1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * HID driver for Holtek keyboard |
4 | * Copyright (c) 2012 Tom Harwood |
5 | */ |
6 | |
7 | /* |
8 | */ |
9 | |
10 | #include <linux/device.h> |
11 | #include <linux/hid.h> |
12 | #include <linux/module.h> |
13 | #include <linux/usb.h> |
14 | |
15 | #include "hid-ids.h" |
16 | #include "usbhid/usbhid.h" |
17 | |
18 | /* Holtek based keyboards (USB ID 04d9:a055) have the following issues: |
19 | * - The report descriptor specifies an excessively large number of consumer |
20 | * usages (2^15), which is more than HID_MAX_USAGES. This prevents proper |
21 | * parsing of the report descriptor. |
22 | * - The report descriptor reports on caps/scroll/num lock key presses, but |
23 | * doesn't have an LED output usage block. |
24 | * |
25 | * The replacement descriptor below fixes the number of consumer usages, |
26 | * and provides an LED output usage block. LED output events are redirected |
27 | * to the boot interface. |
28 | */ |
29 | |
30 | static __u8 holtek_kbd_rdesc_fixed[] = { |
31 | /* Original report descriptor, with reduced number of consumer usages */ |
32 | 0x05, 0x01, /* Usage Page (Desktop), */ |
33 | 0x09, 0x80, /* Usage (Sys Control), */ |
34 | 0xA1, 0x01, /* Collection (Application), */ |
35 | 0x85, 0x01, /* Report ID (1), */ |
36 | 0x19, 0x81, /* Usage Minimum (Sys Power Down), */ |
37 | 0x29, 0x83, /* Usage Maximum (Sys Wake Up), */ |
38 | 0x15, 0x00, /* Logical Minimum (0), */ |
39 | 0x25, 0x01, /* Logical Maximum (1), */ |
40 | 0x95, 0x03, /* Report Count (3), */ |
41 | 0x75, 0x01, /* Report Size (1), */ |
42 | 0x81, 0x02, /* Input (Variable), */ |
43 | 0x95, 0x01, /* Report Count (1), */ |
44 | 0x75, 0x05, /* Report Size (5), */ |
45 | 0x81, 0x01, /* Input (Constant), */ |
46 | 0xC0, /* End Collection, */ |
47 | 0x05, 0x0C, /* Usage Page (Consumer), */ |
48 | 0x09, 0x01, /* Usage (Consumer Control), */ |
49 | 0xA1, 0x01, /* Collection (Application), */ |
50 | 0x85, 0x02, /* Report ID (2), */ |
51 | 0x19, 0x00, /* Usage Minimum (00h), */ |
52 | 0x2A, 0xFF, 0x2F, /* Usage Maximum (0x2FFF), previously 0x7FFF */ |
53 | 0x15, 0x00, /* Logical Minimum (0), */ |
54 | 0x26, 0xFF, 0x2F, /* Logical Maximum (0x2FFF),previously 0x7FFF*/ |
55 | 0x95, 0x01, /* Report Count (1), */ |
56 | 0x75, 0x10, /* Report Size (16), */ |
57 | 0x81, 0x00, /* Input, */ |
58 | 0xC0, /* End Collection, */ |
59 | 0x05, 0x01, /* Usage Page (Desktop), */ |
60 | 0x09, 0x06, /* Usage (Keyboard), */ |
61 | 0xA1, 0x01, /* Collection (Application), */ |
62 | 0x85, 0x03, /* Report ID (3), */ |
63 | 0x95, 0x38, /* Report Count (56), */ |
64 | 0x75, 0x01, /* Report Size (1), */ |
65 | 0x15, 0x00, /* Logical Minimum (0), */ |
66 | 0x25, 0x01, /* Logical Maximum (1), */ |
67 | 0x05, 0x07, /* Usage Page (Keyboard), */ |
68 | 0x19, 0xE0, /* Usage Minimum (KB Leftcontrol), */ |
69 | 0x29, 0xE7, /* Usage Maximum (KB Right GUI), */ |
70 | 0x19, 0x00, /* Usage Minimum (None), */ |
71 | 0x29, 0x2F, /* Usage Maximum (KB Lboxbracket And Lbrace),*/ |
72 | 0x81, 0x02, /* Input (Variable), */ |
73 | 0xC0, /* End Collection, */ |
74 | 0x05, 0x01, /* Usage Page (Desktop), */ |
75 | 0x09, 0x06, /* Usage (Keyboard), */ |
76 | 0xA1, 0x01, /* Collection (Application), */ |
77 | 0x85, 0x04, /* Report ID (4), */ |
78 | 0x95, 0x38, /* Report Count (56), */ |
79 | 0x75, 0x01, /* Report Size (1), */ |
80 | 0x15, 0x00, /* Logical Minimum (0), */ |
81 | 0x25, 0x01, /* Logical Maximum (1), */ |
82 | 0x05, 0x07, /* Usage Page (Keyboard), */ |
83 | 0x19, 0x30, /* Usage Minimum (KB Rboxbracket And Rbrace),*/ |
84 | 0x29, 0x67, /* Usage Maximum (KP Equals), */ |
85 | 0x81, 0x02, /* Input (Variable), */ |
86 | 0xC0, /* End Collection */ |
87 | |
88 | /* LED usage for the boot protocol interface */ |
89 | 0x05, 0x01, /* Usage Page (Desktop), */ |
90 | 0x09, 0x06, /* Usage (Keyboard), */ |
91 | 0xA1, 0x01, /* Collection (Application), */ |
92 | 0x05, 0x08, /* Usage Page (LED), */ |
93 | 0x19, 0x01, /* Usage Minimum (01h), */ |
94 | 0x29, 0x03, /* Usage Maximum (03h), */ |
95 | 0x15, 0x00, /* Logical Minimum (0), */ |
96 | 0x25, 0x01, /* Logical Maximum (1), */ |
97 | 0x75, 0x01, /* Report Size (1), */ |
98 | 0x95, 0x03, /* Report Count (3), */ |
99 | 0x91, 0x02, /* Output (Variable), */ |
100 | 0x95, 0x05, /* Report Count (5), */ |
101 | 0x91, 0x01, /* Output (Constant), */ |
102 | 0xC0, /* End Collection */ |
103 | }; |
104 | |
105 | static __u8 *holtek_kbd_report_fixup(struct hid_device *hdev, __u8 *rdesc, |
106 | unsigned int *rsize) |
107 | { |
108 | struct usb_interface *intf = to_usb_interface(hdev->dev.parent); |
109 | |
110 | if (intf->cur_altsetting->desc.bInterfaceNumber == 1) { |
111 | rdesc = holtek_kbd_rdesc_fixed; |
112 | *rsize = sizeof(holtek_kbd_rdesc_fixed); |
113 | } |
114 | return rdesc; |
115 | } |
116 | |
117 | static int holtek_kbd_input_event(struct input_dev *dev, unsigned int type, |
118 | unsigned int code, |
119 | int value) |
120 | { |
121 | struct hid_device *hid = input_get_drvdata(dev); |
122 | struct usb_device *usb_dev = hid_to_usb_dev(hid); |
123 | |
124 | /* Locate the boot interface, to receive the LED change events */ |
125 | struct usb_interface *boot_interface = usb_ifnum_to_if(dev: usb_dev, ifnum: 0); |
126 | struct hid_device *boot_hid; |
127 | struct hid_input *boot_hid_input; |
128 | |
129 | if (unlikely(boot_interface == NULL)) |
130 | return -ENODEV; |
131 | |
132 | boot_hid = usb_get_intfdata(intf: boot_interface); |
133 | if (list_empty(head: &boot_hid->inputs)) { |
134 | hid_err(hid, "no inputs found\n" ); |
135 | return -ENODEV; |
136 | } |
137 | boot_hid_input = list_first_entry(&boot_hid->inputs, |
138 | struct hid_input, list); |
139 | |
140 | return boot_hid_input->input->event(boot_hid_input->input, type, code, |
141 | value); |
142 | } |
143 | |
144 | static int holtek_kbd_probe(struct hid_device *hdev, |
145 | const struct hid_device_id *id) |
146 | { |
147 | struct usb_interface *intf; |
148 | int ret; |
149 | |
150 | if (!hid_is_usb(hdev)) |
151 | return -EINVAL; |
152 | |
153 | ret = hid_parse(hdev); |
154 | if (!ret) |
155 | ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT); |
156 | |
157 | intf = to_usb_interface(hdev->dev.parent); |
158 | if (!ret && intf->cur_altsetting->desc.bInterfaceNumber == 1) { |
159 | struct hid_input *hidinput; |
160 | list_for_each_entry(hidinput, &hdev->inputs, list) { |
161 | hidinput->input->event = holtek_kbd_input_event; |
162 | } |
163 | } |
164 | |
165 | return ret; |
166 | } |
167 | |
168 | static const struct hid_device_id holtek_kbd_devices[] = { |
169 | { HID_USB_DEVICE(USB_VENDOR_ID_HOLTEK_ALT, |
170 | USB_DEVICE_ID_HOLTEK_ALT_KEYBOARD) }, |
171 | { } |
172 | }; |
173 | MODULE_DEVICE_TABLE(hid, holtek_kbd_devices); |
174 | |
175 | static struct hid_driver holtek_kbd_driver = { |
176 | .name = "holtek_kbd" , |
177 | .id_table = holtek_kbd_devices, |
178 | .report_fixup = holtek_kbd_report_fixup, |
179 | .probe = holtek_kbd_probe |
180 | }; |
181 | module_hid_driver(holtek_kbd_driver); |
182 | |
183 | MODULE_LICENSE("GPL" ); |
184 | |