C++程序  |  221行  |  6.24 KB

/** @file
Provides definition of entry point to the common I2C module that produces
common I2C Controller functions used by I2C library services.


Copyright (c) 2013-2015 Intel Corporation.

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.

**/


#ifndef _I2CCOMMON_H_
#define _I2CCOMMON_H_

#include <Uefi.h>
#include <Base.h>

#include <Library/DebugLib.h>
#include <Library/TimerLib.h>
#include <Library/I2cLib.h>
#include <IohAccess.h>
#include <IohCommonDefinitions.h>
#include "I2cRegs.h"

//
// Constants that define I2C Controller timeout and max. polling time.
//
#define MAX_T_POLL_COUNT         100
#define TI2C_POLL                25  // microseconds
#define MAX_STOP_DET_POLL_COUNT ((1000 * 1000) / TI2C_POLL)  // Extreme for expected Stop detect.

/**
  The GetI2CIoPortBaseAddress() function gets IO port base address of I2C Controller.

  Always reads PCI configuration space to get MMIO base address of I2C Controller.

  @return The IO port base address of I2C controller.

**/
UINTN
GetI2CIoPortBaseAddress (
  VOID
  );

/**
  The EnableI2CMmioSpace() function enables access to I2C MMIO space.

**/
VOID
EnableI2CMmioSpace (
  VOID
  );

/**
  The DisableI2CController() functions disables I2C Controller.

**/
VOID
DisableI2CController (
  VOID
  );

/**
  The EnableI2CController() function enables the I2C Controller.

**/
VOID
EnableI2CController (
  VOID
  );

/**
  The WaitForStopDet() function waits until I2C STOP Condition occurs,
  indicating transfer completion.

  @retval EFI_SUCCESS           Stop detected.
  @retval EFI_TIMEOUT           Timeout while waiting for stop condition.
  @retval EFI_ABORTED           Tx abort signaled in HW status register.
  @retval EFI_DEVICE_ERROR      Tx or Rx overflow detected.

**/
EFI_STATUS
WaitForStopDet (
  VOID
  );

/**

  The InitializeInternal() function initialises internal I2C Controller
  register values that are commonly required for I2C Write and Read transfers.

  @param AddrMode     I2C Addressing Mode: 7-bit or 10-bit address.

  @retval EFI_SUCCESS           I2C Operation completed successfully.

**/
EFI_STATUS
InitializeInternal (
  IN EFI_I2C_ADDR_MODE  AddrMode
  );

/**

  The WriteByte() function provides a standard way to execute a
  standard single byte write to an IC2 device (without accessing
  sub-addresses), as defined in the I2C Specification.

  @param  I2CAddress      I2C Slave device address
  @param  Value           The 8-bit value to write.

  @retval EFI_SUCCESS           Transfer success.
  @retval EFI_UNSUPPORTED       Unsupported input param.
  @retval EFI_TIMEOUT           Timeout while waiting xfer.
  @retval EFI_ABORTED           Controller aborted xfer.
  @retval EFI_DEVICE_ERROR      Device error detected by controller.

**/
EFI_STATUS
EFIAPI
WriteByte (
  IN  UINTN          I2CAddress,
  IN  UINT8          Value
  );

/**

  The ReadByte() function provides a standard way to execute a
  standard single byte read to an IC2 device (without accessing
  sub-addresses), as defined in the I2C Specification.

  @param  I2CAddress      I2C Slave device address
  @param  ReturnDataPtr   Pointer to location to receive read byte.

  @retval EFI_SUCCESS           Transfer success.
  @retval EFI_UNSUPPORTED       Unsupported input param.
  @retval EFI_TIMEOUT           Timeout while waiting xfer.
  @retval EFI_ABORTED           Controller aborted xfer.
  @retval EFI_DEVICE_ERROR      Device error detected by controller.

**/
EFI_STATUS
EFIAPI
ReadByte (
  IN  UINTN          I2CAddress,
  OUT UINT8          *ReturnDataPtr
  );

/**

  The WriteMultipleByte() function provides a standard way to execute
  multiple byte writes to an IC2 device (e.g. when accessing sub-addresses or
  when writing block of data), as defined in the I2C Specification.

  @param I2CAddress   The I2C slave address of the device
                      with which to communicate.

  @param WriteBuffer  Contains the value of byte to be written to the
                      I2C slave device.

  @param Length       No. of bytes to be written.

  @retval EFI_SUCCESS           Transfer success.
  @retval EFI_UNSUPPORTED       Unsupported input param.
  @retval EFI_TIMEOUT           Timeout while waiting xfer.
  @retval EFI_ABORTED           Tx abort signaled in HW status register.
  @retval EFI_DEVICE_ERROR      Tx overflow detected.

**/
EFI_STATUS
EFIAPI
WriteMultipleByte (
  IN  UINTN          I2CAddress,
  IN  UINT8          *WriteBuffer,
  IN  UINTN          Length
  );

/**

  The ReadMultipleByte() function provides a standard way to execute
  multiple byte writes to an IC2 device (e.g. when accessing sub-addresses or
  when reading block of data), as defined in the I2C Specification (I2C combined
  write/read protocol).

  @param I2CAddress   The I2C slave address of the device
                      with which to communicate.

  @param Buffer       Contains the value of byte data written or read from the
                      I2C slave device.

  @param WriteLength  No. of bytes to be written. In this case data
                      written typically contains sub-address or sub-addresses
                      in Hi-Lo format, that need to be read (I2C combined
                      write/read protocol).

  @param ReadLength   No. of bytes to be read from I2C slave device.

  @retval EFI_SUCCESS           Transfer success.
  @retval EFI_UNSUPPORTED       Unsupported input param.
  @retval EFI_TIMEOUT           Timeout while waiting xfer.
  @retval EFI_ABORTED           Tx abort signaled in HW status register.
  @retval EFI_DEVICE_ERROR      Rx underflow or Rx/Tx overflow detected.

**/
EFI_STATUS
EFIAPI
ReadMultipleByte (
  IN  UINTN          I2CAddress,
  IN  OUT UINT8      *Buffer,
  IN  UINTN          WriteLength,
  IN  UINTN          ReadLength
  );

#endif