Improve error handling at timeout

Set state to USB_TYPE_IDLE to allow recover from the error, but return the error. The
previous solution didn't correctly report all errors.

Author: Alrik Vidstrom

src/USBHost/USBHost.cpp

@@ -1145,6 +1145,8 @@ USB_TYPE USBHost::generalTransfer(USBDeviceConnected * dev, USBEndpoint * ep, ui
         USB_DBG_TRANSFER("%s TRANSFER res: %s on ep: %p\r\n", type_str, ep->getStateString(), ep);
 
         if (res != USB_TYPE_IDLE) {
+            // Set state to USB_TYPE_IDLE to allow recover from the error, but return the error
+            ep->setState(USB_TYPE_IDLE);
             return res;
         }
 

src/targets/TARGET_STM/USBEndpoint_STM.cpp

@@ -153,11 +153,6 @@ void USBEndpoint::setState(USB_TYPE st)
         USBx_HC(hced->ch_num)->HCCHAR &= ~USB_OTG_HCCHAR_CHDIS;
         USBx_HC(hced->ch_num)->HCCHAR |= USB_OTG_HCCHAR_CHENA;
         // <--
-        // Set state to USB_TYPE_IDLE to allow the library to recover from the error.
-        // WARNING: This might lead to some errors going unreported, and should be improved in the future, but
-        //          at least the library passes all our tests from higher levels at this point, which it didn't
-        //          do before.
-        state = USB_TYPE_IDLE;
     }
 }