EmbeddedPkg/SerialDxe: Do not block UART when no data is available on the port

Signed-off-by: Olivier Martin <olivier.martin@arm.com>



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13255 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 7 insertions, 6 deletions

diff --git a/EmbeddedPkg/SerialDxe/SerialIo.c b/EmbeddedPkg/SerialDxe/SerialIo.c
index 59d904c192..ef4e6a1910 100644
--- a/EmbeddedPkg/SerialDxe/SerialIo.c
+++ b/EmbeddedPkg/SerialDxe/SerialIo.c
@@ -167,7 +167,7 @@ SerialWrite (
 }

 

 /**

-  Writes data to a serial device.

+  Reads data from a serial device.

 

   @param  This              Protocol instance pointer.

   @param  BufferSize        On input, the size of the Buffer. On output, the amount of

@@ -189,15 +189,16 @@ SerialRead (
   )

 {

   UINTN Count = 0;

-  

+

   if (SerialPortPoll()) {

     Count = SerialPortRead (Buffer, *BufferSize);

+  }

+

+  if (Count != *BufferSize) {

     *BufferSize = Count;

-    return (Count == 0) ? EFI_DEVICE_ERROR : EFI_SUCCESS;

+    return EFI_TIMEOUT;

   }

-  

-  // No data to return

-  *BufferSize = 0;

+

   return EFI_SUCCESS;

 }