1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * adv_swbutton.c - Software Button Interface Driver. |
4 | * |
5 | * (C) Copyright 2020 Advantech Corporation, Inc |
6 | * |
7 | */ |
8 | #include <linux/kernel.h> |
9 | #include <linux/module.h> |
10 | #include <linux/input.h> |
11 | #include <linux/acpi.h> |
12 | #include <linux/platform_device.h> |
13 | |
14 | #define ACPI_BUTTON_HID_SWBTN "AHC0310" |
15 | |
16 | #define ACPI_BUTTON_NOTIFY_SWBTN_RELEASE 0x86 |
17 | #define ACPI_BUTTON_NOTIFY_SWBTN_PRESSED 0x85 |
18 | |
19 | struct adv_swbutton { |
20 | struct input_dev *input; |
21 | char phys[32]; |
22 | }; |
23 | |
24 | /*------------------------------------------------------------------------- |
25 | * Driver Interface |
26 | *-------------------------------------------------------------------------- |
27 | */ |
28 | static void adv_swbutton_notify(acpi_handle handle, u32 event, void *context) |
29 | { |
30 | struct platform_device *device = context; |
31 | struct adv_swbutton *button = dev_get_drvdata(dev: &device->dev); |
32 | |
33 | switch (event) { |
34 | case ACPI_BUTTON_NOTIFY_SWBTN_RELEASE: |
35 | input_report_key(dev: button->input, KEY_PROG1, value: 0); |
36 | input_sync(dev: button->input); |
37 | break; |
38 | case ACPI_BUTTON_NOTIFY_SWBTN_PRESSED: |
39 | input_report_key(dev: button->input, KEY_PROG1, value: 1); |
40 | input_sync(dev: button->input); |
41 | break; |
42 | default: |
43 | dev_dbg(&device->dev, "Unsupported event [0x%x]\n" , event); |
44 | } |
45 | } |
46 | |
47 | static int adv_swbutton_probe(struct platform_device *device) |
48 | { |
49 | struct adv_swbutton *button; |
50 | struct input_dev *input; |
51 | acpi_handle handle = ACPI_HANDLE(&device->dev); |
52 | acpi_status status; |
53 | int error; |
54 | |
55 | button = devm_kzalloc(dev: &device->dev, size: sizeof(*button), GFP_KERNEL); |
56 | if (!button) |
57 | return -ENOMEM; |
58 | |
59 | dev_set_drvdata(dev: &device->dev, data: button); |
60 | |
61 | input = devm_input_allocate_device(&device->dev); |
62 | if (!input) |
63 | return -ENOMEM; |
64 | |
65 | button->input = input; |
66 | snprintf(buf: button->phys, size: sizeof(button->phys), fmt: "%s/button/input0" , ACPI_BUTTON_HID_SWBTN); |
67 | |
68 | input->name = "Advantech Software Button" ; |
69 | input->phys = button->phys; |
70 | input->id.bustype = BUS_HOST; |
71 | input->dev.parent = &device->dev; |
72 | set_bit(EV_REP, addr: input->evbit); |
73 | input_set_capability(dev: input, EV_KEY, KEY_PROG1); |
74 | |
75 | error = input_register_device(input); |
76 | if (error) |
77 | return error; |
78 | |
79 | device_init_wakeup(dev: &device->dev, enable: true); |
80 | |
81 | status = acpi_install_notify_handler(device: handle, |
82 | ACPI_DEVICE_NOTIFY, |
83 | handler: adv_swbutton_notify, |
84 | context: device); |
85 | if (ACPI_FAILURE(status)) { |
86 | dev_err(&device->dev, "Error installing notify handler\n" ); |
87 | return -EIO; |
88 | } |
89 | |
90 | return 0; |
91 | } |
92 | |
93 | static void adv_swbutton_remove(struct platform_device *device) |
94 | { |
95 | acpi_handle handle = ACPI_HANDLE(&device->dev); |
96 | |
97 | acpi_remove_notify_handler(device: handle, ACPI_DEVICE_NOTIFY, |
98 | handler: adv_swbutton_notify); |
99 | } |
100 | |
101 | static const struct acpi_device_id button_device_ids[] = { |
102 | {ACPI_BUTTON_HID_SWBTN, 0}, |
103 | {"" , 0}, |
104 | }; |
105 | MODULE_DEVICE_TABLE(acpi, button_device_ids); |
106 | |
107 | static struct platform_driver adv_swbutton_driver = { |
108 | .driver = { |
109 | .name = "adv_swbutton" , |
110 | .acpi_match_table = button_device_ids, |
111 | }, |
112 | .probe = adv_swbutton_probe, |
113 | .remove_new = adv_swbutton_remove, |
114 | }; |
115 | module_platform_driver(adv_swbutton_driver); |
116 | |
117 | MODULE_AUTHOR("Andrea Ho" ); |
118 | MODULE_DESCRIPTION("Advantech ACPI SW Button Driver" ); |
119 | MODULE_LICENSE("GPL v2" ); |
120 | |