I2cMaster.h File Reference

Data Structures
struct	_EFI_PEI_I2C_MASTER_PPI

Macros
#define	EFI_PEI_I2C_MASTER_PPI_GUID   { 0xb3bfab9b, 0x9f9c, 0x4e8b, { 0xad, 0x37, 0x7f, 0x8c, 0x51, 0xfc, 0x62, 0x80 }}

Typedefs
typedef struct _EFI_PEI_I2C_MASTER_PPI	EFI_PEI_I2C_MASTER_PPI
typedef IN UINTN *	BusClockHertz
typedef IN UINTN	SlaveAddress
typedef IN UINTN IN EFI_I2C_REQUEST_PACKET *	RequestPacket

Functions
typedef	EFI_STATUS (EFIAPI *EFI_PEI_I2C_MASTER_PPI_SET_BUS_FREQUENCY)(IN EFI_PEI_I2C_MASTER_PPI *This

Variables
EFI_GUID	gEfiPeiI2cMasterPpiGuid

Detailed Description

This PPI manipulates the I2C host controller to perform transactions as a master on the I2C bus using the current state of any switches or multiplexers in the I2C bus.

Copyright (c) 2013 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Revision Reference:

This PPI is introduced in PI Version 1.3.

Macro Definition Documentation

#define EFI_PEI_I2C_MASTER_PPI_GUID   { 0xb3bfab9b, 0x9f9c, 0x4e8b, { 0xad, 0x37, 0x7f, 0x8c, 0x51, 0xfc, 0x62, 0x80 }}

Typedef Documentation

typedef IN UINTN* BusClockHertz

typedef struct _EFI_PEI_I2C_MASTER_PPI EFI_PEI_I2C_MASTER_PPI

typedef IN UINTN IN EFI_I2C_REQUEST_PACKET* RequestPacket

typedef IN UINTN SlaveAddress

Function Documentation

typedef EFI_STATUS

(

EFIAPI *

EFI_PEI_I2C_MASTER_PPI_START_REQUEST

)

Set the frequency for the I2C clock line.

Parameters

This	Pointer to an EFI_PEI_I2C_MASTER_PPI structure.
BusClockHertz	Pointer to the requested I2C bus clock frequency in Hertz. Upon return this value contains the actual frequency in use by the I2C controller.

Return values

EFI_SUCCESS	The bus frequency was set successfully.
EFI_INVALID_PARAMETER	BusClockHertz is NULL
EFI_UNSUPPORTED	The controller does not support this frequency.

Reset the I2C controller and configure it for use.

Parameters

This	Pointer to an EFI_PEI_I2C_MASTER_PPI structure.

Return values

EFI_SUCCESS	The reset completed successfully.
EFI_DEVICE_ERROR	The reset operation failed.

Start an I2C transaction on the host controller.

Parameters

This	Pointer to an EFI_PEI_I2C_MASTER_PPI structure.
SlaveAddress	Address of the device on the I2C bus. Set the I2C_ADDRESSING_10_BIT when using 10-bit addresses, clear this bit for 7-bit addressing. Bits 0-6 are used for 7-bit I2C slave addresses and bits 0-9 are used for 10-bit I2C slave addresses.
RequestPacket	Pointer to an EFI_I2C_REQUEST_PACKET structure describing the I2C transaction.

Return values

EFI_SUCCESS	The transaction completed successfully.
EFI_BAD_BUFFER_SIZE	The RequestPacket->LengthInBytes value is too large.
EFI_DEVICE_ERROR	There was an I2C error (NACK) during the transaction.
EFI_INVALID_PARAMETER	RequestPacket is NULL
EFI_NO_RESPONSE	The I2C device is not responding to the slave address. EFI_DEVICE_ERROR will be returned if the controller cannot distinguish when the NACK occurred.
EFI_NOT_FOUND	Reserved bit set in the SlaveAddress parameter
EFI_OUT_OF_RESOURCES	Insufficient memory for I2C transaction
EFI_UNSUPPORTED	The controller does not support the requested transaction.

Variable Documentation

EFI_GUID gEfiPeiI2cMasterPpiGuid