1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  Airplane mode button for HP & Xiaomi laptops
  4 *
  5 *  Copyright (C) 2014-2017 Alex Hung <alex.hung@canonical.com>
  6 */
  7
  8#include <linux/kernel.h>
  9#include <linux/module.h>
 10#include <linux/init.h>
 11#include <linux/input.h>
 12#include <linux/platform_device.h>
 13#include <linux/acpi.h>
 14#include <acpi/acpi_bus.h>
 15
 16MODULE_LICENSE("GPL");
 17MODULE_AUTHOR("Alex Hung");
 18MODULE_ALIAS("acpi*:HPQ6001:*");
 19MODULE_ALIAS("acpi*:WSTADEF:*");
 20
 21static struct input_dev *hpwl_input_dev;
 22
 23static const struct acpi_device_id hpwl_ids[] = {
 24	{"HPQ6001", 0},
 25	{"WSTADEF", 0},
 26	{"", 0},
 27};
 28
 29static int hp_wireless_input_setup(void)
 30{
 31	int err;
 32
 33	hpwl_input_dev = input_allocate_device();
 34	if (!hpwl_input_dev)
 35		return -ENOMEM;
 36
 37	hpwl_input_dev->name = "HP Wireless hotkeys";
 38	hpwl_input_dev->phys = "hpq6001/input0";
 39	hpwl_input_dev->id.bustype = BUS_HOST;
 40	hpwl_input_dev->evbit[0] = BIT(EV_KEY);
 41	set_bit(KEY_RFKILL, hpwl_input_dev->keybit);
 42
 43	err = input_register_device(hpwl_input_dev);
 44	if (err)
 45		goto err_free_dev;
 46
 47	return 0;
 48
 49err_free_dev:
 50	input_free_device(hpwl_input_dev);
 51	return err;
 52}
 53
 54static void hp_wireless_input_destroy(void)
 55{
 56	input_unregister_device(hpwl_input_dev);
 57}
 58
 59static void hpwl_notify(struct acpi_device *acpi_dev, u32 event)
 60{
 61	if (event != 0x80) {
 62		pr_info("Received unknown event (0x%x)\n", event);
 63		return;
 64	}
 65
 66	input_report_key(hpwl_input_dev, KEY_RFKILL, 1);
 67	input_sync(hpwl_input_dev);
 68	input_report_key(hpwl_input_dev, KEY_RFKILL, 0);
 69	input_sync(hpwl_input_dev);
 70}
 71
 72static int hpwl_add(struct acpi_device *device)
 73{
 74	int err;
 75
 76	err = hp_wireless_input_setup();
 77	if (err)
 78		pr_err("Failed to setup hp wireless hotkeys\n");
 79
 80	return err;
 81}
 82
 83static int hpwl_remove(struct acpi_device *device)
 84{
 85	hp_wireless_input_destroy();
 86	return 0;
 87}
 88
 89static struct acpi_driver hpwl_driver = {
 90	.name	= "hp-wireless",
 91	.owner	= THIS_MODULE,
 92	.ids	= hpwl_ids,
 93	.ops	= {
 94		.add	= hpwl_add,
 95		.remove	= hpwl_remove,
 96		.notify	= hpwl_notify,
 97	},
 98};
 99
100module_acpi_driver(hpwl_driver);