1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Airplane mode button for AMD, HP & Xiaomi laptops 4 * 5 * Copyright (C) 2014-2017 Alex Hung <alex.hung@canonical.com> 6 * Copyright (C) 2021 Advanced Micro Devices 7 */ 8 9 #include <linux/kernel.h> 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/input.h> 13 #include <linux/platform_device.h> 14 #include <linux/acpi.h> 15 #include <acpi/acpi_bus.h> 16 17 MODULE_LICENSE("GPL"); 18 MODULE_AUTHOR("Alex Hung"); 19 MODULE_ALIAS("acpi*:HPQ6001:*"); 20 MODULE_ALIAS("acpi*:WSTADEF:*"); 21 MODULE_ALIAS("acpi*:AMDI0051:*"); 22 23 struct wl_button { 24 struct input_dev *input_dev; 25 char phys[32]; 26 }; 27 28 static const struct acpi_device_id wl_ids[] = { 29 {"HPQ6001", 0}, 30 {"WSTADEF", 0}, 31 {"AMDI0051", 0}, 32 {"", 0}, 33 }; 34 35 static int wireless_input_setup(struct acpi_device *device) 36 { 37 struct wl_button *button = acpi_driver_data(device); 38 int err; 39 40 button->input_dev = input_allocate_device(); 41 if (!button->input_dev) 42 return -ENOMEM; 43 44 snprintf(button->phys, sizeof(button->phys), "%s/input0", acpi_device_hid(device)); 45 46 button->input_dev->name = "Wireless hotkeys"; 47 button->input_dev->phys = button->phys; 48 button->input_dev->id.bustype = BUS_HOST; 49 button->input_dev->evbit[0] = BIT(EV_KEY); 50 set_bit(KEY_RFKILL, button->input_dev->keybit); 51 52 err = input_register_device(button->input_dev); 53 if (err) 54 goto err_free_dev; 55 56 return 0; 57 58 err_free_dev: 59 input_free_device(button->input_dev); 60 return err; 61 } 62 63 static void wireless_input_destroy(struct acpi_device *device) 64 { 65 struct wl_button *button = acpi_driver_data(device); 66 67 input_unregister_device(button->input_dev); 68 kfree(button); 69 } 70 71 static void wl_notify(struct acpi_device *acpi_dev, u32 event) 72 { 73 struct wl_button *button = acpi_driver_data(acpi_dev); 74 75 if (event != 0x80) { 76 pr_info("Received unknown event (0x%x)\n", event); 77 return; 78 } 79 80 input_report_key(button->input_dev, KEY_RFKILL, 1); 81 input_sync(button->input_dev); 82 input_report_key(button->input_dev, KEY_RFKILL, 0); 83 input_sync(button->input_dev); 84 } 85 86 static int wl_add(struct acpi_device *device) 87 { 88 struct wl_button *button; 89 int err; 90 91 button = kzalloc(sizeof(struct wl_button), GFP_KERNEL); 92 if (!button) 93 return -ENOMEM; 94 95 device->driver_data = button; 96 97 err = wireless_input_setup(device); 98 if (err) { 99 pr_err("Failed to setup wireless hotkeys\n"); 100 kfree(button); 101 } 102 103 return err; 104 } 105 106 static void wl_remove(struct acpi_device *device) 107 { 108 wireless_input_destroy(device); 109 } 110 111 static struct acpi_driver wl_driver = { 112 .name = "wireless-hotkey", 113 .ids = wl_ids, 114 .ops = { 115 .add = wl_add, 116 .remove = wl_remove, 117 .notify = wl_notify, 118 }, 119 }; 120 121 module_acpi_driver(wl_driver); 122