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1// SPDX-License-Identifier: MIT2/*3 * Copyright (C) 2020 Red Hat, Inc.4 *5 * Authors:6 * Hans de Goede <hdegoede@redhat.com>7 */8 9#include <linux/acpi.h>10#include <drm/drm_privacy_screen_machine.h>11 12#ifdef CONFIG_X8613static struct drm_privacy_screen_lookup arch_lookup;14 15struct arch_init_data {16 struct drm_privacy_screen_lookup lookup;17 bool (*detect)(void);18};19 20#if IS_ENABLED(CONFIG_THINKPAD_ACPI)21static 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 28static 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 if (acpi_disabled)37 return false;38 39 /* Get embedded-controller handle */40 status = acpi_get_devices("PNP0C09", acpi_set_handle, NULL, &ec_handle);41 if (ACPI_FAILURE(status) || !ec_handle)42 return false;43 44 /* And call the privacy-screen get-status method */45 status = acpi_evaluate_integer(ec_handle, "HKEY.GSSS", &args, &output);46 if (ACPI_FAILURE(status))47 return false;48 49 return (output & 0x10000) ? true : false;50}51#endif52 53#if IS_ENABLED(CONFIG_CHROMEOS_PRIVACY_SCREEN)54static bool __init detect_chromeos_privacy_screen(void)55{56 return acpi_dev_present("GOOG0010", NULL, -1);57}58#endif59 60static const struct arch_init_data arch_init_data[] __initconst = {61#if IS_ENABLED(CONFIG_THINKPAD_ACPI)62 {63 .lookup = {64 .dev_id = NULL,65 .con_id = NULL,66 .provider = "privacy_screen-thinkpad_acpi",67 },68 .detect = detect_thinkpad_privacy_screen,69 },70#endif71#if IS_ENABLED(CONFIG_CHROMEOS_PRIVACY_SCREEN)72 {73 .lookup = {74 .dev_id = NULL,75 .con_id = NULL,76 .provider = "privacy_screen-GOOG0010:00",77 },78 .detect = detect_chromeos_privacy_screen,79 },80#endif81};82 83void __init drm_privacy_screen_lookup_init(void)84{85 int i;86 87 for (i = 0; i < ARRAY_SIZE(arch_init_data); i++) {88 if (!arch_init_data[i].detect())89 continue;90 91 pr_info("Found '%s' privacy-screen provider\n",92 arch_init_data[i].lookup.provider);93 94 /* Make a copy because arch_init_data is __initconst */95 arch_lookup = arch_init_data[i].lookup;96 drm_privacy_screen_lookup_add(&arch_lookup);97 break;98 }99}100 101void drm_privacy_screen_lookup_exit(void)102{103 if (arch_lookup.provider)104 drm_privacy_screen_lookup_remove(&arch_lookup);105}106#endif /* ifdef CONFIG_X86 */107