STM32: (Original/Pico/WiFi) if USB connected but PC not receiving dat…

…a, throw away USB data rather than blocking (fix #2446)

ChangeLog

@@ -18,6 +18,7 @@
             Fix lock leak when using flat/flash/native strings as object indices
             Fix g.wrapString lockup if wrap width is less than the character width
             Fix potential for crash after ReferenceError during function declaration (fix #2457)
+            STM32: (Original/Pico/WiFi) if USB connected but PC not receiving data, throw away USB data rather than blocking (fix #2446)
 
      2v20 : Ensure String.charCodeAt returns NaN for out of bounds chars
             Bangle.js2: When rendering overlays, *do not* use the current FG/BG color for 1 bit overlays

src/jshardware.h

@@ -425,6 +425,8 @@ void jshSetupRTCPrescalerValue(unsigned int prescale);
 int jshGetRTCPrescalerValue(bool calibrate);
 // Reset timers and average systick duration counters for RTC - when coming out of sleep or changing prescaler
 void jshResetRTCTimer();
+/// Flags that we've been able to send data down USB, so it's ok to have data in the output buffer
+void jshClearUSBIdleTimeout();
 #endif
 
 #if defined(NRF51_SERIES) || defined(NRF52_SERIES)

targetlibs/stm32legacyusb/usb_endp.c

@@ -16,8 +16,8 @@
   *
   *        http://www.st.com/software_license_agreement_liberty_v2
   *
-  * Unless required by applicable law or agreed to in writing, software 
-  * distributed under the License is distributed on an "AS IS" BASIS, 
+  * Unless required by applicable law or agreed to in writing, software
+  * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
@@ -54,36 +54,38 @@ uint8_t USB_Tx_State = 0;
 * Return         : none.
 *******************************************************************************/
 void Handle_USBAsynchXfer (void)
-{  
+{
   if(USB_Tx_State != 1)
   {
     unsigned char USB_TX_Buffer[VIRTUAL_COM_PORT_DATA_SIZE];
     int USB_Tx_length = 0;
 
     // try and fill the buffer
     int c;
-    while (USB_Tx_length<VIRTUAL_COM_PORT_DATA_SIZE && 
+    while (USB_Tx_length<VIRTUAL_COM_PORT_DATA_SIZE &&
            ((c = jshGetCharToTransmit(EV_USBSERIAL)) >=0) ) { // get byte to transmit
       USB_TX_Buffer[USB_Tx_length++] = c;
     }
 
+    jshClearUSBIdleTimeout(); // flag that USB is ready to receive data, so we can keep it in our buffer (otherwise chuck it)
+
     // if nothing, set state to 0
     if (USB_Tx_length==0) {
-      USB_Tx_State = 0; 
+      USB_Tx_State = 0;
       return;
     }
 
-    USB_Tx_State = 1; 
-    
+    USB_Tx_State = 1;
+
 #ifdef USE_STM3210C_EVAL
-    USB_SIL_Write(EP1_IN, &USB_TX_Buffer[0], USB_Tx_length);  
+    USB_SIL_Write(EP1_IN, &USB_TX_Buffer[0], USB_Tx_length);
 #else
     UserToPMABufferCopy(&USB_TX_Buffer[0], ENDP1_TXADDR, USB_Tx_length);
     SetEPTxCount(ENDP1, USB_Tx_length);
-    SetEPTxValid(ENDP1); 
+    SetEPTxValid(ENDP1);
 #endif /* USE_STM3210C_EVAL */
-  }  
-  
+  }
+
 }
 
 /*******************************************************************************
@@ -95,30 +97,31 @@ void Handle_USBAsynchXfer (void)
 *******************************************************************************/
 void EP1_IN_Callback (void)
 {
-  if (USB_Tx_State == 1)
-  {
+  if (USB_Tx_State == 1) {
     unsigned char USB_TX_Buffer[VIRTUAL_COM_PORT_DATA_SIZE];
     int USB_Tx_length = 0;
 
     // try and fill the buffer
     int c;
-    while (USB_Tx_length<VIRTUAL_COM_PORT_DATA_SIZE && 
+    while (USB_Tx_length<VIRTUAL_COM_PORT_DATA_SIZE &&
            ((c = jshGetCharToTransmit(EV_USBSERIAL)) >= 0) ) { // get byte to transmit
       USB_TX_Buffer[USB_Tx_length++] = c;
     }
-
+
+    jshClearUSBIdleTimeout(); // flag that USB is ready to receive data, so we can keep it in our buffer (otherwise chuck it)
+
     // if nothing, set state to 0
     if (USB_Tx_length==0) {
-      USB_Tx_State = 0; 
+      USB_Tx_State = 0;
       return;
-      }
-
-    // else send data and keep going      
-      UserToPMABufferCopy(&USB_TX_Buffer[0], ENDP1_TXADDR, USB_Tx_length);
-      SetEPTxCount(ENDP1, USB_Tx_length);
-      SetEPTxValid(ENDP1); 
     }
+
+    // else send data and keep going
+    UserToPMABufferCopy(&USB_TX_Buffer[0], ENDP1_TXADDR, USB_Tx_length);
+    SetEPTxCount(ENDP1, USB_Tx_length);
+    SetEPTxValid(ENDP1);
   }
+}
 
 /*******************************************************************************
 * Function Name  : EP3_OUT_Callback
@@ -131,15 +134,15 @@ void EP3_OUT_Callback(void)
 {
   uint8_t USB_Rx_Buffer[VIRTUAL_COM_PORT_DATA_SIZE];
   int USB_Rx_Cnt;
-  
+
   /* Get the received data buffer and update the counter */
   USB_Rx_Cnt = USB_SIL_Read(EP3_OUT, USB_Rx_Buffer);
-  
-  /* USB data will be immediately processed, this allow next USB traffic being 
+
+  /* USB data will be immediately processed, this allow next USB traffic being
   NAKed till the end of the USART Xfer */
-  
+
   jshPushIOCharEvents(EV_USBSERIAL, USB_Rx_Buffer, USB_Rx_Cnt);
- 
+
   /* Enable the receive of data on EP3 */
   SetEPRxStatus(ENDP3, jshHasEventSpaceForChars(VIRTUAL_COM_PORT_DATA_SIZE) ? EP_RX_VALID : EP_RX_NAK);
 }
@@ -155,21 +158,21 @@ void EP3_OUT_Callback(void)
 void SOF_Callback(void)
 {
   static uint32_t FrameCount = 0;
-  
+
   if(bDeviceState == CONFIGURED)
   {
     SetEPRxStatus(ENDP3, jshHasEventSpaceForChars(VIRTUAL_COM_PORT_DATA_SIZE) ? EP_RX_VALID : EP_RX_NAK);
-   
+
 
     if (FrameCount++ == VCOMPORT_IN_FRAME_INTERVAL)
     {
       /* Reset the frame counter */
       FrameCount = 0;
-      
+
       /* Check the data to be sent through IN pipe */
       Handle_USBAsynchXfer();
     }
-  }  
+  }
 }
 /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/