xref: /openbmc/linux/drivers/acpi/hed.c (revision a34a9f1a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ACPI Hardware Error Device (PNP0C33) Driver
4  *
5  * Copyright (C) 2010, Intel Corp.
6  *	Author: Huang Ying <ying.huang@intel.com>
7  *
8  * ACPI Hardware Error Device is used to report some hardware errors
9  * notified via SCI, mainly the corrected errors.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/acpi.h>
16 #include <acpi/hed.h>
17 
18 static const struct acpi_device_id acpi_hed_ids[] = {
19 	{"PNP0C33", 0},
20 	{"", 0},
21 };
22 MODULE_DEVICE_TABLE(acpi, acpi_hed_ids);
23 
24 static acpi_handle hed_handle;
25 
26 static BLOCKING_NOTIFIER_HEAD(acpi_hed_notify_list);
27 
28 int register_acpi_hed_notifier(struct notifier_block *nb)
29 {
30 	return blocking_notifier_chain_register(&acpi_hed_notify_list, nb);
31 }
32 EXPORT_SYMBOL_GPL(register_acpi_hed_notifier);
33 
34 void unregister_acpi_hed_notifier(struct notifier_block *nb)
35 {
36 	blocking_notifier_chain_unregister(&acpi_hed_notify_list, nb);
37 }
38 EXPORT_SYMBOL_GPL(unregister_acpi_hed_notifier);
39 
40 /*
41  * SCI to report hardware error is forwarded to the listeners of HED,
42  * it is used by HEST Generic Hardware Error Source with notify type
43  * SCI.
44  */
45 static void acpi_hed_notify(acpi_handle handle, u32 event, void *data)
46 {
47 	blocking_notifier_call_chain(&acpi_hed_notify_list, 0, NULL);
48 }
49 
50 static int acpi_hed_add(struct acpi_device *device)
51 {
52 	int err;
53 
54 	/* Only one hardware error device */
55 	if (hed_handle)
56 		return -EINVAL;
57 	hed_handle = device->handle;
58 
59 	err = acpi_dev_install_notify_handler(device, ACPI_DEVICE_NOTIFY,
60 					      acpi_hed_notify);
61 	if (err)
62 		hed_handle = NULL;
63 
64 	return err;
65 }
66 
67 static void acpi_hed_remove(struct acpi_device *device)
68 {
69 	acpi_dev_remove_notify_handler(device, ACPI_DEVICE_NOTIFY,
70 				       acpi_hed_notify);
71 	hed_handle = NULL;
72 }
73 
74 static struct acpi_driver acpi_hed_driver = {
75 	.name = "hardware_error_device",
76 	.class = "hardware_error",
77 	.ids = acpi_hed_ids,
78 	.ops = {
79 		.add = acpi_hed_add,
80 		.remove = acpi_hed_remove,
81 	},
82 };
83 module_acpi_driver(acpi_hed_driver);
84 
85 MODULE_AUTHOR("Huang Ying");
86 MODULE_DESCRIPTION("ACPI Hardware Error Device Driver");
87 MODULE_LICENSE("GPL");
88