Implemented async USB write

TODO

@@ -79,6 +79,8 @@ Checklist
 
 * check that --quit works, currently broken
 
+* search for "#ifdef FIXME"
+
 
 Stuff to do before 0.7.4 release:
 =================================

src/usb_controller.cpp

@@ -111,8 +111,6 @@ USBController::usb_submit_read(int endpoint, int len)
 {
   assert(!m_read_transfer);
 
-  //log_debug("ep: " << endpoint << " len: " << len);
-
   m_read_transfer = libusb_alloc_transfer(0);
 
   uint8_t* data = static_cast<uint8_t*>(malloc(sizeof(uint8_t) * len));
@@ -130,6 +128,40 @@ USBController::usb_submit_read(int endpoint, int len)
   }
 }
 
+void
+USBController::usb_write(int endpoint, uint8_t* data_in, int len)
+{
+  libusb_transfer* transfer = libusb_alloc_transfer(0);
+  transfer->flags |= LIBUSB_TRANSFER_FREE_BUFFER;
+  transfer->flags |= LIBUSB_TRANSFER_FREE_TRANSFER;
+
+  // copy data into a newly allocated buffer
+  uint8_t* data = static_cast<uint8_t*>(malloc(sizeof(uint8_t) * len));
+  memcpy(data, data_in, len);
+
+  libusb_fill_interrupt_transfer(transfer, m_handle,
+                                 endpoint | LIBUSB_ENDPOINT_OUT,
+                                 data, len,
+                                 &USBController::on_write_data_wrap, this,
+                                 0); // timeout
+
+  int ret;
+  ret = libusb_submit_transfer(transfer);
+  if (ret != LIBUSB_SUCCESS)
+  {
+    raise_exception(std::runtime_error, "libusb_submit_transfer(): " << usb_strerror(ret));
+  }
+}
+
+void
+USBController::on_write_data(libusb_transfer* transfer)
+{
+  if (transfer->status != LIBUSB_TRANSFER_COMPLETED)
+  {
+    log_error("USB write failure: " << transfer->length << ": " << usb_transfer_strerror(transfer->status));
+  }
+}
+
 void
 USBController::usb_cancel_read()
 {
@@ -182,27 +214,6 @@ USBController::usb_release_interface(int ifnum)
   libusb_release_interface(m_handle, ifnum); 
 }
 
-void
-USBController::usb_write(int endpoint, uint8_t* data, int len)
-{
-  log_error("not implemented");
-#ifdef FIXME
-  int transferred = 0;
-  int ret = libusb_interrupt_transfer(m_handle, LIBUSB_ENDPOINT_OUT | endpoint,
-                                      data, len, &transferred, 0);
-  if (ret != LIBUSB_SUCCESS)
-  {
-    raise_exception(std::runtime_error, "libusb_interrupt_transfer() failed: " << usb_strerror(ret));
-  }
-
-  if (transferred != len)
-  {
-    raise_exception(std::runtime_error, "libusb_interrupt_transfer() short write: "
-                    << len << " - " << transferred);
-  }
-#endif
-}
-
 int
 USBController::usb_find_ep(int direction, uint8_t if_class, uint8_t if_subclass, uint8_t if_protocol)
 {

src/usb_controller.hpp

@@ -47,20 +47,29 @@ public:
 
   virtual bool parse(uint8_t* data, int len, XboxGenericMsg* msg_out) =0;
 
+  int  usb_find_ep(int direction, uint8_t if_class, uint8_t if_subclass, uint8_t if_protocol);
+
   void usb_claim_interface(int ifnum, bool try_detach);
   void usb_release_interface(int ifnum);
-  void usb_write(int endpoint, uint8_t* data, int len);
-  int  usb_find_ep(int direction, uint8_t if_class, uint8_t if_subclass, uint8_t if_protocol);
 
   void usb_submit_read(int endpoint, int len);
   void usb_cancel_read();
 
+  void usb_write(int endpoint, uint8_t* data, int len);
+
+private:
   void on_read_data(libusb_transfer *transfer);
   static void on_read_data_wrap(libusb_transfer *transfer)
   {
     static_cast<USBController*>(transfer->user_data)->on_read_data(transfer);
   }
 
+  void on_write_data(libusb_transfer *transfer);
+  static void on_write_data_wrap(libusb_transfer *transfer)
+  {
+    static_cast<USBController*>(transfer->user_data)->on_write_data(transfer);
+  }
+
 private:
   USBController(const USBController&);
   USBController& operator=(const USBController&);

src/usb_helper.cpp

@@ -71,6 +71,21 @@ const char* usb_strerror(int err)
   }
 }
 
+const char* usb_transfer_strerror(libusb_transfer_status err)
+{
+  switch(err)
+  {
+    case LIBUSB_TRANSFER_COMPLETED: return "LIBUSB_TRANSFER_COMPLETED";
+    case LIBUSB_TRANSFER_ERROR: return "LIBUSB_TRANSFER_ERROR";
+    case LIBUSB_TRANSFER_TIMED_OUT: return "LIBUSB_TRANSFER_TIMED_OUT";
+    case LIBUSB_TRANSFER_CANCELLED: return "LIBUSB_TRANSFER_CANCELLED";
+    case LIBUSB_TRANSFER_STALL: return "LIBUSB_TRANSFER_STALL";	
+    case LIBUSB_TRANSFER_NO_DEVICE: return "LIBUSB_TRANSFER_NO_DEVICE";
+    case LIBUSB_TRANSFER_OVERFLOW: return "LIBUSB_TRANSFER_OVERFLOW";
+    default: return "<unknown libusb transfer error code>";
+  }
+}
+
 libusb_device* usb_find_device_by_path(uint8_t busnum, uint8_t devnum)
 {
   libusb_device* ret_device = 0;

src/usb_helper.hpp

@@ -23,6 +23,7 @@
 
 int usb_claim_n_detach_interface(libusb_device_handle* handle, int interface, bool try_detach);
 const char* usb_strerror(int err);
+const char* usb_transfer_strerror(libusb_transfer_status err);
 libusb_device* usb_find_device_by_path(uint8_t busnum, uint8_t devnum);
 
 #endif