diff options
Diffstat (limited to 'drivers/platform/x86/lenovo-wmi-camera.c')
| -rw-r--r-- | drivers/platform/x86/lenovo-wmi-camera.c | 127 |
1 files changed, 127 insertions, 0 deletions
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@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"); |