1) remove wrong global variable usage because it will bring data corrupt if there are multiple XHCI host controllers.

2) coding style clean up.

Signed-off-by: erictian
Reviewed-by: ydong10
Reviewed-by: jshi19

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12351 6f19259b-4bc3-4df7-8a09-765794883524

MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.c

@@ -45,8 +45,6 @@ EFI_DRIVER_BINDING_PROTOCOL mUsbBusDriverBinding = {
   NULL
 };
 
-UINT16 mMaxUsbDeviceNum = USB_MAX_DEVICES;
-
 /**
   USB_IO function to execute a control transfer. This
   function will execute the USB transfer. If transfer
@@ -112,7 +110,7 @@ UsbIoControlTransfer (
     // Clear TT buffer when CTRL/BULK split transaction failes
     // Clear the TRANSLATOR TT buffer, not parent's buffer
     //
-    ASSERT (Dev->Translator.TranslatorHubAddress < mMaxUsbDeviceNum);
+    ASSERT (Dev->Translator.TranslatorHubAddress < Dev->Bus->MaxDevices);
     if (Dev->Translator.TranslatorHubAddress != 0) {
       UsbHubCtrlClearTTBuffer (
         Dev->Bus->Devices[Dev->Translator.TranslatorHubAddress],
@@ -285,7 +283,7 @@ UsbIoBulkTransfer (
     // Clear TT buffer when CTRL/BULK split transaction failes.
     // Clear the TRANSLATOR TT buffer, not parent's buffer
     //
-    ASSERT (Dev->Translator.TranslatorHubAddress < mMaxUsbDeviceNum);
+    ASSERT (Dev->Translator.TranslatorHubAddress < Dev->Bus->MaxDevices);
     if (Dev->Translator.TranslatorHubAddress != 0) {
       UsbHubCtrlClearTTBuffer (
         Dev->Bus->Devices[Dev->Translator.TranslatorHubAddress],
@@ -913,8 +911,9 @@ UsbBusBuildProtocol (
     return EFI_OUT_OF_RESOURCES;
   }
 
-  UsbBus->Signature   = USB_BUS_SIGNATURE;
-  UsbBus->HostHandle  = Controller;
+  UsbBus->Signature  = USB_BUS_SIGNATURE;
+  UsbBus->HostHandle = Controller;
+  UsbBus->MaxDevices = USB_MAX_DEVICES;
 
   Status = gBS->OpenProtocol (
                   Controller,
@@ -966,12 +965,12 @@ UsbBusBuildProtocol (
   }
 
   if (!EFI_ERROR (Status)) {
+    //
+    // The EFI_USB2_HC_PROTOCOL is produced for XHCI support.
+    // Then its max supported devices are 256. Otherwise it's 128.
+    //
     if (UsbBus->Usb2Hc->MajorRevision == 0x3) {
-      //
-      // The EFI_USB2_HC_PROTOCOL is produced for XHCI support.
-      // Then its max supported devices are 256.
-      //
-      mMaxUsbDeviceNum = 256;
+      UsbBus->MaxDevices = 256;
     }
   }
 
@@ -1444,7 +1443,8 @@ UsbBusControllerDriverStop (
 
   mUsbRootHubApi.Release (RootIf);
 
-  for (Index = 1; Index < mMaxUsbDeviceNum; Index++) {
+  ASSERT (Bus->MaxDevices <= 256);
+  for (Index = 1; Index < Bus->MaxDevices; Index++) {
     if (Bus->Devices[Index] != NULL) {
       UsbRemoveDevice (Bus->Devices[Index]);
     }

MdeModulePkg/Bus/Usb/UsbBusDxe/UsbBus.h

@@ -246,6 +246,12 @@ struct _USB_BUS {
   EFI_USB2_HC_PROTOCOL      *Usb2Hc;
   EFI_USB_HC_PROTOCOL       *UsbHc;
 
+  //
+  // Recorded the max supported usb devices.
+  // XHCI can support up to 255 devices.
+  // EHCI/UHCI/OHCI supports up to 127 devices.
+  //
+  UINT32                    MaxDevices;
   //
   // An array of device that is on the bus. Devices[0] is
   // for root hub. Device with address i is at Devices[i].
@@ -747,7 +753,6 @@ UsbBusControllerDriverStop (
   IN EFI_HANDLE                   *ChildHandleBuffer
   );
 
-extern UINT16                         mMaxUsbDeviceNum;
 extern EFI_USB_IO_PROTOCOL            mUsbIoProtocol;
 extern EFI_DRIVER_BINDING_PROTOCOL    mUsbBusDriverBinding;
 extern EFI_COMPONENT_NAME_PROTOCOL    mUsbBusComponentName;

MdeModulePkg/Bus/Usb/UsbBusDxe/UsbEnumer.c

@@ -548,7 +548,7 @@ UsbRemoveDevice (
   // Remove all the devices on its downstream ports. Search from devices[1].
   // Devices[0] is the root hub.
   //
-  for (Index = 1; Index < mMaxUsbDeviceNum; Index++) {
+  for (Index = 1; Index < Bus->MaxDevices; Index++) {
     Child = Bus->Devices[Index];
 
     if ((Child == NULL) || (Child->ParentAddr != Device->Address)) {
@@ -567,7 +567,7 @@ UsbRemoveDevice (
 
   DEBUG (( EFI_D_INFO, "UsbRemoveDevice: device %d removed\n", Device->Address));
 
-  ASSERT (Device->Address < mMaxUsbDeviceNum);
+  ASSERT (Device->Address < Bus->MaxDevices);
   Bus->Devices[Device->Address] = NULL;
   UsbFreeDevice (Device);
 
@@ -599,7 +599,7 @@ UsbFindChild (
   //
   // Start checking from device 1, device 0 is the root hub
   //
-  for (Index = 1; Index < mMaxUsbDeviceNum; Index++) {
+  for (Index = 1; Index < Bus->MaxDevices; Index++) {
     Device = Bus->Devices[Index];
 
     if ((Device != NULL) && (Device->ParentAddr == HubIf->Device->Address) &&
@@ -639,11 +639,11 @@ UsbEnumerateNewDev (
   UINT8                   Config;
   EFI_STATUS              Status;
 
-  Address = mMaxUsbDeviceNum;
   Parent  = HubIf->Device;
   Bus     = Parent->Bus;
-  HubApi  = HubIf->HubApi;
-  
+  HubApi  = HubIf->HubApi;  
+  Address = Bus->MaxDevices;
+
   gBS->Stall (USB_WAIT_PORT_STABLE_STALL);
   
   //
@@ -731,13 +731,14 @@ UsbEnumerateNewDev (
   // status stage with default address, then switches to new address.
   // ADDRESS state. Address zero is reserved for root hub.
   //
-  for (Address = 1; Address < mMaxUsbDeviceNum; Address++) {
+  ASSERT (Bus->MaxDevices <= 256);
+  for (Address = 1; Address < Bus->MaxDevices; Address++) {
     if (Bus->Devices[Address] == NULL) {
       break;
     }
   }
 
-  if (Address == mMaxUsbDeviceNum) {
+  if (Address >= Bus->MaxDevices) {
     DEBUG ((EFI_D_ERROR, "UsbEnumerateNewDev: address pool is full for port %d\n", Port));
 
     Status = EFI_ACCESS_DENIED;
@@ -808,7 +809,7 @@ UsbEnumerateNewDev (
   return EFI_SUCCESS;
 
 ON_ERROR:
-  if (Address != mMaxUsbDeviceNum) {
+  if (Address != Bus->MaxDevices) {
     Bus->Devices[Address] = NULL;
   }