Dell travaille sur des pilotes de « boutons de confidentialité » physiques pour désactiver le microphone et la caméra sur Linux

Ils seront livrés avec ses ordinateurs en 2021

Dès l’année prochaine, Dell va fournir des « boutons de confidentialité » matériels pour désactiver la prise en charge du microphone et de la caméra. En vue de la mise sur le marché d'autres ordinateurs portables Dell dotés de ces boutons, un pilote de confidentialité Dell est en cours de préparation pour le noyau Linux.

Ces nouveaux boutons de confidentialité Dell sont essentiellement des interrupteurs d'arrêt matériels pour le flux audio du microphone et vidéo de la caméra. Le pilote de confidentialité Dell envoyé mardi par Perry Yuan (Software Principal Engineer chez Dell) aux responsables du noyau Linux consiste à manipuler les voyants appropriés et à suivre l'état des commandes matérielles, tandis que le basculement (switch) réel du support audio / vidéo est géré par le matériel.

Dans sa forme actuelle, le pilote de confidentialité Dell prend en charge la caméra et le microphone, mais le patch note également un bit "PRIVACY_SCREEN_STATUS". Vraisemblablement, Dell a l’intention d’étendre ce pilote de confidentialité à la gestion d’un filtre de confidentialité (il s’agit d’une protection qui se place devant un écran afin de restreindre la vision des données affichées de part et d’autre de l’axe de vision), ce qui n'est pas sans rappeler le PrivacyGuard de Lenovo et le code pour le filtre de confidentialité sur lequel Google travaille avec les Chromebooks Intel.


Perry Yuan indique dans son courriel : « Ajout de la prise en charge du pilote de confidentialité Dell pour la conception de confidentialité matérielle des unités Dell, qui protège la confidentialité des utilisateurs de l'audio et de la caméra à partir du hardware. Une fois le mode de confidentialité audio ou caméra activé, aucune application ne recevra de flux audio ou vidéo. Lorsque l'utilisateur appuie sur la touche de raccourci ctrl + F4, le mode de confidentialité audio est activé et la touche de raccourci de désactivation de la caméra est ctrl + F9 ».

Voici le code envoyé par les ingénieurs Dell :

[CODE=C] drivers/platform/x86/Kconfig | 12 ++
drivers/platform/x86/Makefile | 4 +-
drivers/platform/x86/dell-laptop.c | 41 ++--
drivers/platform/x86/dell-privacy-acpi.c | 139 ++++++++++++
drivers/platform/x86/dell-privacy-wmi.c | 259 +++++++++++++++++++++++
drivers/platform/x86/dell-privacy-wmi.h | 23 ++
drivers/platform/x86/dell-wmi.c | 90 ++++----
7 files changed, 513 insertions(+), 55 deletions(-)
create mode 100644 drivers/platform/x86/dell-privacy-acpi.c
create mode 100644 drivers/platform/x86/dell-privacy-wmi.c
create mode 100644 drivers/platform/x86/dell-privacy-wmi.h

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 40219bba6801..0cb6bf5a9565 100644
a/drivers/platform/x86/Kconfig
b/drivers/platform/x86/Kconfig
@@ -454,6 +454,18 @@ config DELL_WMI_LED
This adds support for the Latitude 2100 and similar
notebooks that have an external LED.

config DELL_PRIVACY
tristate "Dell Hardware Privacy Support"
depends on ACPI
depends on ACPI_WMI
depends on INPUT
depends on DELL_LAPTOP
select DELL_WMI
help
This driver provides a driver to support messaging related to the
privacy button presses on applicable Dell laptops from 2021 and
newer.

config AMILO_RFKILL
tristate "Fujitsu-Siemens Amilo rfkill support"
depends on RFKILL
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 5f823f7eff45..111f7215db2f 100644
a/drivers/platform/x86/Makefile
b/drivers/platform/x86/Makefile
@@ -47,7 +47,9 @@ obj-$(CONFIG_DELL_WMI) += dell-wmi.o
obj-$(CONFIG_DELL_WMI_DESCRIPTOR) += dell-wmi-descriptor.o
obj-$(CONFIG_DELL_WMI_AIO) += dell-wmi-aio.o
obj-$(CONFIG_DELL_WMI_LED) += dell-wmi-led.o

obj-$(CONFIG_DELL_PRIVACY) += dell-privacy.o
dell-privacy-objs := dell-privacy-wmi.o \
dell-privacy-acpi.o
# Fujitsu
obj-$(CONFIG_AMILO_RFKILL) += amilo-rfkill.o
obj-$(CONFIG_FUJITSU_LAPTOP) += fujitsu-laptop.o
diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
index 5e9c2296931c..12b91de09356 100644
a/drivers/platform/x86/dell-laptop.c
b/drivers/platform/x86/dell-laptop.c
@@ -30,6 +30,7 @@
#include <acpi/video.h>
#include "dell-rbtn.h"
#include "dell-smbios.h"
+#include "dell-privacy-wmi.h"

struct quirk_entry {
bool touchpad_led;
@@ -90,6 +91,7 @@ static struct rfkill *wifi_rfkill;
static struct rfkill *bluetooth_rfkill;
static struct rfkill *wwan_rfkill;
static bool force_rfkill;
+static bool privacy_valid;

module_param(force_rfkill, bool, 0444);
MODULE_PARM_DESC(force_rfkill, "enable rfkill on non whitelisted models");
@@ -2202,20 +2204,25 @@ static int __init dell_init(void)
debugfs_create_file("rfkill", 0444, dell_laptop_dir, NULL,
&dell_debugfs_fops);

- dell_laptop_register_notifier(&dell_laptop_notifier);
-
- if (dell_smbios_find_token(GLOBAL_MIC_MUTE_DISABLE) &&
- dell_smbios_find_token(GLOBAL_MIC_MUTE_ENABLE)) {
- micmute_led_cdev.brightness = ledtrig_audio_get(LED_AUDIO_MICMUTE);
- ret = led_classdev_register(&platform_device->dev, &micmute_led_cdev);
- if (ret < 0)
- goto fail_led;
- }
-
- if (acpi_video_get_backlight_type() != acpi_backlight_vendor)
- return 0;
-
- token = dell_smbios_find_token(BRIGHTNESS_TOKEN);
+ dell_laptop_register_notifier(&dell_laptop_notifier);
+
+ if (dell_smbios_find_token(GLOBAL_MIC_MUTE_DISABLE) &&
+ dell_smbios_find_token(GLOBAL_MIC_MUTE_ENABLE)) {
+#if IS_ENABLED(CONFIG_DELL_PRIVACY)
+ privacy_valid = dell_privacy_valid() == -ENODEV;
+#endif
+ if (!privacy_valid) {
+ micmute_led_cdev.brightness = ledtrig_audio_get(LED_AUDIO_MICMUTE);
+ ret = led_classdev_register(&platform_device->dev, &micmute_led_cdev);
+ if (ret < 0)
+ goto fail_led;
+ }
+ }
+
+ if (acpi_video_get_backlight_type() != acpi_backlight_vendor)
+ return 0;
+
+ token = dell_smbios_find_token(BRIGHTNESS_TOKEN);
if (token) {
struct calling_interface_buffer buffer;

@@ -2257,7 +2264,8 @@ static int __init dell_init(void)
fail_get_brightness:
backlight_device_unregister(dell_backlight_device);
fail_backlight:
- led_classdev_unregister(&micmute_led_cdev);
+ if (!privacy_valid)
+ led_classdev_unregister(&micmute_led_cdev);
fail_led:
dell_cleanup_rfkill();
fail_rfkill:
@@ -2278,7 +2286,8 @@ static void __exit dell_exit(void)
touchpad_led_exit();
kbd_led_exit();
backlight_device_unregister(dell_backlight_device);
- led_classdev_unregister(&micmute_led_cdev);
+ if (!privacy_valid)
+ led_classdev_unregister(&micmute_led_cdev);
dell_cleanup_rfkill();
if (platform_device) {
platform_device_unregister(platform_device);
diff --git a/drivers/platform/x86/dell-privacy-acpi.c b/drivers/platform/x86/dell-privacy-acpi.c
new file mode 100644
index 000000000000..516cd99167c3
--- /dev/null
+++ b/drivers/platform/x86/dell-privacy-acpi.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Dell privacy notification driver
+ *
+ * Copyright (C) 2021 Dell Inc. All Rights Reserved.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/sysfs.h>
+#include <linux/types.h>
+#include <linux/wmi.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include "dell-privacy-wmi.h"
+
+#define PRIVACY_PlATFORM_NAME "dell-privacy-acpi"
+#define ACPI_PRIVACY_DEVICE "\\_SB.PC00.LPCB.ECDV"
+#define ACPI_PRIVACY_EC_ACK ACPI_PRIVACY_DEVICE ".ECAK"
+
+static struct platform_device *privacy_acpi_pdev;
+
+struct privacy_acpi_priv {
+ struct device *dev;
+ struct acpi_device *acpi_dev;
+ struct input_dev *input_dev;
+ struct platform_device *platform_device;
+};
+
+static int micmute_led_set(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ acpi_status status;
+
+ status = acpi_evaluate_object(NULL, ACPI_PRIVACY_EC_ACK, NULL, NULL);
+ if (ACPI_FAILURE(status)) {
+ dev_err(led_cdev->dev, "Error setting privacy audio EC ack value: %d\n",status);
+ return -EIO;
+ }
+ return 0;
+}
+
+static struct led_classdev micmute_led_cdev = {
+ .name = "platform::micmute",
+ .max_brightness = 1,
+ .brightness_set_blocking = micmute_led_set,
+ .default_trigger = "audio-micmute",
+};
+
+static int privacy_acpi_remove(struct platform_device *pdev)
+{
+ dev_set_drvdata(&pdev->dev, NULL);
+ return 0;
+}
+
+static int privacy_acpi_probe(struct platform_device *pdev)
+{
+ struct privacy_acpi_priv *privacy;
+ acpi_handle handle;
+ acpi_status status;
+ int err;
+
+ privacy = kzalloc(sizeof(struct privacy_acpi_priv), GFP_KERNEL);
+ if (!privacy)
+ return -ENOMEM;
+
+ privacy->dev = &pdev->dev;
+ privacy->platform_device = pdev;
+ platform_set_drvdata(pdev, privacy);
+ /* Look for software micmute complete notification device */
+ status = acpi_get_handle(ACPI_ROOT_OBJECT,
+ ACPI_PRIVACY_DEVICE,
+ &handle);
+ if (ACPI_FAILURE(status)) {
+ dev_err(privacy->dev, "Unable to find Dell`s EC device %s: %d\n",
+ ACPI_PRIVACY_DEVICE, status);
+ return -ENXIO;
+ }
+
+ micmute_led_cdev.brightness = ledtrig_audio_get(LED_AUDIO_MICMUTE);
+ err = led_classdev_register(&privacy_acpi_pdev->dev, &micmute_led_cdev);
+ if (err < 0)
+ return -EIO;
+
+ return 0;
+}
+
+static const struct acpi_device_id privacy_acpi_device_ids[] = {
+ {"PNP0C09", 0},
+ {"", 0},
+};
+MODULE_DEVICE_TABLE(acpi, privacy_acpi_device_ids);
+
+static struct platform_driver privacy_platform_driver = {
+ .driver = {
+ .name = PRIVACY_PlATFORM_NAME,
+ .acpi_match_table = ACPI_PTR(privacy_acpi_device_ids),
+ },
+ .probe = privacy_acpi_probe,
+ .remove = privacy_acpi_remove,
+};
+
+int privacy_acpi_init(void)
+{
+ int err;
+
+ err = platform_driver_register(&privacy_platform_driver);
+ if (err)
+ return err;
+
+ privacy_acpi_pdev = platform_device_register_simple(
+ PRIVACY_PlATFORM_NAME, -1, NULL, 0);
+ if (IS_ERR(privacy_acpi_pdev)) {
+ err = PTR_ERR(privacy_acpi_pdev);
+ goto err_platform;
+ }
+ return 0;
+
+err_platform:
+ platform_driver_unregister(&privacy_platform_driver);
+ return err;
+}
+
+void privacy_acpi_cleanup(void)
+{
+ platform_driver_unregister(&privacy_platform_driver);
+}
+
+MODULE_AUTHOR("Perry Yuan <perry_yuan@dell.com>");
+MODULE_DESCRIPTION("DELL Privacy ACPI Driver");
+MODULE_LICENSE("GPL");
+
diff --git a/drivers/platform/x86/dell-privacy-wmi.c b/drivers/platform/x86/dell-privacy-wmi.c
new file mode 100644
index 000000000000..6c36b7ec44c6
--- /dev/null
+++ b/drivers/platform/x86/dell-privacy-wmi.c
@@ -0,0 +1,259 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Dell privacy notification driver
+ *
+ * Copyright (C) 2021 Dell Inc. All Rights Reserved.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/acpi.h>
+#include <linux/input.h>
+#include <linux/input/sparse-keymap.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/wmi.h>
+#include "dell-privacy-wmi.h"
+
+#define DELL_PRIVACY_GUID "6932965F-1671-4CEB-B988-D3AB0A901919"
+#define MICROPHONE_STATUS BIT(0)
+#define CAMERA_STATUS BIT(1)
+#define PRIVACY_SCREEN_STATUS BIT(2)
+
+static int privacy_valid = -EPROBE_DEFER;
+static LIST_HEAD(wmi_list);
+static DEFINE_MUTEX(list_mutex);
+
+struct privacy_wmi_data {
+ struct input_dev *input_dev;
+ struct wmi_device *wdev;
+ struct list_head list;
+ u32 features_present;
+ u32 last_status;
+};
+
+/*
+ * Keymap for WMI Privacy events of type 0x0012
+ */
+static const struct key_entry dell_wmi_keymap_type_0012[] = {
+ /* Privacy MIC Mute */
+ { KE_KEY, 0x0001, { KEY_MICMUTE } },
+ /* Privacy Camera Mute */
+ { KE_SW, 0x0002, { SW_CAMERA_LENS_COVER } },
+};
+
+bool dell_privacy_valid(void)
+{
+ bool ret;
+
+ mutex_lock(&list_mutex);
+ ret = wmi_has_guid(DELL_PRIVACY_GUID);
+ if (!ret){
+ return -ENODEV;
+ }
+ ret = privacy_valid;
+ mutex_unlock(&list_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dell_privacy_valid);
+
+void dell_privacy_process_event(int type, int code, int status)
+{
+ struct privacy_wmi_data *priv;
+ const struct key_entry *key;
+
+ mutex_lock(&list_mutex);
+ priv = list_first_entry_or_null(&wmi_list,
+ struct privacy_wmi_data,
+ list);
+ if (priv == NULL) {
+ pr_err("dell privacy priv is NULL\n");
+ goto error;
+ }
+
+ key = sparse_keymap_entry_from_scancode(priv->input_dev, (type << 16)|code);
+ if (!key) {
+ dev_dbg(&priv->wdev->dev, "Unknown key with type 0x%04x and code 0x%04x pressed\n",
+ type, code);
+ goto error;
+ }
+
+ switch (code) {
+ case DELL_PRIVACY_TYPE_AUDIO: /* Mic mute */
+ priv->last_status = status;
+ sparse_keymap_report_entry(priv->input_dev, key, 1, true);
+ break;
+ case DELL_PRIVACY_TYPE_CAMERA: /* Camera mute */
+ priv->last_status = status;
+ sparse_keymap_report_entry(priv->input_dev, key, 1, true);
+ break;
+ default:
+ dev_dbg(&priv->wdev->dev, "unknown event type %u /%u",
+ type, code);
+ }
+error:
+ mutex_unlock(&list_mutex);
+ return;
+}
+EXPORT_SYMBOL_GPL(dell_privacy_process_event);
+
+static int get_current_status(struct wmi_device *wdev)
+{
+ struct privacy_wmi_data *priv = dev_get_drvdata(&wdev->dev);
+ union acpi_object *obj_present;
+ union acpi_object *obj_current;
+ int ret = 0;
+
+ if (priv == NULL) {
+ pr_err("dell privacy priv is NULL\n");
+ return -EINVAL;
+ }
+ /* get devices supported */
+ obj_present = wmidev_block_query(wdev, 0);
+ if (obj_present->type != ACPI_TYPE_INTEGER) {
+ ret = -EIO;
+ goto present_free;
+ }
+ priv->features_present = obj_present->integer.value;
+
+ /* get current state */
+ obj_current = wmidev_block_query(wdev, 1);
+ if (obj_current->type != ACPI_TYPE_INTEGER) {
+ ret = -EIO;
+ goto current_free;
+ }
+ priv->last_status = obj_current->integer.value;
current_free:
kfree(obj_current);
present_free:
kfree(obj_present);
return ret;
}

static int dell_privacy_wmi_probe(struct wmi_device *wdev, const void *context)
{
struct privacy_wmi_data *priv;
struct key_entry *keymap;
int ret, i, pos = 0;

priv = devm_kzalloc(&wdev->dev, sizeof(struct privacy_wmi_data),
GFP_KERNEL);
if (!priv)
return -ENOMEM;

/* create evdev passing interface */
priv->input_dev = devm_input_allocate_device(&wdev->dev);
if (!priv->input_dev)
return -ENOMEM;

__set_bit(EV_KEY, priv->input_dev->evbit);
__set_bit(KEY_MICMUTE, priv->input_dev->keybit);
__set_bit(EV_MSC, priv->input_dev->evbit);
__set_bit(MSC_SCAN, priv->input_dev->mscbit);
keymap = kcalloc(
ARRAY_SIZE(dell_wmi_keymap_type_0012) +
1,
sizeof(struct key_entry), GFP_KERNEL);
if (!keymap) {
ret = -ENOMEM;
goto err_free[/]...