X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/158afe910947739b1df00000628c1e758bdf0812..accadba2dda2614d6a6669cb7eba9d8357274bfe:/Demos/Host/LowLevel/VirtualSerialHost/ConfigDescriptor.c

diff --git a/Demos/Host/LowLevel/VirtualSerialHost/ConfigDescriptor.c b/Demos/Host/LowLevel/VirtualSerialHost/ConfigDescriptor.c
index c35a606cc..7d9fb38c0 100644
--- a/Demos/Host/LowLevel/VirtualSerialHost/ConfigDescriptor.c
+++ b/Demos/Host/LowLevel/VirtualSerialHost/ConfigDescriptor.c
@@ -51,9 +51,10 @@ uint8_t ProcessConfigurationDescriptor(void)
 	void*    CurrConfigLocation = ConfigDescriptorData;
 	uint16_t CurrConfigBytesRem;
 	
-	USB_Descriptor_Endpoint_t* DataINEndpoint       = NULL;
-	USB_Descriptor_Endpoint_t* DataOUTEndpoint      = NULL;
-	USB_Descriptor_Endpoint_t* NotificationEndpoint = NULL;
+	USB_Descriptor_Interface_t* CDCControlInterface  = NULL;
+	USB_Descriptor_Endpoint_t*  DataINEndpoint       = NULL;
+	USB_Descriptor_Endpoint_t*  DataOUTEndpoint      = NULL;
+	USB_Descriptor_Endpoint_t*  NotificationEndpoint = NULL;
 
 	/* Retrieve the entire configuration descriptor into the allocated buffer */
 	switch (USB_Host_GetDeviceConfigDescriptor(1, &CurrConfigBytesRem, ConfigDescriptorData, sizeof(ConfigDescriptorData)))
@@ -67,19 +68,12 @@ uint8_t ProcessConfigurationDescriptor(void)
 		default:
 			return ControlError;
 	}
-	
-	/* Get the first CDC control interface from the configuration descriptor */
-	if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
-	                              DComp_NextCDCControlInterface) != DESCRIPTOR_SEARCH_COMP_Found)
-	{
-		/* Descriptor not found, error out */
-		return NoCompatibleInterfaceFound;
-	}
 
 	while (!(DataINEndpoint) || !(DataOUTEndpoint) || !(NotificationEndpoint))
 	{
-		/* Get the next CDC interface's endpoint descriptor */
-		if (USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
+		/* See if we've found a likely compatible interface, and if there is an endpoint within that interface */
+		if (!(CDCControlInterface) ||
+		    USB_GetNextDescriptorComp(&CurrConfigBytesRem, &CurrConfigLocation,
 		                              DComp_NextCDCDataInterfaceEndpoint) != DESCRIPTOR_SEARCH_COMP_Found)
 		{
 			/* Check if we have already found the control interface's notification endpoint or not */
@@ -107,9 +101,15 @@ uint8_t ProcessConfigurationDescriptor(void)
 					return NoCompatibleInterfaceFound;
 				}
 
+				/* Save the interface in case we need to refer back to it later */
+				CDCControlInterface = DESCRIPTOR_PCAST(CurrConfigLocation, USB_Descriptor_Interface_t);
+
 				/* Clear any found endpoints */
 				NotificationEndpoint = NULL;
 			}
+
+			/* Skip the remainder of the loop as we have not found an endpoint yet */
+			continue;
 		}
 		
 		/* Retrieve the endpoint address from the endpoint descriptor */