Force Adafruit TinyUSB re-enumeration

Fixes adafruit/Adafruit_TinyUSB_Arduino#400
See also adafruit/Adafruit_TinyUSB_Arduino#454

Author: tttapa

doxygen/pages/MIDI-over-USB.md

@@ -61,7 +61,6 @@ You can also use the [earlephilhower/arduino-pico](https://github.com/earlephilh
 
 Known issues:
  - [ArduinoCore-mbed/issues#129](https://github.com/arduino/ArduinoCore-mbed/issues/129): Nano 33 BLE unreliable USB communication
- - [adafruit/Adafruit_TinyUSB_Arduino#400](https://github.com/adafruit/Adafruit_TinyUSB_Arduino/issues/400): USB descriptors not correctly updated if Bluetooth stack is initialized before Adafruit_TinyUSB
  - [adafruit/Adafruit_TinyUSB_Arduino#238](https://github.com/adafruit/Adafruit_TinyUSB_Arduino/issues/238): TinyUSB MIDI crashes when simultaneously receiving and sending messages
 
 ## Teensy

src/MIDI_Interfaces/USBMIDI/USBMIDI_Adafruit_TinyUSB.hpp

@@ -8,13 +8,21 @@ BEGIN_CS_NAMESPACE
 struct Adafruit_TinyUSB_USBDeviceMIDIBackend {
     using MIDIUSBPacket_t = AH::Array<uint8_t, 4>;
     void begin() {
-#if defined(ARDUINO_ARCH_MBED) && defined(ARDUINO_ARCH_RP2040)
-        // Manual begin() is required on core without built-in support for TinyUSB such as mbed rp2040
-        TinyUSB_Device_Init(0);
-#endif
+        // Manual begin() is required on core without built-in support e.g. mbed rp2040
+        if (!TinyUSBDevice.isInitialized())
+            TinyUSBDevice.begin(0);
         backend.begin();
+        // If already enumerated, additional class driver begin() e.g msc, hid, midi won't take effect until re-enumeration
+        if (TinyUSBDevice.mounted()) {
+            TinyUSBDevice.detach();
+            delay(10);
+            TinyUSBDevice.attach();
+        }
     }
     MIDIUSBPacket_t read() {
+#ifdef TINYUSB_NEED_POLLING_TASK
+        TinyUSBDevice.task();
+#endif
         MIDIUSBPacket_t packet {};
         if (TinyUSBDevice.mounted())
             backend.readPacket(packet.data);