From 7b42146f332a9d68ca1a56f73771b29a550be66a Mon Sep 17 00:00:00 2001
From: Jesse Buhagiar <jooster669@gmail.com>
Date: Tue, 8 Jun 2021 00:08:41 +1000
Subject: [PATCH] USB: Store devices in globally accessible array

USB Devices are now stored so that they may be later retrieved and
operated on (i.e, fetching their assigned device address via
ProcFS)
---
 Kernel/Devices/USB/UHCIController.cpp | 25 +++++++++++++++++++++++++
 Kernel/Devices/USB/UHCIController.h   |  6 ++++++
 Kernel/Devices/USB/USBDevice.cpp      |  4 ++--
 Kernel/Devices/USB/USBDevice.h        | 10 +++++-----
 4 files changed, 38 insertions(+), 7 deletions(-)

diff --git a/Kernel/Devices/USB/UHCIController.cpp b/Kernel/Devices/USB/UHCIController.cpp
index d11a887789d..e5b3af0cf83 100644
--- a/Kernel/Devices/USB/UHCIController.cpp
+++ b/Kernel/Devices/USB/UHCIController.cpp
@@ -103,6 +103,27 @@ UNMAP_AFTER_INIT UHCIController::~UHCIController()
 {
 }
 
+RefPtr<USB::Device> const UHCIController::get_device_at_port(USB::Device::PortNumber port)
+{
+    if (!m_devices.at(to_underlying(port)))
+        return nullptr;
+
+    return m_devices.at(to_underlying(port));
+}
+
+RefPtr<USB::Device> const UHCIController::get_device_from_address(u8 device_address)
+{
+    for (auto const& device : m_devices) {
+        if (!device)
+            continue;
+
+        if (device->address() == device_address)
+            return device;
+    }
+
+    return nullptr;
+}
+
 void UHCIController::reset()
 {
     stop();
@@ -545,6 +566,8 @@ void UHCIController::spawn_port_proc()
 
                             if (device.is_error())
                                 dmesgln("UHCI: Device creation failed on port 1 ({})", device.error());
+
+                            m_devices.at(0) = device.value();
                         } else {
                             dmesgln("UHCI: Device detach detected on Root Port 1");
                         }
@@ -575,6 +598,8 @@ void UHCIController::spawn_port_proc()
 
                             if (device.is_error())
                                 dmesgln("UHCI: Device creation failed on port 2 ({})", device.error());
+
+                            m_devices.at(1) = device.value();
                         } else {
                             dmesgln("UHCI: Device detach detected on Root Port 2");
                         }
diff --git a/Kernel/Devices/USB/UHCIController.h b/Kernel/Devices/USB/UHCIController.h
index 8ebbc907989..97318773721 100644
--- a/Kernel/Devices/USB/UHCIController.h
+++ b/Kernel/Devices/USB/UHCIController.h
@@ -26,6 +26,7 @@ class UHCIController final : public PCI::Device {
 public:
     static void detect();
     static UHCIController& the();
+
     virtual ~UHCIController() override;
 
     virtual const char* purpose() const override { return "UHCI"; }
@@ -39,6 +40,9 @@ public:
 
     KResultOr<size_t> submit_control_transfer(Transfer& transfer);
 
+    RefPtr<USB::Device> const get_device_at_port(USB::Device::PortNumber);
+    RefPtr<USB::Device> const get_device_from_address(u8 device_address);
+
 private:
     UHCIController(PCI::Address, PCI::ID);
 
@@ -89,6 +93,8 @@ private:
     OwnPtr<Region> m_framelist;
     OwnPtr<Region> m_qh_pool;
     OwnPtr<Region> m_td_pool;
+
+    Array<RefPtr<USB::Device>, 2> m_devices; // Devices connected to the root ports (of which there are two)
 };
 
 }
diff --git a/Kernel/Devices/USB/USBDevice.cpp b/Kernel/Devices/USB/USBDevice.cpp
index b13f568a3af..fcb5773a81f 100644
--- a/Kernel/Devices/USB/USBDevice.cpp
+++ b/Kernel/Devices/USB/USBDevice.cpp
@@ -16,13 +16,13 @@ static u32 s_next_usb_address = 1; // Next address we hand out to a device once
 
 namespace Kernel::USB {
 
-KResultOr<NonnullOwnPtr<Device>> Device::try_create(PortNumber port, DeviceSpeed speed)
+KResultOr<NonnullRefPtr<Device>> Device::try_create(PortNumber port, DeviceSpeed speed)
 {
     auto pipe_or_error = Pipe::try_create_pipe(Pipe::Type::Control, Pipe::Direction::Bidirectional, 0, 8, 0);
     if (pipe_or_error.is_error())
         return pipe_or_error.error();
 
-    auto device = adopt_own_if_nonnull(new Device(port, speed, pipe_or_error.release_value()));
+    auto device = adopt_ref_if_nonnull(new Device(port, speed, pipe_or_error.release_value()));
     if (!device)
         return ENOMEM;
 
diff --git a/Kernel/Devices/USB/USBDevice.h b/Kernel/Devices/USB/USBDevice.h
index 8b08d9552df..bcf95a4dcbb 100644
--- a/Kernel/Devices/USB/USBDevice.h
+++ b/Kernel/Devices/USB/USBDevice.h
@@ -17,7 +17,7 @@ namespace Kernel::USB {
 // glues together:
 //
 // https://www.ftdichip.com/Support/Documents/TechnicalNotes/TN_113_Simplified%20Description%20of%20USB%20Device%20Enumeration.pdf
-class Device {
+class Device : public RefCounted<Device> {
 public:
     enum class PortNumber : u8 {
         Port1 = 0,
@@ -30,8 +30,7 @@ public:
     };
 
 public:
-    static KResultOr<NonnullOwnPtr<Device>> try_create(PortNumber, DeviceSpeed);
-    static Device* get(PortNumber);
+    static KResultOr<NonnullRefPtr<Device>> try_create(PortNumber, DeviceSpeed);
 
     Device(PortNumber, DeviceSpeed, NonnullOwnPtr<Pipe> default_pipe);
     ~Device();
@@ -50,8 +49,9 @@ private:
     u8 m_address { 0 };         // USB address assigned to this device
 
     // Device description
-    u16 m_vendor_id { 0 };  // This device's vendor ID assigned by the USB group
-    u16 m_product_id { 0 }; // This device's product ID assigned by the USB group
+    u16 m_vendor_id { 0 };                   // This device's vendor ID assigned by the USB group
+    u16 m_product_id { 0 };                  // This device's product ID assigned by the USB group
+    USBDeviceDescriptor m_device_descriptor; // Device Descriptor obtained from USB Device
 
     NonnullOwnPtr<Pipe> m_default_pipe; // Default communication pipe (endpoint0) used during enumeration
 };