/** @file
Common code to implement SMBus bus protocols. Smbus PEI and DXE modules
share the same version of this file.
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.
**/
#include "CommonHeader.h"
#include "QNCSmbus.h"
/**
Checks the parameter of SmbusExecute().
This function checks the input parameters of SmbusExecute(). If the input parameters are valid
for certain SMBus bus protocol, it will return EFI_SUCCESS; otherwise, it will return certain
error code based on the input SMBus bus protocol.
@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. It can mean the offset to a list of functions inside an
SMBus slave device. Not all operations or slave devices support
this command's registers.
@param Operation Signifies which particular SMBus hardware protocol instance that
it will use to execute the SMBus transactions. This SMBus
hardware protocol is defined by the SMBus Specification and is
not related to EFI.
@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. The
maximum number of bytes can be revision specific and operation
specific. This field will contain the actual number of bytes that
are executed for this operation. Not all operations require this
argument.
@param Buffer Contains the value of data to execute to the SMBus slave device.
Not all operations require this argument. The length of this
buffer is identified by Length.
@retval EFI_SUCCESS All the parameters are valid for the corresponding SMBus bus
protocol.
@retval EFI_INVALID_PARAMETER Operation is not defined in EFI_SMBUS_OPERATION.
@retval EFI_INVALID_PARAMETER 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.
**/
EFI_STATUS
QncSmbusExecCheckParameters (
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
)
{
EFI_STATUS Status;
UINTN RequiredLen;
//
// Set default value to be 2:
// for SmbusReadWord, SmbusWriteWord and SmbusProcessCall.
//
RequiredLen = 2;
Status = EFI_SUCCESS;
switch (Operation) {
case EfiSmbusQuickRead:
case EfiSmbusQuickWrite:
if (PecCheck || Command != 0) {
return EFI_UNSUPPORTED;
}
break;
case EfiSmbusReceiveByte:
case EfiSmbusSendByte:
if (Command != 0) {
return EFI_UNSUPPORTED;
}
//
// Cascade to check length parameter.
//
case EfiSmbusReadByte:
case EfiSmbusWriteByte:
RequiredLen = 1;
//
// Cascade to check length parameter.
//
case EfiSmbusReadWord:
case EfiSmbusWriteWord:
case EfiSmbusProcessCall:
if (Buffer == NULL || Length == NULL) {
return EFI_INVALID_PARAMETER;
} else if (*Length < RequiredLen) {
Status = EFI_BUFFER_TOO_SMALL;
}
*Length = RequiredLen;
break;
case EfiSmbusReadBlock:
case EfiSmbusWriteBlock:
if ((Buffer == NULL) ||
(Length == NULL) ||
(*Length < MIN_SMBUS_BLOCK_LEN) ||
(*Length > MAX_SMBUS_BLOCK_LEN)) {
return EFI_INVALID_PARAMETER;
}
break;
case EfiSmbusBWBRProcessCall:
return EFI_UNSUPPORTED;
default:
return EFI_INVALID_PARAMETER;
}
return Status;
}
/**
Executes an SMBus operation to an SMBus controller. Returns when either the command has been
executed or an error is encountered in doing the operation.
The internal worker function provides a standard way to execute an operation as defined in the
System Management Bus (SMBus) Specification. The resulting transaction will be either that the
SMBus slave devices accept this transaction or that this function returns with error.
@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. It can mean the offset to a list of functions inside an
SMBus slave device. Not all operations or slave devices support
this command's registers.
@param Operation Signifies which particular SMBus hardware protocol instance that
it will use to execute the SMBus transactions. This SMBus
hardware protocol is defined by the SMBus Specification and is
not related to EFI.
@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. The
maximum number of bytes can be revision specific and operation
specific. This field will contain the actual number of bytes that
are executed for this operation. Not all operations require this
argument.
@param Buffer Contains the value of data to execute to the SMBus slave device.
Not all operations require this argument. The length of this
buffer is identified by Length.
@retval EFI_SUCCESS The last data that was returned from the access matched the poll
exit criteria.
@retval EFI_CRC_ERROR 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 that was
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).
@retval EFI_INVALID_PARAMETER Operation is not defined in EFI_SMBUS_OPERATION.
@retval EFI_INVALID_PARAMETER 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.
**/
EFI_STATUS
Execute (
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
)
{
EFI_STATUS Status;
UINTN SmbusAddress;
UINTN WorkBufferLen;
UINT8 WorkBuffer[MAX_SMBUS_BLOCK_LEN];
Status = QncSmbusExecCheckParameters (
SlaveAddress,
Command,
Operation,
PecCheck,
Length,
Buffer);
if (EFI_ERROR (Status)) {
return Status;
}
SmbusAddress = SMBUS_LIB_ADDRESS (SlaveAddress.SmbusDeviceAddress, Command, *Length, PecCheck);
switch (Operation) {
case EfiSmbusQuickRead:
SmBusQuickRead (SmbusAddress, &Status);
break;
case EfiSmbusQuickWrite:
SmBusQuickWrite (SmbusAddress, &Status);
break;
case EfiSmbusReceiveByte:
*(UINT8 *) Buffer = SmBusReceiveByte (SmbusAddress, &Status);
break;
case EfiSmbusSendByte:
SmBusSendByte (SmbusAddress, *(UINT8 *) Buffer, &Status);
break;
case EfiSmbusReadByte:
*(UINT8 *) Buffer = SmBusReadDataByte (SmbusAddress, &Status);
break;
case EfiSmbusWriteByte:
SmBusWriteDataByte (SmbusAddress, *(UINT8 *) Buffer, &Status);
break;
case EfiSmbusReadWord:
*(UINT16 *) Buffer = SmBusReadDataWord (SmbusAddress, &Status);
break;
case EfiSmbusWriteWord:
SmBusWriteDataWord (SmbusAddress, *(UINT16 *) Buffer, &Status);
break;
case EfiSmbusProcessCall:
*(UINT16 *) Buffer = SmBusProcessCall (SmbusAddress, *(UINT16 *) Buffer, &Status);
break;
case EfiSmbusReadBlock:
WorkBufferLen = SmBusReadBlock (SmbusAddress, WorkBuffer, &Status);
if (!EFI_ERROR (Status)) {
//
// Read block transaction is complete successfully, and then
// check whether the output buffer is large enough.
//
if (*Length >= WorkBufferLen) {
CopyMem (Buffer, WorkBuffer, WorkBufferLen);
} else {
Status = EFI_BUFFER_TOO_SMALL;
}
*Length = WorkBufferLen;
}
break;
case EfiSmbusWriteBlock:
SmBusWriteBlock (ADD_LENGTH (SmbusAddress, *Length), Buffer, &Status);
break;
default:
break;
}
return Status;
}