Fixed bug #930.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/trunk@11855 110e8d01-0319-4d1e-a829-52ad28d1bb01

1 files changed, 11 insertions, 6 deletions

diff --git a/os/hal/src/hal_serial_usb.c b/os/hal/src/hal_serial_usb.c
index ec1f1c4fe..246360ebc 100644
--- a/os/hal/src/hal_serial_usb.c
+++ b/os/hal/src/hal_serial_usb.c
@@ -484,20 +484,25 @@ void sduDataTransmitted(USBDriver *usbp, usbep_t ep) {
  * @param[in] ep        OUT endpoint number

  */

 void sduDataReceived(USBDriver *usbp, usbep_t ep) {

+  size_t size;

   SerialUSBDriver *sdup = usbp->out_params[ep - 1U];

+

   if (sdup == NULL) {

     return;

   }

 

   osalSysLockFromISR();

 

-  /* Signaling that data is available in the input queue.*/

-  chnAddFlagsI(sdup, CHN_INPUT_AVAILABLE);

+  /* Checking for zero-size transactions.*/

+  size = usbGetReceiveTransactionSizeX(sdup->config->usbp,

+                                       sdup->config->bulk_out);

+  if (size > (size_t)0) {

+    /* Signaling that data is available in the input queue.*/

+    chnAddFlagsI(sdup, CHN_INPUT_AVAILABLE);

 

-  /* Posting the filled buffer in the queue.*/

-  ibqPostFullBufferI(&sdup->ibqueue,

-                     usbGetReceiveTransactionSizeX(sdup->config->usbp,

-                                                   sdup->config->bulk_out));

+    /* Posting the filled buffer in the queue.*/

+    ibqPostFullBufferI(&sdup->ibqueue, size);

+  }

 

   /* The endpoint cannot be busy, we are in the context of the callback,

      so a packet is in the buffer for sure. Trying to get a free buffer