47
  48 static struct acpi_hpled adev;
  49
  50 static acpi_status hpled_acpi_write(acpi_handle handle, int reg)
  51 {
  52         unsigned long ret; /* Not used when writing */
  53         union acpi_object in_obj[1];
  54         struct acpi_object_list args = { 1, in_obj };
  55
  56         in_obj[0].type          = ACPI_TYPE_INTEGER;
  57         in_obj[0].integer.value = reg;
  58
  59         return acpi_evaluate_integer(handle, "ALED", &args, &ret);
  60 }
  61
  62 static void hpled_set(struct led_classdev *led_cdev,
  63                                enum led_brightness value)
  64 {
  65         hpled_acpi_write(adev.device->handle, !!value);
  66 }
  67
  68 static struct led_classdev hpled_led = {
  69         .name                   = "hp:red:hddprotection",
  70         .default_trigger        = "heartbeat",
  71         .brightness_set         = hpled_set,
  72 };
  73
  74 #ifdef CONFIG_PM
  75 static int hpled_suspend(struct acpi_device *dev, pm_message_t state)
  76 {
  77         led_classdev_suspend(&hpled_led);
  78         return 0;
  79 }
  80
  81 static int hpled_resume(struct acpi_device *dev)
  82 {
  83         led_classdev_resume(&hpled_led);
  84         return 0;
  85 }
  86 #else
  87 #define hpled_suspend NULL
  88 #define hpled_resume NULL
  89 #endif
  90
  91 static int hpled_add(struct acpi_device *device)
  92 {
  93         int ret;
  94
  95         if (!device)
  96                 return -EINVAL;
  97
  98         adev.device = device;
  99         strcpy(acpi_device_name(device), DRIVER_NAME);
 100         strcpy(acpi_device_class(device), ACPI_MDPS_CLASS);
 101         acpi_driver_data(device) = &adev;
 102
 103         ret = led_classdev_register(NULL, &hpled_led);
 104         return ret;
 105 }
 106
 107 static int hpled_remove(struct acpi_device *device, int type)
 108 {
 109         if (!device)
 110                 return -EINVAL;
 111
 112         led_classdev_unregister(&hpled_led);
 113         return 0;
 114 }
 115
 116
 117
 118 static struct acpi_driver leds_hp_driver = {
 119         .name  = DRIVER_NAME,
 120         .class = ACPI_MDPS_CLASS,
 121         .ids   = hpled_device_ids,
 122         .ops = {
 123                 .add     = hpled_add,
 124                 .remove  = hpled_remove,
 125                 .suspend = hpled_suspend,
 126                 .resume  = hpled_resume,
 127         }
 128 };
 129
 130 static int __init hpled_init_module(void)
 131 {
 132         int ret;
 133
 134         if (acpi_disabled)
 135                 return -ENODEV;
 136
 137         ret = acpi_bus_register_driver(&leds_hp_driver);
 138         if (ret < 0)
 139                 return ret;
 140
 141         printk(KERN_INFO DRIVER_NAME " driver loaded.\n");
 142
 143         return 0;
 144 }
 145
 146 static void __exit hpled_exit_module(void)
 147 {
 148         acpi_bus_unregister_driver(&leds_hp_driver);
 149 }
 150
 151 MODULE_DESCRIPTION("Driver for HP disk protection LED");
 152 MODULE_AUTHOR("Pavel Machek <pavel@suse.cz>");
 153 MODULE_LICENSE("GPL");
 154
 155 module_init(hpled_init_module);
 156 module_exit(hpled_exit_module);