xref: /openbmc/qemu/chardev/msmouse.c (revision f363d039)
1 /*
2  * QEMU Microsoft serial mouse emulation
3  *
4  * Copyright (c) 2008 Lubomir Rintel
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 #include "qemu/osdep.h"
26 #include "qemu/module.h"
27 #include "chardev/char.h"
28 #include "ui/console.h"
29 #include "ui/input.h"
30 
31 #define MSMOUSE_LO6(n) ((n) & 0x3f)
32 #define MSMOUSE_HI2(n) (((n) & 0xc0) >> 6)
33 
34 typedef struct {
35     Chardev parent;
36 
37     QemuInputHandlerState *hs;
38     int axis[INPUT_AXIS__MAX];
39     bool btns[INPUT_BUTTON__MAX];
40     bool btnc[INPUT_BUTTON__MAX];
41     uint8_t outbuf[32];
42     int outlen;
43 } MouseChardev;
44 
45 #define TYPE_CHARDEV_MSMOUSE "chardev-msmouse"
46 #define MOUSE_CHARDEV(obj)                                      \
47     OBJECT_CHECK(MouseChardev, (obj), TYPE_CHARDEV_MSMOUSE)
48 
49 static void msmouse_chr_accept_input(Chardev *chr)
50 {
51     MouseChardev *mouse = MOUSE_CHARDEV(chr);
52     int len;
53 
54     len = qemu_chr_be_can_write(chr);
55     if (len > mouse->outlen) {
56         len = mouse->outlen;
57     }
58     if (!len) {
59         return;
60     }
61 
62     qemu_chr_be_write(chr, mouse->outbuf, len);
63     mouse->outlen -= len;
64     if (mouse->outlen) {
65         memmove(mouse->outbuf, mouse->outbuf + len, mouse->outlen);
66     }
67 }
68 
69 static void msmouse_queue_event(MouseChardev *mouse)
70 {
71     unsigned char bytes[4] = { 0x40, 0x00, 0x00, 0x00 };
72     int dx, dy, count = 3;
73 
74     dx = mouse->axis[INPUT_AXIS_X];
75     mouse->axis[INPUT_AXIS_X] = 0;
76 
77     dy = mouse->axis[INPUT_AXIS_Y];
78     mouse->axis[INPUT_AXIS_Y] = 0;
79 
80     /* Movement deltas */
81     bytes[0] |= (MSMOUSE_HI2(dy) << 2) | MSMOUSE_HI2(dx);
82     bytes[1] |= MSMOUSE_LO6(dx);
83     bytes[2] |= MSMOUSE_LO6(dy);
84 
85     /* Buttons */
86     bytes[0] |= (mouse->btns[INPUT_BUTTON_LEFT]   ? 0x20 : 0x00);
87     bytes[0] |= (mouse->btns[INPUT_BUTTON_RIGHT]  ? 0x10 : 0x00);
88     if (mouse->btns[INPUT_BUTTON_MIDDLE] ||
89         mouse->btnc[INPUT_BUTTON_MIDDLE]) {
90         bytes[3] |= (mouse->btns[INPUT_BUTTON_MIDDLE] ? 0x20 : 0x00);
91         mouse->btnc[INPUT_BUTTON_MIDDLE] = false;
92         count = 4;
93     }
94 
95     if (mouse->outlen <= sizeof(mouse->outbuf) - count) {
96         memcpy(mouse->outbuf + mouse->outlen, bytes, count);
97         mouse->outlen += count;
98     } else {
99         /* queue full -> drop event */
100     }
101 }
102 
103 static void msmouse_input_event(DeviceState *dev, QemuConsole *src,
104                                 InputEvent *evt)
105 {
106     MouseChardev *mouse = MOUSE_CHARDEV(dev);
107     InputMoveEvent *move;
108     InputBtnEvent *btn;
109 
110     switch (evt->type) {
111     case INPUT_EVENT_KIND_REL:
112         move = evt->u.rel.data;
113         mouse->axis[move->axis] += move->value;
114         break;
115 
116     case INPUT_EVENT_KIND_BTN:
117         btn = evt->u.btn.data;
118         mouse->btns[btn->button] = btn->down;
119         mouse->btnc[btn->button] = true;
120         break;
121 
122     default:
123         /* keep gcc happy */
124         break;
125     }
126 }
127 
128 static void msmouse_input_sync(DeviceState *dev)
129 {
130     MouseChardev *mouse = MOUSE_CHARDEV(dev);
131     Chardev *chr = CHARDEV(dev);
132 
133     msmouse_queue_event(mouse);
134     msmouse_chr_accept_input(chr);
135 }
136 
137 static int msmouse_chr_write(struct Chardev *s, const uint8_t *buf, int len)
138 {
139     /* Ignore writes to mouse port */
140     return len;
141 }
142 
143 static void char_msmouse_finalize(Object *obj)
144 {
145     MouseChardev *mouse = MOUSE_CHARDEV(obj);
146 
147     qemu_input_handler_unregister(mouse->hs);
148 }
149 
150 static QemuInputHandler msmouse_handler = {
151     .name  = "QEMU Microsoft Mouse",
152     .mask  = INPUT_EVENT_MASK_BTN | INPUT_EVENT_MASK_REL,
153     .event = msmouse_input_event,
154     .sync  = msmouse_input_sync,
155 };
156 
157 static void msmouse_chr_open(Chardev *chr,
158                              ChardevBackend *backend,
159                              bool *be_opened,
160                              Error **errp)
161 {
162     MouseChardev *mouse = MOUSE_CHARDEV(chr);
163 
164     *be_opened = false;
165     mouse->hs = qemu_input_handler_register((DeviceState *)mouse,
166                                             &msmouse_handler);
167 }
168 
169 static void char_msmouse_class_init(ObjectClass *oc, void *data)
170 {
171     ChardevClass *cc = CHARDEV_CLASS(oc);
172 
173     cc->open = msmouse_chr_open;
174     cc->chr_write = msmouse_chr_write;
175     cc->chr_accept_input = msmouse_chr_accept_input;
176 }
177 
178 static const TypeInfo char_msmouse_type_info = {
179     .name = TYPE_CHARDEV_MSMOUSE,
180     .parent = TYPE_CHARDEV,
181     .instance_size = sizeof(MouseChardev),
182     .instance_finalize = char_msmouse_finalize,
183     .class_init = char_msmouse_class_init,
184 };
185 
186 static void register_types(void)
187 {
188     type_register_static(&char_msmouse_type_info);
189 }
190 
191 type_init(register_types);
192