samd: Enable support for Python USB devices.

This work was funded through GitHub Sponsors.

Signed-off-by: Angus Gratton <angus@redyak.com.au>

ports/samd/Makefile

@@ -136,6 +136,7 @@ SHARED_SRC_C += \
 	shared/tinyusb/mp_cdc_common.c \
 	shared/tinyusb/mp_usbd.c \
 	shared/tinyusb/mp_usbd_descriptor.c \
+	shared/tinyusb/mp_usbd_runtime.c \
 
 ASF4_SRC_C += $(addprefix lib/asf4/$(MCU_SERIES_LOWER)/,\
 	hal/src/hal_atomic.c \

ports/samd/main.c

@@ -93,6 +93,9 @@ void samd_main(void) {
         pwm_deinit_all();
         #endif
         soft_timer_deinit();
+        #if MICROPY_HW_ENABLE_USB_RUNTIME_DEVICE
+        mp_usbd_deinit();
+        #endif
         gc_sweep_all();
         #if MICROPY_PY_MACHINE_I2C || MICROPY_PY_MACHINE_SPI || MICROPY_PY_MACHINE_UART
         sercom_deinit_all();

ports/samd/mpconfigport.h

@@ -63,8 +63,13 @@
 #ifndef MICROPY_HW_USB_DESC_STR_MAX
 #define MICROPY_HW_USB_DESC_STR_MAX (32)
 #endif
+// Support machine.USBDevice
+#ifndef MICROPY_HW_ENABLE_USB_RUNTIME_DEVICE
+#define MICROPY_HW_ENABLE_USB_RUNTIME_DEVICE    (1)
 #endif
 
+#endif // MICROPY_HW_ENABLE_USBDEV
+
 #define MICROPY_PY_SYS_PLATFORM             "samd"
 
 // Extended modules