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Serenity Operating System
1/*
2 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice, this
9 * list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#include <AK/Memory.h>
28#include <Kernel/Devices/PS2MouseDevice.h>
29#include <Kernel/Devices/VMWareBackdoor.h>
30#include <LibBareMetal/IO.h>
31
32namespace Kernel {
33
34#define IRQ_MOUSE 12
35#define I8042_BUFFER 0x60
36#define I8042_STATUS 0x64
37#define I8042_ACK 0xFA
38#define I8042_BUFFER_FULL 0x01
39#define I8042_WHICH_BUFFER 0x20
40#define I8042_MOUSE_BUFFER 0x20
41#define I8042_KEYBOARD_BUFFER 0x00
42
43#define PS2MOUSE_SET_RESOLUTION 0xE8
44#define PS2MOUSE_STATUS_REQUEST 0xE9
45#define PS2MOUSE_REQUEST_SINGLE_PACKET 0xEB
46#define PS2MOUSE_GET_DEVICE_ID 0xF2
47#define PS2MOUSE_SET_SAMPLE_RATE 0xF3
48#define PS2MOUSE_ENABLE_PACKET_STREAMING 0xF4
49#define PS2MOUSE_DISABLE_PACKET_STREAMING 0xF5
50#define PS2MOUSE_SET_DEFAULTS 0xF6
51#define PS2MOUSE_RESEND 0xFE
52#define PS2MOUSE_RESET 0xFF
53
54#define PS2MOUSE_INTELLIMOUSE_ID 0x03
55
56//#define PS2MOUSE_DEBUG
57
58static PS2MouseDevice* s_the;
59
60PS2MouseDevice::PS2MouseDevice()
61 : IRQHandler(IRQ_MOUSE)
62 , CharacterDevice(10, 1)
63{
64 s_the = this;
65 initialize();
66}
67
68PS2MouseDevice::~PS2MouseDevice()
69{
70}
71
72PS2MouseDevice& PS2MouseDevice::the()
73{
74 return *s_the;
75}
76
77void PS2MouseDevice::handle_irq(const RegisterState&)
78{
79 if (auto* backdoor = VMWareBackdoor::the()) {
80 if (backdoor->vmmouse_is_absolute()) {
81 IO::in8(I8042_BUFFER);
82 auto packet = backdoor->receive_mouse_packet();
83 if (packet.has_value())
84 m_queue.enqueue(packet.value());
85 return;
86 }
87 }
88 for (;;) {
89 u8 status = IO::in8(I8042_STATUS);
90 if (!(((status & I8042_WHICH_BUFFER) == I8042_MOUSE_BUFFER) && (status & I8042_BUFFER_FULL)))
91 return;
92
93 u8 data = IO::in8(I8042_BUFFER);
94 m_data[m_data_state] = data;
95
96 auto commit_packet = [&] {
97 m_data_state = 0;
98#ifdef PS2MOUSE_DEBUG
99 dbg() << "PS2Mouse: " << m_data[1] << ", " << m_data[2] << " " << ((m_data[0] & 1) ? "Left" : "") << " " << ((m_data[0] & 2) ? "Right" : "") << " (buffered: " << m_queue.size() << ")";
100#endif
101 parse_data_packet();
102 };
103
104 switch (m_data_state) {
105 case 0:
106 if (!(data & 0x08)) {
107 dbg() << "PS2Mouse: Stream out of sync.";
108 break;
109 }
110 ++m_data_state;
111 break;
112 case 1:
113 ++m_data_state;
114 break;
115 case 2:
116 if (m_has_wheel) {
117 ++m_data_state;
118 break;
119 }
120 commit_packet();
121 break;
122 case 3:
123 ASSERT(m_has_wheel);
124 commit_packet();
125 break;
126 }
127 }
128}
129
130void PS2MouseDevice::parse_data_packet()
131{
132 int x = m_data[1];
133 int y = m_data[2];
134 int z = 0;
135 if (m_has_wheel)
136 z = (char)m_data[3];
137 bool x_overflow = m_data[0] & 0x40;
138 bool y_overflow = m_data[0] & 0x80;
139 bool x_sign = m_data[0] & 0x10;
140 bool y_sign = m_data[0] & 0x20;
141 if (x && x_sign)
142 x -= 0x100;
143 if (y && y_sign)
144 y -= 0x100;
145 if (x_overflow || y_overflow) {
146 x = 0;
147 y = 0;
148 }
149 MousePacket packet;
150 packet.x = x;
151 packet.y = y;
152 packet.z = z;
153 packet.buttons = m_data[0] & 0x07;
154 packet.is_relative = true;
155#ifdef PS2MOUSE_DEBUG
156 dbg() << "PS2 Relative Mouse: Buttons " << String::format("%x", packet.buttons);
157 dbg() << "Mouse: X " << packet.x << ", Y " << packet.y << ", Z " << packet.z;
158#endif
159 m_queue.enqueue(packet);
160}
161
162void PS2MouseDevice::wait_then_write(u8 port, u8 data)
163{
164 prepare_for_output();
165 IO::out8(port, data);
166}
167
168u8 PS2MouseDevice::wait_then_read(u8 port)
169{
170 prepare_for_input();
171 return IO::in8(port);
172}
173
174void PS2MouseDevice::initialize()
175{
176 // Enable PS aux port
177 wait_then_write(I8042_STATUS, 0xa8);
178
179 check_device_presence();
180
181 if (m_device_present)
182 initialize_device();
183}
184
185void PS2MouseDevice::check_device_presence()
186{
187 mouse_write(PS2MOUSE_REQUEST_SINGLE_PACKET);
188 u8 maybe_ack = mouse_read();
189 if (maybe_ack == I8042_ACK) {
190 m_device_present = true;
191 klog() << "PS2MouseDevice: Device detected";
192
193 // the mouse will send a packet of data, since that's what we asked
194 // for. we don't care about the content.
195 mouse_read();
196 mouse_read();
197 mouse_read();
198 } else {
199 m_device_present = false;
200 klog() << "PS2MouseDevice: Device not detected";
201 }
202}
203
204void PS2MouseDevice::initialize_device()
205{
206 if (!m_device_present)
207 return;
208
209 // Enable interrupts
210 wait_then_write(I8042_STATUS, 0x20);
211
212 // Enable the PS/2 mouse IRQ (12).
213 // NOTE: The keyboard uses IRQ 1 (and is enabled by bit 0 in this register).
214 u8 status = wait_then_read(I8042_BUFFER) | 2;
215 wait_then_write(I8042_STATUS, 0x60);
216 wait_then_write(I8042_BUFFER, status);
217
218 // Set default settings.
219 mouse_write(PS2MOUSE_SET_DEFAULTS);
220 expect_ack();
221
222 // Enable.
223 mouse_write(PS2MOUSE_ENABLE_PACKET_STREAMING);
224 expect_ack();
225
226 mouse_write(PS2MOUSE_GET_DEVICE_ID);
227 expect_ack();
228 u8 device_id = mouse_read();
229
230 if (device_id != PS2MOUSE_INTELLIMOUSE_ID) {
231 // Send magical wheel initiation sequence.
232 mouse_write(PS2MOUSE_SET_SAMPLE_RATE);
233 expect_ack();
234 mouse_write(200);
235 expect_ack();
236 mouse_write(PS2MOUSE_SET_SAMPLE_RATE);
237 expect_ack();
238 mouse_write(100);
239 expect_ack();
240 mouse_write(PS2MOUSE_SET_SAMPLE_RATE);
241 expect_ack();
242 mouse_write(80);
243 expect_ack();
244
245 mouse_write(PS2MOUSE_GET_DEVICE_ID);
246 expect_ack();
247 device_id = mouse_read();
248 }
249
250 if (device_id == PS2MOUSE_INTELLIMOUSE_ID) {
251 m_has_wheel = true;
252 klog() << "PS2MouseDevice: Mouse wheel enabled!";
253 } else {
254 klog() << "PS2MouseDevice: No mouse wheel detected!";
255 }
256
257 enable_irq();
258}
259
260void PS2MouseDevice::expect_ack()
261{
262 u8 data = mouse_read();
263 ASSERT(data == I8042_ACK);
264}
265
266void PS2MouseDevice::prepare_for_input()
267{
268 for (;;) {
269 if (IO::in8(I8042_STATUS) & 1)
270 return;
271 }
272}
273
274void PS2MouseDevice::prepare_for_output()
275{
276 for (;;) {
277 if (!(IO::in8(I8042_STATUS) & 2))
278 return;
279 }
280}
281
282void PS2MouseDevice::mouse_write(u8 data)
283{
284 prepare_for_output();
285 IO::out8(I8042_STATUS, 0xd4);
286 prepare_for_output();
287 IO::out8(I8042_BUFFER, data);
288}
289
290u8 PS2MouseDevice::mouse_read()
291{
292 prepare_for_input();
293 return IO::in8(I8042_BUFFER);
294}
295
296bool PS2MouseDevice::can_read(const FileDescription&) const
297{
298 return !m_queue.is_empty();
299}
300
301ssize_t PS2MouseDevice::read(FileDescription&, u8* buffer, ssize_t size)
302{
303 ASSERT(size > 0);
304 size_t nread = 0;
305 size_t remaining_space_in_buffer = static_cast<size_t>(size) - nread;
306 while (!m_queue.is_empty() && remaining_space_in_buffer) {
307 auto packet = m_queue.dequeue();
308#ifdef PS2MOUSE_DEBUG
309 dbg() << "PS2 Mouse Read: Buttons " << String::format("%x", packet.buttons);
310 dbg() << "PS2 Mouse: X " << packet.x << ", Y " << packet.y << ", Z " << packet.z << " Relative " << packet.buttons;
311 dbg() << "PS2 Mouse Read: Filter packets";
312#endif
313 size_t bytes_read_from_packet = min(remaining_space_in_buffer, sizeof(MousePacket));
314 memcpy(buffer + nread, &packet, bytes_read_from_packet);
315 nread += bytes_read_from_packet;
316 remaining_space_in_buffer -= bytes_read_from_packet;
317 }
318 return nread;
319}
320
321ssize_t PS2MouseDevice::write(FileDescription&, const u8*, ssize_t)
322{
323 return 0;
324}
325
326}