serenity/Kernel/Devices/KeyboardDevice.cpp

/*
 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <AK/Assertions.h>
#include <AK/ByteBuffer.h>
#include <AK/Singleton.h>
#include <AK/StringView.h>
#include <AK/Types.h>
#include <Kernel/Arch/i386/CPU.h>
#include <Kernel/Devices/KeyboardDevice.h>
#include <Kernel/IO.h>
#include <Kernel/TTY/VirtualConsole.h>

//#define KEYBOARD_DEBUG

namespace Kernel {

#define IRQ_KEYBOARD 1
#define I8042_BUFFER 0x60
#define I8042_STATUS 0x64
#define I8042_ACK 0xFA
#define I8042_BUFFER_FULL 0x01
#define I8042_WHICH_BUFFER 0x20
#define I8042_MOUSE_BUFFER 0x20
#define I8042_KEYBOARD_BUFFER 0x00

static const KeyCode unshifted_key_map[0x80] = {
    Key_Invalid,
    Key_Escape,
    Key_1,
    Key_2,
    Key_3,
    Key_4,
    Key_5,
    Key_6,
    Key_7,
    Key_8,
    Key_9,
    Key_0,
    Key_Minus,
    Key_Equal,
    Key_Backspace,
    Key_Tab, //15
    Key_Q,
    Key_W,
    Key_E,
    Key_R,
    Key_T,
    Key_Y,
    Key_U,
    Key_I,
    Key_O,
    Key_P,
    Key_LeftBracket,
    Key_RightBracket,
    Key_Return,  // 28
    Key_Control, // 29
    Key_A,
    Key_S,
    Key_D,
    Key_F,
    Key_G,
    Key_H,
    Key_J,
    Key_K,
    Key_L,
    Key_Semicolon,
    Key_Apostrophe,
    Key_Backtick,
    Key_LeftShift, // 42
    Key_Backslash,
    Key_Z,
    Key_X,
    Key_C,
    Key_V,
    Key_B,
    Key_N,
    Key_M,
    Key_Comma,
    Key_Period,
    Key_Slash,
    Key_RightShift, // 54
    Key_Asterisk,
    Key_Alt,      // 56
    Key_Space,    // 57
    Key_CapsLock, // 58
    Key_F1,
    Key_F2,
    Key_F3,
    Key_F4,
    Key_F5,
    Key_F6,
    Key_F7,
    Key_F8,
    Key_F9,
    Key_F10,
    Key_NumLock,
    Key_Invalid, // 70
    Key_Home,
    Key_Up,
    Key_PageUp,
    Key_Minus,
    Key_Left,
    Key_Invalid,
    Key_Right, // 77
    Key_Plus,
    Key_End,
    Key_Down, // 80
    Key_PageDown,
    Key_Invalid,
    Key_Delete, // 83
    Key_Invalid,
    Key_Invalid,
    Key_Backslash,
    Key_F11,
    Key_F12,
    Key_Invalid,
    Key_Invalid,
    Key_Logo,
};

static const KeyCode shifted_key_map[0x100] = {
    Key_Invalid,
    Key_Escape,
    Key_ExclamationPoint,
    Key_AtSign,
    Key_Hashtag,
    Key_Dollar,
    Key_Percent,
    Key_Circumflex,
    Key_Ampersand,
    Key_Asterisk,
    Key_LeftParen,
    Key_RightParen,
    Key_Underscore,
    Key_Plus,
    Key_Backspace,
    Key_Tab,
    Key_Q,
    Key_W,
    Key_E,
    Key_R,
    Key_T,
    Key_Y,
    Key_U,
    Key_I,
    Key_O,
    Key_P,
    Key_LeftBrace,
    Key_RightBrace,
    Key_Return,
    Key_Control,
    Key_A,
    Key_S,
    Key_D,
    Key_F,
    Key_G,
    Key_H,
    Key_J,
    Key_K,
    Key_L,
    Key_Colon,
    Key_DoubleQuote,
    Key_Tilde,
    Key_LeftShift, // 42
    Key_Pipe,
    Key_Z,
    Key_X,
    Key_C,
    Key_V,
    Key_B,
    Key_N,
    Key_M,
    Key_LessThan,
    Key_GreaterThan,
    Key_QuestionMark,
    Key_RightShift, // 54
    Key_Asterisk,
    Key_Alt,
    Key_Space,    // 57
    Key_CapsLock, // 58
    Key_F1,
    Key_F2,
    Key_F3,
    Key_F4,
    Key_F5,
    Key_F6,
    Key_F7,
    Key_F8,
    Key_F9,
    Key_F10,
    Key_NumLock,
    Key_Invalid, // 70
    Key_Home,
    Key_Up,
    Key_PageUp,
    Key_Minus,
    Key_Left,
    Key_Invalid,
    Key_Right, // 77
    Key_Plus,
    Key_End,
    Key_Down, // 80
    Key_PageDown,
    Key_Invalid,
    Key_Delete, // 83
    Key_Invalid,
    Key_Invalid,
    Key_Pipe,
    Key_F11,
    Key_F12,
    Key_Invalid,
    Key_Invalid,
    Key_Logo,
};

static const KeyCode numpad_key_map[13] = { Key_7, Key_8, Key_9, Key_Invalid, Key_4, Key_5, Key_6, Key_Invalid, Key_1, Key_2, Key_3, Key_0, Key_Comma };

void KeyboardDevice::key_state_changed(u8 scan_code, bool pressed)
{
    KeyCode key = (m_modifiers & Mod_Shift) ? shifted_key_map[scan_code] : unshifted_key_map[scan_code];

    if (key == Key_NumLock && pressed)
        m_num_lock_on = !m_num_lock_on;

    if (m_num_lock_on && !m_has_e0_prefix) {
        if (scan_code >= 0x47 && scan_code <= 0x53) {
            u8 index = scan_code - 0x47;
            KeyCode newKey = numpad_key_map[index];

            if (newKey != Key_Invalid) {
                key = newKey;
            }
        }
    }

    if (key == Key_CapsLock && pressed)
        m_caps_lock_on = !m_caps_lock_on;

    Event event;
    event.key = key;
    event.scancode = m_has_e0_prefix ? 0xe000 + scan_code : scan_code;
    event.flags = m_modifiers;
    event.e0_prefix = m_has_e0_prefix;
    event.caps_lock_on = m_caps_lock_on;
    event.code_point = m_character_map.get_char(event);

    if (pressed)
        event.flags |= Is_Press;
    if (m_client)
        m_client->on_key_pressed(event);

    m_queue.enqueue(event);

    m_has_e0_prefix = false;
}

void KeyboardDevice::handle_irq(const RegisterState&)
{
    for (;;) {
        u8 status = IO::in8(I8042_STATUS);
        if (!(((status & I8042_WHICH_BUFFER) == I8042_KEYBOARD_BUFFER) && (status & I8042_BUFFER_FULL)))
            return;
        u8 raw = IO::in8(I8042_BUFFER);
        u8 ch = raw & 0x7f;
        bool pressed = !(raw & 0x80);

        m_entropy_source.add_random_event(raw);

        if (raw == 0xe0) {
            m_has_e0_prefix = true;
            return;
        }

#ifdef KEYBOARD_DEBUG
        dbg() << "Keyboard::handle_irq: " << String::format("%b", ch) << " " << (pressed ? "down" : "up");
#endif
        switch (ch) {
        case 0x38:
            if (m_has_e0_prefix)
                update_modifier(Mod_AltGr, pressed);
            else
                update_modifier(Mod_Alt, pressed);
            break;
        case 0x1d:
            update_modifier(Mod_Ctrl, pressed);
            break;
        case 0x5b:
            update_modifier(Mod_Logo, pressed);
            break;
        case 0x2a:
        case 0x36:
            update_modifier(Mod_Shift, pressed);
            break;
        }
        switch (ch) {
        case I8042_ACK:
            break;
        default:
            if (m_modifiers & Mod_Alt) {
                switch (ch) {
                case 0x02 ... 0x07: // 1 to 6
                    VirtualConsole::switch_to(ch - 0x02);
                    break;
                default:
                    key_state_changed(ch, pressed);
                    break;
                }
            } else {
                key_state_changed(ch, pressed);
            }
        }
    }
}

static AK::Singleton<KeyboardDevice> s_the;

void KeyboardDevice::initialize()
{
    s_the.ensure_instance();
}

KeyboardDevice& KeyboardDevice::the()
{
    return *s_the;
}

KeyboardDevice::KeyboardDevice()
    : IRQHandler(IRQ_KEYBOARD)
    , CharacterDevice(85, 1)
{
    // Empty the buffer of any pending data.
    // I don't care what you've been pressing until now!
    while (IO::in8(I8042_STATUS) & I8042_BUFFER_FULL)
        IO::in8(I8042_BUFFER);

    enable_irq();
}

KeyboardDevice::~KeyboardDevice()
{
}

bool KeyboardDevice::can_read(const FileDescription&, size_t) const
{
    return !m_queue.is_empty();
}

KResultOr<size_t> KeyboardDevice::read(FileDescription&, size_t, UserOrKernelBuffer& buffer, size_t size)
{
    size_t nread = 0;
    while (nread < size) {
        if (m_queue.is_empty())
            break;
        // Don't return partial data frames.
        if ((size - nread) < (ssize_t)sizeof(Event))
            break;
        auto event = m_queue.dequeue();
        ssize_t n = buffer.write_buffered<sizeof(Event)>(sizeof(Event), [&](u8* data, size_t data_bytes) {
            memcpy(data, &event, sizeof(Event));
            return (ssize_t)data_bytes;
        });
        if (n < 0)
            return KResult(n);
        ASSERT((size_t)n == sizeof(Event));
        nread += sizeof(Event);
    }
    return nread;
}

KResultOr<size_t> KeyboardDevice::write(FileDescription&, size_t, const UserOrKernelBuffer&, size_t)
{
    return 0;
}

KeyboardClient::~KeyboardClient()
{
}

void KeyboardDevice::set_maps(const Keyboard::CharacterMapData& character_map_data, const String& character_map_name)
{
    m_character_map.set_character_map_data(character_map_data);
    m_character_map.set_character_map_name(character_map_name);
    dbg() << "New Character map \"" << character_map_name << "\" passing to client.";
}

}