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diff --git a/Omap35xxPkg/SmbusDxe/Smbus.c b/Omap35xxPkg/SmbusDxe/Smbus.c
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+/** @file
+
+ Copyright (c) 2008-2009, Apple Inc. All rights reserved.
+
+ All rights reserved. This program and the accompanying materials
+ are licensed and made available under the terms and conditions of the BSD License
+ which accompanies this distribution. The full text of the license may be found at
+ http://opensource.org/licenses/bsd-license.php
+
+ THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#include <Uefi.h>
+#include <Omap3530/Omap3530.h>
+
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+
+#include <Protocol/SmbusHc.h>
+
+#define MAX_RETRY 1000
+
+//
+// Internal Functions
+//
+STATIC
+EFI_STATUS
+WaitForBusBusy (
+ VOID
+ )
+{
+ UINTN Retry = 0;
+
+ while (++Retry < MAX_RETRY && (MmioRead16(I2C_STAT) & BB) == 0x1);
+
+ if (Retry == MAX_RETRY) {
+ return EFI_TIMEOUT;
+ }
+
+ return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+PollForStatus(
+ UINT16 StatusBit
+ )
+{
+ UINTN Retry = 0;
+
+ while(Retry < MAX_RETRY) {
+ if (MmioRead16(I2C_STAT) & StatusBit) {
+ //Clear particular status bit from Status register.
+ MmioOr16(I2C_STAT, StatusBit);
+ break;
+ }
+ Retry++;
+ }
+
+ if (Retry == MAX_RETRY) {
+ return EFI_TIMEOUT;
+ }
+
+ return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+ConfigureI2c (
+ VOID
+ )
+{
+ //Program prescaler to obtain 12-MHz clock
+ MmioWrite16(I2C_PSC, 0x0000);
+
+ //Program SCLL and SCLH
+ //NOTE: Following values are the register dump after U-Boot code executed.
+ //We need to figure out how its calculated based on the I2C functional clock and I2C_PSC.
+ MmioWrite16(I2C_SCLL, 0x0035);
+ MmioWrite16(I2C_SCLH, 0x0035);
+
+ //Take the I2C controller out of reset.
+ MmioOr16(I2C_CON, I2C_EN);
+
+ //Initialize the I2C controller.
+
+ //Set I2C controller in Master mode.
+ MmioOr16(I2C_CON, MST);
+
+ //Enable interrupts for receive/transmit mode.
+ MmioOr16(I2C_IE, (XRDY_IE | RRDY_IE | ARDY_IE | NACK_IE));
+
+ return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+I2CReadOneByte (
+ UINT8 *Data
+ )
+{
+ EFI_STATUS Status;
+
+ //I2C bus status checking
+ Status = WaitForBusBusy();
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+
+ //Poll till Receive ready bit is set.
+ Status = PollForStatus(RRDY);
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+
+ *Data = MmioRead8(I2C_DATA);
+
+ return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+I2CWriteOneByte (
+ UINT8 Data
+ )
+{
+ EFI_STATUS Status;
+
+ //I2C bus status checking
+ Status = WaitForBusBusy();
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+
+ //Data transfer
+ //Poll till Transmit ready bit is set
+ Status = PollForStatus(XRDY);
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+
+ MmioWrite8(I2C_DATA, Data);
+
+ //Wait and check if the NACK is not set.
+ gBS->Stall(1000);
+ if (MmioRead16(I2C_STAT) & NACK) {
+ return EFI_DEVICE_ERROR;
+ }
+
+ return EFI_SUCCESS;
+}
+
+STATIC
+EFI_STATUS
+SmbusBlockRead (
+ OUT UINT8 *Buffer,
+ IN UINTN Length
+ )
+{
+ UINTN Index = 0;
+ EFI_STATUS Status = EFI_SUCCESS;
+
+ //Transfer configuration for receiving data.
+ MmioWrite16(I2C_CNT, Length);
+ //Need stop bit before sending data.
+ MmioWrite16(I2C_CON, (I2C_EN | MST | STP | STT));
+
+ while (Index < Length) {
+ //Read a byte
+ Status = I2CReadOneByte(&Buffer[Index++]);
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+ }
+
+ //Transfer completion
+ Status = PollForStatus(ARDY);
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+
+ return Status;
+}
+
+STATIC
+EFI_STATUS
+SmbusBlockWrite (
+ IN UINT8 *Buffer,
+ IN UINTN Length
+ )
+{
+ UINTN Index = 0;
+ EFI_STATUS Status = EFI_SUCCESS;
+
+ //Transfer configuration for transmitting data
+ MmioWrite16(I2C_CNT, Length);
+ MmioWrite16(I2C_CON, (I2C_EN | TRX | MST | STT | STP));
+
+ while (Index < Length) {
+ //Send a byte
+ Status = I2CWriteOneByte(Buffer[Index++]);
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+ }
+
+ //Transfer completion
+ Status = PollForStatus(ARDY);
+ if (EFI_ERROR(Status)) {
+ return Status;
+ }
+
+ return Status;
+}
+
+//
+// Public Functions.
+//
+EFI_STATUS
+EFIAPI
+SmbusExecute (
+ IN CONST EFI_SMBUS_HC_PROTOCOL *This,
+ IN CONST EFI_SMBUS_DEVICE_ADDRESS SlaveAddress,
+ IN CONST EFI_SMBUS_DEVICE_COMMAND Command,
+ IN CONST EFI_SMBUS_OPERATION Operation,
+ IN CONST BOOLEAN PecCheck,
+ IN OUT UINTN *Length,
+ IN OUT VOID *Buffer
+ )
+{
+ UINT8 *ByteBuffer = Buffer;
+ EFI_STATUS Status = EFI_SUCCESS;
+ UINT8 SlaveAddr = (UINT8)(SlaveAddress.SmbusDeviceAddress);
+
+ if (PecCheck) {
+ return EFI_UNSUPPORTED;
+ }
+
+ if ((Operation != EfiSmbusWriteBlock) && (Operation != EfiSmbusReadBlock)) {
+ return EFI_UNSUPPORTED;
+ }
+
+ //Set the Slave address.
+ MmioWrite16(I2C_SA, SlaveAddr);
+
+ if (Operation == EfiSmbusReadBlock) {
+ Status = SmbusBlockRead(ByteBuffer, *Length);
+ } else if (Operation == EfiSmbusWriteBlock) {
+ Status = SmbusBlockWrite(ByteBuffer, *Length);
+ }
+
+ return Status;
+}
+
+EFI_STATUS
+EFIAPI
+SmbusArpDevice (
+ IN CONST EFI_SMBUS_HC_PROTOCOL *This,
+ IN CONST BOOLEAN ArpAll,
+ IN CONST EFI_SMBUS_UDID *SmbusUdid OPTIONAL,
+ IN OUT EFI_SMBUS_DEVICE_ADDRESS *SlaveAddress OPTIONAL
+ )
+{
+ return EFI_UNSUPPORTED;
+}
+
+
+EFI_STATUS
+EFIAPI
+SmbusGetArpMap (
+ IN CONST EFI_SMBUS_HC_PROTOCOL *This,
+ IN OUT UINTN *Length,
+ IN OUT EFI_SMBUS_DEVICE_MAP **SmbusDeviceMap
+ )
+{
+ return EFI_UNSUPPORTED;
+}
+
+
+EFI_STATUS
+EFIAPI
+SmbusNotify (
+ IN CONST EFI_SMBUS_HC_PROTOCOL *This,
+ IN CONST EFI_SMBUS_DEVICE_ADDRESS SlaveAddress,
+ IN CONST UINTN Data,
+ IN CONST EFI_SMBUS_NOTIFY_FUNCTION NotifyFunction
+ )
+{
+ return EFI_UNSUPPORTED;
+}
+
+EFI_SMBUS_HC_PROTOCOL SmbusProtocol =
+{
+ SmbusExecute,
+ SmbusArpDevice,
+ SmbusGetArpMap,
+ SmbusNotify
+};
+
+EFI_STATUS
+InitializeSmbus (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_HANDLE Handle = NULL;
+ EFI_STATUS Status;
+
+ //Configure I2C controller.
+ Status = ConfigureI2c();
+ if (EFI_ERROR(Status)) {
+ DEBUG ((EFI_D_ERROR, "InitializeI2c fails.\n"));
+ return Status;
+ }
+
+ // Install the SMBUS interface
+ Status = gBS->InstallMultipleProtocolInterfaces(&Handle, &gEfiSmbusHcProtocolGuid, &SmbusProtocol, NULL);
+ ASSERT_EFI_ERROR(Status);
+
+ return Status;
+}
+