Am 05.03.24 um 15:48 schrieb Thomas Weißschuh:
On Tue, Mar 05, 2024 at 08:13:15PM +0800, Ai Chao wrote:
Add lenovo generic wmi driver to support camera button.
The Camera button is a GPIO device. This driver receives ACPI notifyi
when the button pressed.
the button *is* pressed.
The subject does not mention that it is only about te camera button.
I would be interested on which devices this driver was tested and is
expected to work with.
Signed-off-by: Ai Chao <aichao@xxxxxxxxxx>
---
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 | 118 +++++++++++++++++++++++
3 files changed, 131 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..079f5aa5910c 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
+ button pressed.
+
+ 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..77084266829c
--- /dev/null
+++ b/drivers/platform/x86/lenovo-wmi-camera.c
@@ -0,0 +1,118 @@
+// 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/wmi.h>
+
+#define WMI_LENOVO_CAMERABUTTON_EVENT_GUID "50C76F1F-D8E4-D895-0A3D-62F4EA400013"
+
+struct lenovo_wmi_priv {
+ struct input_dev *idev;
+ struct device *dev;
+ u8 camera_mode;
+};
+
+enum {
+ CAMERA_BUTTON_PRESSED = 1,
+};
+
+static ssize_t camerabutton_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct lenovo_wmi_priv *priv = dev_get_drvdata(dev);
+
+ return sysfs_emit(buf, "%u\n", priv->camera_mode);
+}
+DEVICE_ATTR_RO(camerabutton);
+
+static struct attribute *lenovo_wmi_attrs[] = {
+ &dev_attr_camerabutton.attr,
+ NULL,
No trailing comma after sentinel elements.
+};
+
+static const struct attribute_group lenovo_wmi_group = {
+ .attrs = lenovo_wmi_attrs,
+};
+
+const struct attribute_group *lenovo_wmi_groups[] = {
+ &lenovo_wmi_group,
+ NULL,
Also no trailing comma.
+};
+
+static void lenovo_wmi_notify(struct wmi_device *wdev, union acpi_object *obj)
+{
+ struct lenovo_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
+
+ if (obj->type == ACPI_TYPE_BUFFER &&
+ obj->buffer.pointer[0] <= CAMERA_BUTTON_PRESSED) {
+ /* Camera mode:
+ * 0 camera close
+ * 1 camera open
+ */
+ priv->camera_mode = obj->buffer.pointer[0];
This looks similar to a switch.
Would it be more useful for the user to report a standard switch instead
of a key event which needs to be correlated with the sysfs file?
I agree, maybe SW_CAMERA_LENS_COVER might be the right thing to use here,
if those camera states (open/closed) are meant to symbolize camera shutter states.
In such a case the initial switch state has to be retrieved, or else the input device
cannot be registered until the first event is received (similar how the hp-wmi driver
handles SW_CAMERA_LENS_COVER events).
Ai Chao, can you tell us if those two camera states are meant to act like a switch (camera switched off,
camera switched on) or meant to act like a key (camera button pressed, camera button released)?
+
+ input_report_key(priv->idev, KEY_CAMERA, 1);
+ input_sync(priv->idev);
+ input_report_key(priv->idev, KEY_CAMERA, 0);
+ input_sync(priv->idev);
+ } else {
+ dev_dbg(&wdev->dev, "Bad response type %d\n", obj->type);
+ }
+}
+
+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);
+
+ 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;
+ set_bit(EV_KEY, priv->idev->evbit);
+ set_bit(KEY_CAMERA, priv->idev->keybit);
input_set_capability()?
+
+ return input_register_device(priv->idev);
+}
+
+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",
+ .dev_groups = lenovo_wmi_groups,
+ .probe_type = PROBE_PREFER_ASYNCHRONOUS,
+ },
+ .id_table = lenovo_wmi_id_table,
+ .no_singleton = false,
The correct setting in this case would be ".no_singleton = true",
since camera_mode now lives inside struct lenovo_wmi_priv.
Thanks,
Armin Wolf
+ .probe = lenovo_wmi_probe,
+ .notify = lenovo_wmi_notify,
+};
+
+module_wmi_driver(lenovo_wmi_driver);
+
+MODULE_DEVICE_TABLE(wmi, lenovo_wmi_id_table);
+MODULE_AUTHOR("Ai Chao <aichao@xxxxxxxxxx>");
+MODULE_DESCRIPTION("Lenovo Generic WMI Driver");
+MODULE_LICENSE("GPL");
--
2.25.1
