4 files changed, 207 insertions, 0 deletions

diff --git a/MAINTAINERS b/MAINTAINERS
index 16700e4fcc4a..f1efeae1fccd 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5903,6 +5903,12 @@ L:	platform-driver-x86@vger.kernel.org
 S:      Maintained
 F:      drivers/platform/x86/intel-hid.c
 
+INTEL VIRTUAL BUTTON DRIVER
+M:      AceLan Kao <acelan.kao@canonical.com>
+L:      platform-driver-x86@vger.kernel.org
+S:      Maintained
+F:      drivers/platform/x86/intel-vbtn.c
+
 INTEL IDLE DRIVER
 M:      Len Brown <lenb@kernel.org>
 L:      linux-pm@vger.kernel.org
diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index b0b98e413343..bdf027716f3e 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -774,6 +774,18 @@ config INTEL_HID_EVENT
           To compile this driver as a module, choose M here: the module will
           be called intel_hid.
 
+config INTEL_VBTN
+        tristate "INTEL VIRTUAL BUTTON"
+        depends on ACPI
+        depends on INPUT
+        select INPUT_SPARSEKMAP
+        help
+          This driver provides support for the Intel Virtual Button interface.
+          Some laptops require this driver for power button support.
+
+          To compile this driver as a module, choose M here: the module will
+          be called intel_vbtn.
+
 config INTEL_SCU_IPC
         bool "Intel SCU IPC Support"
         depends on X86_INTEL_MID
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 9b11b4073e03..2efa86d2a1a7 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_TOSHIBA_BT_RFKILL)	+= toshiba_bluetooth.o
 obj-$(CONFIG_TOSHIBA_HAPS)      += toshiba_haps.o
 obj-$(CONFIG_TOSHIBA_WMI)       += toshiba-wmi.o
 obj-$(CONFIG_INTEL_HID_EVENT)   += intel-hid.o
+obj-$(CONFIG_INTEL_VBTN)        += intel-vbtn.o
 obj-$(CONFIG_INTEL_SCU_IPC)     += intel_scu_ipc.o
 obj-$(CONFIG_INTEL_SCU_IPC_UTIL) += intel_scu_ipcutil.o
 obj-$(CONFIG_INTEL_MFLD_THERMAL) += intel_mid_thermal.o
diff --git a/drivers/platform/x86/intel-vbtn.c b/drivers/platform/x86/intel-vbtn.c
new file mode 100644
index 000000000000..146d02f8c9bc
--- /dev/null
+++ b/drivers/platform/x86/intel-vbtn.c
@@ -0,0 +1,188 @@
+/*
+ *  Intel Virtual Button driver for Windows 8.1+
+ *
+ *  Copyright (C) 2016 AceLan Kao <acelan.kao@canonical.com>
+ *  Copyright (C) 2016 Alex Hung <alex.hung@canonical.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.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+#include <linux/input/sparse-keymap.h>
+#include <linux/acpi.h>
+#include <acpi/acpi_bus.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("AceLan Kao");
+
+static const struct acpi_device_id intel_vbtn_ids[] = {
+        {"INT33D6", 0},
+        {"", 0},
+};
+
+/* In theory, these are HID usages. */
+static const struct key_entry intel_vbtn_keymap[] = {
+        { KE_IGNORE, 0xC0, { KEY_POWER } },     /* power key press */
+        { KE_KEY, 0xC1, { KEY_POWER } },        /* power key release */
+        { KE_END },
+};
+
+struct intel_vbtn_priv {
+        struct input_dev *input_dev;
+};
+
+static int intel_vbtn_input_setup(struct platform_device *device)
+{
+        struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
+        int ret;
+
+        priv->input_dev = input_allocate_device();
+        if (!priv->input_dev)
+                return -ENOMEM;
+
+        ret = sparse_keymap_setup(priv->input_dev, intel_vbtn_keymap, NULL);
+        if (ret)
+                goto err_free_device;
+
+        priv->input_dev->dev.parent = &device->dev;
+        priv->input_dev->name = "Intel Virtual Button driver";
+        priv->input_dev->id.bustype = BUS_HOST;
+
+        ret = input_register_device(priv->input_dev);
+        if (ret)
+                goto err_free_device;
+
+        return 0;
+
+err_free_device:
+        input_free_device(priv->input_dev);
+        return ret;
+}
+
+static void intel_vbtn_input_destroy(struct platform_device *device)
+{
+        struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
+
+        input_unregister_device(priv->input_dev);
+}
+
+static void notify_handler(acpi_handle handle, u32 event, void *context)
+{
+        struct platform_device *device = context;
+        struct intel_vbtn_priv *priv = dev_get_drvdata(&device->dev);
+
+        if (!sparse_keymap_report_event(priv->input_dev, event, 1, true))
+                dev_info(&device->dev, "unknown event index 0x%x\n",
+                         event);
+}
+
+static int intel_vbtn_probe(struct platform_device *device)
+{
+        acpi_handle handle = ACPI_HANDLE(&device->dev);
+        struct intel_vbtn_priv *priv;
+        acpi_status status;
+        int err;
+
+        status = acpi_evaluate_object(handle, "VBDL", NULL, NULL);
+        if (!ACPI_SUCCESS(status)) {
+                dev_warn(&device->dev, "failed to read Intel Virtual Button driver\n");
+                return -ENODEV;
+        }
+
+        priv = devm_kzalloc(&device->dev, sizeof(*priv), GFP_KERNEL);
+        if (!priv)
+                return -ENOMEM;
+        dev_set_drvdata(&device->dev, priv);
+
+        err = intel_vbtn_input_setup(device);
+        if (err) {
+                pr_err("Failed to setup Intel Virtual Button\n");
+                return err;
+        }
+
+        status = acpi_install_notify_handler(handle,
+                                             ACPI_DEVICE_NOTIFY,
+                                             notify_handler,
+                                             device);
+        if (ACPI_FAILURE(status)) {
+                err = -EBUSY;
+                goto err_remove_input;
+        }
+
+        return 0;
+
+err_remove_input:
+        intel_vbtn_input_destroy(device);
+
+        return err;
+}
+
+static int intel_vbtn_remove(struct platform_device *device)
+{
+        acpi_handle handle = ACPI_HANDLE(&device->dev);
+
+        intel_vbtn_input_destroy(device);
+        acpi_remove_notify_handler(handle, ACPI_DEVICE_NOTIFY, notify_handler);
+
+        /*
+         * Even if we failed to shut off the event stream, we can still
+         * safely detach from the device.
+         */
+        return 0;
+}
+
+static struct platform_driver intel_vbtn_pl_driver = {
+        .driver = {
+                .name = "intel-vbtn",
+                .acpi_match_table = intel_vbtn_ids,
+        },
+        .probe = intel_vbtn_probe,
+        .remove = intel_vbtn_remove,
+};
+MODULE_DEVICE_TABLE(acpi, intel_vbtn_ids);
+
+static acpi_status __init
+check_acpi_dev(acpi_handle handle, u32 lvl, void *context, void **rv)
+{
+        const struct acpi_device_id *ids = context;
+        struct acpi_device *dev;
+
+        if (acpi_bus_get_device(handle, &dev) != 0)
+                return AE_OK;
+
+        if (acpi_match_device_ids(dev, ids) == 0)
+                if (acpi_create_platform_device(dev))
+                        dev_info(&dev->dev,
+                                 "intel-vbtn: created platform device\n");
+
+        return AE_OK;
+}
+
+static int __init intel_vbtn_init(void)
+{
+        acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+                            ACPI_UINT32_MAX, check_acpi_dev, NULL,
+                            (void *)intel_vbtn_ids, NULL);
+
+        return platform_driver_register(&intel_vbtn_pl_driver);
+}
+module_init(intel_vbtn_init);
+
+static void __exit intel_vbtn_exit(void)
+{
+        platform_driver_unregister(&intel_vbtn_pl_driver);
+}
+module_exit(intel_vbtn_exit);