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1/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2/*
3 * User level driver support for input subsystem
4 *
5 * Heavily based on evdev.c by Vojtech Pavlik
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 *
21 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
22 *
23 * Changes/Revisions:
24 * 0.5 08/13/2015 (David Herrmann <dh.herrmann@gmail.com> &
25 * Benjamin Tissoires <benjamin.tissoires@redhat.com>)
26 * - add UI_DEV_SETUP ioctl
27 * - add UI_ABS_SETUP ioctl
28 * - add UI_GET_VERSION ioctl
29 * 0.4 01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
30 * - add UI_GET_SYSNAME ioctl
31 * 0.3 24/05/2006 (Anssi Hannula <anssi.hannulagmail.com>)
32 * - update ff support for the changes in kernel interface
33 * - add UINPUT_VERSION
34 * 0.2 16/10/2004 (Micah Dowty <micah@navi.cx>)
35 * - added force feedback support
36 * - added UI_SET_PHYS
37 * 0.1 20/06/2002
38 * - first public version
39 */
40#ifndef __UINPUT_H_
41#define __UINPUT_H_
42
43#include <linux/types.h>
44#include <linux/input.h>
45
46#define UINPUT_VERSION 5
47#define UINPUT_MAX_NAME_SIZE 80
48
49struct uinput_ff_upload {
50 __u32 request_id;
51 __s32 retval;
52 struct ff_effect effect;
53 struct ff_effect old;
54};
55
56struct uinput_ff_erase {
57 __u32 request_id;
58 __s32 retval;
59 __u32 effect_id;
60};
61
62/* ioctl */
63#define UINPUT_IOCTL_BASE 'U'
64#define UI_DEV_CREATE _IO(UINPUT_IOCTL_BASE, 1)
65#define UI_DEV_DESTROY _IO(UINPUT_IOCTL_BASE, 2)
66
67struct uinput_setup {
68 struct input_id id;
69 char name[UINPUT_MAX_NAME_SIZE];
70 __u32 ff_effects_max;
71};
72
73/**
74 * UI_DEV_SETUP - Set device parameters for setup
75 *
76 * This ioctl sets parameters for the input device to be created. It
77 * supersedes the old "struct uinput_user_dev" method, which wrote this data
78 * via write(). To actually set the absolute axes UI_ABS_SETUP should be
79 * used.
80 *
81 * The ioctl takes a "struct uinput_setup" object as argument. The fields of
82 * this object are as follows:
83 * id: See the description of "struct input_id". This field is
84 * copied unchanged into the new device.
85 * name: This is used unchanged as name for the new device.
86 * ff_effects_max: This limits the maximum numbers of force-feedback effects.
87 * See below for a description of FF with uinput.
88 *
89 * This ioctl can be called multiple times and will overwrite previous values.
90 * If this ioctl fails with -EINVAL, it is recommended to use the old
91 * "uinput_user_dev" method via write() as a fallback, in case you run on an
92 * old kernel that does not support this ioctl.
93 *
94 * This ioctl may fail with -EINVAL if it is not supported or if you passed
95 * incorrect values, -ENOMEM if the kernel runs out of memory or -EFAULT if the
96 * passed uinput_setup object cannot be read/written.
97 * If this call fails, partial data may have already been applied to the
98 * internal device.
99 */
100#define UI_DEV_SETUP _IOW(UINPUT_IOCTL_BASE, 3, struct uinput_setup)
101
102struct uinput_abs_setup {
103 __u16 code; /* axis code */
104 /* __u16 filler; */
105 struct input_absinfo absinfo;
106};
107
108/**
109 * UI_ABS_SETUP - Set absolute axis information for the device to setup
110 *
111 * This ioctl sets one absolute axis information for the input device to be
112 * created. It supersedes the old "struct uinput_user_dev" method, which wrote
113 * part of this data and the content of UI_DEV_SETUP via write().
114 *
115 * The ioctl takes a "struct uinput_abs_setup" object as argument. The fields
116 * of this object are as follows:
117 * code: The corresponding input code associated with this axis
118 * (ABS_X, ABS_Y, etc...)
119 * absinfo: See "struct input_absinfo" for a description of this field.
120 * This field is copied unchanged into the kernel for the
121 * specified axis. If the axis is not enabled via
122 * UI_SET_ABSBIT, this ioctl will enable it.
123 *
124 * This ioctl can be called multiple times and will overwrite previous values.
125 * If this ioctl fails with -EINVAL, it is recommended to use the old
126 * "uinput_user_dev" method via write() as a fallback, in case you run on an
127 * old kernel that does not support this ioctl.
128 *
129 * This ioctl may fail with -EINVAL if it is not supported or if you passed
130 * incorrect values, -ENOMEM if the kernel runs out of memory or -EFAULT if the
131 * passed uinput_setup object cannot be read/written.
132 * If this call fails, partial data may have already been applied to the
133 * internal device.
134 */
135#define UI_ABS_SETUP _IOW(UINPUT_IOCTL_BASE, 4, struct uinput_abs_setup)
136
137#define UI_SET_EVBIT _IOW(UINPUT_IOCTL_BASE, 100, int)
138#define UI_SET_KEYBIT _IOW(UINPUT_IOCTL_BASE, 101, int)
139#define UI_SET_RELBIT _IOW(UINPUT_IOCTL_BASE, 102, int)
140#define UI_SET_ABSBIT _IOW(UINPUT_IOCTL_BASE, 103, int)
141#define UI_SET_MSCBIT _IOW(UINPUT_IOCTL_BASE, 104, int)
142#define UI_SET_LEDBIT _IOW(UINPUT_IOCTL_BASE, 105, int)
143#define UI_SET_SNDBIT _IOW(UINPUT_IOCTL_BASE, 106, int)
144#define UI_SET_FFBIT _IOW(UINPUT_IOCTL_BASE, 107, int)
145#define UI_SET_PHYS _IOW(UINPUT_IOCTL_BASE, 108, char*)
146#define UI_SET_SWBIT _IOW(UINPUT_IOCTL_BASE, 109, int)
147#define UI_SET_PROPBIT _IOW(UINPUT_IOCTL_BASE, 110, int)
148
149#define UI_BEGIN_FF_UPLOAD _IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload)
150#define UI_END_FF_UPLOAD _IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload)
151#define UI_BEGIN_FF_ERASE _IOWR(UINPUT_IOCTL_BASE, 202, struct uinput_ff_erase)
152#define UI_END_FF_ERASE _IOW(UINPUT_IOCTL_BASE, 203, struct uinput_ff_erase)
153
154/**
155 * UI_GET_SYSNAME - get the sysfs name of the created uinput device
156 *
157 * @return the sysfs name of the created virtual input device.
158 * The complete sysfs path is then /sys/devices/virtual/input/--NAME--
159 * Usually, it is in the form "inputN"
160 */
161#define UI_GET_SYSNAME(len) _IOC(_IOC_READ, UINPUT_IOCTL_BASE, 44, len)
162
163/**
164 * UI_GET_VERSION - Return version of uinput protocol
165 *
166 * This writes uinput protocol version implemented by the kernel into
167 * the integer pointed to by the ioctl argument. The protocol version
168 * is hard-coded in the kernel and is independent of the uinput device.
169 */
170#define UI_GET_VERSION _IOR(UINPUT_IOCTL_BASE, 45, unsigned int)
171
172/*
173 * To write a force-feedback-capable driver, the upload_effect
174 * and erase_effect callbacks in input_dev must be implemented.
175 * The uinput driver will generate a fake input event when one of
176 * these callbacks are invoked. The userspace code then uses
177 * ioctls to retrieve additional parameters and send the return code.
178 * The callback blocks until this return code is sent.
179 *
180 * The described callback mechanism is only used if ff_effects_max
181 * is set.
182 *
183 * To implement upload_effect():
184 * 1. Wait for an event with type == EV_UINPUT and code == UI_FF_UPLOAD.
185 * A request ID will be given in 'value'.
186 * 2. Allocate a uinput_ff_upload struct, fill in request_id with
187 * the 'value' from the EV_UINPUT event.
188 * 3. Issue a UI_BEGIN_FF_UPLOAD ioctl, giving it the
189 * uinput_ff_upload struct. It will be filled in with the
190 * ff_effects passed to upload_effect().
191 * 4. Perform the effect upload, and place a return code back into
192 the uinput_ff_upload struct.
193 * 5. Issue a UI_END_FF_UPLOAD ioctl, also giving it the
194 * uinput_ff_upload_effect struct. This will complete execution
195 * of our upload_effect() handler.
196 *
197 * To implement erase_effect():
198 * 1. Wait for an event with type == EV_UINPUT and code == UI_FF_ERASE.
199 * A request ID will be given in 'value'.
200 * 2. Allocate a uinput_ff_erase struct, fill in request_id with
201 * the 'value' from the EV_UINPUT event.
202 * 3. Issue a UI_BEGIN_FF_ERASE ioctl, giving it the
203 * uinput_ff_erase struct. It will be filled in with the
204 * effect ID passed to erase_effect().
205 * 4. Perform the effect erasure, and place a return code back
206 * into the uinput_ff_erase struct.
207 * 5. Issue a UI_END_FF_ERASE ioctl, also giving it the
208 * uinput_ff_erase_effect struct. This will complete execution
209 * of our erase_effect() handler.
210 */
211
212/*
213 * This is the new event type, used only by uinput.
214 * 'code' is UI_FF_UPLOAD or UI_FF_ERASE, and 'value'
215 * is the unique request ID. This number was picked
216 * arbitrarily, above EV_MAX (since the input system
217 * never sees it) but in the range of a 16-bit int.
218 */
219#define EV_UINPUT 0x0101
220#define UI_FF_UPLOAD 1
221#define UI_FF_ERASE 2
222
223struct uinput_user_dev {
224 char name[UINPUT_MAX_NAME_SIZE];
225 struct input_id id;
226 __u32 ff_effects_max;
227 __s32 absmax[ABS_CNT];
228 __s32 absmin[ABS_CNT];
229 __s32 absfuzz[ABS_CNT];
230 __s32 absflat[ABS_CNT];
231};
232#endif /* __UINPUT_H_ */