feat: add RTL-SDR, R820t drivers, radio APIs, and sdr demo tool

kernel/src/Drivers/USB/Xhci.hpp

@@ -320,6 +320,12 @@ namespace Drivers::USB::Xhci {
     // pipe (e.g. during Bluetooth firmware download).
     void ResetInterruptEndpoint(uint8_t slotId);
 
+    // Clear a halted bulk IN endpoint (Reset Endpoint + Set TR Dequeue) without
+    // re-arming.  Must be called from process context (it issues commands that
+    // wait on the event ring); the caller re-arms with QueueBulkInTransfer.
+    // Used for SDR stream stall recovery (RTL2832 bulk IN can STALL on start).
+    void ResetBulkInEndpoint(uint8_t slotId);
+
     // True while PollEvents() is draining the event ring.  A command submitter
     // reached from inside an event callback must fire-and-forget (not wait),
     // since a nested PollEvents() is a no-op.
@@ -329,6 +335,19 @@ namespace Drivers::USB::Xhci {
     void QueueBulkInTransfer(uint8_t slotId, uint8_t* data, uint64_t dataPhys, uint32_t length);
     void QueueBulkOutTransfer(uint8_t slotId, uint8_t* data, uint64_t dataPhys, uint32_t length);
 
+    // Continuous multi-buffer bulk-IN streaming.  StartBulkInStream allocates
+    // `numBuffers` (clamped to 16) DMA buffers of `xferLen` bytes (clamped to a
+    // 4 KiB page) and keeps that many transfers outstanding, auto-re-arming each
+    // as it completes.  The slot's registered transfer callback receives every
+    // buffer's data but must NOT re-arm itself (the event handler does).  This
+    // eliminates the FIFO-overflow gap of single-outstanding bulk IN.  Use for
+    // sustained high-rate sources (RTL-SDR I/Q).  PrimeBulkInStream re-queues the
+    // whole pool after a stall reset; StopBulkInStream disarms the rotation.
+    // All three are process-context calls.
+    void StartBulkInStream(uint8_t slotId, uint32_t xferLen, uint32_t numBuffers);
+    void PrimeBulkInStream(uint8_t slotId);
+    void StopBulkInStream(uint8_t slotId);
+
     // Queue a bulk transfer and wait for its completion. Used by storage-style
     // class drivers that need command/response ordering on bulk pipes.
     uint32_t BulkTransfer(uint8_t slotId, bool dirIn, void* data, uint64_t dataPhys,