From a840459c379681c5017d72a9fdd4aaa7781eb7b1 Mon Sep 17 00:00:00 2001
From: Dmitry Gorbachev <gorbachev@reactos.org>
Date: Wed, 7 Feb 2007 00:29:50 +0000
Subject: [PATCH] Fix "keyboard does not respond" bug. Thanks to Peter Krawies
 (breakoutbox /AT/ web /DOT/ de)

svn path=/trunk/; revision=25745
---
 .../boot/freeldr/freeldr/arch/i386/hardware.c | 34 +++++++++++++------
 1 file changed, 24 insertions(+), 10 deletions(-)

diff --git a/reactos/boot/freeldr/freeldr/arch/i386/hardware.c b/reactos/boot/freeldr/freeldr/arch/i386/hardware.c
index a7c8a894abb..15343b3c51b 100644
--- a/reactos/boot/freeldr/freeldr/arch/i386/hardware.c
+++ b/reactos/boot/freeldr/freeldr/arch/i386/hardware.c
@@ -1925,6 +1925,8 @@ DetectPS2AuxDevice(VOID)
 {
   UCHAR Scancode;
   UCHAR Status;
+  ULONG Loops;
+  BOOLEAN Result = TRUE;
 
   PS2ControllerWait();
   WRITE_PORT_UCHAR((PUCHAR)CONTROLLER_REGISTER_CONTROL,
@@ -1935,31 +1937,43 @@ DetectPS2AuxDevice(VOID)
   WRITE_PORT_UCHAR((PUCHAR)CONTROLLER_REGISTER_DATA,
 		   0xF2);
 
-  StallExecutionProcessor(10000);
+  /* Wait for reply */
+  for (Loops = 0; Loops < 10; Loops++)
+    {
+      StallExecutionProcessor(10000);
+      Status = READ_PORT_UCHAR((PUCHAR)CONTROLLER_REGISTER_STATUS);
+      if ((Status & CONTROLLER_STATUS_OUTPUT_BUFFER_FULL) != 0)
+        break;
+    }
 
   Status = READ_PORT_UCHAR((PUCHAR)CONTROLLER_REGISTER_STATUS);
   if ((Status & CONTROLLER_STATUS_MOUSE_OUTPUT_BUFFER_FULL) == 0)
-    {
-      return FALSE;
-    }
+    Result = FALSE;
 
   Scancode = READ_PORT_UCHAR((PUCHAR)CONTROLLER_REGISTER_DATA);
   if (Scancode != 0xFA)
-    return FALSE;
+    Result = FALSE;
 
   StallExecutionProcessor(10000);
 
   Status = READ_PORT_UCHAR((PUCHAR)CONTROLLER_REGISTER_STATUS);
   if ((Status & CONTROLLER_STATUS_MOUSE_OUTPUT_BUFFER_FULL) == 0)
-    {
-      return FALSE;
-    }
+    Result = FALSE;
 
   Scancode = READ_PORT_UCHAR((PUCHAR)CONTROLLER_REGISTER_DATA);
   if (Scancode != 0x00)
-    return FALSE;
+    Result = FALSE;
 
-  return TRUE;
+  /* Flush output buffer */
+  for (Loops = 0; Loops < 10; Loops++)
+    {
+      Status = READ_PORT_UCHAR((PUCHAR)CONTROLLER_REGISTER_STATUS);
+      if ((Status & CONTROLLER_STATUS_OUTPUT_BUFFER_FULL) == 0)
+        break;
+      StallExecutionProcessor(10000);
+    }
+
+  return Result;
 }