[PATCH v3 1/3] x86: add support for Huawei WMI hotkeys.

Ayman Bagabas
2018-11-08T17:17:32Z

This driver adds support for missing hotkeys on some Huawei laptops.
Currently, only Huawei Matebook X and Matebook X Pro is supported.

Signed-off-by: Ayman Bagabas <ayman.bagabas@gmail.com>
---
drivers/platform/x86/Kconfig | 11 ++
drivers/platform/x86/Makefile | 1 +
drivers/platform/x86/huawei_wmi.c | 235 ++++++++++++++++++++++++++++++
3 files changed, 247 insertions(+)
create mode 100644 drivers/platform/x86/huawei_wmi.c

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index 54f6a40c75c6..b45c1294df7e 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -1288,6 +1288,17 @@ config INTEL_ATOMISP2_PM
To compile this driver as a module, choose M here: the module
will be called intel_atomisp2_pm.

+config HUAWEI_LAPTOP
+ tristate "Huawei WMI hotkeys driver"
+ depends on ACPI
+ depends on ACPI_WMI
+ depends on INPUT
+ select INPUT_SPARSEKMAP
+ help
+ This driver provides support for Huawei WMI hotkeys.
+ It enables the missing keys and adds support to the micmute
+ LED found on some of these laptops.
+
endif # X86_PLATFORM_DEVICES

config PMC_ATOM
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 39ae94135406..ee93655d8bc1 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -32,6 +32,7 @@ obj-$(CONFIG_ACERHDF) += acerhdf.o
obj-$(CONFIG_HP_ACCEL) += hp_accel.o
obj-$(CONFIG_HP_WIRELESS) += hp-wireless.o
obj-$(CONFIG_HP_WMI) += hp-wmi.o
+obj-$(CONFIG_HUAWEI_LAPTOP) += huawei_wmi.o
obj-$(CONFIG_AMILO_RFKILL) += amilo-rfkill.o
obj-$(CONFIG_GPD_POCKET_FAN) += gpd-pocket-fan.o
obj-$(CONFIG_TC1100_WMI) += tc1100-wmi.o
diff --git a/drivers/platform/x86/huawei_wmi.c b/drivers/platform/x86/huawei_wmi.c
new file mode 100644
index 000000000000..658c44ab2126
--- /dev/null
+++ b/drivers/platform/x86/huawei_wmi.c
@@ -0,0 +1,235 @@
+/*
+ * Huawei WMI hotkeys
+ *
+ * Copyright (C) 2018 Ayman Bagabas <ayman.bagabas@gmail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#include <linux/acpi.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/input/sparse-keymap.h>
+#include <linux/module.h>
+
+MODULE_AUTHOR("Ayman Bagabas <ayman.bagabas@gmail.com>");
+MODULE_DESCRIPTION("Huawei WMI hotkeys");
+MODULE_LICENSE("GPL");
+
+/*
+ * Huawei WMI Events GUIDs
+ */
+#define MBX_EVENT_GUID "59142400-C6A3-40fa-BADB-8A2652834100"
+#define MBXP_EVENT_GUID "ABBC0F5C-8EA1-11D1-A000-C90629100000"
+
+MODULE_ALIAS("wmi:"MBX_EVENT_GUID);
+MODULE_ALIAS("wmi:"MBXP_EVENT_GUID);
+
+static const struct key_entry huawei_wmi_keymap[] __initconst = {
+ { 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| button
+ { KE_KEY, 0x28a, { KEY_PROG1 } },
+ // Keyboard light
+ { KE_IGNORE, 0x293, { KEY_KBDILLUMTOGGLE } },
+ { KE_IGNORE, 0x294, { KEY_KBDILLUMUP } },
+ { KE_IGNORE, 0x295, { KEY_KBDILLUMUP } },
+ { KE_END, 0 }
+};
+
+static char *event_guid;
+static struct input_dev *inputdev;
+
+int huawei_wmi_micmute_led_set(bool on)
+{
+ acpi_handle handle = ACPI_HANDLE(&inputdev->dev);
+ char *method;
+ union acpi_object args[3];
+ args[0].type = args[1].type = args[2].type = ACPI_TYPE_INTEGER;
+ args[1].integer.value = 0x04;
+ struct acpi_object_list arg_list = {
+ .pointer = args,
+ .count = ARRAY_SIZE(args),
+ };
+
+ if (acpi_has_method(handle, method = "\\_SB.PCI0.LPCB.EC0.SPIN")) {
+ args[0].integer.value = 0;
+ args[2].integer.value = on ? 1 : 0;
+ } else if (acpi_has_method(handle, method = "\\_SB.PCI0.LPCB.EC0.WPIN")) {
+ args[0].integer.value = 1;
+ args[2].integer.value = on ? 0 : 1;
+ } else {
+ pr_err("Unable to find ACPI method\n");
+ return -1;
+ }
+
+ acpi_evaluate_object(handle, method, &arg_list, NULL);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(huawei_wmi_micmute_led_set);
+
+static void huawei_wmi_process_key(struct input_dev *inputdev, int code)
+{
+ const struct key_entry *key;
+
+ /*
+ * MBX uses code 0x80 to indicate a hotkey event.
+ * The actual key is fetched from the method WQ00
+ */
+ if (code == 0x80) {
+ acpi_status status;
+ unsigned long long result;
+ const char *method = "\\WMI0.WQ00";
+ union acpi_object args[] = {
+ { .type = ACPI_TYPE_INTEGER },
+ };
+ args[0].integer.value = 0;
+ struct acpi_object_list arg_list = {
+ .pointer = args,
+ .count = ARRAY_SIZE(args),
+ };
+
+ status = acpi_evaluate_integer(ACPI_HANDLE(&inputdev->dev), (char *)method, &arg_list, &result);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&inputdev->dev, "Unable to evaluate ACPI method %s\n", method);
+ return;
+ }
+
+ code = result;
+ }
+
+ key = sparse_keymap_entry_from_scancode(inputdev, code);
+ if (!key) {
+ dev_info(&inputdev->dev, "Unknown key pressed, code: 0x%04x\n", code);
+ return;
+ }
+
+ /*
+ * The MBXP handles backlight natively using ACPI,
+ * but not the MBX. If MBXP is being used, skip reporting event.
+ */
+ if ((key->sw.code == KEY_BRIGHTNESSUP
+ || key->sw.code == KEY_BRIGHTNESSDOWN)
+ && strcmp(event_guid, MBXP_EVENT_GUID) == 0)
+ return;
+
+ sparse_keymap_report_entry(inputdev, key, 1, true);
+}
+
+static void huawei_wmi_notify(u32 value, void *context)
+{
+ struct acpi_buffer response = { ACPI_ALLOCATE_BUFFER, NULL };
+ union acpi_object *obj;
+ acpi_status status;
+ struct input_dev *inputdev = (struct input_dev*)context;
+
+ status = wmi_get_event_data(value, &response);
+ if (ACPI_FAILURE(status)) {
+ dev_err(&inputdev->dev, "Bad event status 0x%x\n", status);
+ return;
+ }
+
+ obj = (union acpi_object *)response.pointer;
+ if (!obj)
+ return;
+
+ if (obj->type == ACPI_TYPE_INTEGER)
+ huawei_wmi_process_key(inputdev, obj->integer.value);
+ else
+ dev_info(&inputdev->dev, "Unknown response received %d\n", obj->type);
+
+ kfree(response.pointer);
+}
+
+static int huawei_wmi_input_init(void)
+{
+ acpi_status status;
+ int err;
+
+ inputdev = input_allocate_device();
+ if (!inputdev)
+ return -ENOMEM;
+
+ inputdev->name = "Huawei WMI hotkeys";
+ inputdev->phys = "wmi/input0";
+ inputdev->id.bustype = BUS_HOST;
+
+ err = sparse_keymap_setup(inputdev,
+ huawei_wmi_keymap, NULL);
+ if (err)
+ goto err_free_dev;
+
+ status = wmi_install_notify_handler(event_guid,
+ huawei_wmi_notify,
+ inputdev);
+ if (ACPI_FAILURE(status)) {
+ err = -EIO;
+ goto err_free_dev;
+ }
+
+ err = input_register_device(inputdev);
+ if (err)
+ goto err_remove_notifier;
+
+ return 0;
+
+err_remove_notifier:
+ wmi_remove_notify_handler(event_guid);
+err_free_dev:
+ input_free_device(inputdev);
+ return err;
+}
+
+static void huawei_wmi_input_exit(void)
+{
+ wmi_remove_notify_handler(event_guid);
+ input_unregister_device(inputdev);
+}
+
+static int __init huawei_wmi_init(void)
+{
+ int err;
+
+ if (wmi_has_guid(MBX_EVENT_GUID)) {
+ event_guid = MBX_EVENT_GUID;
+ } else if (wmi_has_guid(MBXP_EVENT_GUID)) {
+ event_guid = MBXP_EVENT_GUID;
+ } else {
+ pr_warn("No known WMI GUID found\n");
+ return -ENODEV;
+ }
+
+ err = huawei_wmi_input_init();
+ if (err) {
+ pr_err("Failed to setup input device\n");
+ return err;
+ }
+
+ return 0;
+}
+
+static void __exit huawei_wmi_exit(void)
+{
+ huawei_wmi_input_exit();
+}
+
+module_init(huawei_wmi_init);
+module_exit(huawei_wmi_exit);
--
2.17.2