IOATACommand

Inherits from
IOCommand
Availability
Available in OS X v10.0 and later.
Declared in
IOATACommand.h

Overview

Command structure superclass, created and freed only by IOATADevice objects populated by disk device drivers with command parameters then submitted for operation to their IOATADevice provider for execution.

IOATACommand is a virtual class, a concrete subclass contains the methods and fields needed by IOATAControllers. Subclasses may be specific to particular controller hardware. Disk device drivers will only have visibility to this interface and may not subclass this object. Disk device drivers should instead make use of the void* refcon field which the controllers will not touch

Tasks

Miscellaneous

Instance Methods

getActualTransfer

The byte count on the ending result, as best as can be determined by the controller. May be zero, but partial transfer may have occurred on error in some cases.

virtual IOByteCount getActualTransfer ( void );

getBuffer

the IOMemoryDescriptor used in this transaction.

virtual IOMemoryDescriptor* getBuffer ( void );

getCommandInUse

returns true if IOATAController is still in control of the command.

virtual bool getCommandInUse( void );

getCylHi

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual UInt8 getCylHi ( void );

getCylLo

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual UInt8 getCylLo ( void );

getDevice_Head

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual UInt8 getDevice_Head ( void );

getEndErrorReg

If the error bit was set in the status register, the value of the error register is returned at the end of a command.

virtual UInt8 getEndErrorReg( void );

getEndStatusReg

the value of the status register on the end of the command.

virtual UInt8 getEndStatusReg ( void);

getErrorReg

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual UInt8 getErrorReg ( void );

getResult

IOReturn value of the result of this command. ATA family errors are defined in IOATATypes.h

virtual IOReturn getResult ( void);

getSectorCount

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual UInt8 getSectorCount ( void );

getSectorNumber

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual UInt8 getSectorNumber ( void );

getStatus

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual UInt8 getStatus ( void );

setBuffer

set the IIOMemoryDescriptor for this transaction.

virtual void setBuffer ( IOMemoryDescriptor *inDesc);

setByteCount

set the byte count for this transaction. Should agree with the device command and the memory descriptor in use.

virtual void setByteCount ( IOByteCount numBytes);

setCallbackPtr

set the function pointer to call when this command completes.

virtual void setCallbackPtr ( IOATACompletionFunction *inCompletion);

setCommand

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual void setCommand ( UInt8 in);

setCylHi

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual void setCylHi( UInt8 in);

setCylLo

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual void setCylLo ( UInt8 in);

setDevice_Head

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual void setDevice_Head( UInt8 in);

setFeatures

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual void setFeatures( UInt8 in);

setFlags

set the flags for this command, as defined in IOATATypes.

virtual void setFlags( UInt32 inFlags);

setLBA28

convenience method that sets the taskfile registers into a 28-bit LBA address, with unit selected and LBA bit set. return err if param out of range, return kIOSuccess (kATANoErr) = 0 on return if successful

virtual IOReturn setLBA28( UInt32 lba, ataUnitID inUnit);

setOpcode

command opcode as defined in IOATATypes.

virtual void setOpcode( ataOpcode inCode);

setPacketCommand

ATAPI command packet max size is 16 bytes. Makes deep copy of data.

virtual IOReturn setPacketCommand( UInt16 packetSizeBytes, UInt8 *command);

setPosition

used to set an offset into the memory descriptor for this transfer.

virtual void setPosition ( IOByteCount fromPosition);

setRegMask

used when accessing registers or reading registers on an error result. Mask is defined in IOATATypes.h

virtual void setRegMask( ataRegMask mask);

setSectorCount

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual void setSectorCount( UInt8 in);

setSectorNumber

Taskfile access. Registers are named in accordance with ATA Standards conventions

virtual void setSectorNumber( UInt8 in);

setTimeoutMS

how long to allow this command to complete, in milliseconds, once issued to the hardware. if the time period expires, this command will return with a timeout error.

virtual void setTimeoutMS( UInt32 inMs);

setTransferChunkSize

set the size of transfer between intervening interrupts. necessary when doing PIO Read/Write Multiple, etc. so the controller knows when to expect an interrupt during multi-sector data transfers.

virtual void setTransferChunkSize( IOByteCount chunk = kATADefaultSectorSize);

setUnit

set the unit number for this command.

virtual void setUnit( ataUnitID inUnit);

zeroCommand

set to blank state, MUST call prior to re-use of this object

virtual void zeroCommand( void);

ExpansionData

struct ExpansionData {
   IOExtendedLBA *extLBA;
};
Discussion

This structure will be used to expand the capablilties of the IOWorkLoop in the future.

Instance Variables

fExpansionData

ExpansionData *fExpansionData;

Reserved for future use. (Internal use only)

See Also

refCon

for use by disk drivers, clients of IOATADevice only. IOATADevice and IOATAControllers shall not use this field in any manner.

void* refCon;

for use by disk drivers, clients of IOATADevice only. IOATADevice and IOATAControllers shall not use this field in any manner.

refCon2

for use by disk drivers, clients of IOATADevice only. IOATADevice and IOATAControllers shall not use this field in any manner.

void* refCon2;

for use by disk drivers, clients of IOATADevice only. IOATADevice and IOATAControllers shall not use this field in any manner.

reserved

ExpansionData *fExpansionData;

Reserved for future use. (Internal use only)

See Also