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IOATABusCommand

Overview

ATA Device (disk) drivers should use the superclass, IOATACommand and may not derive or use any subclass of IOATACommand.

IOATABusCommand is the subclass of IOATACommand used by IOATAControllers. Controller classes may override this class to provide additional fields as their needs dictate or may use this as a concrete class if it is sufficient.

IOATAControllers are always paired with specific IOATADevices and each specific subclass of IOATADevice is in turn the factory method for IOATACommands for use by disk drivers.

In this manner, mass-storage device drivers (disk drivers, clients of ATA bus controllers) see only the generalized interface of IOATADevice and the generalized interface of IOATACommand. This provides isolation from specific bus details for disk drivers and offers flexibility to controllers to add per-command fields and state variables for their own internal use.

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Functions

allocateCmd

Factory method that creates an instance of this class used by subclasses of IOATADevice.

executeCallback

Calls the completion callback function.

getBuffer

Gets pointer to the memory descriptor for this transaction.

getByteCount

Returns the byte count for this transaction to transfer.

getCallbackPtr

Returns the callback pointer.

getFlags

Returns the flags for this command.

getOpcode

Returns the command opcode.

getPacketData

Returns pointer to the array of packet data.

getPacketSize

Returns the size of ATAPI packet if any.

getPosition

Gets the position within the memory buffer for the transaction.

getRegMask

Gets the register mask for desired regs

getTaskFilePtr

Returns the taskfile structure pointer.

getTimeoutMS

Returns the timeout value for this command.

getTransferChunkSize

Returns the number of bytes between interrupts.

getUnit

Returns the unit ID (0 master, 1 slave).

init

Zeroes all data, returns false if allocation fails. protected.

setActualTransfer

Sets the byte count of bytes actually transferred.

setCommandInUse

Marks the command as being in progress.

setResult

Sets the result code.

zeroCommand

Sets to blank state.

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allocateCmd

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Factory method that creates an instance of this class used by subclasses of IOATADevice.

public

static IOATABusCommand* allocateCmd(
    void); 

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executeCallback

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Calls the completion callback function.

public

virtual void executeCallback(
    void); 

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getBuffer

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Gets pointer to the memory descriptor for this transaction.

public

virtual IOMemoryDescriptor* getBuffer (
    void); 

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getByteCount

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Returns the byte count for this transaction to transfer.

public

virtual IOByteCount getByteCount (
    void); 

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getCallbackPtr

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Returns the callback pointer.

public

virtual IOATACompletionFunction* getCallbackPtr (
    void ); 

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getFlags

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Returns the flags for this command.

public

virtual ataFlags getFlags (
    void ); 

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getOpcode

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Returns the command opcode.

public

virtual ataOpcode getOpcode(
    void ); 

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getPacketData

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Returns pointer to the array of packet data.

public

virtual UInt16* getPacketData(
    void); 

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getPacketSize

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Returns the size of ATAPI packet if any.

public

virtual UInt16 getPacketSize(
    void); 

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getPosition

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Gets the position within the memory buffer for the transaction.

public

virtual IOByteCount getPosition (
    void); 

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getRegMask

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Gets the register mask for desired regs

public

virtual ataRegMask getRegMask(
    void ); 

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getTaskFilePtr

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Returns the taskfile structure pointer.

public

virtual ataTaskFile* getTaskFilePtr(
    void); 

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getTimeoutMS

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Returns the timeout value for this command.

public

virtual UInt32 getTimeoutMS (
    void ); 

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getTransferChunkSize

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Returns the number of bytes between interrupts.

public

virtual IOByteCount getTransferChunkSize(
    void); 

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getUnit

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Returns the unit ID (0 master, 1 slave).

public

virtual ataUnitID getUnit(
    void ); 

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init

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Zeroes all data, returns false if allocation fails. protected.

protected

virtual bool init(); 

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setActualTransfer

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Sets the byte count of bytes actually transferred.

public

virtual void setActualTransfer (
    IOByteCount bytesTransferred ); 

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setCommandInUse

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Marks the command as being in progress.

public

virtual void setCommandInUse(
    bool inUse = true); 

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setResult

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Sets the result code.

public

virtual void setResult(
    IOReturn ); 

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zeroCommand

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Sets to blank state.

public

virtual void zeroCommand(
    void); 

Discussion

Call this method prior to re-use of this object.

Structs and Unions

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ExpansionData

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protected

struct ExpansionData {
}; 

Discussion

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

Member Data

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queueChain

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public

queue_chain_t queueChain; 

Discussion

Queue header for use by IOATAController.

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reserved

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protected

ExpansionData *reserved; 

Discussion

Reserved for future use. (Internal use only)

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state

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public

UInt32 state; 

Discussion

State-semaphore for use by IOATAController.

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syncer

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public

IOSyncer* syncer; 

Discussion

IOSyncer for use by IOATAController.

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Last Updated: 2008-12-19