Am 20.03.24 um 09:17 schrieb Ai Chao:
Add lenovo generic wmi driver to support camera button. The Camera button is a GPIO device. This driver receives ACPI notifyi 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> --- 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 | 123 +++++++++++++++++++++++ 3 files changed, 136 insertions(+) create mode 100644 drivers/platform/x86/lenovo-wmi-camera.c diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig index bdd302274b9a..9506a455b547 100644 --- a/drivers/platform/x86/Kconfig +++ b/drivers/platform/x86/Kconfig @@ -1001,6 +1001,18 @@ 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 + 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..4b1bd81cc581 --- /dev/null +++ b/drivers/platform/x86/lenovo-wmi-camera.c @@ -0,0 +1,123 @@ +// 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/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; + + priv = devm_kzalloc(&wdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + dev_set_drvdata(&wdev->dev, priv); + + mutex_init(&priv->notify_lock); + priv->idev = devm_input_allocate_device(&wdev->dev); + if (!priv->idev) { + mutex_destroy(&priv->notify_lock); + 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); + + return input_register_device(priv->idev); +} + +static void lenovo_wmi_remove(struct wmi_device *wdev) +{ + struct lenovo_wmi_priv *priv = dev_get_drvdata(&wdev->dev); + + mutex_destroy(&priv->notify_lock); + input_unregister_device(priv->idev);
Hi, input_unregister_device() is not needed because of devm_input_allocate_device(), and still mutex_destroy() is not called when input_device_register() fails. Maybe you can just call mutex_init() after calling input_device_register() (after doing the necessary error handling), like this: ret = input_register_device(priv->idev); if (ret < 0) return ret; mutex_init(&priv->notify_lock); return 0; This should work because the notify handler (which is the only user of this mutex) can only run after lenovo_wmi_probe() returns. In lenovo_wmi_remove(), you then just need to call mutex_destroy(). Thanks, Armin Wolf
+} + +static const struct wmi_device_id lenovo_wmi_id_table[] = { + { .guid_string = WMI_LENOVO_CAMERABUTTON_EVENT_GUID }, + { } +}; + +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_DEVICE_TABLE(wmi, lenovo_wmi_id_table); +MODULE_AUTHOR("Ai Chao <aichao@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Lenovo WMI Camera Button Driver"); +MODULE_LICENSE("GPL");