PerformDeviceConfigurationChange
Tells the device to handle a configuration change.
Declaration
virtual kern_return_t PerformDeviceConfigurationChange(uint64_t in_change_action, OSObject *in_change_info);Parameters
- in_change_action:
A
uint64_tthat indicates the action the device object takes. This is the same value previously passed toRequestDeviceConfigurationChange. This value is purely for the device’s usage; the host doesn’t look at this value. - in_change_info:
A pointer to an Osobject about the configuration change. This is the same value previously passed to
RequestDeviceConfigurationChange. This value is purely for the clock device’s usage; the host doesn’t look at this value. Retain and release this object reference as needed.
Return Value
kIOReturnSuccess on success, or another value if an error occurs. For a list of error codes, see Error Codes.
Discussion
The host calls this method to allow the clock device to perform a configuration change. This call can result from a call to RequestDeviceConfigurationChange or a from change to an I/O state that requires a configuration change.
Subclass and override this method to handle any custom configuration change requests, then call the superclass to update the I/O state. The framework stops I/O prior to performing the configuration change.