From: Serge Gautherie <reactos-git_serge_fake@gautherie.fr>
Date: Fri, 24 Mar 2017 07:25:00 +0100
Subject: [I8042PRT]
pnp.c: Better manage 'HighestDIRQLInterrupt', and more...
(Improved from Trivalik's and hater's ideas.)
CORE-12960


Index: reactos/drivers/input/i8042prt/pnp.c
--- a/reactos/drivers/input/i8042prt/pnp.c
+++ b/reactos/drivers/input/i8042prt/pnp.c
@@ -303,7 +303,9 @@
         return Status;
     }
 
-    if (DirqlMax == PortDeviceExtension->KeyboardInterrupt.Dirql)
+/* Or do we want to revert to pre-r30000:
+   unconditional "PortDeviceExtension->HighestDIRQLInterrupt = DirqlMax;"? */
+    if (PortDeviceExtension->KeyboardInterrupt.Dirql > PortDeviceExtension->HighestDIRQLInterrupt)
         PortDeviceExtension->HighestDIRQLInterrupt = PortDeviceExtension->KeyboardInterrupt.Object;
     PortDeviceExtension->Flags |= KEYBOARD_INITIALIZED;
     return STATUS_SUCCESS;
@@ -350,15 +352,19 @@
     if (!NT_SUCCESS(Status))
     {
         WARN_(I8042PRT, "IoConnectInterrupt() failed with status 0x%08x\n", Status);
-        goto cleanup;
+        return Status; // goto cleanup;
     }
 
-    if (DirqlMax == PortDeviceExtension->MouseInterrupt.Dirql)
+/* Or do we want to revert to pre-r30000:
+   unconditional "PortDeviceExtension->HighestDIRQLInterrupt = DirqlMax;"? */
+    if (PortDeviceExtension->MouseInterrupt.Dirql > PortDeviceExtension->HighestDIRQLInterrupt)
         PortDeviceExtension->HighestDIRQLInterrupt = PortDeviceExtension->MouseInterrupt.Object;
-
     PortDeviceExtension->Flags |= MOUSE_INITIALIZED;
-    Status = STATUS_SUCCESS;
+    // Status = STATUS_SUCCESS;
 
+#if 0
+/* Added by r30000. But useless, isn't it? */
+
 cleanup:
     if (!NT_SUCCESS(Status))
     {
@@ -366,10 +372,13 @@
         if (PortDeviceExtension->MouseInterrupt.Object)
         {
             IoDisconnectInterrupt(PortDeviceExtension->MouseInterrupt.Object);
+/* This is even incorrect. */
             PortDeviceExtension->HighestDIRQLInterrupt = PortDeviceExtension->KeyboardInterrupt.Object;
         }
     }
-    return Status;
+#endif
+
+    return STATUS_SUCCESS; // return Status;
 }
 
 static NTSTATUS
@@ -386,6 +395,7 @@
     return STATUS_SUCCESS;
 }
 
+/* Nit: Would you accept s/DeviceExtension/PortDeviceExtension/g so we use same name everywhere (all files)? */
 static NTSTATUS
 StartProcedure(
     IN PPORT_DEVICE_EXTENSION DeviceExtension)
@@ -443,6 +453,9 @@
         }
     }
 
+// I assume this ASSERT would be true, hence unneeded, isn't it?
+    ASSERT(DeviceExtension->HighestDIRQLInterrupt == 0);
+
     /* Connect interrupts */
     if (DeviceExtension->Flags & KEYBOARD_PRESENT &&
         DeviceExtension->Flags & KEYBOARD_CONNECTED &&
@@ -471,22 +484,29 @@
         if (NT_SUCCESS(Status))
         {
             DeviceExtension->Flags |= MOUSE_INITIALIZED;
+
+/* Or do we actually want to reset even when uninitialized? (See r53911 and older.)
+   Then, instead of moving code here,
+   the 2 SpinLock lines would need "if (DeviceExtension->HighestDIRQLInterrupt)" and/or MOUSE_INITIALIZED... */
+            /* HACK: the mouse has already been reset in i8042DetectMouse. This second
+               reset prevents some touchpads/mice from working (Dell D531, D600).
+               See CORE-6901 */
+            if (!(i8042HwFlags & FL_INITHACK))
+            {
+                /* Start the mouse */
+                Irql = KeAcquireInterruptSpinLock(DeviceExtension->HighestDIRQLInterrupt);
+                i8042IsrWritePort(DeviceExtension, MOU_CMD_RESET, CTRL_WRITE_MOUSE);
+                KeReleaseInterruptSpinLock(DeviceExtension->HighestDIRQLInterrupt, Irql);
+            }
+            else
+            {
+                WARN_(I8042PRT, "Skip mouse reset, because FL_INITHACK hardware is detected.\n");
+            }
         }
         else
         {
             WARN_(I8042PRT, "i8042ConnectMouseInterrupt failed: %lx\n", Status);
         }
-
-        /* Start the mouse */
-        Irql = KeAcquireInterruptSpinLock(DeviceExtension->HighestDIRQLInterrupt);
-        /* HACK: the mouse has already been reset in i8042DetectMouse. This second
-           reset prevents some touchpads/mice from working (Dell D531, D600).
-           See CORE-6901 */
-        if (!(i8042HwFlags & FL_INITHACK))
-        {
-            i8042IsrWritePort(DeviceExtension, MOU_CMD_RESET, CTRL_WRITE_MOUSE);
-        }
-        KeReleaseInterruptSpinLock(DeviceExtension->HighestDIRQLInterrupt, Irql);
     }
 
     return Status;