Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/platform/x86/huawei-wmi.c b/drivers/platform/x86/huawei-wmi.c
new file mode 100644
index 0000000..195a7f3
--- /dev/null
+++ b/drivers/platform/x86/huawei-wmi.c
@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Huawei WMI hotkeys
+ *
+ *  Copyright (C) 2018	      Ayman Bagabas <ayman.bagabas@gmail.com>
+ */
+
+#include <linux/acpi.h>
+#include <linux/input.h>
+#include <linux/input/sparse-keymap.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+#include <linux/wmi.h>
+
+/*
+ * Huawei WMI GUIDs
+ */
+#define WMI0_EVENT_GUID "59142400-C6A3-40fa-BADB-8A2652834100"
+#define AMW0_EVENT_GUID "ABBC0F5C-8EA1-11D1-A000-C90629100000"
+
+#define WMI0_EXPENSIVE_GUID "39142400-C6A3-40fa-BADB-8A2652834100"
+
+struct huawei_wmi_priv {
+	struct input_dev *idev;
+	struct led_classdev cdev;
+	acpi_handle handle;
+	char *acpi_method;
+};
+
+static const struct key_entry huawei_wmi_keymap[] = {
+	{ KE_KEY,    0x281, { KEY_BRIGHTNESSDOWN } },
+	{ KE_KEY,    0x282, { KEY_BRIGHTNESSUP } },
+	{ KE_KEY,    0x284, { KEY_MUTE } },
+	{ KE_KEY,    0x285, { KEY_VOLUMEDOWN } },
+	{ KE_KEY,    0x286, { KEY_VOLUMEUP } },
+	{ KE_KEY,    0x287, { KEY_MICMUTE } },
+	{ KE_KEY,    0x289, { KEY_WLAN } },
+	// Huawei |M| key
+	{ KE_KEY,    0x28a, { KEY_CONFIG } },
+	// Keyboard backlight
+	{ KE_IGNORE, 0x293, { KEY_KBDILLUMTOGGLE } },
+	{ KE_IGNORE, 0x294, { KEY_KBDILLUMUP } },
+	{ KE_IGNORE, 0x295, { KEY_KBDILLUMUP } },
+	{ KE_END,	 0 }
+};
+
+static int huawei_wmi_micmute_led_set(struct led_classdev *led_cdev,
+		enum led_brightness brightness)
+{
+	struct huawei_wmi_priv *priv = dev_get_drvdata(led_cdev->dev->parent);
+	acpi_status status;
+	union acpi_object args[3];
+	struct acpi_object_list arg_list = {
+		.pointer = args,
+		.count = ARRAY_SIZE(args),
+	};
+
+	args[0].type = args[1].type = args[2].type = ACPI_TYPE_INTEGER;
+	args[1].integer.value = 0x04;
+
+	if (strcmp(priv->acpi_method, "SPIN") == 0) {
+		args[0].integer.value = 0;
+		args[2].integer.value = brightness ? 1 : 0;
+	} else if (strcmp(priv->acpi_method, "WPIN") == 0) {
+		args[0].integer.value = 1;
+		args[2].integer.value = brightness ? 0 : 1;
+	} else {
+		return -EINVAL;
+	}
+
+	status = acpi_evaluate_object(priv->handle, priv->acpi_method, &arg_list, NULL);
+	if (ACPI_FAILURE(status))
+		return -ENXIO;
+
+	return 0;
+}
+
+static int huawei_wmi_leds_setup(struct wmi_device *wdev)
+{
+	struct huawei_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
+
+	priv->handle = ec_get_handle();
+	if (!priv->handle)
+		return 0;
+
+	if (acpi_has_method(priv->handle, "SPIN"))
+		priv->acpi_method = "SPIN";
+	else if (acpi_has_method(priv->handle, "WPIN"))
+		priv->acpi_method = "WPIN";
+	else
+		return 0;
+
+	priv->cdev.name = "platform::micmute";
+	priv->cdev.max_brightness = 1;
+	priv->cdev.brightness_set_blocking = huawei_wmi_micmute_led_set;
+	priv->cdev.default_trigger = "audio-micmute";
+	priv->cdev.brightness = ledtrig_audio_get(LED_AUDIO_MICMUTE);
+	priv->cdev.dev = &wdev->dev;
+	priv->cdev.flags = LED_CORE_SUSPENDRESUME;
+
+	return devm_led_classdev_register(&wdev->dev, &priv->cdev);
+}
+
+static void huawei_wmi_process_key(struct wmi_device *wdev, int code)
+{
+	struct huawei_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
+	const struct key_entry *key;
+
+	/*
+	 * WMI0 uses code 0x80 to indicate a hotkey event.
+	 * The actual key is fetched from the method WQ00
+	 * using WMI0_EXPENSIVE_GUID.
+	 */
+	if (code == 0x80) {
+		struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
+		union acpi_object *obj;
+		acpi_status status;
+
+		status = wmi_query_block(WMI0_EXPENSIVE_GUID, 0, &response);
+		if (ACPI_FAILURE(status))
+			return;
+
+		obj = (union acpi_object *)response.pointer;
+		if (obj && obj->type == ACPI_TYPE_INTEGER)
+			code = obj->integer.value;
+
+		kfree(response.pointer);
+	}
+
+	key = sparse_keymap_entry_from_scancode(priv->idev, code);
+	if (!key) {
+		dev_info(&wdev->dev, "Unknown key pressed, code: 0x%04x\n", code);
+		return;
+	}
+
+	sparse_keymap_report_entry(priv->idev, key, 1, true);
+}
+
+static void huawei_wmi_notify(struct wmi_device *wdev,
+		union acpi_object *obj)
+{
+	if (obj->type == ACPI_TYPE_INTEGER)
+		huawei_wmi_process_key(wdev, obj->integer.value);
+	else
+		dev_info(&wdev->dev, "Bad response type %d\n", obj->type);
+}
+
+static int huawei_wmi_input_setup(struct wmi_device *wdev)
+{
+	struct huawei_wmi_priv *priv = dev_get_drvdata(&wdev->dev);
+	int err;
+
+	priv->idev = devm_input_allocate_device(&wdev->dev);
+	if (!priv->idev)
+		return -ENOMEM;
+
+	priv->idev->name = "Huawei WMI hotkeys";
+	priv->idev->phys = "wmi/input0";
+	priv->idev->id.bustype = BUS_HOST;
+	priv->idev->dev.parent = &wdev->dev;
+
+	err = sparse_keymap_setup(priv->idev, huawei_wmi_keymap, NULL);
+	if (err)
+		return err;
+
+	return input_register_device(priv->idev);
+}
+
+static int huawei_wmi_probe(struct wmi_device *wdev, const void *context)
+{
+	struct huawei_wmi_priv *priv;
+	int err;
+
+	priv = devm_kzalloc(&wdev->dev, sizeof(struct huawei_wmi_priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	dev_set_drvdata(&wdev->dev, priv);
+
+	err = huawei_wmi_input_setup(wdev);
+	if (err)
+		return err;
+
+	return huawei_wmi_leds_setup(wdev);
+}
+
+static const struct wmi_device_id huawei_wmi_id_table[] = {
+	{ .guid_string = WMI0_EVENT_GUID },
+	{ .guid_string = AMW0_EVENT_GUID },
+	{  }
+};
+
+static struct wmi_driver huawei_wmi_driver = {
+	.driver = {
+		.name = "huawei-wmi",
+	},
+	.id_table = huawei_wmi_id_table,
+	.probe = huawei_wmi_probe,
+	.notify = huawei_wmi_notify,
+};
+
+module_wmi_driver(huawei_wmi_driver);
+
+MODULE_DEVICE_TABLE(wmi, huawei_wmi_id_table);
+MODULE_AUTHOR("Ayman Bagabas <ayman.bagabas@gmail.com>");
+MODULE_DESCRIPTION("Huawei WMI hotkeys");
+MODULE_LICENSE("GPL v2");