drivers/acpi/hed.c

   1 /*
   2  * ACPI Hardware Error Device (PNP0C33) Driver
   3  *
   4  * Copyright (C) 2010, Intel Corp.
   5  *      Author: Huang Ying <ying.huang@intel.com>
   6  *
   7  * ACPI Hardware Error Device is used to report some hardware errors
   8  * notified via SCI, mainly the corrected errors.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License version
  12  * 2 as published by the Free Software Foundation;
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22  */
  23
  24 #include <linux/kernel.h>
  25 #include <linux/module.h>
  26 #include <linux/init.h>
  27 #include <linux/acpi.h>
  28 #include <acpi/acpi_bus.h>
  29 #include <acpi/acpi_drivers.h>
  30 #include <acpi/hed.h>
  31
  32 static struct acpi_device_id acpi_hed_ids[] = {
  33         {"PNP0C33", 0},
  34         {"", 0},
  35 };
  36 MODULE_DEVICE_TABLE(acpi, acpi_hed_ids);
  37
  38 static acpi_handle hed_handle;
  39
  40 static BLOCKING_NOTIFIER_HEAD(acpi_hed_notify_list);
  41
  42 int register_acpi_hed_notifier(struct notifier_block *nb)
  43 {
  44         return blocking_notifier_chain_register(&acpi_hed_notify_list, nb);
  45 }
  46 EXPORT_SYMBOL_GPL(register_acpi_hed_notifier);
  47
  48 void unregister_acpi_hed_notifier(struct notifier_block *nb)
  49 {
  50         blocking_notifier_chain_unregister(&acpi_hed_notify_list, nb);
  51 }
  52 EXPORT_SYMBOL_GPL(unregister_acpi_hed_notifier);
  53
  54 /*
  55  * SCI to report hardware error is forwarded to the listeners of HED,
  56  * it is used by HEST Generic Hardware Error Source with notify type
  57  * SCI.
  58  */
  59 static void acpi_hed_notify(struct acpi_device *device, u32 event)
  60 {
  61         blocking_notifier_call_chain(&acpi_hed_notify_list, 0, NULL);
  62 }
  63
  64 static int __devinit acpi_hed_add(struct acpi_device *device)
  65 {
  66         /* Only one hardware error device */
  67         if (hed_handle)
  68                 return -EINVAL;
  69         hed_handle = device->handle;
  70         return 0;
  71 }
  72
  73 static int __devexit acpi_hed_remove(struct acpi_device *device, int type)
  74 {
  75         hed_handle = NULL;
  76         return 0;
  77 }
  78
  79 static struct acpi_driver acpi_hed_driver = {
  80         .name = "hardware_error_device",
  81         .class = "hardware_error",
  82         .ids = acpi_hed_ids,
  83         .ops = {
  84                 .add = acpi_hed_add,
  85                 .remove = acpi_hed_remove,
  86                 .notify = acpi_hed_notify,
  87         },
  88 };
  89
  90 static int __init acpi_hed_init(void)
  91 {
  92         if (acpi_disabled)
  93                 return -ENODEV;
  94
  95         if (acpi_bus_register_driver(&acpi_hed_driver) < 0)
  96                 return -ENODEV;
  97
  98         return 0;
  99 }
 100
 101 static void __exit acpi_hed_exit(void)
 102 {
 103         acpi_bus_unregister_driver(&acpi_hed_driver);
 104 }
 105
 106 module_init(acpi_hed_init);
 107 module_exit(acpi_hed_exit);
 108
 109 ACPI_MODULE_NAME("hed");
 110 MODULE_AUTHOR("Huang Ying");
 111 MODULE_DESCRIPTION("ACPI Hardware Error Device Driver");
 112 MODULE_LICENSE("GPL");