From 6c5ad5e23958d10db801e61b59aeee9ec9374e8a Mon Sep 17 00:00:00 2001
From: Cameron Gutman <aicommander@gmail.com>
Date: Wed, 1 Feb 2012 11:22:43 +0000
Subject: [PATCH] [USBEHCI] - Wait 20 milliseconds after enabling power for the
 port to stabilize

svn path=/branches/usb-bringup-trunk/; revision=55365
---
 drivers/usb/usbehci_new/hardware.cpp | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/usbehci_new/hardware.cpp b/drivers/usb/usbehci_new/hardware.cpp
index 672a228d822..0ba69d66f21 100644
--- a/drivers/usb/usbehci_new/hardware.cpp
+++ b/drivers/usb/usbehci_new/hardware.cpp
@@ -957,11 +957,30 @@ CUSBHardwareDevice::SetPortFeature(
     {
         if (m_Capabilities.HCSParams.PortPowerControl)
         {
+            ULONG Value;
+            LARGE_INTEGER Timeout;
+
             //
             // enable port power
             //
-            ULONG Value = EHCI_READ_REGISTER_ULONG(EHCI_PORTSC + (4 * PortId)) | EHCI_PRT_POWER;
+            Value = EHCI_READ_REGISTER_ULONG(EHCI_PORTSC + (4 * PortId)) | EHCI_PRT_POWER;
             EHCI_WRITE_REGISTER_ULONG(EHCI_PORTSC, Value);
+
+            //
+            // delay is 20 ms
+            //
+            Timeout.QuadPart = 20;
+            DPRINT1("Waiting %d milliseconds for port power up\n", Timeout.LowPart);
+
+            //
+            // convert to 100 ns units (absolute)
+            //
+            Timeout.QuadPart *= -10000;
+
+            //
+            // perform the wait
+            //
+            KeDelayExecutionThread(KernelMode, FALSE, &Timeout);
         }
     }
     return STATUS_SUCCESS;