[Voyageurs] Receive keypress information from the usb keyboard.

sys/voyageurs/xhci/endpoint.h

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <glacier/memory/unique_ptr.h>
+
+#include "xhci/trb_ring.h"
+#include "xhci/xhci.h"
+
+class Endpoint {
+ public:
+  Endpoint() {}
+
+  void Initialize(XhciEndpointContext* context);
+
+  bool Enabled() { return enabled_; }
+
+  void TransferComplete(uint64_t trb_phys);
+
+ private:
+  bool enabled_ = false;
+
+  XhciEndpointContext* context_ = nullptr;
+  glcr::UniquePtr<TrbRingWriter> trb_ring_;
+
+  uint64_t recv_phys_;
+  mmth::OwnedMemoryRegion recv_mem_;
+};