Kernel: Introduce a new HID subsystem

The end goal of this commit is to allow to boot on bare metal with no PS/2 device connected to the system. It turned out that the original code relied on the existence of the PS/2 keyboard, so VirtualConsole called it even though ACPI indicated the there's no i8042 controller on my real machine because I didn't plug any PS/2 device. The code is much more flexible, so adding HID support for other type of hardware (e.g. USB HID) could be much simpler. Briefly describing the change, we have a new singleton called HIDManagement, which is responsible to initialize the i8042 controller if exists, and to enumerate its devices. I also abstracted a bit things, so now every Human interface device is represented with the HIDDevice class. Then, there are 2 types of it - the MouseDevice and KeyboardDevice classes; both are responsible to handle the interface in the DevFS. PS2KeyboardDevice, PS2MouseDevice and VMWareMouseDevice classes are responsible for handling the hardware-specific interface they are assigned to. Therefore, they are inheriting from the IRQHandler class.
2025-07-25 07:27:45 +00:00 · 2021-04-02 23:21:35 +03:00 · 2021-04-02 23:21:35 +03:00 · 8e3e3a71cb
commit 8e3e3a71cb
parent 32dd9c554b
23 changed files with 942 additions and 410 deletions
--- a/Kernel/Devices/HID/PS2KeyboardDevice.cpp
+++ b/Kernel/Devices/HID/PS2KeyboardDevice.cpp
@ -0,0 +1,133 @@
+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
+ * 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/x86/CPU.h>
+#include <Kernel/Debug.h>
+#include <Kernel/Devices/HID/HIDManagement.h>
+#include <Kernel/Devices/HID/PS2KeyboardDevice.h>
+#include <Kernel/IO.h>
+#include <Kernel/TTY/VirtualConsole.h>
+
+namespace Kernel {
+
+#define IRQ_KEYBOARD 1
+
+void PS2KeyboardDevice::irq_handle_byte_read(u8 byte)
+{
+    u8 ch = byte & 0x7f;
+    bool pressed = !(byte & 0x80);
+
+    m_entropy_source.add_random_event(byte);
+
+    if (byte == 0xe0) {
+        m_has_e0_prefix = true;
+        return;
+    }
+
+    dbgln_if(KEYBOARD_DEBUG, "Keyboard::irq_handle_byte_read: {:#02x} {}", ch, (pressed ? "down" : "up"));
+    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_Super, 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);
+        }
+    }
+}
+
+void PS2KeyboardDevice::handle_irq(const RegisterState&)
+{
+    // The controller will read the data and call irq_handle_byte_read
+    // for the appropriate device
+    m_i8042_controller->irq_process_input_buffer(HIDDevice::Type::Keyboard);
+}
+
+UNMAP_AFTER_INIT RefPtr<PS2KeyboardDevice> PS2KeyboardDevice::try_to_initialize(const I8042Controller& ps2_controller)
+{
+    auto device = adopt(*new PS2KeyboardDevice(ps2_controller));
+    if (device->initialize())
+        return device;
+    return nullptr;
+}
+
+UNMAP_AFTER_INIT bool PS2KeyboardDevice::initialize()
+{
+    if (!m_i8042_controller->reset_device(HIDDevice::Type::Keyboard)) {
+        dbgln("KeyboardDevice: I8042 controller failed to reset device");
+        return false;
+    }
+    return true;
+}
+
+// FIXME: UNMAP_AFTER_INIT might not be correct, because in practice PS/2 devices
+// are hot pluggable.
+UNMAP_AFTER_INIT PS2KeyboardDevice::PS2KeyboardDevice(const I8042Controller& ps2_controller)
+    : IRQHandler(IRQ_KEYBOARD)
+    , KeyboardDevice()
+    , I8042Device(ps2_controller)
+{
+}
+
+// FIXME: UNMAP_AFTER_INIT might not be correct, because in practice PS/2 devices
+// are hot pluggable.
+UNMAP_AFTER_INIT PS2KeyboardDevice::~PS2KeyboardDevice()
+{
+}
+
+}