Commit befe5404 authored by Hans de Goede's avatar Hans de Goede
Browse files

drm/privacy-screen: Add X86 specific arch init code 



Add X86 specific arch init code, which fills the privacy-screen lookup
table by checking for various vendor specific ACPI interfaces for
controlling the privacy-screen.

This initial version only checks for the Lenovo Thinkpad specific ACPI
methods for privacy-screen control.

Reviewed-by: default avatarEmil Velikov <emil.l.velikov@gmail.com>
Reviewed-by: default avatarLyude Paul <lyude@redhat.com>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211005202322.700909-4-hdegoede@redhat.com
parent a1a98689

drivers/gpu/drm/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -32,7 +32,7 @@ drm-$(CONFIG_OF) += drm_of.o 
drm-$(CONFIG_PCI) += drm_pci.o

drm-$(CONFIG_DEBUG_FS) += drm_debugfs.o drm_debugfs_crc.o

drm-$(CONFIG_DRM_LOAD_EDID_FIRMWARE) += drm_edid_load.o

drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o

drm-$(CONFIG_DRM_PRIVACY_SCREEN) += drm_privacy_screen.o drm_privacy_screen_x86.o



obj-$(CONFIG_DRM_DP_AUX_BUS) += drm_dp_aux_bus.o

drivers/gpu/drm/drm_privacy_screen_x86.c

0 → 100644
+86 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: MIT

/*

 * Copyright (C) 2020 Red Hat, Inc.

 *

 * Authors:

 * Hans de Goede <hdegoede@redhat.com>

 */



#include <linux/acpi.h>

#include <drm/drm_privacy_screen_machine.h>



#ifdef CONFIG_X86

static struct drm_privacy_screen_lookup arch_lookup;



struct arch_init_data {

	struct drm_privacy_screen_lookup lookup;

	bool (*detect)(void);

};



#if IS_ENABLED(CONFIG_THINKPAD_ACPI)

static acpi_status __init acpi_set_handle(acpi_handle handle, u32 level,

					  void *context, void **return_value)

{

	*(acpi_handle *)return_value = handle;

	return AE_CTRL_TERMINATE;

}



static bool __init detect_thinkpad_privacy_screen(void)

{

	union acpi_object obj = { .type = ACPI_TYPE_INTEGER };

	struct acpi_object_list args = { .count = 1, .pointer = &obj, };

	acpi_handle ec_handle = NULL;

	unsigned long long output;

	acpi_status status;



	/* Get embedded-controller handle */

	status = acpi_get_devices("PNP0C09", acpi_set_handle, NULL, &ec_handle);

	if (ACPI_FAILURE(status) || !ec_handle)

		return false;



	/* And call the privacy-screen get-status method */

	status = acpi_evaluate_integer(ec_handle, "HKEY.GSSS", &args, &output);

	if (ACPI_FAILURE(status))

		return false;



	return (output & 0x10000) ? true : false;

}

#endif



static const struct arch_init_data arch_init_data[] __initconst = {

#if IS_ENABLED(CONFIG_THINKPAD_ACPI)

	{

		.lookup = {

			.dev_id = NULL,

			.con_id = NULL,

			.provider = "privacy_screen-thinkpad_acpi",

		},

		.detect = detect_thinkpad_privacy_screen,

	},

#endif

};



void __init drm_privacy_screen_lookup_init(void)

{

	int i;



	for (i = 0; i < ARRAY_SIZE(arch_init_data); i++) {

		if (!arch_init_data[i].detect())

			continue;



		pr_info("Found '%s' privacy-screen provider\n",

			arch_init_data[i].lookup.provider);



		/* Make a copy because arch_init_data is __initconst */

		arch_lookup = arch_init_data[i].lookup;

		drm_privacy_screen_lookup_add(&arch_lookup);

		break;

	}

}



void drm_privacy_screen_lookup_exit(void)

{

	if (arch_lookup.provider)

		drm_privacy_screen_lookup_remove(&arch_lookup);

}

#endif /* ifdef CONFIG_X86 */

include/drm/drm_privacy_screen_machine.h

+5 −0
Original line number Diff line number Diff line
@@ -31,11 +31,16 @@ struct drm_privacy_screen_lookup { 
void drm_privacy_screen_lookup_add(struct drm_privacy_screen_lookup *lookup);

void drm_privacy_screen_lookup_remove(struct drm_privacy_screen_lookup *lookup);



#if IS_ENABLED(CONFIG_DRM_PRIVACY_SCREEN) && IS_ENABLED(CONFIG_X86)

void drm_privacy_screen_lookup_init(void);

void drm_privacy_screen_lookup_exit(void);

#else

static inline void drm_privacy_screen_lookup_init(void)

{

}

static inline void drm_privacy_screen_lookup_exit(void)

{

}

#endif



#endif