One-KVM/hid/src/main.cpp
2019-10-05 02:42:06 +03:00

220 lines
6.7 KiB
C++

/*****************************************************************************
# #
# KVMD - The main Pi-KVM daemon. #
# #
# Copyright (C) 2018 Maxim Devaev <mdevaev@gmail.com> #
# #
# This program is free software: you can redistribute it and/or modify #
# it under the terms of the GNU General Public License as published by #
# the Free Software Foundation, either version 3 of the License, or #
# (at your option) any later version. #
# #
# This program is distributed in the hope that it will be useful, #
# but WITHOUT ANY WARRANTY; without even the implied warranty of #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
# GNU General Public License for more details. #
# #
# You should have received a copy of the GNU General Public License #
# along with this program. If not, see <https://www.gnu.org/licenses/>. #
# #
*****************************************************************************/
#include <Arduino.h>
#include <HID-Project.h>
#include <TimerOne.h>
#include "inline.h"
#include "keymap.h"
// #define CMD_SERIAL Serial1
#define CMD_SERIAL_SPEED 115200
#define CMD_RECV_TIMEOUT 100000
#define PROTO_MAGIC 0x33
#define PROTO_CRC_POLINOM 0xA001
// -----------------------------------------
#define PROTO_RESP_OK 0x20
#define PROTO_RESP_NONE 0x24
#define PROTO_RESP_CRC_ERROR 0x40
#define PROTO_RESP_INVALID_ERROR 0x45
#define PROTO_RESP_TIMEOUT_ERROR 0x48
// -----------------------------------------
#define PROTO_CMD_PING 0x01
#define PROTO_CMD_REPEAT 0x02
#define PROTO_CMD_RESET_HID 0x10
#define PROTO_CMD_KEY_EVENT 0x11
#define PROTO_CMD_MOUSE_BUTTON_EVENT 0x13 // Legacy sequence
#define PROTO_CMD_MOUSE_MOVE_EVENT 0x12
#define PROTO_CMD_MOUSE_WHEEL_EVENT 0x14
// -----------------------------------------
#define PROTO_CMD_MOUSE_BUTTON_LEFT_SELECT 0b10000000
#define PROTO_CMD_MOUSE_BUTTON_LEFT_STATE 0b00001000
#define PROTO_CMD_MOUSE_BUTTON_RIGHT_SELECT 0b01000000
#define PROTO_CMD_MOUSE_BUTTON_RIGHT_STATE 0b00000100
#define PROTO_CMD_MOUSE_BUTTON_MIDDLE_SELECT 0b00100000
#define PROTO_CMD_MOUSE_BUTTON_MIDDLE_STATE 0b00000010
// -----------------------------------------------------------------------------
INLINE void cmdResetHid(const uint8_t *buffer) { // 0 bytes
BootKeyboard.releaseAll();
SingleAbsoluteMouse.releaseAll();
}
INLINE void cmdKeyEvent(const uint8_t *buffer) { // 2 bytes
KeyboardKeycode code = keymap(buffer[0]);
if (code != KEY_ERROR_UNDEFINED) {
if (buffer[1]) {
BootKeyboard.press(code);
} else {
BootKeyboard.release(code);
}
}
}
INLINE void cmdMouseButtonEvent(const uint8_t *buffer) { // 1 byte
uint8_t state = buffer[0];
# define PROCESS_BUTTON(name) { \
if (state & PROTO_CMD_MOUSE_BUTTON_##name##_SELECT) { \
if (state & PROTO_CMD_MOUSE_BUTTON_##name##_STATE) { \
SingleAbsoluteMouse.press(MOUSE_##name); \
} else { \
SingleAbsoluteMouse.release(MOUSE_##name); \
} \
} \
}
PROCESS_BUTTON(LEFT);
PROCESS_BUTTON(RIGHT);
PROCESS_BUTTON(MIDDLE);
# undef PROCESS_BUTTON
}
INLINE void cmdMouseMoveEvent(const uint8_t *buffer) { // 4 bytes
int x = (int)buffer[0] << 8;
x |= (int)buffer[1];
x = (x + 32768) / 2; // See /kvmd/apps/otg/hid/keyboard.py for details
int y = (int)buffer[2] << 8;
y |= (int)buffer[3];
y = (y + 32768) / 2; // See /kvmd/apps/otg/hid/keyboard.py for details
SingleAbsoluteMouse.moveTo(x, y);
}
INLINE void cmdMouseWheelEvent(const uint8_t *buffer) { // 2 bytes
// delta_x is not supported by hid-project now
signed char delta_y = buffer[1];
SingleAbsoluteMouse.move(0, 0, delta_y);
}
// -----------------------------------------------------------------------------
INLINE uint16_t makeCrc16(const uint8_t *buffer, unsigned length) {
uint16_t crc = 0xFFFF;
for (unsigned byte_count = 0; byte_count < length; ++byte_count) {
crc = crc ^ buffer[byte_count];
for (unsigned bit_count = 0; bit_count < 8; ++bit_count) {
if ((crc & 0x0001) == 0) {
crc = crc >> 1;
} else {
crc = crc >> 1;
crc = crc ^ PROTO_CRC_POLINOM;
}
}
}
return crc;
}
// -----------------------------------------------------------------------------
volatile bool cmd_recv_timed_out = false;
INLINE void recvTimerStop(bool flag) {
Timer1.stop();
cmd_recv_timed_out = flag;
}
INLINE void resetCmdRecvTimeout() {
recvTimerStop(false);
Timer1.initialize(CMD_RECV_TIMEOUT);
}
INLINE void sendCmdResponse(uint8_t code=0) {
static uint8_t prev_code = PROTO_RESP_NONE;
if (code == 0) {
code = prev_code; // Repeat the last code
} else {
prev_code = code;
}
uint8_t buffer[4];
buffer[0] = PROTO_MAGIC;
buffer[1] = code;
uint16_t crc = makeCrc16(buffer, 2);
buffer[2] = (uint8_t)(crc >> 8);
buffer[3] = (uint8_t)(crc & 0xFF);
recvTimerStop(false);
CMD_SERIAL.write(buffer, 4);
}
void intRecvTimedOut() {
recvTimerStop(true);
}
void setup() {
BootKeyboard.begin();
SingleAbsoluteMouse.begin();
Timer1.attachInterrupt(intRecvTimedOut);
CMD_SERIAL.begin(CMD_SERIAL_SPEED);
}
void loop() {
uint8_t buffer[8];
unsigned index = 0;
while (true) {
if (CMD_SERIAL.available() > 0) {
buffer[index] = (uint8_t)CMD_SERIAL.read();
if (index == 7) {
uint16_t crc = (uint16_t)buffer[6] << 8;
crc |= (uint16_t)buffer[7];
if (makeCrc16(buffer, 6) == crc) {
# define HANDLE(_handler) { _handler(buffer + 2); sendCmdResponse(PROTO_RESP_OK); break; }
switch (buffer[1]) {
case PROTO_CMD_RESET_HID: HANDLE(cmdResetHid);
case PROTO_CMD_KEY_EVENT: HANDLE(cmdKeyEvent);
case PROTO_CMD_MOUSE_BUTTON_EVENT: HANDLE(cmdMouseButtonEvent);
case PROTO_CMD_MOUSE_MOVE_EVENT: HANDLE(cmdMouseMoveEvent);
case PROTO_CMD_MOUSE_WHEEL_EVENT: HANDLE(cmdMouseWheelEvent);
case PROTO_CMD_PING: sendCmdResponse(PROTO_RESP_OK); break;
case PROTO_CMD_REPEAT: sendCmdResponse(); break;
default: sendCmdResponse(PROTO_RESP_INVALID_ERROR); break;
}
# undef HANDLE
} else {
sendCmdResponse(PROTO_RESP_CRC_ERROR);
}
index = 0;
} else {
resetCmdRecvTimeout();
index += 1;
}
} else if (index > 0 && cmd_recv_timed_out) {
sendCmdResponse(PROTO_RESP_TIMEOUT_ERROR);
index = 0;
}
}
}