Commit fe7af611 authored by Ai Chao's avatar Ai Chao Committed by Hans de Goede
Browse files

platform/x86: add lenovo WMI camera button driver 



Add lenovo WMI camera button driver to support camera button.
The Camera button is a GPIO device. This driver receives ACPI notifications
when the camera button is switched on/off. This driver is used in
Lenovo A70, it is a Computer integrated machine.

Signed-off-by: default avatarAi Chao <aichao@kylinos.cn>
Link: https://lore.kernel.org/r/20240327082737.336992-1-aichao@kylinos.cn


Reviewed-by: default avatarArmin Wolf <W_Armin@gmx.de>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
parent 3427c443

drivers/platform/x86/Kconfig

+12 −0
Original line number Diff line number Diff line
@@ -996,6 +996,18 @@ config INSPUR_PLATFORM_PROFILE 
	To compile this driver as a module, choose M here: the module

	will be called inspur-platform-profile.



config LENOVO_WMI_CAMERA

	tristate "Lenovo WMI Camera Button driver"

	depends on ACPI_WMI

	depends on INPUT

	help

	  This driver provides support for Lenovo camera button. The Camera

	  button is a GPIO device. This driver receives ACPI notifications when

	  the camera button is switched on/off.



	  To compile this driver as a module, choose M here: the module

	  will be called lenovo-wmi-camera.



source "drivers/platform/x86/x86-android-tablets/Kconfig"



config FW_ATTR_CLASS

drivers/platform/x86/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -66,6 +66,7 @@ obj-$(CONFIG_SENSORS_HDAPS) += hdaps.o 
obj-$(CONFIG_THINKPAD_ACPI)	+= thinkpad_acpi.o

obj-$(CONFIG_THINKPAD_LMI)	+= think-lmi.o

obj-$(CONFIG_YOGABOOK)		+= lenovo-yogabook.o

obj-$(CONFIG_LENOVO_WMI_CAMERA)	+= lenovo-wmi-camera.o



# Intel

obj-y				+= intel/

drivers/platform/x86/lenovo-wmi-camera.c

0 → 100644
+127 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0

/*

 * Lenovo WMI Camera Button Driver

 *

 * Author: Ai Chao <aichao@kylinos.cn>

 * Copyright (C) 2024 KylinSoft Corporation.

 */



#include <linux/acpi.h>

#include <linux/device.h>

#include <linux/input.h>

#include <linux/types.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/wmi.h>



#define WMI_LENOVO_CAMERABUTTON_EVENT_GUID "50C76F1F-D8E4-D895-0A3D-62F4EA400013"



struct lenovo_wmi_priv {

	struct input_dev *idev;

	struct mutex notify_lock;	/* lenovo WMI camera button notify lock */

};



enum {

	SW_CAMERA_OFF	= 0,

	SW_CAMERA_ON	= 1,

};



static void lenovo_wmi_notify(struct wmi_device *wdev, union acpi_object *obj)

{

	struct lenovo_wmi_priv *priv = dev_get_drvdata(&wdev->dev);

	unsigned int keycode;

	u8 camera_mode;



	if (obj->type != ACPI_TYPE_BUFFER) {

		dev_err(&wdev->dev, "Bad response type %u\n", obj->type);

		return;

	}



	if (obj->buffer.length != 1) {

		dev_err(&wdev->dev, "Invalid buffer length %u\n", obj->buffer.length);

		return;

	}



	/*

	 * obj->buffer.pointer[0] is camera mode:

	 *      0 camera close

	 *      1 camera open

	 */

	camera_mode = obj->buffer.pointer[0];

	if (camera_mode > SW_CAMERA_ON) {

		dev_err(&wdev->dev, "Unknown camera mode %u\n", camera_mode);

		return;

	}



	mutex_lock(&priv->notify_lock);



	keycode = camera_mode == SW_CAMERA_ON ?

		   KEY_CAMERA_ACCESS_ENABLE : KEY_CAMERA_ACCESS_DISABLE;

	input_report_key(priv->idev, keycode, 1);

	input_sync(priv->idev);

	input_report_key(priv->idev, keycode, 0);

	input_sync(priv->idev);



	mutex_unlock(&priv->notify_lock);

}



static int lenovo_wmi_probe(struct wmi_device *wdev, const void *context)

{

	struct lenovo_wmi_priv *priv;

	int ret;



	priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL);

	if (!priv)

		return -ENOMEM;



	dev_set_drvdata(&wdev->dev, priv);



	priv->idev = devm_input_allocate_device(&wdev->dev);

	if (!priv->idev)

		return -ENOMEM;



	priv->idev->name = "Lenovo WMI Camera Button";

	priv->idev->phys = "wmi/input0";

	priv->idev->id.bustype = BUS_HOST;

	priv->idev->dev.parent = &wdev->dev;

	input_set_capability(priv->idev, EV_KEY, KEY_CAMERA_ACCESS_ENABLE);

	input_set_capability(priv->idev, EV_KEY, KEY_CAMERA_ACCESS_DISABLE);



	ret = input_register_device(priv->idev);

	if (ret)

		return ret;



	mutex_init(&priv->notify_lock);



	return 0;

}



static void lenovo_wmi_remove(struct wmi_device *wdev)

{

	struct lenovo_wmi_priv *priv = dev_get_drvdata(&wdev->dev);



	mutex_destroy(&priv->notify_lock);

}



static const struct wmi_device_id lenovo_wmi_id_table[] = {

	{ .guid_string = WMI_LENOVO_CAMERABUTTON_EVENT_GUID },

	{  }

};

MODULE_DEVICE_TABLE(wmi, lenovo_wmi_id_table);



static struct wmi_driver lenovo_wmi_driver = {

	.driver = {

		.name = "lenovo-wmi-camera",

		.probe_type = PROBE_PREFER_ASYNCHRONOUS,

	},

	.id_table = lenovo_wmi_id_table,

	.no_singleton = true,

	.probe = lenovo_wmi_probe,

	.notify = lenovo_wmi_notify,

	.remove = lenovo_wmi_remove,

};

module_wmi_driver(lenovo_wmi_driver);



MODULE_AUTHOR("Ai Chao <aichao@kylinos.cn>");

MODULE_DESCRIPTION("Lenovo WMI Camera Button Driver");

MODULE_LICENSE("GPL");