fixed usb serial not working after reconnect (#2196)

* fixed usb serial not working after reconnect

* added restart for sd over usb disconnect

* improved usb serial fix

* fixed formatting

firmware/application/usb_serial.cpp

@@ -49,6 +49,7 @@ void USBSerial::on_channel_opened() {
 }
 
 void USBSerial::on_channel_closed() {
+    reset_transfer_queues();
     connected = false;
 }
 

firmware/application/usb_serial_cdc.c

@@ -42,6 +42,10 @@ CH_IRQ_HANDLER(USB0_IRQHandler) {
         chSysUnlockFromIsr();
     }
 
+    if (status & USB0_USBSTS_D_SLI) {
+        on_channel_closed();
+    }
+
     CH_IRQ_EPILOGUE();
 }
 
@@ -131,11 +135,7 @@ usb_request_status_t usb_get_line_coding_request(usb_endpoint_t* const endpoint,
 }
 usb_request_status_t usb_set_control_line_state_request(usb_endpoint_t* const endpoint, const usb_transfer_stage_t stage) {
     if (stage == USB_TRANSFER_STAGE_SETUP) {
-        // if (endpoint->setup.value == 3) {
         on_channel_opened();
-        //} else {
-        //    on_channel_closed();
-        //}
 
         usb_transfer_schedule_ack(endpoint->in);
     }

firmware/application/usb_serial_host_to_device.cpp

@@ -54,6 +54,14 @@ void init_host_to_device() {
     thread_usb_event = chThdSelf();
 }
 
+void reset_transfer_queues() {
+    while (usb_bulk_buffer_queue.empty() == false)
+        usb_bulk_buffer_queue.pop();
+
+    while (usb_bulk_buffer_spare.empty() == false)
+        usb_bulk_buffer_spare.pop();
+}
+
 void schedule_host_to_device_transfer() {
     if (usb_bulk_buffer_queue.size() >= 8)
         return;

firmware/application/usb_serial_host_to_device.hpp

@@ -27,6 +27,7 @@
 #define USB_BULK_BUFFER_SIZE 64
 
 void init_host_to_device();
+void reset_transfer_queues();
 void serial_bulk_transfer_complete(void* user_data, unsigned int bytes_transferred);
 void schedule_host_to_device_transfer();
 void complete_host_to_device_transfer();