MdePkg/Include/Protocol/Smbus.h

/** @file
  This file declares the EFI SMBus Host Controller protocol

  Copyright (c) 2006, Intel Corporation                                                         
  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.             

  Module Name:  Smbus.h

  @par Revision Reference:
  This protocol is defined in Framework of EFI SMBus Host Controller Specification
  Version 0.9

**/

#ifndef _EFI_SMBUS_H
#define _EFI_SMBUS_H

#define EFI_SMBUS_HC_PROTOCOL_GUID \
  { \
    0xe49d33ed, 0x513d, 0x4634, {0xb6, 0x98, 0x6f, 0x55, 0xaa, 0x75, 0x1c, 0x1b } \
  }

typedef struct _EFI_SMBUS_HC_PROTOCOL EFI_SMBUS_HC_PROTOCOL;

/**
  Executes an SMBus operation to an SMBus controller.

  @param  This A pointer to the EFI_SMBUS_HC_PROTOCOL instance.
  
  @param  SlaveAddress The SMBus slave address of the device with which to communicate.
  
  @param  Command This command is transmitted by the SMBus host 
  controller to the SMBus slave device and the interpretation is 
  SMBus slave device specific.
  
  @param  Operation Signifies which particular SMBus hardware protocol 
  instance that it will use to execute the SMBus transactions. 
  
  @param  PecCheck Defines if Packet Error Code (PEC) checking is required 
  for this operation.
  
  @param  Length Signifies the number of bytes that this operation will do.
  
  @param  Buffer Contains the value of data to execute to the SMBus slave device.

  @retval EFI_SUCCESS The last data that was returned from the access 
  matched the poll exit criteria.
  
  @retval EFI_CRC_ERROR The checksum is not correct (PEC is incorrect)
  
  @retval EFI_TIMEOUT Timeout expired before the operation was completed. 
  Timeout is determined by the SMBus host controller device.
  
  @retval EFI_OUT_OF_RESOURCES The request could not be completed 
  due to a lack of resources.
  
  @retval EFI_DEVICE_ERROR The request was not completed because 
  a failure reflected in the Host Status Register bit.
  
  @retval EFI_INVALID_PARAMETER Operation is not defined in EFI_SMBUS_OPERATION.
  Or Length/Buffer is NULL for operations except for EfiSmbusQuickRead and 
  EfiSmbusQuickWrite. Length is outside the range of valid values.
  
  @retval EFI_UNSUPPORTED The SMBus operation or PEC is not supported.
  
  @retval EFI_BUFFER_TOO_SMALL Buffer is not sufficient for this operation.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_SMBUS_HC_EXECUTE_OPERATION) (
  IN EFI_SMBUS_HC_PROTOCOL              *This,
  IN      EFI_SMBUS_DEVICE_ADDRESS      SlaveAddress,
  IN      EFI_SMBUS_DEVICE_COMMAND      Command,
  IN      EFI_SMBUS_OPERATION           Operation,
  IN      BOOLEAN                       PecCheck,
  IN OUT  UINTN                         *Length,
  IN OUT  VOID                          *Buffer
  );

typedef struct {
  UINT32  VendorSpecificId;
  UINT16  SubsystemDeviceId;
  UINT16  SubsystemVendorId;
  UINT16  Interface;
  UINT16  DeviceId;
  UINT16  VendorId;
  UINT8   VendorRevision;
  UINT8   DeviceCapabilities;
} EFI_SMBUS_UDID;

/**
  CallBack function can be registered in EFI_SMBUS_HC_PROTOCOL_NOTIFY.

  @param  SlaveAddress The SMBUS hardware address to which the SMBUS 
  device is preassigned or allocated.
  
  @param  Data Data of the SMBus host notify command that 
  the caller wants to be called.

  @return Status Code

**/
typedef
EFI_STATUS
(EFIAPI *EFI_SMBUS_NOTIFY_FUNCTION) (
  IN      EFI_SMBUS_DEVICE_ADDRESS      SlaveAddress,
  IN      UINTN                         Data
  );

/**
  Sets the SMBus slave device addresses for the device with a given unique ID 
  or enumerates the entire bus.

  @param  This A pointer to the EFI_SMBUS_HC_PROTOCOL instance.
  
  @param  ArpAll A Boolean expression that indicates if the host drivers need 
  to enumerate all the devices or enumerate only the device that is identified 
  by SmbusUdid. If ArpAll is TRUE, SmbusUdid and SlaveAddress are optional. 
  If ArpAll is FALSE, ArpDevice will enumerate SmbusUdid and the address 
  will be at SlaveAddress.
  
  @param  SmbusUdid The Unique Device Identifier (UDID) that is associated 
  with this device.
  
  @param  SlaveAddress The SMBus slave address that is associated with an SMBus UDID. 

  @retval EFI_SUCCESS The SMBus slave device address was set.
  
  @retval EFI_INVALID_PARAMETER SlaveAddress is NULL.
  
  @retval EFI_OUT_OF_RESOURCES The request could not be completed 
  due to a lack of resources.
  
  @retval EFI_TIMEOUT The SMBus slave device did not respond.
  
  @retval EFI_DEVICE_ERROR The request was not completed because the transaction failed.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_SMBUS_HC_PROTOCOL_ARP_DEVICE) (
  IN EFI_SMBUS_HC_PROTOCOL              *This,
  IN      BOOLEAN                       ArpAll,
  IN      EFI_SMBUS_UDID                *SmbusUdid, OPTIONAL
  IN OUT  EFI_SMBUS_DEVICE_ADDRESS      *SlaveAddress OPTIONAL
  );

typedef struct {
  EFI_SMBUS_DEVICE_ADDRESS  SmbusDeviceAddress;
  EFI_SMBUS_UDID            SmbusDeviceUdid;
} EFI_SMBUS_DEVICE_MAP;

/**
  The GetArpMap() function returns the mapping of all the SMBus devices 
  that are enumerated by the SMBus host driver. 

  @param  This A pointer to the EFI_SMBUS_HC_PROTOCOL instance.
  
  @param  Length Size of the buffer that contains the SMBus device map.
  
  @param  SmbusDeviceMap The pointer to the device map as enumerated 
  by the SMBus controller driver.

  @retval EFI_SUCCESS The device map was returned correctly in the buffer.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_SMBUS_HC_PROTOCOL_GET_ARP_MAP) (
  IN EFI_SMBUS_HC_PROTOCOL              *This,
  IN OUT  UINTN                         *Length,
  IN OUT  EFI_SMBUS_DEVICE_MAP          **SmbusDeviceMap
  );

/**
  The Notify() function registers all the callback functions to allow the 
  bus driver to call these functions when the SlaveAddress/Data pair happens.

  @param  This A pointer to the EFI_SMBUS_HC_PROTOCOL instance.
  
  @param  SlaveAddress Address that the host controller detects as 
  sending a message and calls all the registered functions.
  
  @param  Data Data that the host controller detects as sending a message 
  and calls all the registered functions.
  
  @param  NotifyFunction The function to call when the bus driver 
  detects the SlaveAddress and Data pair.

  @retval EFI_SUCCESS NotifyFunction was registered.

**/
typedef
EFI_STATUS
(EFIAPI *EFI_SMBUS_HC_PROTOCOL_NOTIFY) (
  IN EFI_SMBUS_HC_PROTOCOL              *This,
  IN      EFI_SMBUS_DEVICE_ADDRESS      SlaveAddress,
  IN      UINTN                         Data,
  IN      EFI_SMBUS_NOTIFY_FUNCTION     NotifyFunction
  );

/**
  @par Protocol Description:
  Provides basic SMBus host controller management and basic data 
  transactions over the SMBus.

  @param Execute
  Executes the SMBus operation to an SMBus slave device.

  @param ArpDevice
  Allows an SMBus 2.0 device(s) to be Address Resolution Protocol (ARP)

  @param GetArpMap
  Allows a driver to retrieve the address that was allocated by the SMBus 
  host controller during enumeration/ARP.

  @param Notify
  Allows a driver to register for a callback to the SMBus host 
  controller driver when the bus issues a notification to the bus controller driver.

**/
struct _EFI_SMBUS_HC_PROTOCOL {
  EFI_SMBUS_HC_EXECUTE_OPERATION    Execute;
  EFI_SMBUS_HC_PROTOCOL_ARP_DEVICE  ArpDevice;
  EFI_SMBUS_HC_PROTOCOL_GET_ARP_MAP GetArpMap;
  EFI_SMBUS_HC_PROTOCOL_NOTIFY      Notify;
};

extern EFI_GUID gEfiSmbusProtocolGuid;
#endif