Re: [PATCH v12] platform/x86: add lenovo WMI camera button driver

[Hans de Goede]

Hi,

On 3/28/24 12:35 AM, Kuppuswamy Sathyanarayanan wrote:
> 
> On 3/27/24 1:27 AM, Ai Chao wrote:
>> Add lenovo WMI camera button driver to support camera button.
>> The Camera button is a GPIO device. This driver receives ACPI notifyi
> 
> /s/notifyi/notification
> 
>> when the camera button is switched on/off. This driver is used in
>> Lenovo A70, it is a Computer integrated machine.
>>
>> Signed-off-by: Ai Chao <aichao@xxxxxxxxxx>
>> ---
>> v12: Remove useless parentheses and unneeded blank line.
>> v11: Remove input_unregister_device.
>> v10: Add lenovo_wmi_remove and mutex_destroy.
>> v9: Add mutex for wmi notify.
>> v8: Dev_deb convert to dev_err.
>> v7: Add dev_dbg and remove unused dev in struct.
>> v6: Modify SW_CAMERA_LENS_COVER to KEY_CAMERA_ACCESS_ENABLE/KEY_CAMERA_ACCESS_DISABLE.
>> v5: Remove camera button groups, modify KEY_CAMERA to SW_CAMERA_LENS_COVER.
>> v4: Remove lenovo_wmi_input_setup, move camera_mode into struct lenovo_wmi_priv.
>> v3: Remove lenovo_wmi_remove function.
>> v2: Adjust GPL v2 to GPL, adjust sprintf to sysfs_emit.
>>
>>  drivers/platform/x86/Kconfig             |  12 +++
>>  drivers/platform/x86/Makefile            |   1 +
>>  drivers/platform/x86/lenovo-wmi-camera.c | 127 +++++++++++++++++++++++
>>  3 files changed, 140 insertions(+)
>>  create mode 100644 drivers/platform/x86/lenovo-wmi-camera.c
>>
>> diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
>> index 7e9251fc3341..b8c806506423 100644
>> --- a/drivers/platform/x86/Kconfig
>> +++ b/drivers/platform/x86/Kconfig
>> @@ -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 notify when the
> 
> /s/notify/notification

Thank you. Since I already merged v12 I've squashed a fix for this
into the patch/commit in my review-hans branch.

Regards,

Hans




> 
>> +	  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
>> diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
>> index 1de432e8861e..217e94d7c877 100644
>> --- a/drivers/platform/x86/Makefile
>> +++ b/drivers/platform/x86/Makefile
>> @@ -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/
>> diff --git a/drivers/platform/x86/lenovo-wmi-camera.c b/drivers/platform/x86/lenovo-wmi-camera.c
>> new file mode 100644
>> index 000000000000..0c0bedaf7407
>> --- /dev/null
>> +++ b/drivers/platform/x86/lenovo-wmi-camera.c
>> @@ -0,0 +1,127 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Lenovo WMI Camera Button Driver
>> + *
>> + * Author: Ai Chao <aichao@xxxxxxxxxx>
>> + * 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@xxxxxxxxxx>");
>> +MODULE_DESCRIPTION("Lenovo WMI Camera Button Driver");
>> +MODULE_LICENSE("GPL");
>