hp-wireless: new driver for hp wireless button for Windows 8

Signed-off-by: Alex Hung <alex.hung@canonical.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

3 files changed, 144 insertions, 0 deletions

diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig
index a698b928327d..5ae65c11d544 100644
--- a/drivers/platform/x86/Kconfig
+++ b/drivers/platform/x86/Kconfig
@@ -197,6 +197,17 @@ config HP_ACCEL
           To compile this driver as a module, choose M here: the module will
           be called hp_accel.
 
+config HP_WIRELESS
+        tristate "HP WIRELESS"
+        depends on ACPI
+        depends on INPUT
+        help
+         This driver provides supports for new HP wireless button for Windows 8.
+         On such systems the driver should load automatically (via ACPI alias).
+
+         To compile this driver as a module, choose M here: the module will
+         be called hp-wireless.
+
 config HP_WMI
         tristate "HP WMI extras"
         depends on ACPI_WMI
diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefile
index 79bd3c49be3d..9b87cfc42b84 100644
--- a/drivers/platform/x86/Makefile
+++ b/drivers/platform/x86/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_DELL_WMI_AIO)	+= dell-wmi-aio.o
 obj-$(CONFIG_ACER_WMI)          += acer-wmi.o
 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-$(CONFIG_AMILO_RFKILL)      += amilo-rfkill.o
 obj-$(CONFIG_TC1100_WMI)        += tc1100-wmi.o
diff --git a/drivers/platform/x86/hp-wireless.c b/drivers/platform/x86/hp-wireless.c
new file mode 100644
index 000000000000..415348fc1210
--- /dev/null
+++ b/drivers/platform/x86/hp-wireless.c
@@ -0,0 +1,132 @@
+/*
+ *  hp-wireless button for Windows 8
+ *
+ *  Copyright (C) 2014 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.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+#include <linux/acpi.h>
+#include <acpi/acpi_bus.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Alex Hung");
+MODULE_ALIAS("acpi*:HPQ6001:*");
+
+static struct input_dev *hpwl_input_dev;
+
+static const struct acpi_device_id hpwl_ids[] = {
+        {"HPQ6001", 0},
+        {"", 0},
+};
+
+static int hp_wireless_input_setup(void)
+{
+        int err;
+
+        hpwl_input_dev = input_allocate_device();
+        if (!hpwl_input_dev)
+                return -ENOMEM;
+
+        hpwl_input_dev->name = "HP Wireless hotkeys";
+        hpwl_input_dev->phys = "hpq6001/input0";
+        hpwl_input_dev->id.bustype = BUS_HOST;
+        hpwl_input_dev->evbit[0] = BIT(EV_KEY);
+        set_bit(KEY_RFKILL, hpwl_input_dev->keybit);
+
+        err = input_register_device(hpwl_input_dev);
+        if (err)
+                goto err_free_dev;
+
+        return 0;
+
+err_free_dev:
+        input_free_device(hpwl_input_dev);
+        return err;
+}
+
+static void hp_wireless_input_destroy(void)
+{
+        input_unregister_device(hpwl_input_dev);
+}
+
+static void hpwl_notify(struct acpi_device *acpi_dev, u32 event)
+{
+        if (event != 0x80) {
+                pr_info("Received unknown event (0x%x)\n", event);
+                return;
+        }
+
+        input_report_key(hpwl_input_dev, KEY_RFKILL, 1);
+        input_sync(hpwl_input_dev);
+        input_report_key(hpwl_input_dev, KEY_RFKILL, 0);
+        input_sync(hpwl_input_dev);
+}
+
+static int hpwl_add(struct acpi_device *device)
+{
+        int err;
+
+        err = hp_wireless_input_setup();
+        return err;
+}
+
+static int hpwl_remove(struct acpi_device *device)
+{
+        hp_wireless_input_destroy();
+        return 0;
+}
+
+static struct acpi_driver hpwl_driver = {
+        .name   = "hp-wireless",
+        .owner  = THIS_MODULE,
+        .ids    = hpwl_ids,
+        .ops    = {
+                .add    = hpwl_add,
+                .remove = hpwl_remove,
+                .notify = hpwl_notify,
+        },
+};
+
+static int __init hpwl_init(void)
+{
+        int err;
+
+        pr_info("Initializing HPQ6001 module\n");
+        err = acpi_bus_register_driver(&hpwl_driver);
+        if (err) {
+                pr_err("Unable to register HP wireless control driver.\n");
+                goto error_acpi_register;
+        }
+
+        return 0;
+
+error_acpi_register:
+        return err;
+}
+
+static void __exit hpwl_exit(void)
+{
+        pr_info("Exiting HPQ6001 module\n");
+        acpi_bus_unregister_driver(&hpwl_driver);
+}
+
+module_init(hpwl_init);
+module_exit(hpwl_exit);