1/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2#ifndef __UHID_H_
3#define __UHID_H_
4
5/*
6 * User-space I/O driver support for HID subsystem
7 * Copyright (c) 2012 David Herrmann
8 */
9
10/*
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License as published by the Free
13 * Software Foundation; either version 2 of the License, or (at your option)
14 * any later version.
15 */
16
17/*
18 * Public header for user-space communication. We try to keep every structure
19 * aligned but to be safe we also use __attribute__((__packed__)). Therefore,
20 * the communication should be ABI compatible even between architectures.
21 */
22
23#include <linux/input.h>
24#include <linux/types.h>
25#include <linux/hid.h>
26
27enum uhid_event_type {
28 __UHID_LEGACY_CREATE,
29 UHID_DESTROY,
30 UHID_START,
31 UHID_STOP,
32 UHID_OPEN,
33 UHID_CLOSE,
34 UHID_OUTPUT,
35 __UHID_LEGACY_OUTPUT_EV,
36 __UHID_LEGACY_INPUT,
37 UHID_GET_REPORT,
38 UHID_GET_REPORT_REPLY,
39 UHID_CREATE2,
40 UHID_INPUT2,
41 UHID_SET_REPORT,
42 UHID_SET_REPORT_REPLY,
43};
44
45struct uhid_create2_req {
46 __u8 name[128];
47 __u8 phys[64];
48 __u8 uniq[64];
49 __u16 rd_size;
50 __u16 bus;
51 __u32 vendor;
52 __u32 product;
53 __u32 version;
54 __u32 country;
55 __u8 rd_data[HID_MAX_DESCRIPTOR_SIZE];
56} __attribute__((__packed__));
57
58enum uhid_dev_flag {
59 UHID_DEV_NUMBERED_FEATURE_REPORTS = (1ULL << 0),
60 UHID_DEV_NUMBERED_OUTPUT_REPORTS = (1ULL << 1),
61 UHID_DEV_NUMBERED_INPUT_REPORTS = (1ULL << 2),
62};
63
64struct uhid_start_req {
65 __u64 dev_flags;
66};
67
68#define UHID_DATA_MAX 4096
69
70enum uhid_report_type {
71 UHID_FEATURE_REPORT,
72 UHID_OUTPUT_REPORT,
73 UHID_INPUT_REPORT,
74};
75
76struct uhid_input2_req {
77 __u16 size;
78 __u8 data[UHID_DATA_MAX];
79} __attribute__((__packed__));
80
81struct uhid_output_req {
82 __u8 data[UHID_DATA_MAX];
83 __u16 size;
84 __u8 rtype;
85} __attribute__((__packed__));
86
87struct uhid_get_report_req {
88 __u32 id;
89 __u8 rnum;
90 __u8 rtype;
91} __attribute__((__packed__));
92
93struct uhid_get_report_reply_req {
94 __u32 id;
95 __u16 err;
96 __u16 size;
97 __u8 data[UHID_DATA_MAX];
98} __attribute__((__packed__));
99
100struct uhid_set_report_req {
101 __u32 id;
102 __u8 rnum;
103 __u8 rtype;
104 __u16 size;
105 __u8 data[UHID_DATA_MAX];
106} __attribute__((__packed__));
107
108struct uhid_set_report_reply_req {
109 __u32 id;
110 __u16 err;
111} __attribute__((__packed__));
112
113/*
114 * Compat Layer
115 * All these commands and requests are obsolete. You should avoid using them in
116 * new code. We support them for backwards-compatibility, but you might not get
117 * access to new feature in case you use them.
118 */
119
120enum uhid_legacy_event_type {
121 UHID_CREATE = __UHID_LEGACY_CREATE,
122 UHID_OUTPUT_EV = __UHID_LEGACY_OUTPUT_EV,
123 UHID_INPUT = __UHID_LEGACY_INPUT,
124 UHID_FEATURE = UHID_GET_REPORT,
125 UHID_FEATURE_ANSWER = UHID_GET_REPORT_REPLY,
126};
127
128/* Obsolete! Use UHID_CREATE2. */
129struct uhid_create_req {
130 __u8 name[128];
131 __u8 phys[64];
132 __u8 uniq[64];
133 __u8 __user *rd_data;
134 __u16 rd_size;
135
136 __u16 bus;
137 __u32 vendor;
138 __u32 product;
139 __u32 version;
140 __u32 country;
141} __attribute__((__packed__));
142
143/* Obsolete! Use UHID_INPUT2. */
144struct uhid_input_req {
145 __u8 data[UHID_DATA_MAX];
146 __u16 size;
147} __attribute__((__packed__));
148
149/* Obsolete! Kernel uses UHID_OUTPUT exclusively now. */
150struct uhid_output_ev_req {
151 __u16 type;
152 __u16 code;
153 __s32 value;
154} __attribute__((__packed__));
155
156/* Obsolete! Kernel uses ABI compatible UHID_GET_REPORT. */
157struct uhid_feature_req {
158 __u32 id;
159 __u8 rnum;
160 __u8 rtype;
161} __attribute__((__packed__));
162
163/* Obsolete! Use ABI compatible UHID_GET_REPORT_REPLY. */
164struct uhid_feature_answer_req {
165 __u32 id;
166 __u16 err;
167 __u16 size;
168 __u8 data[UHID_DATA_MAX];
169} __attribute__((__packed__));
170
171/*
172 * UHID Events
173 * All UHID events from and to the kernel are encoded as "struct uhid_event".
174 * The "type" field contains a UHID_* type identifier. All payload depends on
175 * that type and can be accessed via ev->u.XYZ accordingly.
176 * If user-space writes short events, they're extended with 0s by the kernel. If
177 * the kernel writes short events, user-space shall extend them with 0s.
178 */
179
180struct uhid_event {
181 __u32 type;
182
183 union {
184 struct uhid_create_req create;
185 struct uhid_input_req input;
186 struct uhid_output_req output;
187 struct uhid_output_ev_req output_ev;
188 struct uhid_feature_req feature;
189 struct uhid_get_report_req get_report;
190 struct uhid_feature_answer_req feature_answer;
191 struct uhid_get_report_reply_req get_report_reply;
192 struct uhid_create2_req create2;
193 struct uhid_input2_req input2;
194 struct uhid_set_report_req set_report;
195 struct uhid_set_report_reply_req set_report_reply;
196 struct uhid_start_req start;
197 } u;
198} __attribute__((__packed__));
199
200#endif /* __UHID_H_ */
201

source code of linux/include/uapi/linux/uhid.h