Contents

callPlatformFunction

Calls the platform function with the given name.

Declaration

virtual IOReturn callPlatformFunction(
 const OSSymbol *functionName, 
 bool waitForFunction, 
 void *param1,
 void *param2, 
 void *param3,
 void *param4 );

Parameters

  • functionName:

    Name 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.

  • waitForFunction:

    If true, callPlatformFunction will not return until the function has been called.

Return Value

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.

Overview

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.

See Also

Miscellaneous