X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/922e60192dc089654a82be0d789fb7a8ecc47039..7aecda6fda5bcced68d72b0cf73d00174aa5c7cd:/Demos/Host/LowLevel/MassStorageHost/Lib/MassStoreCommands.c

diff --git a/Demos/Host/LowLevel/MassStorageHost/Lib/MassStoreCommands.c b/Demos/Host/LowLevel/MassStorageHost/Lib/MassStoreCommands.c
index 1deefbcb6..edd142525 100644
--- a/Demos/Host/LowLevel/MassStorageHost/Lib/MassStoreCommands.c
+++ b/Demos/Host/LowLevel/MassStorageHost/Lib/MassStoreCommands.c
@@ -50,7 +50,6 @@
 #define  INCLUDE_FROM_MASSSTORE_COMMANDS_C
 #include "MassStoreCommands.h"
 
-/* Globals: */
 /** Current Tag value used in issued CBWs to the device. This is automatically incremented
  *  each time a command is sent, and is not externally accessible.
  */
@@ -238,7 +237,7 @@ static uint8_t MassStore_GetReturnedStatus(CommandStatusWrapper_t* SCSICommandSt
 {
 	uint8_t ErrorCode = PIPE_RWSTREAM_NoError;
 
-	/* If an error in the command ocurred, abort */
+	/* If an error in the command occurred, abort */
 	if ((ErrorCode = MassStore_WaitForDataReceived()) != PIPE_RWSTREAM_NoError)
 	  return ErrorCode;
 
@@ -288,13 +287,17 @@ uint8_t MassStore_MassStorageReset(void)
 /** Issues a Mass Storage class specific request to determine the index of the highest numbered Logical
  *  Unit in the attached device.
  *
+ *  \note Some devices do not support this request, and will STALL it when issued. To get around this,
+ *        on unsupported devices the max LUN index will be reported as zero and no error will be returned
+ *        if the device STALLs the request.
+ *
  *  \param[out] MaxLUNIndex  Pointer to the location that the maximum LUN index value should be stored
  *
  *  \return A value from the USB_Host_SendControlErrorCodes_t enum, or MASS_STORE_SCSI_COMMAND_FAILED if the SCSI command fails
  */
 uint8_t MassStore_GetMaxLUN(uint8_t* const MaxLUNIndex)
 {
-	uint8_t ErrorCode;
+	uint8_t ErrorCode = HOST_SENDCONTROL_Successful;
 
 	USB_ControlRequest = (USB_Request_Header_t)
 		{
@@ -314,7 +317,10 @@ uint8_t MassStore_GetMaxLUN(uint8_t* const MaxLUNIndex)
 		Pipe_ClearStall();
 	
 		/* Some faulty Mass Storage devices don't implement the GET_MAX_LUN request, so assume a single LUN */
-		*MaxLUNIndex = 0;	
+		*MaxLUNIndex = 0;
+		
+		/* Clear the error, and pretend the request executed correctly if the device STALLed it */
+		ErrorCode = HOST_SENDCONTROL_Successful;
 	}
 	
 	return ErrorCode;