iokit/IOKit/IOService.h

1368 /*! @function registerInterestedDriver
1370     @discussion Call <code>registerInterestedDriver</code> on the IOService object you are interested in receiving power state messages from, and pass a pointer to the interested driver (<code>this</code>) as an argument.
1378     IOPMPowerFlags registerInterestedDriver( IOService * theDriver );
1381     @abstract De-registers power state interest from a previous call to <code>registerInterestedDriver</code>.
1382     @discussion The retain from <code>registerInterestedDriver</code> is released. This method is synchronous against any <code>powerStateWillChangeTo</code> or <code>powerStateDidChangeTo</code> call targeting the interested driver, so when this method returns it is guaranteed those interest handlers will not be entered.
1384     @param theDriver The interested driver previously passed into @link registerInterestedDriver registerInterestedDriver@/link.
1393     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 @link registerInterestedDriver registerInterestedDriver@/link must call <code>acknowledgePowerChange</code>, or use an immediate acknowledgement return from <code>powerStateWillChangeTo</code> or <code>powerStateDidChangeTo</code>.
1645     @discussion 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 @link registerInterestedDriver registerInterestedDriver@/link. If you have called <code>registerInterestedDriver</code> on a power managed driver, you must implement <code>powerStateWillChangeTo</code> and @link powerStateDidChangeTo powerStateDidChangeTo@/link to receive the notifications.
1659     @discussion 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 @link registerInterestedDriver registerInterestedDriver@/link. If you have called <code>registerInterestedDriver</code> on a power managed driver, you must implemnt @link powerStateWillChangeTo powerStateWillChangeTo@/link and <code>powerStateDidChangeTo</code> to receive the notifications.