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
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/acpi.h>
  24 #include <acpi/hed.h>
  25
  26 static const struct acpi_device_id acpi_hed_ids[] = {
  27         {"PNP0C33", 0},
  28         {"", 0},
  29 };
  30 MODULE_DEVICE_TABLE(acpi, acpi_hed_ids);
  31
  32 static acpi_handle hed_handle;
  33
  34 static BLOCKING_NOTIFIER_HEAD(acpi_hed_notify_list);
  35
  36 int register_acpi_hed_notifier(struct notifier_block *nb)
  37 {
  38         return blocking_notifier_chain_register(&acpi_hed_notify_list, nb);
  39 }
  40 EXPORT_SYMBOL_GPL(register_acpi_hed_notifier);
  41
  42 void unregister_acpi_hed_notifier(struct notifier_block *nb)
  43 {
  44         blocking_notifier_chain_unregister(&acpi_hed_notify_list, nb);
  45 }
  46 EXPORT_SYMBOL_GPL(unregister_acpi_hed_notifier);
  47
  48 /*
  49  * SCI to report hardware error is forwarded to the listeners of HED,
  50  * it is used by HEST Generic Hardware Error Source with notify type
  51  * SCI.
  52  */
  53 static void acpi_hed_notify(struct acpi_device *device, u32 event)
  54 {
  55         blocking_notifier_call_chain(&acpi_hed_notify_list, 0, NULL);
  56 }
  57
  58 static int acpi_hed_add(struct acpi_device *device)
  59 {
  60         /* Only one hardware error device */
  61         if (hed_handle)
  62                 return -EINVAL;
  63         hed_handle = device->handle;
  64         return 0;
  65 }
  66
  67 static int acpi_hed_remove(struct acpi_device *device)
  68 {
  69         hed_handle = NULL;
  70         return 0;
  71 }
  72
  73 static struct acpi_driver acpi_hed_driver = {
  74         .name = "hardware_error_device",
  75         .class = "hardware_error",
  76         .ids = acpi_hed_ids,
  77         .ops = {
  78                 .add = acpi_hed_add,
  79                 .remove = acpi_hed_remove,
  80                 .notify = acpi_hed_notify,
  81         },
  82 };
  83 module_acpi_driver(acpi_hed_driver);
  84
  85 ACPI_MODULE_NAME("hed");
  86 MODULE_AUTHOR("Huang Ying");
  87 MODULE_DESCRIPTION("ACPI Hardware Error Device Driver");
  88 MODULE_LICENSE("GPL");