linux/drivers/platform/x86/intel-vbtn.c

189 lines
4.7 KiB
C

/*
* 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);