SmbusLib.h File Reference

Macros
#define	SMBUS_LIB_ADDRESS(SlaveAddress, Command, Length, Pec)
#define	SMBUS_LIB_SLAVE_ADDRESS(SmBusAddress)   (((SmBusAddress) >> 1) & 0x7f)
#define	SMBUS_LIB_COMMAND(SmBusAddress)   (((SmBusAddress) >> 8) & 0xff)
#define	SMBUS_LIB_LENGTH(SmBusAddress)   (((SmBusAddress) >> 16) & 0x3f)
#define	SMBUS_LIB_PEC(SmBusAddress)   ((BOOLEAN) (((SmBusAddress) & BIT22) != 0))
#define	SMBUS_LIB_RESERVED(SmBusAddress)   ((SmBusAddress) & ~(BIT23 - 2))

Functions
VOID EFIAPI	SmBusQuickRead (IN UINTN SmBusAddress, OUT RETURN_STATUS *Status)
VOID EFIAPI	SmBusQuickWrite (IN UINTN SmBusAddress, OUT RETURN_STATUS *Status)
UINT8 EFIAPI	SmBusReceiveByte (IN UINTN SmBusAddress, OUT RETURN_STATUS *Status)
UINT8 EFIAPI	SmBusSendByte (IN UINTN SmBusAddress, IN UINT8 Value, OUT RETURN_STATUS *Status)
UINT8 EFIAPI	SmBusReadDataByte (IN UINTN SmBusAddress, OUT RETURN_STATUS *Status)
UINT8 EFIAPI	SmBusWriteDataByte (IN UINTN SmBusAddress, IN UINT8 Value, OUT RETURN_STATUS *Status)
UINT16 EFIAPI	SmBusReadDataWord (IN UINTN SmBusAddress, OUT RETURN_STATUS *Status)
UINT16 EFIAPI	SmBusWriteDataWord (IN UINTN SmBusAddress, IN UINT16 Value, OUT RETURN_STATUS *Status)
UINT16 EFIAPI	SmBusProcessCall (IN UINTN SmBusAddress, IN UINT16 Value, OUT RETURN_STATUS *Status)
UINTN EFIAPI	SmBusReadBlock (IN UINTN SmBusAddress, OUT VOID *Buffer, OUT RETURN_STATUS *Status)
UINTN EFIAPI	SmBusWriteBlock (IN UINTN SmBusAddress, OUT VOID *Buffer, OUT RETURN_STATUS *Status)
UINTN EFIAPI	SmBusBlockProcessCall (IN UINTN SmBusAddress, IN VOID *WriteBuffer, OUT VOID *ReadBuffer, OUT RETURN_STATUS *Status)

Detailed Description

Provides library functions to access SMBUS devices. Libraries of this class must be ported to a specific SMBUS controller.

Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Macro Definition Documentation

#define SMBUS_LIB_ADDRESS	(		SlaveAddress,
			Command,
			Length,
			Pec
	)

Value:

( ((Pec) ? BIT22: 0)                  | \
    (((SlaveAddress) & 0x7f) << 1)      | \
    (((Command)      & 0xff) << 8)      | \
    (((Length)       & 0x3f) << 16)       \
  )

Macro that converts SMBUS slave address, SMBUS command, SMBUS data length, and PEC to a value that can be passed to the SMBUS Library functions.

Computes an address that is compatible with the SMBUS Library functions. The unused upper bits of SlaveAddress, Command, and Length are stripped prior to the generation of the address.

Parameters

SlaveAddress	SMBUS Slave Address. Range 0..127.
Command	SMBUS Command. Range 0..255.
Length	SMBUS Data Length. Range 0..32.
Pec	TRUE if Packet Error Checking is enabled. Otherwise FALSE.

#define SMBUS_LIB_COMMAND

(

SmBusAddress

)

(((SmBusAddress) >> 8) & 0xff)

Macro that returns the SMBUS Command value from an SmBusAddress Parameter value.

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC

#define SMBUS_LIB_LENGTH

(

SmBusAddress

)

(((SmBusAddress) >> 16) & 0x3f)

Macro that returns the SMBUS Data Length value from an SmBusAddress Parameter value.

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC

#define SMBUS_LIB_PEC

(

SmBusAddress

)

((BOOLEAN) (((SmBusAddress) & BIT22) != 0))

Macro that returns the SMBUS PEC value from an SmBusAddress Parameter value.

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC

#define SMBUS_LIB_RESERVED

(

SmBusAddress

)

((SmBusAddress) & ~(BIT23 - 2))

Macro that returns the set of reserved bits from an SmBusAddress Parameter value.

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC

#define SMBUS_LIB_SLAVE_ADDRESS

(

SmBusAddress

)

(((SmBusAddress) >> 1) & 0x7f)

Macro that returns the SMBUS Slave Address value from an SmBusAddress Parameter value.

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC

Function Documentation

UINTN EFIAPI SmBusBlockProcessCall	(	IN UINTN	SmBusAddress,
		IN VOID *	WriteBuffer,
		OUT VOID *	ReadBuffer,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS block process call command.

Executes an SMBUS block process call command on the SMBUS device specified by SmBusAddress. The SMBUS slave address, SMBUS command, and SMBUS length fields of SmBusAddress are required. Bytes are written to the SMBUS from WriteBuffer. Bytes are then read from the SMBUS into ReadBuffer. If Status is not NULL, then the status of the executed command is returned in Status. It is the caller's responsibility to make sure ReadBuffer is large enough for the total number of bytes read. SMBUS supports a maximum transfer size of 32 bytes, so Buffer does not need to be any larger than 32 bytes. If Length in SmBusAddress is zero or greater than 32, then ASSERT(). If WriteBuffer is NULL, then ASSERT(). If ReadBuffer is NULL, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress	Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.
WriteBuffer	Pointer to the buffer of bytes to write to the SMBUS.
ReadBuffer	Pointer to the buffer of bytes to read from the SMBUS.
Status	Return status for the executed command. This is an optional parameter and may be NULL. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The number of bytes written.

UINT16 EFIAPI SmBusProcessCall	(	IN UINTN	SmBusAddress,
		IN UINT16	Value,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS process call command.

Executes an SMBUS process call command on the SMBUS device specified by SmBusAddress. The 16-bit value specified by Value is written. Only the SMBUS slave address and SMBUS command fields of SmBusAddress are required. The 16-bit value returned by the process call command is returned. If Status is not NULL, then the status of the executed command is returned in Status. If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress	Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.
Value	The 16-bit value to write.
Status	Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The 16-bit value returned by the process call command.

VOID EFIAPI SmBusQuickRead	(	IN UINTN	SmBusAddress,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS quick read command.

Executes an SMBUS quick read command on the SMBUS device specified by SmBusAddress. Only the SMBUS slave address field of SmBusAddress is required. If Status is not NULL, then the status of the executed command is returned in Status. If PEC is set in SmBusAddress, then ASSERT(). If Command in SmBusAddress is not zero, then ASSERT(). If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.

Status

Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_UNSUPPORTED The SMBus operation is not supported.

VOID EFIAPI SmBusQuickWrite	(	IN UINTN	SmBusAddress,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS quick write command.

Executes an SMBUS quick write command on the SMBUS device specified by SmBusAddress. Only the SMBUS slave address field of SmBusAddress is required. If Status is not NULL, then the status of the executed command is returned in Status. If PEC is set in SmBusAddress, then ASSERT(). If Command in SmBusAddress is not zero, then ASSERT(). If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.

Status

Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_UNSUPPORTED The SMBus operation is not supported.

UINTN EFIAPI SmBusReadBlock	(	IN UINTN	SmBusAddress,
		OUT VOID *	Buffer,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS read block command.

Executes an SMBUS read block command on the SMBUS device specified by SmBusAddress. Only the SMBUS slave address and SMBUS command fields of SmBusAddress are required. Bytes are read from the SMBUS and stored in Buffer. The number of bytes read is returned, and will never return a value larger than 32-bytes. If Status is not NULL, then the status of the executed command is returned in Status. It is the caller's responsibility to make sure Buffer is large enough for the total number of bytes read. SMBUS supports a maximum transfer size of 32 bytes, so Buffer does not need to be any larger than 32 bytes. If Length in SmBusAddress is not zero, then ASSERT(). If Buffer is NULL, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress	Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.
Buffer	Pointer to the buffer to store the bytes read from the SMBUS.
Status	Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The number of bytes read.

UINT8 EFIAPI SmBusReadDataByte	(	IN UINTN	SmBusAddress,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS read data byte command.

Executes an SMBUS read data byte command on the SMBUS device specified by SmBusAddress. Only the SMBUS slave address and SMBUS command fields of SmBusAddress are required. The 8-bit value read from the SMBUS is returned. If Status is not NULL, then the status of the executed command is returned in Status. If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.

Status

Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The byte read from the SMBUS.

UINT16 EFIAPI SmBusReadDataWord	(	IN UINTN	SmBusAddress,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS read data word command.

Executes an SMBUS read data word command on the SMBUS device specified by SmBusAddress. Only the SMBUS slave address and SMBUS command fields of SmBusAddress are required. The 16-bit value read from the SMBUS is returned. If Status is not NULL, then the status of the executed command is returned in Status. If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.

Status

Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The byte read from the SMBUS.

UINT8 EFIAPI SmBusReceiveByte	(	IN UINTN	SmBusAddress,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS receive byte command.

Executes an SMBUS receive byte command on the SMBUS device specified by SmBusAddress. Only the SMBUS slave address field of SmBusAddress is required. The byte received from the SMBUS is returned. If Status is not NULL, then the status of the executed command is returned in Status. If Command in SmBusAddress is not zero, then ASSERT(). If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress

Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.

Status

Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The byte received from the SMBUS.

UINT8 EFIAPI SmBusSendByte	(	IN UINTN	SmBusAddress,
		IN UINT8	Value,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS send byte command.

Executes an SMBUS send byte command on the SMBUS device specified by SmBusAddress. The byte specified by Value is sent. Only the SMBUS slave address field of SmBusAddress is required. Value is returned. If Status is not NULL, then the status of the executed command is returned in Status. If Command in SmBusAddress is not zero, then ASSERT(). If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress	Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.
Value	The 8-bit value to send.
Status	Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The parameter of Value.

UINTN EFIAPI SmBusWriteBlock	(	IN UINTN	SmBusAddress,
		OUT VOID *	Buffer,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS write block command.

Executes an SMBUS write block command on the SMBUS device specified by SmBusAddress. The SMBUS slave address, SMBUS command, and SMBUS length fields of SmBusAddress are required. Bytes are written to the SMBUS from Buffer. The number of bytes written is returned, and will never return a value larger than 32-bytes. If Status is not NULL, then the status of the executed command is returned in Status. If Length in SmBusAddress is zero or greater than 32, then ASSERT(). If Buffer is NULL, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress	Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.
Buffer	Pointer to the buffer to store the bytes read from the SMBUS.
Status	Return status for the executed command. This is an optional parameter and may be NULL. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The number of bytes written.

UINT8 EFIAPI SmBusWriteDataByte	(	IN UINTN	SmBusAddress,
		IN UINT8	Value,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS write data byte command.

Executes an SMBUS write data byte command on the SMBUS device specified by SmBusAddress. The 8-bit value specified by Value is written. Only the SMBUS slave address and SMBUS command fields of SmBusAddress are required. Value is returned. If Status is not NULL, then the status of the executed command is returned in Status. If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress	Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.
Value	The 8-bit value to write.
Status	Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The parameter of Value.

UINT16 EFIAPI SmBusWriteDataWord	(	IN UINTN	SmBusAddress,
		IN UINT16	Value,
		OUT RETURN_STATUS *	Status
	)

Executes an SMBUS write data word command.

Executes an SMBUS write data word command on the SMBUS device specified by SmBusAddress. The 16-bit value specified by Value is written. Only the SMBUS slave address and SMBUS command fields of SmBusAddress are required. Value is returned. If Status is not NULL, then the status of the executed command is returned in Status. If Length in SmBusAddress is not zero, then ASSERT(). If any reserved bits of SmBusAddress are set, then ASSERT().

Parameters

SmBusAddress	Address that encodes the SMBUS Slave Address, SMBUS Command, SMBUS Data Length, and PEC.
Value	The 16-bit value to write.
Status	Return status for the executed command. This is an optional parameter and may be NULL. RETURN_SUCCESS The SMBUS command was executed. RETURN_TIMEOUT A timeout occurred while executing the SMBUS command. RETURN_DEVICE_ERROR The request was not completed because a failure reflected in the Host Status Register bit. Device errors are a result of a transaction collision, illegal command field, unclaimed cycle (host initiated), or bus errors (collisions). RETURN_CRC_ERROR The checksum is not correct (PEC is incorrect) RETURN_UNSUPPORTED The SMBus operation is not supported.

Returns

The parameter of Value.