|
ADC Home > Reference Library > Reference > Darwin > Kernel Framework Reference
|
IOService |
| Inherits from: | |
| Declared In: |
The base class for most I/O Kit families, devices, and drivers.
The IOService base class defines APIs used to publish services, instantiate other services based on the existance of a providing service (ie. driver stacking), destroy a service and its dependent stack, notify interested parties of service state changes, and general utility functions useful across all families.
Types of service are specified with a matching dictionary that describes properties of the service. For example, a matching dictionary might describe any IOUSBDevice (or subclass), an IOUSBDevice with a certain class code, or a IOPCIDevice with a set of OpenFirmware matching names or device & vendor IDs. Since the matching dictionary is interpreted by the family which created the service, as well as generically by IOService, the list of properties considered for matching depends on the familiy.
Matching dictionaries are associated with IOService classes by the catalogue, as driver property tables, and also supplied by clients of the notification APIs.
IOService provides matching based on C++ class (via OSMetaClass dynamic casting), registry entry name, a registry path to the service (which includes OpenFirmware paths), a name assigned by BSD, or by its location (its point of attachment).
Driver Instantiation by IOService
Drivers are subclasses of IOService, and their availability is managed through the catalogue. They are instantiated based on the publication of an IOService they use (for example, an IOPCIDevice or IOUSBDevice), or when they are added to the catalogue and the IOService(s) they use are already available.
When an IOService (the "provider") is published with the registerService method, the matching and probing process begins, which is always single threaded per provider. A list of matching dictionaries from the catalog and installed publish notification requests, that successfully match the IOService, is constructed, with ordering supplied by kIOProbeScoreKey ("IOProbeScore") property in the dictionary, or supplied with the notification.
Each entry in the list is then processed in order - for notifications, the notification is delivered, for driver property tables a lot more happens.
The driver class is instantiated and init() called with its property table. The new driver instance is then attached to the provider, and has its probe method called with the provider as an argument. The default probe method does nothing but return success, but a driver may implement this method to interrogate the provider to make sure it can work with it. It may also modify its probe score at this time. After probe, the driver is detached and the next in the list is considered (ie. attached, probed, and detached).
When the probing phase is complete, the list consists of successfully probed drivers, in order of their probe score (after adjustment during the probe call). The list is then divided into categories based on the kIOMatchCategoryKey property ("IOMatchCategory"); drivers without a match category are all considered in one default category. Match categories allow multiple clients of a provider to be attached and started, though the provider may also enforce open/close semantics to gain active access to it.
For each category, the highest scoring driver in that category is attached to the provider, and its start method called. If start is successful, the rest of the drivers in the same match category are discarded, otherwise the next highest scoring driver is started, and so on.
The driver should only consider itself in action when the start method is called, meaning it has been selected for use on the provider, and consuming that particular match category. It should also be prepared to be allocated, probed and freed even if the probe was successful.
After the drivers have all synchronously been started, the installed "matched" notifications that match the registered IOService are delivered.
Properties used by IOService
kIOClassKey, extern const OSSymbol * gIOClassKey, "IOClass"
Class of the driver to instantiate on matching providers.
kIOProviderClassKey, extern const OSSymbol * gIOProviderClassKey, "IOProviderClass"
Class of the provider(s) to be considered for matching, checked with OSDynamicCast so subclasses will also match.
kIOProbeScoreKey, extern const OSSymbol * gIOProbeScoreKey, "IOProbeScore"
The probe score initially used to order multiple matching drivers.
kIOMatchCategoryKey, extern const OSSymbol * gIOMatchCategoryKey, "IOMatchCategory"
A string defining the driver category for matching purposes. All drivers with no IOMatchCategory property are considered to be in the same default category. Only one driver in a category can be started on each provider.
kIONameMatchKey, extern const OSSymbol * gIONameMatchKey, "IONameMatch"
A string or collection of strings that match the provider's name. The comparison is implemented with the IORegistryEntry::compareNames method, which supports a single string, or any collection (OSArray, OSSet, OSDictionary etc.) of strings. IOService objects with OpenFirmware device tree properties (eg. IOPCIDevice) will also be matched based on that standard's "compatible", "name", "device_type" properties. The matching name will be left in the driver's property table in the kIONameMatchedKey property.
Examples
<key>IONameMatch</key> <string>pci106b,7</string>
For a list of possible matching names, a serialized array of strings should used, eg.
<key>IONameMatch</key> <array> <string>APPL,happy16</string> <string>pci106b,7</string> </array>
kIONameMatchedKey, extern const OSSymbol * gIONameMatchedKey, "IONameMatched"
The name successfully matched name from the kIONameMatchKey property will be left in the driver's property table as the kIONameMatchedKey property.
kIOPropertyMatchKey, extern const OSSymbol * gIOPropertyMatchKey, "IOPropertyMatch"
A dictionary of properties that each must exist in the matching IOService and compare successfully with the isEqualTo method.
<key>IOPropertyMatch</key> <dictionary> <key>APPL,happy16</key> <string>APPL,meek8</string> </dictionary>
kIOUserClientClassKey, extern const OSSymbol * gIOUserClientClassKey, "IOUserClientClass"
The class name that the service will attempt to allocate when a user client connection is requested. First the device nub is queried, then the nub's provider is queried by default.
kIOKitDebugKey, extern const OSSymbol * gIOKitDebugKey, "IOKitDebug"
Set some debug flags for logging the driver loading process. Flags are defined in IOKit/IOKitDebug.h, but 65535 works well.
Acknowledges an in-progress power state change.
Acknowledges the belated completion of a driver's setPowerState power state change.
Informs power management when a power-managed device is in use, so that power management can track when it is idle and adjust its power state accordingly.
Adds a location matching property to an existing dictionary.
Adds a persistant notification handler to be notified of IOService events.
Informs a driver that it has a new child.
Adjusts the busyState of an IOService object.
Attaches an IOService client to a provider in the I/O Registry.
Calls the platform function with the given name.
Causes a device interrupt to occur.
Sets a driver's power state.
Tells a driver's superclass to change the power state of its device.
Deprecated. Do not use.
Releases active access to a provider.
Compares a set of properties in a matching dictionary with an IOService object's property table.
Compares a property in a matching dictionary with an IOService object's property table.
Compares a property in a matching dictionary with an IOService object's property table.
Finds out the capability of a device's current power state.
Finds out the current power consumption of a device.
De-registers power state interest from a previous call to registerInterestedDriver.
Detaches an IOService client from a provider in the I/O Registry.
Passes a termination up the stack.
Asks a driver if its device is the one that just woke the system from sleep.
Synchronously disables a device interrupt.
Enables a device interrupt.
Translates an IOReturn code to a BSD errno.
Finalizes the destruction of an IOService object.
Frees data structures that were allocated when power management was initialized on this service.
Returns the current aggressiveness value for the given type.
Returns the busyState of an IOService object.
Returns an IOService object's primary client.
Returns an iterator over an IOService object's clients.
Returns the array of IODeviceMemory objects representing a device's memory mapped ranges.
Returns a count of the physical memory ranges available for a device.
Returns an instance of IODeviceMemory representing one of a device's memory mapped ranges.
Returns the type of interrupt used for a device supplying hardware interrupts.
Finds the set of current published IOService objects matching a matching dictionary.
Returns an iterator over a provider's clients that currently have opened the provider.
Returns an iterator over an client's providers that are currently opened by the client.
Returns a pointer to the platform expert instance for the computer.
Returns a pointer to the power management root domain instance for the computer.
Returns a pointer to the system-wide power management work loop.
Determines a device's power state.
Returns an IOService object's primary provider.
Returns an iterator over an IOService object's providers.
Allocates any needed resources for a published IOService object before clients attach.
Returns a pointer to the IOResources service.
Returns a pointer to the root of the service plane.
Accessor for IOService state bits, not normally needed or used outside IOService.
Returns the current work loop or provider->getWorkLoop.
Controls the open / close behavior of an IOService object (overrideable by subclasses).
Controls the open / close behavior of an IOService object (overrideable by subclasses).
Controls the open / close behavior of an IOService object (overrideable by subclasses).
Determines which power state a device is in, given the current power domain state.
Adds a persistant notification handler to be notified of IOService events.
Checks if the IOService object has been terminated, and is in the process of being destroyed.
Determines whether a specific, or any, client has an IOService object open.
Joins the driver into the power plane of the I/O Registry .
Locks an IOService object against changes in state or ownership.
Requests that a device become usable.
Maps a physical range of a device.
Allows a registered IOService object to direct location matching.
Allows a registered IOService object to implement family specific matching.
Determines a driver's highest power state possible for a given power domain state.
Receives a generic message delivered from an attached provider.
Sends a generic message to an attached client.
Sends a generic message to all attached clients.
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService name match.
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService name match.
(Deprecated. Do not use.) Tells a power managed driver that the temperature in the thermal zone has changed.
Creates a connection for a non kernel client.
Allows subclasses to customize idle power management behavior.
Requests active access to a provider.
Initializes power management for a driver.
Frees and removes the driver from power management.
Tells a driver when a power change is complete.
Notifies a driver that its power domain is about to change state.
Notifies a driver that its power domain is about to change state.
Allows a driver to disable a power override.
Allows a driver to ignore its children's power management requests and only use changePowerStateToPriv to define its own power state.
Informs interested parties that a device has changed to a different power state.
Determines what power state the device would be in for a given power domain state.
Informs interested parties that a device is about to change its power state.
During an IOService object's instantiation, probes a matched service to see if it can be used.
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService phandle match.
Uses the resource service to publish a property.
Uses the resource service to publish a property.
Allows an IOService object to register interest in the changing power state of a power-managed IOService object.
Registers a C function interrupt handler for a device supplying interrupts.
Registers a set of power states that the driver supports.
Starts the registration process for a newly discovered IOService object.
Informs a power managed driver that one of its power plane childen is disappearing.
Tells a driver to adjust its power state.
Requests that hardware be re-scanned for devices.
Passes a termination up the stack.
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify a resource service match.
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify a resource service match.
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService class match.
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService class match.
Broadcasts an aggressiveness factor from the parent of a driver to the driver.
Sets the array of IODeviceMemory objects representing a device's memory mapped ranges.
Sets or changes the idle timer period.
For internal use only; deprecated; not intended to be called or overridden.
Requests a power managed driver to change the power state of its device.
During an IOService object's instantiation, starts the IOService object that has been selected to run on the provider.
During an IOService termination, the stop method is called in its clients before they are detached & it is destroyed.
Supplies a programmer-friendly string from an IOReturn code.
Tells every driver in the power plane that the system is waking up.
Notifies members of the power plane of system shutdown and restart.
Alerts a driver to a critical temperature in some thermal zone.
A driver calls this method to hold itself in the highest power state until it has children.
Makes an IOService object inactive and begins its destruction.
Passes a termination up the stack.
Unlocks an IOService obkect after a successful lockForArbitration.
Removes a C function interrupt handler for a device supplying hardware interrupts.
Waits for a matching to service to be published.
Waits for an IOService object's busyState to be zero.
Passes a termination up the stack.
Informs the root power domain IOService object that is is the root power domain.
acknowledgePowerChange |
Acknowledges an in-progress power state change.
public
virtual IOReturn acknowledgePowerChange ( IOService *whichDriver );
whichDriverA pointer to the calling driver. The called object tracks all interested parties to ensure that all have acknowledged the power state change.
IOPMNoErr.
When power management informs an interested object (via powerStateWillChangeTo or powerStateDidChangeTo), the object can return an immediate acknowledgement via a return code, or it may return an indication that it will acknowledge later by calling acknowledgePowerChange.
Interested objects are those that have registered as interested drivers, as well as power plane children of the power changing driver.
A driver that calls registerInterestedDriver must call acknowledgePowerChange, or use an immediate acknowledgement return from powerStateWillChangeTo or powerStateDidChangeTo.
Most drivers do not need to override acknowledgePowerChange.
acknowledgeSetPowerState |
Acknowledges the belated completion of a driver's setPowerState power state change.
public
virtual IOReturn acknowledgeSetPowerState ( void );
IOPMNoErr.
After power management instructs a driver to change its state via setPowerState, that driver must acknowledge the change when its device has completed its transition. The acknowledgement may be immediate, via a return code from setPowerState, or delayed, via this call to acknowledgeSetPowerState.
Any driver that does not return kIOPMAckImplied from its setPowerState implementation must later call acknowledgeSetPowerState.
Most drivers do not need to override acknowledgeSetPowerState.
activityTickle |
Informs power management when a power-managed device is in use, so that power management can track when it is idle and adjust its power state accordingly.
public
virtual bool activityTickle ( unsigned long type, unsigned long stateNumber=0 );
typeWhen type is kIOPMSubclassPolicy, activityTickle is not handled in IOService and should be intercepted by the subclass. When type is kIOPMSuperclassPolicy1, an activity flag is set and the device state is checked. If the device has been powered down, it is powered up again.
stateNumberWhen type is kIOPMSuperclassPolicy1, stateNumber contains the desired power state ordinal for the activity. If the device is in a lower state, the superclass will switch it to this state. This is for devices that can handle some accesses in lower power states; the device is powered up only as far as it needs to be for the activity.
When type is kIOPMSuperclassPolicy1, the superclass returns true if the device is currently in the state specified by stateNumber. If the device is in a lower state and must be powered up, the superclass returns false; in this case the superclass will initiate a power change to power the device up.
The activityTickle method is provided for objects in the system (or for the driver itself) to tell a driver that its device is being used.
The IOService superclass can manage idleness determination with a simple idle timer mechanism and this activityTickle call. To start this up, the driver calls its superclass's setIdleTimerPeriod. This starts a timer for the time interval specified in the call. When the timer expires, the superclass checks to see if there has been any activity since the last timer expiration. (It checks to see if activityTickle has been called). If there has been activity, it restarts the timer, and this process continues. When the timer expires, and there has been no device activity, the superclass lowers the device power state to the next lower state. This can continue until the device is in state zero.
After the device has been powered down by at least one power state, a subsequent call to activityTickle causes the device to be switched to a higher state required for the activity.
If the driver is managing the idleness determination totally on its own, the value of the type parameter should be kIOPMSubclassPolicy, and the driver should override the activityTickle method. The superclass IOService implementation of activityTickle does nothing with the kIOPMSubclassPolicy argument.
addLocation |
Adds a location matching property to an existing dictionary.
public
static OSDictionary * addLocation( OSDictionary *table );
tableThe matching properties are added to the specified dictionary, which must be non-zero.
The location matching dictionary created is returned on success, or zero on failure.
This function creates matching properties that specify the location of a IOService object, as an embedded matching dictionary. This matching will be successful on an IOService object that attached to an IOService object which matches this location matching dictionary.
addNotification |
Adds a persistant notification handler to be notified of IOService events.
public
static IONotifier * addNotification( const OSSymbol * type, OSDictionary * matching, IOServiceNotificationHandler handler, void * target, void * ref = 0, SInt32 priority = 0 );
typeAn OSSymbol identifying the type of notification and IOService state:
gIOPublishNotification Delivered when an IOService object is registered.
gIOFirstPublishNotification Delivered when an IOService object is registered, but only once per IOService instance. Some IOService objects may be reregistered when their state is changed.
gIOMatchedNotification Delivered when an IOService object has been matched with all client drivers, and they have been probed and started.
gIOFirstMatchNotification Delivered when an IOService object has been matched with all client drivers, but only once per IOService instance. Some IOService objects may be reregistered when their state is changed.
gIOTerminatedNotification Delivered after an IOService object has been terminated, during its finalize stage.
matchingA matching dictionary to restrict notifications to only matching IOService objects. The dictionary will be released when the notification is removed, consuming the passed-in reference.
handlerA C function callback to deliver notifications.
targetAn instance reference for the callback's use.
refA reference constant for the callback's use.
priorityA constant ordering all notifications of a each type.
An instance of an IONotifier object that can be used to control or destroy the notification request.
IOService will deliver notifications of changes in state of an IOService object to registered clients. The type of notification is specified by a symbol, for example gIOMatchedNotification or gIOTerminatedNotification, and notifications will only include IOService objects that match the supplied matching dictionary. Notifications are ordered by a priority set with addNotification. When the notification is installed, its handler will be called with each of any currently existing IOService objects that are in the correct state (eg. registered) and match the supplied matching dictionary, avoiding races between finding preexisting and new IOService events. The notification request is identified by an instance of an IONotifier object, through which it can be enabled, disabled, or removed. addNotification consumes a retain count on the matching dictionary when the notification is removed.
addPowerChild |
Informs a driver that it has a new child.
public
virtual IOReturn addPowerChild ( IOService *theChild );
theChildA pointer to the child IOService object.
The Platform Expert uses this method to call a driver and introduce it to a new child.
This call is handled internally by power management. It is not intended to be overridden or called by drivers.
adjustBusy |
Adjusts the busyState of an IOService object.
public
virtual void adjustBusy( SInt32 delta );
deltaThe delta to be applied to the IOService object's busyState.
Applies a delta to an IOService object's busyState. A change in the busyState to or from zero will change the IOService object's provider's busyState by one (in the same direction).
attach |
Attaches an IOService client to a provider in the I/O Registry.
public
virtual bool attach( IOService *provider );
providerThe IOService object which will serve as this object's provider.
false if the provider is inactive or on a resource failure; otherwise true.
This function called in an IOService client enters the client into the I/O Registry as a child of the provider in the service plane. The provider must be active or the attach will fail. Multiple attach calls to the same provider are no-ops and return success. A client may be attached to multiple providers. Entering an object into the I/O Registry retains both the client and provider until they are detached.
callPlatformFunction |
Calls the platform function with the given name.
public
virtual IOReturn callPlatformFunction( const OSSymbol * functionName, bool waitForFunction, void *param1, void *param2, void *param3, void *param4 );
functionNameName of the function to be called. When functionName is a C string, callPlatformFunction converts the C string to an OSSymbol and calls the OSSymbol version of callPlatformFunction. This process can block and should not be used from an interrupt context.
waitForFunctionIf true, callPlatformFunction will not return until the function has been called.
An IOReturn code; kIOReturnSuccess if the function was successfully executed, kIOReturnUnsupported if a service to execute the function could not be found. Other return codes may be returned by the function.
The platform expert or other drivers may implement various functions to control hardware features. callPlatformFunction allows any IOService object to access these functions. Normally callPlatformFunction is called on a service's provider. The provider services the request or passes it to its provider. The system's IOPlatformExpert subclass catches functions it knows about and redirects them into other parts of the service plane. If the IOPlatformExpert subclass cannot execute the function, the base class is called. The IOPlatformExpert base class attempts to find a service to execute the function by looking up the function name in an IOResources name space. A service may publish a service using publishResource(functionName, this). If no service can be found to execute the function an error is returned.
causeInterrupt |
Causes a device interrupt to occur.
public
virtual IOReturn causeInterrupt( int source);
sourceThe index of the interrupt source in the device.
An IOReturn code (kIOReturnNoInterrupt is returned if the source is not valid).
Emulates a hardware interrupt, to be called from task level.
changePowerStateTo |
Sets a driver's power state.
public
virtual IOReturn changePowerStateTo ( unsigned long ordinal );
ordinalThe number of the desired power state in the power state array.
A return code that can be ignored by the caller.
This function is one of several that are used to set a driver's power state. In most circumstances, however, you should call changePowerStateToPriv instead.
Calls to changePowerStateTo, changePowerStateToPriv, and a driver's power children all affect the power state of a driver. For legacy design reasons, they have overlapping functionality. Although you should call changePowerStateToPriv to change your device's power state, you might need to call changePowerStateTo in the following circumstances:
changePowerStateToPriv to change its power state, it should call changePowerStateTo(0) in its start routine to eliminate the influence changePowerStateTo has on power state calculations.
changePowerStateTo in conjunction with setIdleTimerPeriod and activityTickle to idle a driver into a low power state. For a driver with 3 power states, for example, changePowerStateTo(1) sets a minimum level of power state 1, such that the idle timer period may not set your device's power any lower than state 1.
changePowerStateToPriv |
Tells a driver's superclass to change the power state of its device.
protected
IOReturn changePowerStateToPriv ( unsigned long ordinal );
ordinalThe number of the desired power state in the power state array.
A return code that can be ignored by the caller.
A driver uses this method to tell its superclass to change the power state of the device. This is the recommended way to change the power state of a device.
Three things affect driver power state: changePowerStateTo, changePowerStateToPriv, and the desires of the driver's power plane children. Power management puts the device into the maximum state governed by those three entities.
Drivers may eliminate the influence of the changePowerStateTo method on power state one of two ways. See powerOverrideOnPriv to ignore the method's influence, or call changePowerStateTo(0) in the driver's start routine to remove the changePowerStateTo method's power request.
clampPowerOn |
Deprecated. Do not use.
public
virtual void clampPowerOn ( unsigned long duration);
close |
Releases active access to a provider.
public
virtual void close( IOService *forClient, IOOptionBits options = 0 );
forClientDesignates the client of the provider requesting the close.
optionsOptions available for the close. The provider family may implement options for close; IOService defines none.
argFamily specific arguments which are ignored by IOService.
IOService provides generic open and close semantics to track clients of a provider that have established an active datapath. The use of open and close, and rules regarding ownership are family defined, and defined by the handleOpen and handleClose methods in the provider.
compareProperties |
Compares a set of properties in a matching dictionary with an IOService object's property table.
public
virtual bool compareProperties( OSDictionary *matching, OSCollection *keys );
matchingThe matching dictionary, which must be non-zero.
keysA collection (eg. OSSet, OSArray, OSDictionary) which should contain OSStrings (or OSSymbols) that specify the property keys to be compared.
Success if compareProperty returns true for each key in the collection; otherwise failure.
This is a helper function to aid in implementing matchPropertyTable. A collection of dictionary keys specifies properties in a matching dictionary to be compared, with compareProperty, with an IOService object's property table, if compareProperty returns true for each key, success is returned; otherwise failure.
compareProperty(OSDictionary *, const char *) |
Compares a property in a matching dictionary with an IOService object's property table.
public
virtual bool compareProperty( OSDictionary *matching, const char * key );
matchingThe matching dictionary, which must be non-zero.
keyThe dictionary key specifying the property to be compared, as a C string.
true if the property does not exist in the matching table. If the property exists in the matching dictionary but not the IOService property table, failure is returned. Otherwise the result of calling the property from the matching dictionary's isEqualTo method with the IOService property as an argument is returned.
This is a helper function to aid in implementing matchPropertyTable. If the property specified by key exists in the matching dictionary, it is compared with a property of the same name in the IOService object's property table. The comparison is performed with the isEqualTo method. If the property does not exist in the matching table, success is returned. If the property exists in the matching dictionary but not the IOService property table, failure is returned.
compareProperty(OSDictionary *, const OSString *) |
Compares a property in a matching dictionary with an IOService object's property table.
public
virtual bool compareProperty( OSDictionary *matching, const OSString * key );
matchingThe matching dictionary, which must be non-zero.
keyThe dictionary key specifying the property to be compared, as an OSString (which includes OSSymbol).
true if the property does not exist in the matching table. If the property exists in the matching dictionary but not the IOService property table, failure is returned. Otherwise the result of calling the property from the matching dictionary's isEqualTo method with the IOService property as an argument is returned.
This is a helper function to aid in implementing matchPropertyTable. If the property specified by key exists in the matching dictionary, it is compared with a property of the same name in the IOService object's property table. The comparison is performed with the isEqualTo method. If the property does not exist in the matching table, success is returned. If the property exists in the matching dictionary but not the IOService property table, failure is returned.
currentCapability |
Finds out the capability of a device's current power state.
public
virtual IOPMPowerFlags currentCapability ( void );
A copy of the capabilityFlags field for the current power state in the power state array.
currentPowerConsumption |
Finds out the current power consumption of a device.
public
virtual unsigned long currentPowerConsumption ( void );
A copy of the staticPower field for the current power state in the power state array.
Most Mac OS X power managed drivers do not report their power consumption via the staticPower field. Thus this call will not accurately reflect power consumption for most drivers.
deRegisterInterestedDriver |
De-registers power state interest from a previous call to registerInterestedDriver.
public
virtual IOReturn deRegisterInterestedDriver ( IOService *theDriver );
theDriverThe interested driver previously passed into registerInterestedDriver.
A return code that can be ignored by the caller.
Most drivers do not need to override deRegisterInterestedDriver.
detach |
Detaches an IOService client from a provider in the I/O Registry.
public
virtual void detach( IOService *provider );
providerThe IOService object to detach from.
This function called in an IOService client removes the client as a child of the provider in the service plane of the I/O Registry. If the provider is not a parent of the client this is a no-op, otherwise the I/O Registry releases both the client and provider.
didTerminate |
Passes a termination up the stack.
public
virtual bool didTerminate( IOService *provider, IOOptionBits options, bool *defer );
providerThe terminated provider of this object.
optionsOptions originally passed to terminate.
deferIf there is pending I/O that requires this object to persist, and the provider is not opened by this object set defer to true and call the IOService::didTerminate() implementation when the I/O completes. Otherwise, leave defer set to its default value of false.
true.
Notification that a provider has been terminated, sent after recursing up the stack, in leaf-to-root order.
didYouWakeSystem |
Asks a driver if its device is the one that just woke the system from sleep.
public
virtual bool didYouWakeSystem ( void );
true if the driver's device did wake the system and false if it didn't.
Power management calls a power managed driver with this method to ask if its device is the one that just woke the system from sleep. If a device is capable of waking the system from sleep, its driver should implement didYouWakeSystem and return true if its device was responsible for waking the system.
disableInterrupt |
Synchronously disables a device interrupt.
public
virtual IOReturn disableInterrupt( int source);
sourceThe index of the interrupt source in the device.
An IOReturn code (kIOReturnNoInterrupt is returned if the source is not valid).
If the interrupt routine is running, the call will block until the routine completes. It is the caller's responsiblity to keep track of the enable state of the interrupt source.
enableInterrupt |
Enables a device interrupt.
public
virtual IOReturn enableInterrupt( int source);
sourceThe index of the interrupt source in the device.
An IOReturn code (kIOReturnNoInterrupt is returned if the source is not valid).
It is the caller's responsiblity to keep track of the enable state of the interrupt source.
errnoFromReturn |
Translates an IOReturn code to a BSD errno.
public
virtual int errnoFromReturn( IOReturn rtn );
rtnThe IOReturn code.
The BSD errno or EIO if unknown.
BSD defines its own return codes for its functions in sys/errno.h, and I/O Kit families may need to supply compliant results in BSD shims. Results are available for the standard return codes in IOReturn.h in IOService, while subclasses may implement this method to interpret family dependent return codes.
finalize |
Finalizes the destruction of an IOService object.
public
virtual bool finalize( IOOptionBits options );
optionsThe options passed to the terminate method of the IOService object are passed on to finalize.
true.
The finalize method is called in an inactive (ie. terminated) IOService object after the last client has detached. IOService's implementation will call stop, close, and detach on each provider. When finalize returns, the object's retain count will have no references generated by IOService's registration process.
free |
Frees data structures that were allocated when power management was initialized on this service.
public
virtual void free( void );
getAggressiveness |
Returns the current aggressiveness value for the given type.
public
virtual IOReturn getAggressiveness ( unsigned long type, unsigned long *currentLevel );
typeThe aggressiveness factor to query.
currentLevelUpon successful return, contains the value of aggressiveness factor type.
kIOReturnSuccess upon success; an I/O Kit error code otherwise.
getBusyState |
Returns the busyState of an IOService object.
public
virtual UInt32 getBusyState( void );
The busyState value.
Many activities in IOService are asynchronous. When registration, matching, or termination is in progress on an IOService object, its busyState is increased by one. Change in busyState to or from zero also changes the IOService object's provider's busyState by one, which means that an IOService object is marked busy when any of the above activities is ocurring on it or any of its clients.
getClient |
Returns an IOService object's primary client.
public
virtual IOService * getClient( void ) const;
The first client of the provider, or zero if the IOService object is not attached into the I/O Registry. The client is retained while it is attached, and should not be released by the caller.
This function called in an IOService provider will return the first client to attach to it. For IOService objects which have only only one client, this may be a useful simplification.
getClientIterator |
Returns an iterator over an IOService object's clients.
public
virtual OSIterator * getClientIterator( void ) const;
An iterator over the clients of the provider, or zero if there is a resource failure. The iterator must be released when the iteration is finished. All objects returned by the iteration are retained while the iterator is valid, though they may no longer be attached during the iteration.
For IOService objects that may have multiple clients, this method supplies an iterator over a provider's clients.
getDeviceMemory |
Returns the array of IODeviceMemory objects representing a device's memory mapped ranges.
public
virtual OSArray * getDeviceMemory( void );
An OSArray of IODeviceMemory objects, or zero if none are available. The array is retained by the provider, so is valid while attached.
This method returns an array of IODeviceMemory objects representing the physical memory ranges allocated to a memory mapped device.
getDeviceMemoryCount |
Returns a count of the physical memory ranges available for a device.
public
virtual IOItemCount getDeviceMemoryCount( void );
An integer count of the number of ranges available.
This method returns the count of physical memory ranges, each represented by an IODeviceMemory instance, that have been allocated for a memory mapped device.
getDeviceMemoryWithIndex |
Returns an instance of IODeviceMemory representing one of a device's memory mapped ranges.
public
virtual IODeviceMemory * getDeviceMemoryWithIndex( unsigned int index );
indexAn index into the array of ranges assigned to the device.
A pointer to an instance of IODeviceMemory, or zero if the index is beyond the count available. The IODeviceMemory is retained by the provider, so is valid while attached, or while any mappings to it exist. It should not be released by the caller. See also mapDeviceMemoryWithIndex, which creates a device memory mapping.
This method returns a pointer to an instance of IODeviceMemory for the physical memory range at the given index for a memory mapped device.
getInterruptType |
Returns the type of interrupt used for a device supplying hardware interrupts.
public
virtual IOReturn getInterruptType( int source, int *interruptType);
sourceThe index of the interrupt source in the device.
interruptTypeThe interrupt type for the interrupt source will be stored here by getInterruptType.kIOInterruptTypeEdge will be returned for edge-trigggered sources.kIOInterruptTypeLevel will be returned for level-trigggered sources.
An IOReturn code (kIOReturnNoInterrupt is returned if the source is not valid).
getMatchingServices |
Finds the set of current published IOService objects matching a matching dictionary.
public
static OSIterator * getMatchingServices( OSDictionary *matching );
matchingThe matching dictionary describing the desired IOService objects.
An instance of an iterator over a set of IOService objects. To be released by the caller.
Provides a method of finding the current set of published IOService objects matching the supplied matching dictionary.
getOpenClientIterator |
Returns an iterator over a provider's clients that currently have opened the provider.
public
virtual OSIterator * getOpenClientIterator( void ) const;
An iterator over the clients that have opened the provider, or zero if there is a resource failure. The iterator must be released when the iteration is finished. All objects returned by the iteration are retained while the iterator is valid, and the current entry in the iteration is locked with lockForArbitration, protecting it from state changes.
For IOService objects that may have multiple clients, this method supplies an iterator over a provider's clients, locking each in turn with lockForArbitration and returning those that have opened the provider.
getOpenProviderIterator |
Returns an iterator over an client's providers that are currently opened by the client.
public
virtual OSIterator * getOpenProviderIterator( void ) const;
An iterator over the providers the client has open, or zero if there is a resource failure. The iterator must be released when the iteration is finished. All objects returned by the iteration are retained while the iterator is valid, and the current entry in the iteration is locked with lockForArbitration, protecting it from state changes.
For those few IOService objects that obtain service from multiple providers, this method supplies an iterator over a client's providers, locking each in turn with lockForArbitration and returning those that have been opened by the client.
getPlatform |
Returns a pointer to the platform expert instance for the computer.
public
static IOPlatformExpert * getPlatform( void );
A pointer to the IOPlatformExport instance. It should not be released by the caller.
This method provides an accessor to the platform expert instance for the computer.
getPMRootDomain |
Returns a pointer to the power management root domain instance for the computer.
public
static class IOPMrootDomain * getPMRootDomain( void );
A pointer to the power management root domain instance. It should not be released by the caller.
This method provides an accessor to the power management root domain instance for the computer.
getPMworkloop |
Returns a pointer to the system-wide power management work loop.
public
virtual IOWorkLoop *getPMworkloop ( void );
Most drivers should create their own work loops to synchronize their code; drivers should not run arbitrary code on the power management work loop.
getPowerState |
Determines a device's power state.
public
UInt32 getPowerState();
The current power state's index into the device's power state array.
A device's "current power state" is updated at the end of each power state transition (e.g. transition from state 1 to state 0, or state 0 to state 2). This transition includes the time spent powering on or off any power plane children. Thus, if a child calls getPowerState on its power parent during system wake from sleep, the call will return the index to the device's off state rather than its on state.
getProvider |
Returns an IOService object's primary provider.
public
virtual IOService * getProvider( void ) const;
The first provider of the client, or zero if the IOService object is not attached into the I/O Registry. The provider is retained while the client is attached, and should not be released by the caller.
This function called in an IOService client will return the provider to which it was first attached. Because the majority of IOService objects have only one provider, this is a useful simplification and also supports caching of the provider when the I/O Registry is unchanged.
getProviderIterator |
Returns an iterator over an IOService object's providers.
public
virtual OSIterator * getProviderIterator( void ) const;
An iterator over the providers of the client, or zero if there is a resource failure. The iterator must be released when the iteration is finished. All objects returned by the iteration are retained while the iterator is valid, though they may no longer be attached during the iteration.
For those few IOService objects that obtain service from multiple providers, this method supplies an iterator over a client's providers.
getResources |
Allocates any needed resources for a published IOService object before clients attach.
public
virtual IOReturn getResources( void );
An IOReturn code; kIOReturnSuccess is necessary for the IOService object to be successfully used, otherwise the registration process for the object is halted.
This method is called during the registration process for an IOService object if there are successful driver matches, before any clients attach. It allows for lazy allocation of resources to an IOService object when a matching driver is found.
getResourceService |
Returns a pointer to the IOResources service.
public
static IOService * getResourceService( void );
A pointer to the IOResources instance. It should not be released by the caller.
IOService maintains a resource service IOResources that allows objects to be published and found globally in the I/O Kit based on a name, using the standard IOService matching and notification calls.
getServiceRoot |
Returns a pointer to the root of the service plane.
public
static IOService * getServiceRoot( void );
A pointer to the IOService instance at the root of the service plane. It should not be released by the caller.
This method provides an accessor to the root of the service plane for the computer.
getState |
Accessor for IOService state bits, not normally needed or used outside IOService.
public
virtual IOOptionBits getState( void ) const;
State bits for the IOService, eg. kIOServiceInactiveState, kIOServiceRegisteredState.
getWorkLoop |
Returns the current work loop or provider->getWorkLoop.
public
virtual IOWorkLoop * getWorkLoop() const;
A work loop, either the current work loop or it walks up the getProvider chain calling getWorkLoop. Eventually it will reach a valid work loop-based driver or the root of the I/O tree, where it will return a system-wide work loop. Returns 0 if it fails to find (or create) a work loop.
This function returns a valid work loop that a client can use to add an IOCommandGate to. The intention is that an IOService client has data that needs to be protected but doesn't want to pay the cost of a dedicated thread. This data has to be accessed from a provider's call-out context as well. So to achieve both of these goals the client creates an IOCommandGate to lock access to his data but he registers it with the provider's work loop, i.e. the work loop which will make the completion call-outs. This avoids a potential deadlock because the work loop gate uses a recursive lock, which allows the same lock to be held multiple times by a single thread.
handleClose |
Controls the open / close behavior of an IOService object (overrideable by subclasses).
public
virtual void handleClose( IOService *forClient, IOOptionBits options );
forClientDesignates the client of the provider requesting the close.
optionsOptions for the close, may be interpreted by the implementor of handleOpen.
IOService calls this method in its subclasses in response to the close method, so the subclass may implement the request. The default implementation provides single owner access to an IOService object via open. The object is locked via lockForArbitration before handleClose is called.
handleIsOpen |
Controls the open / close behavior of an IOService object (overrideable by subclasses).
public
virtual bool handleIsOpen( const IOService * forClient ) const;
forClientIf non-zero, isOpen returns the open state for that client. If zero is passed, isOpen returns the open state for all clients.
true if the specific, or any, client has the IOService object open.
IOService calls this method in its subclasses in response to the open method, so the subclass may implement the request. The default implementation provides single owner access to an IOService object via open. The object is locked via lockForArbitration before handleIsOpen is called.
handleOpen |
Controls the open / close behavior of an IOService object (overrideable by subclasses).
public
virtual bool handleOpen( IOService *forClient, IOOptionBits options, void *arg );
forClientDesignates the client of the provider requesting the open.
optionsOptions for the open, may be interpreted by the implementor of handleOpen.
trueif the open was successful; false otherwise.
IOService calls this method in its subclasses in response to the open method, so the subclass may implement the request. The default implementation provides single owner access to an IOService object via open. The object is locked via lockForArbitration before handleOpen is called.
initialPowerStateForDomainState |
Determines which power state a device is in, given the current power domain state.
public
virtual unsigned long initialPowerStateForDomainState ( IOPMPowerFlags domainState);
domainStateFlags that describe the character of "domain power"; they represent the outputPowerCharacter field of a state in the power domain's power state array.
A state number.
Power management calls this method once, when the driver is initializing power management.
Most drivers do not need to implement this method, and can rely upon the default IOService implementation. The IOService implementation scans the power state array looking for the highest state whose inputPowerRequirement field exactly matches the value of the domainState parameter. If more intelligent determination is required, the power managed driver should implement the method and override the superclass's implementation.
installNotification |
Adds a persistant notification handler to be notified of IOService events.
public
static IONotifier * installNotification( const OSSymbol * type, OSDictionary * matching, IOServiceNotificationHandler handler, void * target, void * ref, SInt32 priority, OSIterator ** existing );
typeSee addNotification.
matchingSee addNotification.
handlerSee addNotification.
selfSee addNotification.
refSee addNotification.
prioritySee addNotification.
existingReturns an iterator over the set of IOService objects that are currently in the specified state and match the matching dictionary.
See addNotification.
A lower level interface to addNotification that installs a handler and returns the current set of IOService objects that are in the specified state and match the matching dictionary.
isInactive |
Checks if the IOService object has been terminated, and is in the process of being destroyed.
public
bool isInactive( void ) const;
true if the IOService object has been terminated.
When an IOService object is successfully terminated, it is immediately made inactive, which blocks further attach()es, matching or notifications occuring on the object. It remains inactive until the last client closes, and is then finalized and destroyed.
isOpen |
Determines whether a specific, or any, client has an IOService object open.
public
virtual bool isOpen( const IOService * forClient = 0 ) const;
forClientIf non-zero,
Returns the open state of an IOService object with respect to the specified client, or when it is open by any client.
joinPMtree |
Joins the driver into the power plane of the I/O Registry .
public
virtual void joinPMtree ( IOService *driver );
driverThe driver to be added to the power plane, usually this.
A driver uses this method to call its nub when initializing (usually in its start routine after calling PMinit), to be attached into the power management hierarchy (i.e., the power plane). A driver usually calls this method on the driver for the device that provides it power (this is frequently the nub).
Before this call returns, the caller will probably be called at setPowerParent and setAggressiveness and possibly at addPowerChild as it is added to the hierarchy.
This method may be overridden by a nub subclass.
lockForArbitration |
Locks an IOService object against changes in state or ownership.
public
virtual bool lockForArbitration( bool isSuccessRequired = true );
isSuccessRequiredIf a request for access to an IOService object should be denied if it is terminated, pass false, otherwise pass true.
The registration, termination and open / close functions of IOService use lockForArbtration to single-thread access to an IOService object. lockForArbitration grants recursive access to the same thread.
makeUsable |
Requests that a device become usable.
public
virtual IOReturn makeUsable ( void );
A return code that can be ignored by the caller.
This method is called when some client of a device (or the device's own driver) is asking for the device to become usable. Power management responds by telling the object upon which this method is called to change to its highest power state.
makeUsable is implemented using changePowerStateToPriv.
Subsequent requests for lower power, such as from changePowerStateToPriv, will pre-empt this request.
mapDeviceMemoryWithIndex |
Maps a physical range of a device.
public
virtual IOMemoryMap * mapDeviceMemoryWithIndex( unsigned int index, IOOptionBits options = 0 );
indexAn index into the array of ranges assigned to the device.
An instance of IOMemoryMap, or zero if the index is beyond the count available. The mapping should be released only when access to it is no longer required.
This method creates a mapping for the IODeviceMemory at the given index, with IODeviceMemory::map(options). The mapping is represented by the returned instance of IOMemoryMap, which should not be released until the mapping is no longer required.
matchLocation |
Allows a registered IOService object to direct location matching.
public
virtual IOService * matchLocation( IOService *client );
clientThe IOService object at which matching is taking place.
Returns the IOService instance to be used for location matching.
By default, a location matching property will be applied to an IOService object's provider. This method allows that behavior to be overridden by families.
matchPropertyTable |
Allows a registered IOService object to implement family specific matching.
public
virtual bool matchPropertyTable( OSDictionary *table, SInt32 *score );
tableThe dictionary of properties to be matched against.
scorePointer to the current driver's probe score, which is used to order multiple matching drivers in the same match category. It defaults to the value of the IOProbeScore property in the drivers property table, or kIODefaultProbeScore if none is specified.
false if the family considers the matching dictionary does not match in properties it understands; true otherwise.
All matching on an IOService object will call this method to allow a family writer to implement matching in addition to the generic methods provided by IOService. The implementer should examine the matching dictionary passed to see if it contains properties the family understands for matching, and use them to match with the IOService object if so. Note that since matching is also carried out by other parts of the I/O Kit, the matching dictionary may contain properties the family does not understand - these should not be considered matching failures.
maxCapabilityForDomainState |
Determines a driver's highest power state possible for a given power domain state.
public
virtual unsigned long maxCapabilityForDomainState ( IOPMPowerFlags domainState );
domainStateFlags that describe the character of "domain power"; they represent the outputPowerCharacter field of a state in the power domain's power state array.
A state number.
This happens when the power domain is changing state and power management needs to determine which state the device is capable of in the new domain state.
Most drivers do not need to implement this method, and can rely upon the default IOService implementation. The IOService implementation scans the power state array looking for the highest state whose inputPowerRequirement field exactly matches the value of the domainState parameter. If more intelligent determination is required, the driver itself should implement the method and override the superclass's implementation.
message |
Receives a generic message delivered from an attached provider.
public
virtual IOReturn message( UInt32 type, IOService *provider, void *argument = 0 );
typeA type defined in IOMessage.h or defined by the provider family.
providerThe provider from which the message originates.
argumentAn argument defined by the provider family, not used by IOService.
An IOReturn code defined by the message type.
A provider may deliver messages via the message method to its clients informing them of state changes, such as kIOMessageServiceIsTerminated or kIOMessageServiceIsSuspended. Certain messages are defined by the I/O Kit in IOMessage.h while others may be family dependent. This method is implemented in the client to receive messages.
messageClient |
Sends a generic message to an attached client.
public
virtual IOReturn messageClient( UInt32 messageType, OSObject *client, void *messageArgument = 0, vm_size_t argSize = 0 );
typeA type defined in IOMessage.h or defined by the provider family.
clientA client of the IOService to send the message.
argumentAn argument defined by the provider family, not used by IOService.
The return code from the client message call.
A provider may deliver messages via the message method to its clients informing them of state changes, such as kIOMessageServiceIsTerminated or kIOMessageServiceIsSuspended. Certain messages are defined by the I/O Kit in IOMessage.h while others may be family dependent. This method may be called in the provider to send a message to the specified client, which may be useful for overrides.
messageClients |
Sends a generic message to all attached clients.
public
virtual IOReturn messageClients( UInt32 type, void *argument = 0, vm_size_t argSize = 0 );
typeA type defined in IOMessage.h or defined by the provider family.
argumentAn argument defined by the provider family, not used by IOService.
Any non-kIOReturnSuccess return codes returned by the clients, or kIOReturnSuccess if all return kIOReturnSuccess.
A provider may deliver messages via the message method to its clients informing them of state changes, such as kIOMessageServiceIsTerminated or kIOMessageServiceIsSuspended. Certain messages are defined by the I/O Kit in IOMessage.h while others may be family dependent. This method may be called in the provider to send a message to all the attached clients, via the messageClient method.
nameMatching(const char *, OSDictionary *) |
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService name match.
public
static OSDictionary * nameMatching( const char * name, OSDictionary * table = 0 );
nameThe service's name, as a const C string. Name matching is successful on IOService objects that respond successfully to the IORegistryEntry::compareName method.
tableIf zero, nameMatching creates a matching dictionary and returns a reference to it, otherwise the matching properties are added to the specified dictionary.
The matching dictionary created, or passed in, is returned on success, or zero on failure.
A very common matching criteria for IOService object is based on its name. nameMatching creates a matching dictionary that specifies any IOService object which responds successfully to the IORegistryEntry::compareName method. An existing dictionary may be passed in, in which case the matching properties will be added to that dictionary rather than creating a new one.
nameMatching(const OSString *, OSDictionary *) |
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService name match.
public
static OSDictionary * nameMatching( const OSString* name, OSDictionary * table = 0 );
nameThe service's name, as an OSString (which includes OSSymbol). Name matching is successful on IOService objects that respond successfully to the IORegistryEntry::compareName method.
tableIf zero, nameMatching creates a matching dictionary and returns a reference to it, otherwise the matching properties are added to the specified dictionary.
The matching dictionary created, or passed in, is returned on success, or zero on failure.
A very common matching criteria for IOService object is based on its name. nameMatching creates a matching dictionary that specifies any IOService object which responds successfully to the IORegistryEntry::compareName method. An existing dictionary may be passed in, in which case the matching properties will be added to that dictionary rather than creating a new one.
newTemperature |
(Deprecated. Do not use.) Tells a power managed driver that the temperature in the thermal zone has changed.
public
virtual IOReturn newTemperature ( long currentTemp, IOService *whichZone );
A thermal-zone driver calls a power managed driver with this method to tell it that the temperature in the zone has changed. This method is not intended to be overridden or called by drivers. This method is deprecated.
newUserClient |
Creates a connection for a non kernel client.
public
virtual IOReturn newUserClient( task_t owningTask, void *securityID, UInt32 type, OSDictionary *properties, IOUserClient **handler );
owningTaskThe Mach task of the client thread in the process of opening the user client. Note that in Mac OS X, each process is based on a Mach task and one or more Mach threads. For more information on the composition of a Mach task and its relationship with Mach threads, see "Tasks and Threads".
securityIDA token representing the access level for the task.
typeA constant specifying the type of connection to be created, specified by the caller of IOServiceOpen and interpreted only by the family.
handlerAn instance of an IOUserClient object to represent the connection, which will be released when the connection is closed, or zero if the connection was not opened.
propertiesA dictionary of additional properties for the connection.
A return code to be passed back to the caller of IOServiceOpen.
A non kernel client may request a connection be opened via the IOServiceOpen library function, which will call this method in an IOService object. The rules and capabilities of user level clients are family dependent, and use the functions of the IOUserClient class for support. IOService's implementation returns kIOReturnUnsupported, so any family supporting user clients must implement this method.
nextIdleTimeout |
Allows subclasses to customize idle power management behavior.
public
virtual SInt32 nextIdleTimeout( AbsoluteTime currentTime, AbsoluteTime lastActivity, unsigned int powerState);
currentTimeThe current time
lastActivityThe time of last activity on this device
powerStateThe device's current power state.
Returns the next time the device should idle off (in seconds, relative to the current time).
Returns the next time that the device should idle into its next lower power state. Subclasses may override for custom idle behavior.
A power managed driver might override this method to provide a more sophisticated idle power off algorithm than the one defined by power management.
open |
Requests active access to a provider.
public
virtual bool open( IOService *forClient, IOOptionBits options = 0, void *arg = 0 );
forClientDesignates the client of the provider requesting the open.
optionsOptions for the open. The provider family may implement options for open; IOService defines only kIOServiceSeize to request the device be withdrawn from its current owner.
true if the open was successful; false otherwise.
IOService provides generic open and close semantics to track clients of a provider that have established an active datapath. The use of open and close, and rules regarding ownership are family defined, and defined by the handleOpen and handleClose methods in the provider. Some families will limit access to a provider based on its open state.
PMinit |
Initializes power management for a driver.
public
virtual void PMinit ( void );
PMinit allocates and initializes the power management instance variables, and it should be called before accessing those variables or calling the power management methods. This method should be called inside the driver's start routine and must be paired with a call to PMstop.
Most calls to PMinit are followed by calls to joinPMtree and registerPowerDriver.
PMstop |
Frees and removes the driver from power management.
public
virtual void PMstop ( void );
The power managment variables don't exist after this call and the power managment methods in the caller shouldn't be called.
Calling PMstop cleans up for the three power management initialization calls: PMinit, joinPMtree, and registerPowerDriver.
powerChangeDone |
Tells a driver when a power change is complete.
protected
virtual void powerChangeDone ( unsigned long stateNumber);
stateNumberThe number of the state in the state array that the device has switched from.
Power management uses this method to call into a driver when a power change is completely done, when all interested parties have acknowledged the powerStateDidChangeTo call. The default implementation of this method is null; the method is meant to be overridden by subclassed power managed drivers. A driver should use this method to find out if a power change it initiated is complete.
powerDomainDidChangeTo |
Notifies a driver that its power domain is about to change state.
public
IOReturn powerDomainDidChangeTo ( IOPMPowerFlags newPowerStateFlags, IOPowerConnection *whichParent );
This call is handled internally by power management. It is not intended to be overridden or called by drivers.
powerDomainWillChangeTo |
Notifies a driver that its power domain is about to change state.
public
IOReturn powerDomainWillChangeTo ( IOPMPowerFlags newPowerStateFlags, IOPowerConnection *whichParent );
This call is handled internally by power management. It is not intended to be overridden or called by drivers.
powerOverrideOffPriv |
Allows a driver to disable a power override.
protected
IOReturn powerOverrideOffPriv ( void );
A return code that can be ignored by the caller.
When a driver has enabled an override via powerOverrideOnPriv, it can disable it again by calling this method in its superclass. Disabling the override reverts to the default algorithm for determining a device's power state. The superclass will now keep the device at the highest state required by changePowerStateTo, changePowerStateToPriv, and its children.
Turning off the override will initiate a power change if the driver's desired power state is different from the maximum of the power managed driver's desire and the children's desires.
powerOverrideOnPriv |
Allows a driver to ignore its children's power management requests and only use changePowerStateToPriv to define its own power state.
protected
IOReturn powerOverrideOnPriv ( void );
A return code that can be ignored by the caller.
Power management normally keeps a device at the highest state required by its requests via changePowerStateTo, changePowerStateToPriv, and its children. However, a driver may ensure a lower power state than otherwise required by itself and its children using powerOverrideOnPriv.
When the override is on, power management keeps the device's power state in the state specified by changePowerStateToPriv.
Turning on the override will initiate a power change if the driver's changePowerStateToPriv desired power state is different from the maximum of the changePowerStateTo desired power state and the children's desires.
powerStateDidChangeTo |
Informs interested parties that a device has changed to a different power state.
public
virtual IOReturn powerStateDidChangeTo ( IOPMPowerFlags capabilities, unsigned long stateNumber, IOService *whatDevice);
capabilitiesFlags that describe the capability of the device in the new power state (they come from the capabilityFlags field of the new state in the power state array).
stateNumberThe number of the state in the state array that the device is switching to.
whatDeviceA pointer to the driver that is changing. It can be used by a driver that is receiving power state change notifications for multiple devices to distinguish between them.
The driver returns IOPMAckImplied if it has prepared for the power change when it returns. If it has started preparing but not finished, it should return a number of microseconds which is an upper limit of the time it will need to finish preparing. Then, when it has completed its preparations, it should call acknowledgePowerChange.
Power management informs interested parties that a device has changed to a different power state. Interested parties are those that have registered for this notification via registerInterestedDriver. If you have called registerInterestedDriver on a power managed driver, you must implemnt powerStateWillChangeTo and powerStateDidChangeTo to receive the notifications.
powerStateDidChangeTo is called in a clean and separate thread context.
powerStateWillChangeTo is called before a power state transition takes place; powerStateDidChangeTo is called after the transition has completed.
powerStateForDomainState |
Determines what power state the device would be in for a given power domain state.
public
virtual unsigned long powerStateForDomainState ( IOPMPowerFlags domainState );
domainStateFlags that describe the character of "domain power"; they represent the outputPowerCharacter field of a state in the power domain's power state array.
A state number.
Power management calls a driver with this method to find out what power state the device would be in for a given power domain state. This happens when the power domain is changing state and power management needs to determine the effect of the change.
Most drivers do not need to implement this method, and can rely upon the default IOService implementation. The IOService implementation scans the power state array looking for the highest state whose inputPowerRequirement field exactly matches the value of the domainState parameter. If more intelligent determination is required, the power managed driver should implement the method and override the superclass's implementation.
powerStateWillChangeTo |
Informs interested parties that a device is about to change its power state.
public
virtual IOReturn powerStateWillChangeTo ( IOPMPowerFlags capabilities, unsigned long stateNumber, IOService *whatDevice);
capabilitiesFlags that describe the capability of the device in the new power state (they come from the capabilityFlags field of the new state in the power state array).
stateNumberThe number of the state in the state array that the device is switching to.
whatDeviceA pointer to the driver that is changing. It can be used by a driver that is receiving power state change notifications for multiple devices to distinguish between them.
The driver returns IOPMAckImplied if it has prepared for the power change when it returns. If it has started preparing but not finished, it should return a number of microseconds which is an upper limit of the time it will need to finish preparing. Then, when it has completed its preparations, it should call acknowledgePowerChange.
Power management informs interested parties that a device is about to change to a different power state. Interested parties are those that have registered for this notification via registerInterestedDriver. If you have called registerInterestedDriver on a power managed driver, you must implement powerStateWillChangeTo and powerStateDidChangeTo to receive the notifications.
powerStateWillChangeTo is called in a clean and separate thread context.
powerStateWillChangeTo is called before a power state transition takes place; powerStateDidChangeTo is called after the transition has completed.
probe |
During an IOService object's instantiation, probes a matched service to see if it can be used.
public
virtual IOService * probe( IOService *provider, SInt32 *score );
providerThe registered IOService object that matches a driver personality's matching dictionary.
scorePointer to the current driver's probe score, which is used to order multiple matching drivers in the same match category. It defaults to the value of the IOProbeScore property in the drivers property table, or kIODefaultProbeScore if none is specified. The probe method may alter the score to affect start order.
An IOService instance or zero when the probe is unsuccessful. In almost all cases the value of this is returned on success. If another IOService object is returned, the probed instance is detached and freed, and the returned instance is used in its stead for start.
The registration process for an IOService object (the provider) includes instantiating possible driver clients. The probe method is called in the client instance to check the matched service can be used before the driver is considered to be started. Since matching screens many possible providers, in many cases the probe method can be left unimplemented by IOService subclasses. The client is already attached to the provider when probe is called.
propertyMatching |
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService phandle match.
public
static OSDictionary * propertyMatching( const OSSymbol * key, const OSObject * value, OSDictionary * table = 0 );
keyThe service's phandle, as a const UInt32. PHandle matching is successful on IOService objects that respond successfully to the IORegistryEntry method compareName.
valueThe service's phandle, as a const UInt32. PHandle matching is successful on IOService's which respond successfully to the IORegistryEntry method compareName.
tableIf zero, nameMatching will create a matching dictionary and return a reference to it, otherwise the matching properties are added to the specified dictionary.
The matching dictionary created, or passed in, is returned on success, or zero on failure.
TODO A very common matching criteria for IOService is based on its name. nameMatching will create a matching dictionary that specifies any IOService which respond successfully to the IORegistryEntry method compareName. An existing dictionary may be passed in, in which case the matching properties will be added to that dictionary rather than creating a new one.
publishResource(const char *, OSObject *) |
Uses the resource service to publish a property.
public
static void publishResource( const char * key, OSObject * value = 0 );
keyA C string key that globally identifies the object.
Theobject to be published.
The resource service uses IOService object's matching and notification to allow objects to be published and found by any I/O Kit client by a global name. publishResource makes an object available to anyone waiting for it or looking for it in the future.
publishResource(const OSSymbol *, OSObject *) |
Uses the resource service to publish a property.
public
static void publishResource( const OSSymbol * key, OSObject * value = 0 );
keyAn OSSymbol key that globally identifies the object.
Theobject to be published.
The resource service uses IOService's matching and notification to allow objects to be published and found by any I/O Kit client by a global name. publishResource makes an object available to anyone waiting for it or looking for it in the future.
registerInterestedDriver |
Allows an IOService object to register interest in the changing power state of a power-managed IOService object.
public
virtual IOPMPowerFlags registerInterestedDriver ( IOService *theDriver );
theDriverThe driver of interest adds this pointer to the list of interested drivers. It informs drivers on this list before and after the power change.
Flags describing the capability of the device in its current power state. If the current power state is not yet defined, zero is returned (this is the case when the driver is not yet in the power domain hierarchy or hasn't fully registered with power management yet).
Call registerInterestedDriver on the IOService object you are interested in receiving power state messages from, and pass a pointer to the interested driver (this) as an argument.
The interested driver should override powerStateWillChangeTo and powerStateDidChangeTo to receive these power change messages.
Interested drivers must acknowledge power changes in powerStateWillChangeTo or powerStateDidChangeTo, either via return value or later calls to acknowledgePowerChange.
Most drivers do not need to override registerInterestedDriver.
registerInterrupt |
Registers a C function interrupt handler for a device supplying interrupts.
public
virtual IOReturn registerInterrupt( int source, OSObject *target, IOInterruptAction handler, void *refCon = 0);
sourceThe index of the interrupt source in the device.
targetAn object instance to be passed to the interrupt handler.
handlerThe C function to be called at primary interrupt time when the interrupt occurs. The handler should process the interrupt by clearing the interrupt, or by disabling the source.
refConA reference constant for the handler's use.
An IOReturn code.kIOReturnNoInterrupt is returned if the source is not valid; kIOReturnNoResources is returned if the interrupt already has an installed handler.
This method installs a C function interrupt handler to be called at primary interrupt time for a device's interrupt. Only one handler may be installed per interrupt source. IOInterruptEventSource provides a work loop based abstraction for interrupt delivery that may be more appropriate for work loop based drivers.
registerPowerDriver |
Registers a set of power states that the driver supports.
public
virtual IOReturn registerPowerDriver ( IOService *controllingDriver, IOPMPowerState *powerStates, unsigned long numberOfStates );
controllingDriverA pointer to the calling driver, usually this.
powerStatesA driver-defined array of power states that the driver and device support. Power states are defined in pwr_mgt/IOPMpowerState.h.
numberOfStatesThe number of power states in the array.
IOPMNoErr. All errors are logged via kprintf.
A driver defines its array of supported power states with power management in its power management initialization (its start routine). If successful, power management will call the driver to instruct it to change its power state through setPowerState.
Most drivers do not need to override registerPowerDriver. A nub may override registerPowerDriver if it needs to arrange its children in the power plane differently than the default placement, but this is uncommon.
registerService |
Starts the registration process for a newly discovered IOService object.
public
virtual void registerService( IOOptionBits options = 0 );
optionsThe default zero options mask is recommended and should be used in most cases. The registration process is usually asynchronous, with possible driver probing and notification occurring some time later. kIOServiceSynchronous may be passed to carry out the matching and notification process for currently registered clients before returning to the caller.
This function allows an IOService subclass to be published and made available to possible clients, by starting the registration process and delivering notifications to registered clients. The object should be completely setup and ready to field requests from clients before registerService is called.
removePowerChild |
Informs a power managed driver that one of its power plane childen is disappearing.
public
virtual IOReturn removePowerChild ( IOPowerConnection *theChild );
This call is handled internally by power management. It is not intended to be overridden or called by drivers.
requestPowerDomainState |
Tells a driver to adjust its power state.
public
virtual IOReturn requestPowerDomainState ( IOPMPowerFlags desiredState, IOPowerConnection *whichChild, unsigned long specificationFlags );
This call is handled internally by power management. It is not intended to be overridden or called by drivers.
requestProbe |
Requests that hardware be re-scanned for devices.
public
virtual IOReturn requestProbe( IOOptionBits options );
optionsFamily defined options, not interpreted by IOService.
An IOReturn code.
For bus families that do not usually detect device addition or removal, this method represents an external request (eg. from a utility application) to rescan and publish or remove found devices.
requestTerminate |
Passes a termination up the stack.
public
virtual bool requestTerminate( IOService *provider, IOOptionBits options );
providerThe terminated provider of this object.
optionsOptions originally passed to terminate, plus kIOServiceRecursing.
true if this object should be terminated now that its provider has been.
When an IOService is made inactive the default behavior is to also make any of its clients that have it as their only provider also inactive, in this way recursing the termination up the driver stack. This method allows an IOService object to override this behavior. Returning true from this method when passed a just terminated provider will cause the client to also be terminated.
resourceMatching(const char *, OSDictionary *) |
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify a resource service match.
public
static OSDictionary * resourceMatching( const char * name, OSDictionary * table = 0 );
nameThe resource name, as a const C string. Resource matching is successful when an object by that name has been published with the publishResource method.
tableIf zero, resourceMatching creates a matching dictionary and returns a reference to it, otherwise the matching properties are added to the specified dictionary.
The matching dictionary created, or passed in, is returned on success, or zero on failure.
IOService maintains a resource service IOResources that allows objects to be published and found globally in the I/O Kit based on a name, using the standard IOService matching and notification calls.
resourceMatching(const OSString *, OSDictionary *) |
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify a resource service match.
public
static OSDictionary * resourceMatching( const OSString * name, OSDictionary * table = 0 );
nameThe resource name, as an OSString (which includes OSSymbol). Resource matching is successful when an object by that name has been published with the publishResource method.
tableIf zero, resourceMatching creates a matching dictionary and returns a reference to it, otherwise the matching properties are added to the specified dictionary.
The matching dictionary created, or passed in, is returned on success, or zero on failure.
IOService maintains a resource service IOResources that allows objects to be published and found globally in the I/O Kit based on a name, using the standard IOService matching and notification calls.
serviceMatching(const char *, OSDictionary *) |
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService class match.
public
static OSDictionary * serviceMatching( const char * className, OSDictionary * table = 0 );
classNameThe class name, as a const C string. Class matching is successful on IOService objects of this class or any subclass.
tableIf zero, serviceMatching creates a matching dictionary and returns a reference to it, otherwise the matching properties are added to the specified dictionary.
The matching dictionary created, or passed in, is returned on success, or zero on failure.
A very common matching criteria for IOService object is based on its class. serviceMatching creates a matching dictionary that specifies any IOService object of a class, or its subclasses. The class is specified by name, and an existing dictionary may be passed in, in which case the matching properties will be added to that dictionary rather than creating a new one.
serviceMatching(const OSString *, OSDictionary *) |
Creates a matching dictionary, or adds matching properties to an existing dictionary, that specify an IOService class match.
public
static OSDictionary * serviceMatching( const OSString * className, OSDictionary * table = 0 );
classNameThe class name, as an OSString (which includes OSSymbol). Class matching is successful on IOService objects of this class or any subclass.
tableIf zero, serviceMatching creates a matching dictionary and returns a reference to it, otherwise the matching properties are added to the specified dictionary.
The matching dictionary created, or passed in, is returned on success, or zero on failure.
A very common matching criteria for IOService object is based on its class. serviceMatching creates a matching dictionary that specifies any IOService of a class, or its subclasses. The class is specified by name, and an existing dictionary may be passed in, in which case the matching properties will be added to that dictionary rather than creating a new one.
setAggressiveness |
Broadcasts an aggressiveness factor from the parent of a driver to the driver.
public
virtual IOReturn setAggressiveness ( unsigned long type, unsigned long newLevel );
typeThe aggressiveness factor type, such as kPMMinutesToDim, kPMMinutesToSpinDown, kPMMinutesToSleep, and kPMPowerSource. (Aggressiveness factors are defined in pwr_mgt/IOPM.h.)
newLevelThe aggressiveness factor's new value.
IOPMNoErr.
Implement setAggressiveness to receive a notification when an "aggressiveness Aggressiveness factors are a loose set of power management variables that contain values for system sleep timeout, display sleep timeout, whether the system is on battery or AC, and other power management features. There are several aggressiveness factors that can be broadcast and a driver may take action on whichever factors apply to it.
A driver that has joined the power plane via joinPMtree will receive setAgressiveness calls when aggressiveness factors change.
A driver may override this call if it needs to do something with the new factor (such as change its idle timeout). If overridden, the driver must call its superclass's setAgressiveness method in its own setAgressiveness implementation.
Most drivers do not need to implement setAgressiveness.
setDeviceMemory |
Sets the array of IODeviceMemory objects representing a device's memory mapped ranges.
public
virtual void setDeviceMemory( OSArray *array );
arrayAn OSArray of IODeviceMemory objects, or zero if none are available. The array will be retained by the object.
This method sets an array of IODeviceMemory objects representing the physical memory ranges allocated to a memory mapped device.
setIdleTimerPeriod |
Sets or changes the idle timer period.
public
virtual IOReturn setIdleTimerPeriod ( unsigned long );
periodThe desired idle timer period in seconds.
kIOReturnSuccess if successful. May return kIOReturnError if there was difficulty creating the timer event or the command queue.
A driver using the idleness determination provided by IOService calls its superclass with this method to set or change the idle timer period. See activityTickle for a description of this type of idleness determination.
setPowerParent |
For internal use only; deprecated; not intended to be called or overridden.
public
virtual IOReturn setPowerParent ( IOPowerConnection *theParent, bool stateKnown, IOPMPowerFlags currentState );
setPowerState |
Requests a power managed driver to change the power state of its device.
public
virtual IOReturn setPowerState ( unsigned long powerStateOrdinal, IOService *whatDevice );
powerStateOrdinalThe number in the power state array of the state the driver is being instructed to switch to.
whatDeviceA pointer to the power management object which registered to manage power for this device. In most cases, whatDevice will be equal to your driver's own this pointer.
The driver must return IOPMAckImplied if it has complied with the request when it returns. Otherwise if it has started the process of changing power state but not finished it, the driver should return a number of microseconds which is an upper limit of the time it will need to finish. Then, when it has completed the power switch, it should call acknowledgeSetPowerState.
A power managed driver must override setPowerState to take part in system power management. After a driver is registered with power management, the system uses setPowerState to power the device off and on for system sleep and wake.
Calls to PMinit and registerPowerDriver enable power management to change a device's power state using setPowerState.
setPowerState is called in a clean and separate thread context.
start |
During an IOService object's instantiation, starts the IOService object that has been selected to run on the provider.
public
virtual bool start( IOService *provider );
true if the start was successful; false otherwise (which will cause the instance to be detached and usually freed).
The start method of an IOService instance is called by its provider when it has been selected (due to its probe score and match category) as the winning client. The client is already attached to the provider when start is called.
Implementations of start must call start on their superclass at an appropriate point. If an implementation of start has already called super::start but subsequently determines that it will fail, it must call super::stop to balance the prior call to super::start and prevent reference leaks.
stop |
During an IOService termination, the stop method is called in its clients before they are detached & it is destroyed.
public
virtual void stop( IOService *provider );
The termination process for an IOService (the provider) will call stop in each of its clients, after they have closed the provider if they had it open, or immediately on termination.
stringFromReturn |
Supplies a programmer-friendly string from an IOReturn code.
public
virtual const char * stringFromReturn( IOReturn rtn );
rtnThe IOReturn code.
A pointer to a constant string, or zero if the return code is unknown.
Strings are available for the standard return codes in IOReturn.h in IOService, while subclasses may implement this method to interpret family dependent return codes.
systemWake |
Tells every driver in the power plane that the system is waking up.
public
virtual IOReturn systemWake ( void );
This call is handled internally by power management. It is not intended to be overridden or called by drivers.
systemWillShutdown |
Notifies members of the power plane of system shutdown and restart.
public
virtual void systemWillShutdown( IOOptionBits specifier );
specifierkIOMessageSystemWillPowerOff or kIOMessageSystemWillRestart.
This function is called for all members of the power plane in leaf-to-root order. If a subclass needs to wait for a pending I/O, then the call to systemWillShutdown should be postponed until the I/O completes.
Any power managed driver (which has called joinPMtree to join the power plane) interested in taking action at system shutdown or restart should override this method.
temperatureCriticalForZone |
Alerts a driver to a critical temperature in some thermal zone.
public
virtual IOReturn temperatureCriticalForZone ( IOService *whichZone );
This call is unused by power management. It is not intended to be called or overridden.
temporaryPowerClampOn |
A driver calls this method to hold itself in the highest power state until it has children.
public
virtual IOReturn temporaryPowerClampOn ( void );
A return code that can be ignored by the caller.
Use temporaryPowerClampOn to hold your driver in its highest power state while waiting for child devices to attach. After children have attached, the clamp is released and the device's power state is controlled by the children's requirements.
terminate |
Makes an IOService object inactive and begins its destruction.
public
virtual bool terminate( IOOptionBits options = 0 );
optionsIn most cases no options are needed. kIOServiceSynchronous may be passed to cause terminate to not return until the service is finalized.
Registering an IOService object informs possible clients of its existance and instantiates drivers that may be used with it; terminate involves the opposite process of informing clients that an IOService object is no longer able to be used and will be destroyed. By default, if any client has the service open, terminate fails. If the kIOServiceRequired flag is passed however, terminate will be successful though further progress in the destruction of the IOService object will not proceed until the last client has closed it. The service will be made inactive immediately upon successful termination, and all its clients will be notified via their message method with a message of type kIOMessageServiceIsTerminated. Both these actions take place on the caller's thread. After the IOService object is made inactive, further matching or attach calls will fail on it. Each client has its stop method called upon their close of an inactive IOService object , or on its termination if they do not have it open. After stop, detach is called in each client. When all clients have been detached, the finalize method is called in the inactive service. The termination process is inherently asynchronous because it will be deferred until all clients have chosen to close.
terminateClient |
Passes a termination up the stack.
public
virtual bool terminateClient( IOService *client, IOOptionBits options );
clientThe client of the terminated provider.
optionsOptions originally passed to terminate, plus kIOServiceRecursing.
result of the terminate request on the client.
When an IOService object is made inactive the default behavior is to also make any of its clients that have it as their only provider inactive, in this way recursing the termination up the driver stack. This method allows a terminated IOService object to override this behavior. Note the client may also override this behavior by overriding its terminate method.
unlockForArbitration |
Unlocks an IOService obkect after a successful lockForArbitration.
public
virtual void unlockForArbitration( void );
A thread granted exclusive access to an IOService object should release it with unlockForArbitration.
unregisterInterrupt |
Removes a C function interrupt handler for a device supplying hardware interrupts.
public
virtual IOReturn unregisterInterrupt( int source);
sourceThe index of the interrupt source in the device.
An IOReturn code (kIOReturnNoInterrupt is returned if the source is not valid).
This method removes a C function interrupt handler previously installed with registerInterrupt.
waitForService |
Waits for a matching to service to be published.
public
static IOService * waitForService( OSDictionary *matching, mach_timespec_t *timeout = 0);
matchingThe matching dictionary describing the desired IOService object. waitForService consumes one reference of the matching dictionary.
timeoutThe maximum time to wait.
A published IOService object matching the supplied dictionary.
Provides a method of waiting for an IOService object matching the supplied matching dictionary to be registered and fully matched.
waitQuiet |
Waits for an IOService object's busyState to be zero.
public
virtual IOReturn waitQuiet( mach_timespec_t *timeout = 0 );
timeoutSpecifies a maximum time to wait.
Returns an error code if Mach synchronization primitives fail, kIOReturnTimeout, or kIOReturnSuccess.
Blocks the caller until an IOService object is non busy.
willTerminate |
Passes a termination up the stack.
public
virtual bool willTerminate( IOService *provider, IOOptionBits options );
providerThe terminated provider of this object.
optionsOptions originally passed to terminate.
true.
Notification that a provider has been terminated, sent before recursing up the stack, in root-to-leaf order.
youAreRoot |
Informs the root power domain IOService object that is is the root power domain.
public
virtual IOReturn youAreRoot ( void );
The Platform Expert instantiates the root power domain IOService object and calls it with this method to inform it that it is the root power domain.
This call is handled internally by power management. It is not intended to be overridden or called by drivers.
ExpansionData |
protected
struct ExpansionData { };
This structure will be used to expand the capablilties of this class in the future.
reserved |
protected
ExpansionData * reserved;
Reserved for future use. (Internal use only)
|
Last Updated: 2008-12-19