xref: /openbmc/qemu/chardev/msmouse.c (revision ba632924)
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 #include "qemu/osdep.h"
25 #include "qemu-common.h"
26 #include "chardev/char.h"
27 #include "ui/console.h"
28 #include "ui/input.h"
29 
30 #define MSMOUSE_LO6(n) ((n) & 0x3f)
31 #define MSMOUSE_HI2(n) (((n) & 0xc0) >> 6)
32 
33 typedef struct {
34     Chardev parent;
35 
36     QemuInputHandlerState *hs;
37     int axis[INPUT_AXIS__MAX];
38     bool btns[INPUT_BUTTON__MAX];
39     bool btnc[INPUT_BUTTON__MAX];
40     uint8_t outbuf[32];
41     int outlen;
42 } MouseChardev;
43 
44 #define TYPE_CHARDEV_MSMOUSE "chardev-msmouse"
45 #define MOUSE_CHARDEV(obj)                                      \
46     OBJECT_CHECK(MouseChardev, (obj), TYPE_CHARDEV_MSMOUSE)
47 
48 static void msmouse_chr_accept_input(Chardev *chr)
49 {
50     MouseChardev *mouse = MOUSE_CHARDEV(chr);
51     int len;
52 
53     len = qemu_chr_be_can_write(chr);
54     if (len > mouse->outlen) {
55         len = mouse->outlen;
56     }
57     if (!len) {
58         return;
59     }
60 
61     qemu_chr_be_write(chr, mouse->outbuf, len);
62     mouse->outlen -= len;
63     if (mouse->outlen) {
64         memmove(mouse->outbuf, mouse->outbuf + len, mouse->outlen);
65     }
66 }
67 
68 static void msmouse_queue_event(MouseChardev *mouse)
69 {
70     unsigned char bytes[4] = { 0x40, 0x00, 0x00, 0x00 };
71     int dx, dy, count = 3;
72 
73     dx = mouse->axis[INPUT_AXIS_X];
74     mouse->axis[INPUT_AXIS_X] = 0;
75 
76     dy = mouse->axis[INPUT_AXIS_Y];
77     mouse->axis[INPUT_AXIS_Y] = 0;
78 
79     /* Movement deltas */
80     bytes[0] |= (MSMOUSE_HI2(dy) << 2) | MSMOUSE_HI2(dx);
81     bytes[1] |= MSMOUSE_LO6(dx);
82     bytes[2] |= MSMOUSE_LO6(dy);
83 
84     /* Buttons */
85     bytes[0] |= (mouse->btns[INPUT_BUTTON_LEFT]   ? 0x20 : 0x00);
86     bytes[0] |= (mouse->btns[INPUT_BUTTON_RIGHT]  ? 0x10 : 0x00);
87     if (mouse->btns[INPUT_BUTTON_MIDDLE] ||
88         mouse->btnc[INPUT_BUTTON_MIDDLE]) {
89         bytes[3] |= (mouse->btns[INPUT_BUTTON_MIDDLE] ? 0x20 : 0x00);
90         mouse->btnc[INPUT_BUTTON_MIDDLE] = false;
91         count = 4;
92     }
93 
94     if (mouse->outlen <= sizeof(mouse->outbuf) - count) {
95         memcpy(mouse->outbuf + mouse->outlen, bytes, count);
96         mouse->outlen += count;
97     } else {
98         /* queue full -> drop event */
99     }
100 }
101 
102 static void msmouse_input_event(DeviceState *dev, QemuConsole *src,
103                                 InputEvent *evt)
104 {
105     MouseChardev *mouse = MOUSE_CHARDEV(dev);
106     InputMoveEvent *move;
107     InputBtnEvent *btn;
108 
109     switch (evt->type) {
110     case INPUT_EVENT_KIND_REL:
111         move = evt->u.rel.data;
112         mouse->axis[move->axis] += move->value;
113         break;
114 
115     case INPUT_EVENT_KIND_BTN:
116         btn = evt->u.btn.data;
117         mouse->btns[btn->button] = btn->down;
118         mouse->btnc[btn->button] = true;
119         break;
120 
121     default:
122         /* keep gcc happy */
123         break;
124     }
125 }
126 
127 static void msmouse_input_sync(DeviceState *dev)
128 {
129     MouseChardev *mouse = MOUSE_CHARDEV(dev);
130     Chardev *chr = CHARDEV(dev);
131 
132     msmouse_queue_event(mouse);
133     msmouse_chr_accept_input(chr);
134 }
135 
136 static int msmouse_chr_write(struct Chardev *s, const uint8_t *buf, int len)
137 {
138     /* Ignore writes to mouse port */
139     return len;
140 }
141 
142 static void char_msmouse_finalize(Object *obj)
143 {
144     MouseChardev *mouse = MOUSE_CHARDEV(obj);
145 
146     qemu_input_handler_unregister(mouse->hs);
147 }
148 
149 static QemuInputHandler msmouse_handler = {
150     .name  = "QEMU Microsoft Mouse",
151     .mask  = INPUT_EVENT_MASK_BTN | INPUT_EVENT_MASK_REL,
152     .event = msmouse_input_event,
153     .sync  = msmouse_input_sync,
154 };
155 
156 static void msmouse_chr_open(Chardev *chr,
157                              ChardevBackend *backend,
158                              bool *be_opened,
159                              Error **errp)
160 {
161     MouseChardev *mouse = MOUSE_CHARDEV(chr);
162 
163     *be_opened = false;
164     mouse->hs = qemu_input_handler_register((DeviceState *)mouse,
165                                             &msmouse_handler);
166 }
167 
168 static void char_msmouse_class_init(ObjectClass *oc, void *data)
169 {
170     ChardevClass *cc = CHARDEV_CLASS(oc);
171 
172     cc->open = msmouse_chr_open;
173     cc->chr_write = msmouse_chr_write;
174     cc->chr_accept_input = msmouse_chr_accept_input;
175 }
176 
177 static const TypeInfo char_msmouse_type_info = {
178     .name = TYPE_CHARDEV_MSMOUSE,
179     .parent = TYPE_CHARDEV,
180     .instance_size = sizeof(MouseChardev),
181     .instance_finalize = char_msmouse_finalize,
182     .class_init = char_msmouse_class_init,
183 };
184 
185 static void register_types(void)
186 {
187     type_register_static(&char_msmouse_type_info);
188 }
189 
190 type_init(register_types);
191