xref: /linux/drivers/acpi/hed.c (revision 69050f8d6d075dc01af7a5f2f550a8067510366f)
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 <linux/platform_device.h>
17 #include <acpi/hed.h>
18 
19 static const struct acpi_device_id acpi_hed_ids[] = {
20 	{"PNP0C33", 0},
21 	{"", 0},
22 };
23 MODULE_DEVICE_TABLE(acpi, acpi_hed_ids);
24 
25 static acpi_handle hed_handle;
26 
27 static BLOCKING_NOTIFIER_HEAD(acpi_hed_notify_list);
28 
29 int register_acpi_hed_notifier(struct notifier_block *nb)
30 {
31 	return blocking_notifier_chain_register(&acpi_hed_notify_list, nb);
32 }
33 EXPORT_SYMBOL_GPL(register_acpi_hed_notifier);
34 
35 void unregister_acpi_hed_notifier(struct notifier_block *nb)
36 {
37 	blocking_notifier_chain_unregister(&acpi_hed_notify_list, nb);
38 }
39 EXPORT_SYMBOL_GPL(unregister_acpi_hed_notifier);
40 
41 /*
42  * SCI to report hardware error is forwarded to the listeners of HED,
43  * it is used by HEST Generic Hardware Error Source with notify type
44  * SCI.
45  */
46 static void acpi_hed_notify(acpi_handle handle, u32 event, void *data)
47 {
48 	blocking_notifier_call_chain(&acpi_hed_notify_list, 0, NULL);
49 }
50 
51 static int acpi_hed_probe(struct platform_device *pdev)
52 {
53 	struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
54 	int err;
55 
56 	/* Only one hardware error device */
57 	if (hed_handle)
58 		return -EINVAL;
59 	hed_handle = device->handle;
60 
61 	err = acpi_dev_install_notify_handler(device, ACPI_DEVICE_NOTIFY,
62 					      acpi_hed_notify, device);
63 	if (err)
64 		hed_handle = NULL;
65 
66 	return err;
67 }
68 
69 static void acpi_hed_remove(struct platform_device *pdev)
70 {
71 	struct acpi_device *device = ACPI_COMPANION(&pdev->dev);
72 
73 	acpi_dev_remove_notify_handler(device, ACPI_DEVICE_NOTIFY,
74 				       acpi_hed_notify);
75 	hed_handle = NULL;
76 }
77 
78 static struct platform_driver acpi_hed_driver = {
79 	.probe = acpi_hed_probe,
80 	.remove = acpi_hed_remove,
81 	.driver = {
82 		.name = "acpi-hardware-error-device",
83 		.acpi_match_table = acpi_hed_ids,
84 	},
85 };
86 
87 static int __init acpi_hed_driver_init(void)
88 {
89 	return platform_driver_register(&acpi_hed_driver);
90 }
91 subsys_initcall(acpi_hed_driver_init);
92 
93 MODULE_AUTHOR("Huang Ying");
94 MODULE_DESCRIPTION("ACPI Hardware Error Device Driver");
95 MODULE_LICENSE("GPL");
96