diff --git a/EdkModulePkg/Bus/Usb/UsbBot/Dxe/bot.c b/EdkModulePkg/Bus/Usb/UsbBot/Dxe/bot.c
index 37b316f875..fd830ec56e 100644
--- a/EdkModulePkg/Bus/Usb/UsbBot/Dxe/bot.c
+++ b/EdkModulePkg/Bus/Usb/UsbBot/Dxe/bot.c
@@ -441,8 +441,6 @@ BotDriverBindingStop (
   EFI_USB_ATAPI_PROTOCOL  *BotAtapiProtocol;
   USB_BOT_DEVICE          *UsbBotDev;
 
-  EFI_USB_IO_PROTOCOL     *UsbIo;
-
   //
   // Get our context back.
   //
@@ -464,7 +462,6 @@ BotDriverBindingStop (
   // After installing Usb-Atapi protocol onto this handle
   // it will be called by upper layer drivers such as Fat
   //
-  UsbIo = UsbBotDev->UsbIo;
 
   BotReportStatusCode (
     UsbBotDev->DevicePath,
diff --git a/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbbus.c b/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbbus.c
index 029d9cb425..ffca53595e 100644
--- a/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbbus.c
+++ b/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbbus.c
@@ -84,14 +84,6 @@ ReportUsbStatusCode (
   IN EFI_STATUS_CODE_VALUE         Code
   );
 
-//
-// Supported function
-//
-VOID
-InitializeUsbIoInstance (
-  IN USB_IO_CONTROLLER_DEVICE     *UsbIoController
-  );
-
 STATIC
 USB_IO_CONTROLLER_DEVICE    *
 CreateUsbIoControllerDevice (
@@ -213,7 +205,7 @@ UsbAllocateAddress (
         //
         // Found one, covert to address, and mark it use
         //
-        AddressPool[ByteIndex] |= (1 << BitIndex);
+        AddressPool[ByteIndex] = (UINT8) (AddressPool[ByteIndex] | (1 << BitIndex));
         return (UINT8) (ByteIndex * 8 + BitIndex);
       }
     }
@@ -251,7 +243,7 @@ UsbFreeAddress (
   WhichByte = (UINT8) (DevAddress / 8);
   WhichBit  = (UINT8) (DevAddress & 0x7);
 
-  AddressPool[WhichByte] &= (~(1 << WhichBit));
+  AddressPool[WhichByte] = (UINT8) (AddressPool[WhichByte] & (~(1 << WhichBit)));
 }
 
 EFI_STATUS
@@ -2277,7 +2269,7 @@ ParentPortReset (
     ResetRootPort (ParentIoDev->BusController, HubPort, RetryTimes);
   } else {
     DEBUG ((gUSBDebugLevel, "Reset from Hub, Addr 0x%x\n", ParentIoDev->DeviceAddress));
-    ResetHubPort (ParentController, HubPort + 1);
+    ResetHubPort (ParentController, (UINT8) (HubPort + 1));
   }
   //
   // If we only need port reset, just return
@@ -2580,16 +2572,13 @@ IsDeviceDisconnected (
 --*/
 {
   USB_IO_DEVICE             *ParentIoDev;
-  USB_IO_DEVICE             *UsbIoDev;
   USB_IO_CONTROLLER_DEVICE  *ParentController;
   UINT8                     HubPort;
   EFI_STATUS                Status;
-  EFI_USB_IO_PROTOCOL       *UsbIo;
   EFI_USB_PORT_STATUS       PortStatus;
 
   ParentController  = UsbIoController->Parent;
   ParentIoDev       = ParentController->UsbDevice;
-  UsbIoDev          = UsbIoController->UsbDevice;
   HubPort           = UsbIoController->ParentPort;
 
   if (ParentIoDev->DeviceAddress == 1) {
@@ -2603,10 +2592,9 @@ IsDeviceDisconnected (
       );
 
   } else {
-    UsbIo = &UsbIoController->UsbIo;
     Status = HubGetPortStatus (
               &ParentController->UsbIo,
-              HubPort + 1,
+              (UINT8) (HubPort + 1),
               (UINT32 *) &PortStatus
               );
 
@@ -3308,7 +3296,7 @@ UsbVirtualHcControlTransfer (
                                           TransferResult
                                           );
   } else {
-    IsSlowDevice = (EFI_USB_SPEED_LOW == DeviceSpeed) ? TRUE : FALSE;
+    IsSlowDevice = (BOOLEAN) ((EFI_USB_SPEED_LOW == DeviceSpeed) ? TRUE : FALSE);
     Status = UsbBusDev->UsbHCInterface->ControlTransfer (
                                           UsbBusDev->UsbHCInterface,
                                           DeviceAddress,
@@ -3530,7 +3518,7 @@ UsbVirtualHcAsyncInterruptTransfer (
                                           Context
                                           );
   } else {
-    IsSlowDevice = (EFI_USB_SPEED_LOW == DeviceSpeed) ? TRUE : FALSE;
+    IsSlowDevice = (BOOLEAN) ((EFI_USB_SPEED_LOW == DeviceSpeed) ? TRUE : FALSE);
     Status = UsbBusDev->UsbHCInterface->AsyncInterruptTransfer (
                                           UsbBusDev->UsbHCInterface,
                                           DeviceAddress,
@@ -3639,7 +3627,7 @@ UsbVirtualHcSyncInterruptTransfer (
                                           TransferResult
                                           );
   } else {
-    IsSlowDevice = (EFI_USB_SPEED_LOW == DeviceSpeed) ? TRUE : FALSE;
+    IsSlowDevice = (BOOLEAN) ((EFI_USB_SPEED_LOW == DeviceSpeed) ? TRUE : FALSE);
     Status = UsbBusDev->UsbHCInterface->SyncInterruptTransfer (
                                           UsbBusDev->UsbHCInterface,
                                           DeviceAddress,
diff --git a/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbbus.h b/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbbus.h
index a5d4c2426c..4977d71695 100644
--- a/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbbus.h
+++ b/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbbus.h
@@ -1111,4 +1111,45 @@ UsbVirtualHcAsyncIsochronousTransfer (
 --*/
 ;
 
+EFI_STATUS
+EFIAPI
+UsbPortReset (
+  IN EFI_USB_IO_PROTOCOL     *This
+  )
+/*++
+
+  Routine Description:
+    Resets and reconfigures the USB controller.  This function will
+    work for all USB devices except USB Hub Controllers.
+
+  Arguments:
+    This          -   Indicates the calling context.
+
+  Returns:
+    EFI_SUCCESS
+    EFI_INVALID_PARAMETER
+    EFI_DEVICE_ERROR
+
+--*/
+;
+
+VOID
+InitializeUsbIoInstance (
+  IN USB_IO_CONTROLLER_DEVICE     *UsbIoController
+  )
+/*++
+
+Routine Description:
+
+  Initialize the instance of UsbIo controller
+
+Arguments:
+
+  UsbIoController - A pointer to controller structure of UsbIo
+
+Returns:
+
+--*/
+;
+
 #endif
diff --git a/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbio.c b/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbio.c
index afd2e46541..4601767f64 100644
--- a/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbio.c
+++ b/EdkModulePkg/Bus/Usb/UsbBus/Dxe/usbio.c
@@ -99,13 +99,6 @@ UsbAsyncIsochronousTransfer (
   IN        VOID                                *Context OPTIONAL
   );
 
-extern
-EFI_STATUS
-EFIAPI
-UsbPortReset (
-  IN EFI_USB_IO_PROTOCOL     *This
-  );
-
 STATIC
 EFI_STATUS
 EFIAPI
diff --git a/EdkModulePkg/Bus/Usb/UsbMassStorage/Dxe/UsbMassStorageHelper.c b/EdkModulePkg/Bus/Usb/UsbMassStorage/Dxe/UsbMassStorageHelper.c
index c81fbf299e..c011349a78 100644
--- a/EdkModulePkg/Bus/Usb/UsbMassStorage/Dxe/UsbMassStorageHelper.c
+++ b/EdkModulePkg/Bus/Usb/UsbMassStorage/Dxe/UsbMassStorageHelper.c
@@ -234,9 +234,7 @@ USBFloppyInquiry (
 {
   ATAPI_PACKET_COMMAND    Packet;
   EFI_STATUS              Status;
-  EFI_USB_ATAPI_PROTOCOL  *UsbAtapiInterface;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   //
   // prepare command packet for the Inquiry Packet Command.
@@ -309,10 +307,8 @@ USBFloppyRead10 (
   VOID                    *ptrBuffer;
   EFI_STATUS              Status;
   UINT16                  TimeOut;
-  EFI_USB_ATAPI_PROTOCOL  *UsbAtapiInterface;
   UINT8                   Index;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   //
   // prepare command packet for the Inquiry Packet Command.
@@ -387,6 +383,7 @@ USBFloppyRead10 (
   return Status;
 }
 
+STATIC
 EFI_STATUS
 USBFloppyReadCapacity (
   IN  USB_FLOPPY_DEV    *UsbFloppyDevice
@@ -410,7 +407,6 @@ USBFloppyReadCapacity (
   //
   EFI_STATUS              Status;
   ATAPI_PACKET_COMMAND    Packet;
-  EFI_USB_ATAPI_PROTOCOL  *UsbAtapiInterface;
 
   //
   // used for capacity data returned from Usb Floppy
@@ -419,7 +415,6 @@ USBFloppyReadCapacity (
 
   ZeroMem (&Data, sizeof (Data));
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   ZeroMem (&Packet, sizeof (ATAPI_PACKET_COMMAND));
   Packet.Inquiry.opcode = READ_CAPACITY;
@@ -473,7 +468,6 @@ USBFloppyReadFormatCapacity (
   //
   EFI_STATUS                Status;
   ATAPI_PACKET_COMMAND      Packet;
-  EFI_USB_ATAPI_PROTOCOL    *UsbAtapiInterface;
 
   //
   // used for capacity data returned from Usb Floppy
@@ -482,7 +476,6 @@ USBFloppyReadFormatCapacity (
 
   ZeroMem (&FormatData, sizeof (FormatData));
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   ZeroMem (&Packet, sizeof (ATAPI_PACKET_COMMAND));
   Packet.ReadFormatCapacity.opcode                = READ_FORMAT_CAPACITY;
@@ -556,9 +549,7 @@ UsbFloppyRequestSense (
   UINT8                   *Ptr;
   BOOLEAN                 SenseReq;
   ATAPI_PACKET_COMMAND    Packet;
-  EFI_USB_ATAPI_PROTOCOL  *UsbAtapiInterface;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   *SenseCounts      = 0;
 
@@ -672,11 +663,9 @@ UsbFloppyTestUnitReady (
 {
   ATAPI_PACKET_COMMAND      Packet;
   EFI_STATUS                Status;
-  EFI_USB_ATAPI_PROTOCOL    *UsbAtapiInterface;
   UINT32                    RetryIndex;
   UINT32                    MaximumRetryTimes;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
   MaximumRetryTimes = 2;
   //
   // fill command packet
@@ -748,10 +737,8 @@ USBFloppyWrite10 (
   VOID                    *ptrBuffer;
   EFI_STATUS              Status;
   UINT16                  TimeOut;
-  EFI_USB_ATAPI_PROTOCOL  *UsbAtapiInterface;
   UINT8                   Index;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   //
   // prepare command packet for the Write10 Packet Command.
@@ -863,8 +850,6 @@ UsbFloppyDetectMedia (
   // a flag used to determine whether need to perform Read Capacity command.
   //
 
-  REQUEST_SENSE_DATA  *SensePtr;
-
   //
   // init
   //
@@ -884,8 +869,6 @@ UsbFloppyDetectMedia (
 
   if (!EFI_ERROR (Status)) {
 
-    SensePtr = UsbFloppyDevice->SenseData;
-
     //
     // No Media
     //
@@ -1124,7 +1107,6 @@ UsbFloppyModeSense5APage5 (
   //
   EFI_STATUS                Status;
   ATAPI_PACKET_COMMAND      Packet;
-  EFI_USB_ATAPI_PROTOCOL    *UsbAtapiInterface;
   UFI_MODE_PARAMETER_PAGE_5 ModePage5;
   EFI_LBA                   LastBlock;
   UINT32                    SectorsPerTrack;
@@ -1132,7 +1114,6 @@ UsbFloppyModeSense5APage5 (
   UINT32                    NumberOfHeads;
   UINT32                    DataBytesPerSector;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   ZeroMem (&ModePage5, sizeof (UFI_MODE_PARAMETER_PAGE_5));
 
@@ -1210,10 +1191,8 @@ UsbFloppyModeSense5APage1C (
   //
   EFI_STATUS                  Status;
   ATAPI_PACKET_COMMAND        Packet;
-  EFI_USB_ATAPI_PROTOCOL      *UsbAtapiInterface;
   UFI_MODE_PARAMETER_PAGE_1C  ModePage1C;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   ZeroMem (&ModePage1C, sizeof (UFI_MODE_PARAMETER_PAGE_1C));
 
@@ -1285,11 +1264,9 @@ UsbFloppyModeSense5APage3F (
   //
   EFI_STATUS                Status;
   ATAPI_PACKET_COMMAND      Packet;
-  EFI_USB_ATAPI_PROTOCOL    *UsbAtapiInterface;
   UFI_MODE_PARAMETER_HEADER Header;
   UINT32                    Size;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   Size              = sizeof (UFI_MODE_PARAMETER_HEADER);
 
@@ -1343,11 +1320,9 @@ UsbSCSIModeSense1APage3F (
   //
   EFI_STATUS                  Status;
   ATAPI_PACKET_COMMAND        Packet;
-  EFI_USB_ATAPI_PROTOCOL      *UsbAtapiInterface;
   SCSI_MODE_PARAMETER_HEADER6 Header;
   UINT32                      Size;
 
-  UsbAtapiInterface = UsbFloppyDevice->AtapiProtocol;
 
   Size              = sizeof (SCSI_MODE_PARAMETER_HEADER6);
 
diff --git a/EdkModulePkg/Library/EdkGraphicsLib/Graphics.c b/EdkModulePkg/Library/EdkGraphicsLib/Graphics.c
index 69b1a2b18e..00e556ea21 100644
--- a/EdkModulePkg/Library/EdkGraphicsLib/Graphics.c
+++ b/EdkModulePkg/Library/EdkGraphicsLib/Graphics.c
@@ -22,15 +22,6 @@ Abstract:
 
 --*/
 
-EFI_STATUS
-ConvertBmpToGopBlt (
-  IN  VOID      *BmpImage,
-  IN  UINTN     BmpImageSize,
-  IN OUT VOID   **GopBlt,
-  IN OUT UINTN  *GopBltSize,
-  OUT UINTN     *PixelHeight,
-  OUT UINTN     *PixelWidth
-  );
 
 EFI_STATUS
 GetGraphicsBitMapFromFV (
@@ -115,6 +106,7 @@ Returns:
   return EFI_NOT_FOUND;
 }
 
+STATIC
 EFI_STATUS
 ConvertBmpToGopBlt (
   IN  VOID      *BmpImage,
@@ -450,6 +442,7 @@ Returns:
     }
 
     Blt = NULL;
+    BltSize = 0;
     Status = ConvertBmpToGopBlt (
               ImageData,
               ImageSize,
diff --git a/EdkModulePkg/Universal/Ebc/Dxe/Ipf/EbcSupport.c b/EdkModulePkg/Universal/Ebc/Dxe/Ipf/EbcSupport.c
index 283cdaa038..279f4202b6 100644
--- a/EdkModulePkg/Universal/Ebc/Dxe/Ipf/EbcSupport.c
+++ b/EdkModulePkg/Universal/Ebc/Dxe/Ipf/EbcSupport.c
@@ -189,6 +189,7 @@ EbcInterpret (
   return (UINT64) VmContext.R[7];
 }
 
+STATIC
 UINT64
 ExecuteEbcImageEntryPoint (
   IN EFI_HANDLE           ImageHandle,
diff --git a/MdePkg/Library/BaseIoLibIntrinsic/IoHighLevel.c b/MdePkg/Library/BaseIoLibIntrinsic/IoHighLevel.c
index 0d8d0de8f4..ed09b4e5aa 100644
--- a/MdePkg/Library/BaseIoLibIntrinsic/IoHighLevel.c
+++ b/MdePkg/Library/BaseIoLibIntrinsic/IoHighLevel.c
@@ -48,7 +48,7 @@ IoOr8 (
   IN      UINT8                     OrData
   )
 {
-  return IoWrite8 (Port, IoRead8 (Port) | OrData);
+  return IoWrite8 (Port, (UINT8) (IoRead8 (Port) | OrData));
 }
 
 /**
@@ -76,7 +76,7 @@ IoAnd8 (
   IN      UINT8                     AndData
   )
 {
-  return IoWrite8 (Port, IoRead8 (Port) & AndData);
+  return IoWrite8 (Port, (UINT8) (IoRead8 (Port) & AndData));
 }
 
 /**
@@ -107,7 +107,7 @@ IoAndThenOr8 (
   IN      UINT8                     OrData
   )
 {
-  return IoWrite8 (Port, (IoRead8 (Port) & AndData) | OrData);
+  return IoWrite8 (Port, (UINT8) ((IoRead8 (Port) & AndData) | OrData));
 }
 
 /**
@@ -328,7 +328,7 @@ IoOr16 (
   IN      UINT16                    OrData
   )
 {
-  return IoWrite16 (Port, IoRead16 (Port) | OrData);
+  return IoWrite16 (Port, (UINT16) (IoRead16 (Port) | OrData));
 }
 
 /**
@@ -356,7 +356,7 @@ IoAnd16 (
   IN      UINT16                    AndData
   )
 {
-  return IoWrite16 (Port, IoRead16 (Port) & AndData);
+  return IoWrite16 (Port, (UINT16) (IoRead16 (Port) & AndData));
 }
 
 /**
@@ -387,7 +387,7 @@ IoAndThenOr16 (
   IN      UINT16                    OrData
   )
 {
-  return IoWrite16 (Port, (IoRead16 (Port) & AndData) | OrData);
+  return IoWrite16 (Port, (UINT16) ((IoRead16 (Port) & AndData) | OrData));
 }
 
 /**
@@ -1168,7 +1168,7 @@ MmioOr8 (
   IN      UINT8                     OrData
   )
 {
-  return MmioWrite8 (Address, MmioRead8 (Address) | OrData);
+  return MmioWrite8 (Address, (UINT8) (MmioRead8 (Address) | OrData));
 }
 
 /**
@@ -1196,7 +1196,7 @@ MmioAnd8 (
   IN      UINT8                     AndData
   )
 {
-  return MmioWrite8 (Address, MmioRead8 (Address) & AndData);
+  return MmioWrite8 (Address, (UINT8) (MmioRead8 (Address) & AndData));
 }
 
 /**
@@ -1228,7 +1228,7 @@ MmioAndThenOr8 (
   IN      UINT8                     OrData
   )
 {
-  return MmioWrite8 (Address, (MmioRead8 (Address) & AndData) | OrData);
+  return MmioWrite8 (Address, (UINT8) ((MmioRead8 (Address) & AndData) | OrData));
 }
 
 /**
@@ -1450,7 +1450,7 @@ MmioOr16 (
   IN      UINT16                    OrData
   )
 {
-  return MmioWrite16 (Address, MmioRead16 (Address) | OrData);
+  return MmioWrite16 (Address, (UINT16) (MmioRead16 (Address) | OrData));
 }
 
 /**
@@ -1478,7 +1478,7 @@ MmioAnd16 (
   IN      UINT16                    AndData
   )
 {
-  return MmioWrite16 (Address, MmioRead16 (Address) & AndData);
+  return MmioWrite16 (Address, (UINT16) (MmioRead16 (Address) & AndData));
 }
 
 /**
@@ -1510,7 +1510,7 @@ MmioAndThenOr16 (
   IN      UINT16                    OrData
   )
 {
-  return MmioWrite16 (Address, (MmioRead16 (Address) & AndData) | OrData);
+  return MmioWrite16 (Address, (UINT16) ((MmioRead16 (Address) & AndData) | OrData));
 }
 
 /**