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platform/x86: amd-pmc: Move to later in the suspend process
[linux.git] / drivers / gpu / drm / drm_privacy_screen_x86.c
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright (C) 2020 Red Hat, Inc.
4  *
5  * Authors:
6  * Hans de Goede <[email protected]>
7  */
8
9 #include <linux/acpi.h>
10 #include <drm/drm_privacy_screen_machine.h>
11
12 #ifdef CONFIG_X86
13 static struct drm_privacy_screen_lookup arch_lookup;
14
15 struct arch_init_data {
16         struct drm_privacy_screen_lookup lookup;
17         bool (*detect)(void);
18 };
19
20 #if IS_ENABLED(CONFIG_THINKPAD_ACPI)
21 static acpi_status __init acpi_set_handle(acpi_handle handle, u32 level,
22                                           void *context, void **return_value)
23 {
24         *(acpi_handle *)return_value = handle;
25         return AE_CTRL_TERMINATE;
26 }
27
28 static bool __init detect_thinkpad_privacy_screen(void)
29 {
30         union acpi_object obj = { .type = ACPI_TYPE_INTEGER };
31         struct acpi_object_list args = { .count = 1, .pointer = &obj, };
32         acpi_handle ec_handle = NULL;
33         unsigned long long output;
34         acpi_status status;
35
36         /* Get embedded-controller handle */
37         status = acpi_get_devices("PNP0C09", acpi_set_handle, NULL, &ec_handle);
38         if (ACPI_FAILURE(status) || !ec_handle)
39                 return false;
40
41         /* And call the privacy-screen get-status method */
42         status = acpi_evaluate_integer(ec_handle, "HKEY.GSSS", &args, &output);
43         if (ACPI_FAILURE(status))
44                 return false;
45
46         return (output & 0x10000) ? true : false;
47 }
48 #endif
49
50 static const struct arch_init_data arch_init_data[] __initconst = {
51 #if IS_ENABLED(CONFIG_THINKPAD_ACPI)
52         {
53                 .lookup = {
54                         .dev_id = NULL,
55                         .con_id = NULL,
56                         .provider = "privacy_screen-thinkpad_acpi",
57                 },
58                 .detect = detect_thinkpad_privacy_screen,
59         },
60 #endif
61 };
62
63 void __init drm_privacy_screen_lookup_init(void)
64 {
65         int i;
66
67         for (i = 0; i < ARRAY_SIZE(arch_init_data); i++) {
68                 if (!arch_init_data[i].detect())
69                         continue;
70
71                 pr_info("Found '%s' privacy-screen provider\n",
72                         arch_init_data[i].lookup.provider);
73
74                 /* Make a copy because arch_init_data is __initconst */
75                 arch_lookup = arch_init_data[i].lookup;
76                 drm_privacy_screen_lookup_add(&arch_lookup);
77                 break;
78         }
79 }
80
81 void drm_privacy_screen_lookup_exit(void)
82 {
83         if (arch_lookup.provider)
84                 drm_privacy_screen_lookup_remove(&arch_lookup);
85 }
86 #endif /* ifdef CONFIG_X86 */
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