--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/* WMI driver for Lenovo Yoga Book YB1-X90* / -X91* tablets */
+
+#include <linux/acpi.h>
+#include <linux/devm-helpers.h>
+#include <linux/module.h>
+#include <linux/leds.h>
+#include <linux/wmi.h>
+#include <linux/workqueue.h>
+
+#define YB_MBTN_EVENT_GUID "243FEC1D-1963-41C1-8100-06A9D82A94B4"
+#define YB_MBTN_METHOD_GUID "742B0CA1-0B20-404B-9CAA-AEFCABF30CE0"
+
+#define YB_PAD_ENABLE 1
+#define YB_PAD_DISABLE 2
+#define YB_LIGHTUP_BTN 3
+
+#define YB_KBD_BL_DEFAULT 128
+
+/* flags */
+enum {
+ YB_KBD_IS_ON,
+ YB_DIGITIZER_IS_ON,
+ YB_DIGITIZER_MODE,
+ YB_SUSPENDED,
+};
+
+struct yogabook_wmi {
+ struct wmi_device *wdev;
+ struct acpi_device *kbd_adev;
+ struct acpi_device *dig_adev;
+ struct device *kbd_dev;
+ struct device *dig_dev;
+ struct work_struct work;
+ struct led_classdev kbd_bl_led;
+ unsigned long flags;
+ uint8_t brightness;
+};
+
+static int yogabook_wmi_do_action(struct wmi_device *wdev, int action)
+{
+ struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+ struct acpi_buffer input;
+ acpi_status status;
+ u32 dummy_arg = 0;
+
+ dev_dbg(&wdev->dev, "Do action: %d\n", action);
+
+ input.pointer = &dummy_arg;
+ input.length = sizeof(dummy_arg);
+
+ status = wmi_evaluate_method(YB_MBTN_METHOD_GUID, 0, action, &input,
+ &output);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&wdev->dev, "Calling WMI method failure: 0x%x\n",
+ status);
+ return status;
+ }
+
+ kfree(output.pointer);
+
+ return 0;
+}
+
+/*
+ * To control keyboard backlight, call the method KBLC() of the TCS1 ACPI
+ * device (Goodix touchpad acts as virtual sensor keyboard).
+ */
+static int yogabook_wmi_set_kbd_backlight(struct wmi_device *wdev,
+ uint8_t level)
+{
+ struct yogabook_wmi *data = dev_get_drvdata(&wdev->dev);
+ struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL };
+ struct acpi_object_list input;
+ union acpi_object param;
+ acpi_status status;
+
+ if (data->kbd_adev->power.state != ACPI_STATE_D0) {
+ dev_warn(&wdev->dev, "keyboard touchscreen not in D0, cannot set brightness\n");
+ return -ENXIO;
+ }
+
+ dev_dbg(&wdev->dev, "Set KBLC level to %u\n", level);
+
+ input.count = 1;
+ input.pointer = ¶m;
+
+ param.type = ACPI_TYPE_INTEGER;
+ param.integer.value = 255 - level;
+
+ status = acpi_evaluate_object(acpi_device_handle(data->kbd_adev), "KBLC",
+ &input, &output);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&wdev->dev, "Failed to call KBLC method: 0x%x\n", status);
+ return status;
+ }
+
+ kfree(output.pointer);
+ return 0;
+}
+
+static void yogabook_wmi_work(struct work_struct *work)
+{
+ struct yogabook_wmi *data = container_of(work, struct yogabook_wmi, work);
+ struct device *dev = &data->wdev->dev;
+ bool kbd_on, digitizer_on;
+ int r;
+
+ if (test_bit(YB_SUSPENDED, &data->flags))
+ return;
+
+ if (test_bit(YB_DIGITIZER_MODE, &data->flags)) {
+ digitizer_on = true;
+ kbd_on = false;
+ } else {
+ kbd_on = true;
+ digitizer_on = false;
+ }
+
+ if (!kbd_on && test_bit(YB_KBD_IS_ON, &data->flags)) {
+ /*
+ * Must be done before releasing the keyboard touchscreen driver,
+ * so that the keyboard touchscreen dev is still in D0.
+ */
+ yogabook_wmi_set_kbd_backlight(data->wdev, 0);
+ device_release_driver(data->kbd_dev);
+ clear_bit(YB_KBD_IS_ON, &data->flags);
+ }
+
+ if (!digitizer_on && test_bit(YB_DIGITIZER_IS_ON, &data->flags)) {
+ yogabook_wmi_do_action(data->wdev, YB_PAD_DISABLE);
+ device_release_driver(data->dig_dev);
+ clear_bit(YB_DIGITIZER_IS_ON, &data->flags);
+ }
+
+ if (kbd_on && !test_bit(YB_KBD_IS_ON, &data->flags)) {
+ r = device_reprobe(data->kbd_dev);
+ if (r)
+ dev_warn(dev, "Reprobe of keyboard touchscreen failed: %d\n", r);
+
+ yogabook_wmi_set_kbd_backlight(data->wdev, data->brightness);
+ set_bit(YB_KBD_IS_ON, &data->flags);
+ }
+
+ if (digitizer_on && !test_bit(YB_DIGITIZER_IS_ON, &data->flags)) {
+ r = device_reprobe(data->dig_dev);
+ if (r)
+ dev_warn(dev, "Reprobe of digitizer failed: %d\n", r);
+
+ yogabook_wmi_do_action(data->wdev, YB_PAD_ENABLE);
+ set_bit(YB_DIGITIZER_IS_ON, &data->flags);
+ }
+}
+
+static void yogabook_wmi_notify(struct wmi_device *wdev, union acpi_object *dummy)
+{
+ struct yogabook_wmi *data = dev_get_drvdata(&wdev->dev);
+
+ if (test_bit(YB_SUSPENDED, &data->flags))
+ return;
+
+ if (test_bit(YB_DIGITIZER_MODE, &data->flags))
+ clear_bit(YB_DIGITIZER_MODE, &data->flags);
+ else
+ set_bit(YB_DIGITIZER_MODE, &data->flags);
+
+ /*
+ * We are called from the ACPI core and the driver [un]binding which is
+ * done also needs ACPI functions, use a workqueue to avoid deadlocking.
+ */
+ schedule_work(&data->work);
+}
+
+static enum led_brightness kbd_brightness_get(struct led_classdev *cdev)
+{
+ struct yogabook_wmi *data =
+ container_of(cdev, struct yogabook_wmi, kbd_bl_led);
+
+ return data->brightness;
+}
+
+static int kbd_brightness_set(struct led_classdev *cdev,
+ enum led_brightness value)
+{
+ struct yogabook_wmi *data =
+ container_of(cdev, struct yogabook_wmi, kbd_bl_led);
+ struct wmi_device *wdev = data->wdev;
+
+ if ((value < 0) || (value > 255))
+ return -EINVAL;
+
+ data->brightness = value;
+
+ if (data->kbd_adev->power.state != ACPI_STATE_D0)
+ return 0;
+
+ return yogabook_wmi_set_kbd_backlight(wdev, data->brightness);
+}
+
+static int yogabook_wmi_probe(struct wmi_device *wdev, const void *context)
+{
+ struct yogabook_wmi *data;
+ int r;
+
+ data = devm_kzalloc(&wdev->dev, sizeof(struct yogabook_wmi), GFP_KERNEL);
+ if (data == NULL)
+ return -ENOMEM;
+
+ dev_set_drvdata(&wdev->dev, data);
+
+ data->wdev = wdev;
+ data->brightness = YB_KBD_BL_DEFAULT;
+ set_bit(YB_KBD_IS_ON, &data->flags);
+ set_bit(YB_DIGITIZER_IS_ON, &data->flags);
+
+ r = devm_work_autocancel(&wdev->dev, &data->work, yogabook_wmi_work);
+ if (r)
+ return r;
+
+ data->kbd_adev = acpi_dev_get_first_match_dev("GDIX1001", NULL, -1);
+ if (!data->kbd_adev) {
+ dev_err(&wdev->dev, "Cannot find the touchpad device in ACPI tables\n");
+ return -ENODEV;
+ }
+
+ data->dig_adev = acpi_dev_get_first_match_dev("WCOM0019", NULL, -1);
+ if (!data->dig_adev) {
+ dev_err(&wdev->dev, "Cannot find the digitizer device in ACPI tables\n");
+ r = -ENODEV;
+ goto error_put_devs;
+ }
+
+ data->kbd_dev = get_device(acpi_get_first_physical_node(data->kbd_adev));
+ if (!data->kbd_dev || !data->kbd_dev->driver) {
+ r = -EPROBE_DEFER;
+ goto error_put_devs;
+ }
+
+ data->dig_dev = get_device(acpi_get_first_physical_node(data->dig_adev));
+ if (!data->dig_dev || !data->dig_dev->driver) {
+ r = -EPROBE_DEFER;
+ goto error_put_devs;
+ }
+
+ schedule_work(&data->work);
+
+ data->kbd_bl_led.name = "ybwmi::kbd_backlight";
+ data->kbd_bl_led.brightness_set_blocking = kbd_brightness_set;
+ data->kbd_bl_led.brightness_get = kbd_brightness_get;
+ data->kbd_bl_led.max_brightness = 255;
+
+ r = devm_led_classdev_register(&wdev->dev, &data->kbd_bl_led);
+ if (r < 0) {
+ dev_err_probe(&wdev->dev, r, "Registering backlight LED device\n");
+ goto error_put_devs;
+ }
+
+ return 0;
+
+error_put_devs:
+ put_device(data->dig_dev);
+ put_device(data->kbd_dev);
+ acpi_dev_put(data->dig_adev);
+ acpi_dev_put(data->kbd_adev);
+ return r;
+}
+
+static void yogabook_wmi_remove(struct wmi_device *wdev)
+{
+ struct yogabook_wmi *data = dev_get_drvdata(&wdev->dev);
+
+ put_device(data->dig_dev);
+ put_device(data->kbd_dev);
+ acpi_dev_put(data->dig_adev);
+ acpi_dev_put(data->kbd_adev);
+}
+
+static int __maybe_unused yogabook_wmi_suspend(struct device *dev)
+{
+ struct wmi_device *wdev = container_of(dev, struct wmi_device, dev);
+ struct yogabook_wmi *data = dev_get_drvdata(dev);
+
+ set_bit(YB_SUSPENDED, &data->flags);
+
+ flush_work(&data->work);
+
+ /* Turn off the pen button at sleep */
+ if (test_bit(YB_DIGITIZER_IS_ON, &data->flags))
+ yogabook_wmi_do_action(wdev, YB_PAD_DISABLE);
+
+ return 0;
+}
+
+static int __maybe_unused yogabook_wmi_resume(struct device *dev)
+{
+ struct wmi_device *wdev = container_of(dev, struct wmi_device, dev);
+ struct yogabook_wmi *data = dev_get_drvdata(dev);
+
+ if (test_bit(YB_KBD_IS_ON, &data->flags)) {
+ /* Ensure keyboard touchpad is on before we call KBLC() */
+ acpi_device_set_power(data->kbd_adev, ACPI_STATE_D0);
+ yogabook_wmi_set_kbd_backlight(wdev, data->brightness);
+ }
+
+ if (test_bit(YB_DIGITIZER_IS_ON, &data->flags))
+ yogabook_wmi_do_action(wdev, YB_PAD_ENABLE);
+
+ clear_bit(YB_SUSPENDED, &data->flags);
+
+ return 0;
+}
+
+static const struct wmi_device_id yogabook_wmi_id_table[] = {
+ {
+ .guid_string = YB_MBTN_EVENT_GUID,
+ },
+ { } /* Terminating entry */
+};
+
+static SIMPLE_DEV_PM_OPS(yogabook_wmi_pm_ops,
+ yogabook_wmi_suspend, yogabook_wmi_resume);
+
+static struct wmi_driver yogabook_wmi_driver = {
+ .driver = {
+ .name = "yogabook-wmi",
+ .pm = &yogabook_wmi_pm_ops,
+ },
+ .no_notify_data = true,
+ .id_table = yogabook_wmi_id_table,
+ .probe = yogabook_wmi_probe,
+ .remove = yogabook_wmi_remove,
+ .notify = yogabook_wmi_notify,
+};
+module_wmi_driver(yogabook_wmi_driver);
+
+MODULE_DEVICE_TABLE(wmi, yogabook_wmi_id_table);
+MODULE_AUTHOR("Yauhen Kharuzhy");
+MODULE_DESCRIPTION("Lenovo Yoga Book WMI driver");
+MODULE_LICENSE("GPL v2");
projects / platform / kernel / linux-starfive.git / commitdiff