xref: /openbmc/linux/drivers/acpi/hed.c (revision 95e9fd10)
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");
113