Loading...
iokit/Kernel/IOStateReporter.cpp xnu-3789.41.3 xnu-11215.41.3
--- xnu/xnu-3789.41.3/iokit/Kernel/IOStateReporter.cpp
+++ xnu/xnu-11215.41.3/iokit/Kernel/IOStateReporter.cpp
@@ -1,8 +1,8 @@
 /*
  * Copyright (c) 2012-2013 Apple Computer, Inc.  All Rights Reserved.
- * 
+ *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- * 
+ *
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
@@ -11,10 +11,10 @@
  * unlawful or unlicensed copies of an Apple operating system, or to
  * circumvent, violate, or enable the circumvention or violation of, any
  * terms of an Apple operating system software license agreement.
- * 
+ *
  * Please obtain a copy of the License at
  * http://www.opensource.apple.com/apsl/ and read it before using this file.
- * 
+ *
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
@@ -22,10 +22,13 @@
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
- * 
+ *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 
+#define IOKIT_ENABLE_SHARED_PTR
+
+#include <libkern/c++/OSSharedPtr.h>
 #include <IOKit/IOKernelReportStructs.h>
 #include <IOKit/IOKernelReporters.h>
 #include "IOReporterDefs.h"
@@ -36,854 +39,853 @@
 
 
 /* static */
-IOStateReporter*
+OSSharedPtr<IOStateReporter>
 IOStateReporter::with(IOService *reportingService,
-                      IOReportCategories categories,
-                      int nstates,
-                      IOReportUnits unit/* = kIOReportUnitHWTicks*/)
-{
-    IOStateReporter *reporter, *rval = NULL;
-    
-    // kprintf("%s\n", __func__);      // can't IORLOG() from static
-    
-    reporter = new IOStateReporter;
-    if (!reporter)      goto finish;
-
-    if (!reporter->initWith(reportingService, categories, nstates, unit)) {
-        goto finish;
-    }
-    
-    // success
-    rval = reporter;
-    
-finish:
-    if (!rval) {
-        OSSafeReleaseNULL(reporter);
-    }
-    
-    return rval;
+    IOReportCategories categories,
+    int nstates,
+    IOReportUnit unit /* = kIOReportUnitHWTicks*/)
+{
+	OSSharedPtr<IOStateReporter> reporter;
+
+	if (nstates > INT16_MAX) {
+		return nullptr;
+	}
+
+	reporter = OSMakeShared<IOStateReporter>();
+	if (!reporter) {
+		return nullptr;
+	}
+
+	if (!reporter->initWith(reportingService, categories, (int16_t) nstates, unit)) {
+		return nullptr;
+	}
+
+	return reporter;
 }
 
 bool
 IOStateReporter::initWith(IOService *reportingService,
-                          IOReportCategories categories,
-                          int16_t nstates,
-                          IOReportUnits unit)
-{
-    bool success = false;
-    
-    IOReportChannelType channelType = {
-        .categories = categories,
-        .report_format = kIOReportFormatState,
-        .nelements = static_cast<uint16_t>(nstates),
-        .element_idx = 0
-    };
-    
-    if(super::init(reportingService, channelType, unit) != true) {
-        IORLOG("ERROR super::initWith failed");
-        success = false;
-        goto finish;
-    }
-    
-    _currentStates = NULL;
-    _lastUpdateTimes = NULL;
-    
-    success = true;
-    
-finish:    
-    return success;
+    IOReportCategories categories,
+    int16_t nstates,
+    IOReportUnit unit)
+{
+	bool success = false;
+
+	IOReportChannelType channelType = {
+		.categories = categories,
+		.report_format = kIOReportFormatState,
+		.nelements = static_cast<uint16_t>(nstates),
+		.element_idx = 0
+	};
+
+	if (super::init(reportingService, channelType, unit) != true) {
+		IORLOG("ERROR super::initWith failed");
+		success = false;
+		goto finish;
+	}
+
+	_currentStates = NULL;
+	_lastUpdateTimes = NULL;
+
+	success = true;
+
+finish:
+	return success;
 }
 
 
 void
 IOStateReporter::free(void)
 {
-    if (_currentStates) {
-        PREFL_MEMOP_PANIC(_nChannels, int);
-        IOFree(_currentStates, (size_t)_nChannels * sizeof(int));
-    }
-    if (_lastUpdateTimes) {
-        PREFL_MEMOP_PANIC(_nChannels, uint64_t);
-        IOFree(_lastUpdateTimes, (size_t)_nChannels * sizeof(uint64_t));
-    }
-    
-    super::free();
+	if (_currentStates) {
+		PREFL_MEMOP_PANIC(_nChannels, int);
+		IOFreeData(_currentStates, (size_t)_nChannels * sizeof(int));
+	}
+	if (_lastUpdateTimes) {
+		PREFL_MEMOP_PANIC(_nChannels, uint64_t);
+		IOFreeData(_lastUpdateTimes, (size_t)_nChannels * sizeof(uint64_t));
+	}
+
+	super::free();
 }
 
 
 IOReturn
 IOStateReporter::handleSwapPrepare(int newNChannels)
 {
-    IOReturn res = kIOReturnError;
-    size_t newCurStatesSize, newTSSize;
-    
-    //IORLOG("handleSwapPrepare (state) _nChannels before = %u", _nChannels);
-    
-    IOREPORTER_CHECK_CONFIG_LOCK();
-
-    if (_swapCurrentStates || _swapLastUpdateTimes) {
-        panic("IOStateReporter::_swap* already in use");
-    }
-    
-    // new currentStates buffer
-    PREFL_MEMOP_FAIL(newNChannels, int);
-    newCurStatesSize = (size_t)newNChannels * sizeof(int);
-    _swapCurrentStates = (int*)IOMalloc(newCurStatesSize);
-    if (_swapCurrentStates == NULL) {
-        res = kIOReturnNoMemory; goto finish;
-    }
-    memset(_swapCurrentStates, -1, newCurStatesSize);   // init w/"no state"
-    
-    // new timestamps buffer
-    PREFL_MEMOP_FAIL(newNChannels, uint64_t);
-    newTSSize = (size_t)newNChannels * sizeof(uint64_t);
-    _swapLastUpdateTimes = (uint64_t *)IOMalloc(newTSSize);
-    if (_swapLastUpdateTimes == NULL) {
-        res = kIOReturnNoMemory; goto finish;
-    }
-    memset(_swapLastUpdateTimes, 0, newTSSize);
-
-    res = super::handleSwapPrepare(newNChannels);
-    
-finish:
-    if (res) {
-        if (_swapCurrentStates) {
-            IOFree(_swapCurrentStates, newCurStatesSize);
-            _swapCurrentStates = NULL;
-        }
-        if (_swapLastUpdateTimes) {
-            IOFree(_swapLastUpdateTimes, newTSSize);
-            _swapLastUpdateTimes = NULL;
-        }
-    }
-
-    return res;
+	IOReturn res = kIOReturnError;
+	size_t newCurStatesSize, newTSSize;
+
+	//IORLOG("handleSwapPrepare (state) _nChannels before = %u", _nChannels);
+
+	IOREPORTER_CHECK_CONFIG_LOCK();
+
+	if (_swapCurrentStates || _swapLastUpdateTimes) {
+		panic("IOStateReporter::_swap* already in use");
+	}
+
+	// new currentStates buffer
+	PREFL_MEMOP_FAIL(newNChannels, int);
+	newCurStatesSize = (size_t)newNChannels * sizeof(int);
+	_swapCurrentStates = (int*)IOMallocData(newCurStatesSize);
+	if (_swapCurrentStates == NULL) {
+		res = kIOReturnNoMemory; goto finish;
+	}
+	memset(_swapCurrentStates, -1, newCurStatesSize); // init w/"no state"
+
+	// new timestamps buffer
+	PREFL_MEMOP_FAIL(newNChannels, uint64_t);
+	newTSSize = (size_t)newNChannels * sizeof(uint64_t);
+	_swapLastUpdateTimes = (uint64_t *)IOMallocZeroData(newTSSize);
+	if (_swapLastUpdateTimes == NULL) {
+		res = kIOReturnNoMemory; goto finish;
+	}
+
+	res = super::handleSwapPrepare(newNChannels);
+
+finish:
+	if (res) {
+		if (_swapCurrentStates) {
+			IOFreeData(_swapCurrentStates, newCurStatesSize);
+			_swapCurrentStates = NULL;
+		}
+		if (_swapLastUpdateTimes) {
+			IOFreeData(_swapLastUpdateTimes, newTSSize);
+			_swapLastUpdateTimes = NULL;
+		}
+	}
+
+	return res;
 }
 
 IOReturn
 IOStateReporter::handleAddChannelSwap(uint64_t channelID,
-                                      const OSSymbol *symChannelName)
-{
-    IOReturn res = kIOReturnError;
-    int cnt;
-    int *tmpCurStates;
-    uint64_t *tmpTimestamps;
-    bool swapComplete = false;
-    
-    //IORLOG("IOStateReporter::handleSwap");
-    
-    if (!_swapCurrentStates || !_swapLastUpdateTimes) {
-        IORLOG("IOReporter::handleSwap ERROR swap variables uninitialized!");
-        goto finish;
-    }
-    
-    IOREPORTER_CHECK_CONFIG_LOCK();
-    IOREPORTER_CHECK_LOCK();
-    
-    // Copy any existing buffers
-    if (_currentStates) {
-        PREFL_MEMOP_FAIL(_nChannels, int);
-        memcpy(_swapCurrentStates, _currentStates,
-               (size_t)_nChannels * sizeof(int));
-        
-        if (!_lastUpdateTimes) {
-            panic("IOStateReporter::handleAddChannelSwap _lastUpdateTimes unset despite non-NULL _currentStates");
-        }
-        PREFL_MEMOP_FAIL(_nChannels, uint64_t);
-        memcpy(_swapLastUpdateTimes, _lastUpdateTimes,
-               (size_t)_nChannels * sizeof(uint64_t));
-    }
-    
-    // Update principal instance variables, keep old values in _swap* for cleanup
-    tmpCurStates = _currentStates;
-    _currentStates = _swapCurrentStates;
-    _swapCurrentStates = tmpCurStates;
-
-    tmpTimestamps = _lastUpdateTimes;
-    _lastUpdateTimes = _swapLastUpdateTimes;
-    _swapLastUpdateTimes = tmpTimestamps;
-
-    swapComplete = true;
-    
-    // subclass success
-
-    // invoke superclass(es): base class updates _nChannels & _nElements
-    res = super::handleAddChannelSwap(channelID, symChannelName);
-    if (res) {
-        IORLOG("handleSwap(state) ERROR super::handleSwap failed!");
-        goto finish;
-    }
-    
-    // Channel added successfully, initialize the new channel's state_ids to 0..nStates-1
-    for (cnt = 0; cnt < _channelDimension; cnt++) {
-        handleSetStateID(channelID, cnt, (uint64_t)cnt);
-    }
-    
-finish:
-    if (res && swapComplete) {
-        // unswap so the unused buffers get cleaned up
-        tmpCurStates = _currentStates;
-        _currentStates = _swapCurrentStates;
-        _swapCurrentStates = tmpCurStates;
-
-        tmpTimestamps = _lastUpdateTimes;
-        _lastUpdateTimes = _swapLastUpdateTimes;
-        _swapLastUpdateTimes = tmpTimestamps;
-    }
-
-    return res;
+    const OSSymbol *symChannelName)
+{
+	IOReturn res = kIOReturnError;
+	int cnt;
+	int *tmpCurStates;
+	uint64_t *tmpTimestamps;
+	bool swapComplete = false;
+
+	//IORLOG("IOStateReporter::handleSwap");
+
+	if (!_swapCurrentStates || !_swapLastUpdateTimes) {
+		IORLOG("IOReporter::handleSwap ERROR swap variables uninitialized!");
+		goto finish;
+	}
+
+	IOREPORTER_CHECK_CONFIG_LOCK();
+	IOREPORTER_CHECK_LOCK();
+
+	// Copy any existing buffers
+	if (_currentStates) {
+		PREFL_MEMOP_FAIL(_nChannels, int);
+		memcpy(_swapCurrentStates, _currentStates,
+		    (size_t)_nChannels * sizeof(int));
+
+		if (!_lastUpdateTimes) {
+			panic("IOStateReporter::handleAddChannelSwap _lastUpdateTimes unset despite non-NULL _currentStates");
+		}
+		PREFL_MEMOP_FAIL(_nChannels, uint64_t);
+		memcpy(_swapLastUpdateTimes, _lastUpdateTimes,
+		    (size_t)_nChannels * sizeof(uint64_t));
+	}
+
+	// Update principal instance variables, keep old values in _swap* for cleanup
+	tmpCurStates = _currentStates;
+	_currentStates = _swapCurrentStates;
+	_swapCurrentStates = tmpCurStates;
+
+	tmpTimestamps = _lastUpdateTimes;
+	_lastUpdateTimes = _swapLastUpdateTimes;
+	_swapLastUpdateTimes = tmpTimestamps;
+
+	swapComplete = true;
+
+	// subclass success
+
+	// invoke superclass(es): base class updates _nChannels & _nElements
+	res = super::handleAddChannelSwap(channelID, symChannelName);
+	if (res) {
+		IORLOG("handleSwap(state) ERROR super::handleSwap failed!");
+		goto finish;
+	}
+
+	// Channel added successfully, initialize the new channel's state_ids to 0..nStates-1
+	for (cnt = 0; cnt < _channelDimension; cnt++) {
+		handleSetStateID(channelID, cnt, (uint64_t)cnt);
+	}
+
+finish:
+	if (res && swapComplete) {
+		// unswap so the unused buffers get cleaned up
+		tmpCurStates = _currentStates;
+		_currentStates = _swapCurrentStates;
+		_swapCurrentStates = tmpCurStates;
+
+		tmpTimestamps = _lastUpdateTimes;
+		_lastUpdateTimes = _swapLastUpdateTimes;
+		_swapLastUpdateTimes = tmpTimestamps;
+	}
+
+	return res;
 }
 
 
 void
 IOStateReporter::handleSwapCleanup(int swapNChannels)
 {
-    IOREPORTER_CHECK_CONFIG_LOCK();
-
-    super::handleSwapCleanup(swapNChannels);
-
-    if (_swapCurrentStates) {
-        PREFL_MEMOP_PANIC(swapNChannels, int);
-        IOFree(_swapCurrentStates, (size_t)swapNChannels * sizeof(int));
-        _swapCurrentStates = NULL;
-    }
-    if (_swapLastUpdateTimes) {
-        PREFL_MEMOP_PANIC(swapNChannels, uint64_t);
-        IOFree(_swapLastUpdateTimes, (size_t)swapNChannels * sizeof(uint64_t));
-        _swapLastUpdateTimes = NULL;
-    }
+	IOREPORTER_CHECK_CONFIG_LOCK();
+
+	super::handleSwapCleanup(swapNChannels);
+
+	if (_swapCurrentStates) {
+		PREFL_MEMOP_PANIC(swapNChannels, int);
+		IOFreeData(_swapCurrentStates, (size_t)swapNChannels * sizeof(int));
+		_swapCurrentStates = NULL;
+	}
+	if (_swapLastUpdateTimes) {
+		PREFL_MEMOP_PANIC(swapNChannels, uint64_t);
+		IOFreeData(_swapLastUpdateTimes, (size_t)swapNChannels * sizeof(uint64_t));
+		_swapLastUpdateTimes = NULL;
+	}
 }
 
 
 IOReturn
 IOStateReporter::_getStateIndices(uint64_t channel_id,
-                                  uint64_t state_id,
-                                  int *channel_index,
-                                  int *state_index)
-{
-    IOReturn res = kIOReturnError;
-    int cnt;
-    IOStateReportValues *values;
-    int element_index = 0;
-    
-    IOREPORTER_CHECK_LOCK();
-    
-    if (getChannelIndices(channel_id,
-                          channel_index,
-                          &element_index) != kIOReturnSuccess) {
-        res = kIOReturnBadArgument;
-
-        goto finish;
-    }
-    
-    for (cnt = 0; cnt < _channelDimension; cnt++) {
-        
-        values = (IOStateReportValues *)getElementValues(element_index + cnt);
-        
-        if (values == NULL) {
-
-            res = kIOReturnError;
-            goto finish;
-        }
-        
-        if (values->state_id == state_id) {
-            *state_index = cnt;
-            res = kIOReturnSuccess;
-            goto finish;
-        }
-    }
-    
-    res = kIOReturnBadArgument;
-    
-finish:
-    return res;
+    uint64_t state_id,
+    int *channel_index,
+    int *state_index)
+{
+	IOReturn res = kIOReturnError;
+	int cnt;
+	IOStateReportValues *values;
+	int element_index = 0;
+
+	IOREPORTER_CHECK_LOCK();
+
+	if (getChannelIndices(channel_id,
+	    channel_index,
+	    &element_index) != kIOReturnSuccess) {
+		res = kIOReturnBadArgument;
+
+		goto finish;
+	}
+
+	for (cnt = 0; cnt < _channelDimension; cnt++) {
+		values = (IOStateReportValues *)getElementValues(element_index + cnt);
+
+		if (values == NULL) {
+			res = kIOReturnError;
+			goto finish;
+		}
+
+		if (values->state_id == state_id) {
+			*state_index = cnt;
+			res = kIOReturnSuccess;
+			goto finish;
+		}
+	}
+
+	res = kIOReturnBadArgument;
+
+finish:
+	return res;
 }
 
 
 IOReturn
 IOStateReporter::setChannelState(uint64_t channel_id,
-                                 uint64_t new_state_id)
-{
-    IOReturn res = kIOReturnError;
-    int channel_index, new_state_index;
-    uint64_t last_intransition = 0;
-    uint64_t prev_state_residency = 0;
-    
-    lockReporter();
-    
-    if (_getStateIndices(channel_id, new_state_id, &channel_index, &new_state_index) == kIOReturnSuccess) {
-        res = handleSetStateByIndices(channel_index, new_state_index,
-                                      last_intransition,
-                                      prev_state_residency);
-        goto finish;
-    }
-    
-    res = kIOReturnBadArgument;
-    
-finish:
-    unlockReporter();
-    return res;
+    uint64_t new_state_id)
+{
+	IOReturn res = kIOReturnError;
+	int channel_index, new_state_index;
+	uint64_t last_intransition = 0;
+	uint64_t prev_state_residency = 0;
+
+	lockReporter();
+
+	if (_getStateIndices(channel_id, new_state_id, &channel_index, &new_state_index) == kIOReturnSuccess) {
+		res = handleSetStateByIndices(channel_index, new_state_index,
+		    last_intransition,
+		    prev_state_residency);
+		goto finish;
+	}
+
+	res = kIOReturnBadArgument;
+
+finish:
+	unlockReporter();
+	return res;
 }
 
 IOReturn
 IOStateReporter::setChannelState(uint64_t channel_id,
-                                 uint64_t new_state_id,
-                                 uint64_t last_intransition,
-                                 uint64_t prev_state_residency)
-{
-    return setChannelState(channel_id, new_state_id);
+    uint64_t new_state_id,
+    uint64_t last_intransition,
+    uint64_t prev_state_residency)
+{
+	return setChannelState(channel_id, new_state_id);
 }
 
 IOReturn
 IOStateReporter::overrideChannelState(uint64_t channel_id,
-                                      uint64_t state_id,
-                                      uint64_t time_in_state,
-                                      uint64_t intransitions,
-                                      uint64_t last_intransition /*=0*/)
-{
-    IOReturn res = kIOReturnError;
-    int channel_index, state_index;
-    
-    lockReporter();
-    
-    if (_getStateIndices(channel_id, state_id, &channel_index, &state_index) == kIOReturnSuccess) {
-        
-        if (_lastUpdateTimes[channel_index]) {
-            panic("overrideChannelState() cannot be used after setChannelState()!\n");
-        }
-        
-        res = handleOverrideChannelStateByIndices(channel_index, state_index,
-                                                  time_in_state, intransitions,
-                                                  last_intransition);
-        goto finish;
-    }
-    
-    res = kIOReturnBadArgument;
-    
-finish:
-    unlockReporter();
-    return res;
+    uint64_t state_id,
+    uint64_t time_in_state,
+    uint64_t intransitions,
+    uint64_t last_intransition /*=0*/)
+{
+	IOReturn res = kIOReturnError;
+	int channel_index, state_index;
+
+	lockReporter();
+
+	if (_getStateIndices(channel_id, state_id, &channel_index, &state_index) == kIOReturnSuccess) {
+		if (_lastUpdateTimes[channel_index]) {
+			panic("overrideChannelState() cannot be used after setChannelState()!");
+		}
+
+		res = handleOverrideChannelStateByIndices(channel_index, state_index,
+		    time_in_state, intransitions,
+		    last_intransition);
+		goto finish;
+	}
+
+	res = kIOReturnBadArgument;
+
+finish:
+	unlockReporter();
+	return res;
 }
 
 
 IOReturn
 IOStateReporter::handleOverrideChannelStateByIndices(int channel_index,
-                                             int state_index,
-                                             uint64_t time_in_state,
-                                             uint64_t intransitions,
-                                             uint64_t last_intransition /*=0*/)
-{
-    IOReturn kerr, result = kIOReturnError;
-    IOStateReportValues state_values;
-    int element_index;
-    
-    if (channel_index < 0 || channel_index >= _nChannels) {
-        result = kIOReturnBadArgument; goto finish;
-    }
-    
-    if (channel_index < 0 || channel_index > (_nElements - state_index)
-                                             / _channelDimension) {
-        result = kIOReturnOverrun; goto finish;
-    }
-    element_index = channel_index * _channelDimension + state_index;
-    
-    kerr = copyElementValues(element_index,(IOReportElementValues*)&state_values);
-    if (kerr) {
-        result = kerr; goto finish;
-    }
-    
-    // last_intransition = 0 -> no current state ("residency summary only")
-    state_values.last_intransition = last_intransition;
-    state_values.intransitions = intransitions;
-    state_values.upticks = time_in_state;
-    
-    // determines current time for metadata
-    kerr = setElementValues(element_index, (IOReportElementValues *)&state_values);
-    if (kerr) {
-        result = kerr; goto finish;
-    }
-    
-    // success
-    result = kIOReturnSuccess;
-    
-finish:
-    return result;
+    int state_index,
+    uint64_t time_in_state,
+    uint64_t intransitions,
+    uint64_t last_intransition /*=0*/)
+{
+	IOReturn kerr, result = kIOReturnError;
+	IOStateReportValues state_values;
+	int element_index;
+
+	if (channel_index < 0 || channel_index >= _nChannels) {
+		result = kIOReturnBadArgument; goto finish;
+	}
+
+	if (channel_index < 0 || channel_index > (_nElements - state_index)
+	    / _channelDimension) {
+		result = kIOReturnOverrun; goto finish;
+	}
+	element_index = channel_index * _channelDimension + state_index;
+
+	kerr = copyElementValues(element_index, (IOReportElementValues*)&state_values);
+	if (kerr) {
+		result = kerr; goto finish;
+	}
+
+	// last_intransition = 0 -> no current state ("residency summary only")
+	state_values.last_intransition = last_intransition;
+	state_values.intransitions = intransitions;
+	state_values.upticks = time_in_state;
+
+	// determines current time for metadata
+	kerr = setElementValues(element_index, (IOReportElementValues *)&state_values);
+	if (kerr) {
+		result = kerr; goto finish;
+	}
+
+	// success
+	result = kIOReturnSuccess;
+
+finish:
+	return result;
 }
 
 
 IOReturn
 IOStateReporter::incrementChannelState(uint64_t channel_id,
-                                       uint64_t state_id,
-                                       uint64_t time_in_state,
-                                       uint64_t intransitions,
-                                       uint64_t last_intransition /*=0*/)
-{
-    IOReturn res = kIOReturnError;
-    int channel_index, state_index;
-    
-    lockReporter();
-    
-    if (_getStateIndices(channel_id, state_id, &channel_index, &state_index) == kIOReturnSuccess) {
-        
-        if (_lastUpdateTimes[channel_index]) {
-            panic("incrementChannelState() cannot be used after setChannelState()!\n");
-        }
-        
-        res = handleIncrementChannelStateByIndices(channel_index, state_index,
-                                                   time_in_state, intransitions,
-                                                   last_intransition);
-        goto finish;
-    }
-    
-    res = kIOReturnBadArgument;
-    
-finish:
-    unlockReporter();
-    return res;
-
+    uint64_t state_id,
+    uint64_t time_in_state,
+    uint64_t intransitions,
+    uint64_t last_intransition /*=0*/)
+{
+	IOReturn res = kIOReturnError;
+	int channel_index, state_index;
+
+	lockReporter();
+
+	if (_getStateIndices(channel_id, state_id, &channel_index, &state_index) == kIOReturnSuccess) {
+		if (_lastUpdateTimes[channel_index]) {
+			panic("incrementChannelState() cannot be used after setChannelState()!");
+		}
+
+		res = handleIncrementChannelStateByIndices(channel_index, state_index,
+		    time_in_state, intransitions,
+		    last_intransition);
+		goto finish;
+	}
+
+	res = kIOReturnBadArgument;
+
+finish:
+	unlockReporter();
+	return res;
 }
 
 
 IOReturn
 IOStateReporter::handleIncrementChannelStateByIndices(int channel_index,
-                                                      int state_index,
-                                                      uint64_t time_in_state,
-                                                      uint64_t intransitions,
-                                                      uint64_t last_intransition /*=0*/)
-{
-    IOReturn kerr, result = kIOReturnError;
-    IOStateReportValues state_values;
-    int element_index;
-    
-    if (channel_index < 0 || channel_index >= _nChannels) {
-        result = kIOReturnBadArgument; goto finish;
-    }
-    
-    if (channel_index < 0 || channel_index > (_nElements - state_index)
-                                             / _channelDimension) {
-        result = kIOReturnOverrun; goto finish;
-    }
-    element_index = channel_index * _channelDimension + state_index;
-    
-    kerr = copyElementValues(element_index,(IOReportElementValues*)&state_values);
-    if (kerr) {
-        result = kerr;
-        goto finish;
-    }
-
-    state_values.last_intransition = last_intransition;
-    state_values.intransitions += intransitions;
-    state_values.upticks += time_in_state;
-    
-    // determines current time for metadata
-    kerr = setElementValues(element_index, (IOReportElementValues *)&state_values);
-    if (kerr) {
-        result = kerr;
-        goto finish;
-    }
-    
-    // success
-    result = kIOReturnSuccess;
-    
-finish:
-    return result;
+    int state_index,
+    uint64_t time_in_state,
+    uint64_t intransitions,
+    uint64_t last_intransition /*=0*/)
+{
+	IOReturn kerr, result = kIOReturnError;
+	IOStateReportValues state_values;
+	int element_index;
+
+	if (channel_index < 0 || channel_index >= _nChannels) {
+		result = kIOReturnBadArgument; goto finish;
+	}
+
+	if (channel_index < 0 || channel_index > (_nElements - state_index)
+	    / _channelDimension) {
+		result = kIOReturnOverrun; goto finish;
+	}
+	element_index = channel_index * _channelDimension + state_index;
+
+	kerr = copyElementValues(element_index, (IOReportElementValues*)&state_values);
+	if (kerr) {
+		result = kerr;
+		goto finish;
+	}
+
+	state_values.last_intransition = last_intransition;
+	state_values.intransitions += intransitions;
+	state_values.upticks += time_in_state;
+
+	// determines current time for metadata
+	kerr = setElementValues(element_index, (IOReportElementValues *)&state_values);
+	if (kerr) {
+		result = kerr;
+		goto finish;
+	}
+
+	// success
+	result = kIOReturnSuccess;
+
+finish:
+	return result;
 }
 
 
 IOReturn
 IOStateReporter::setState(uint64_t new_state_id)
 {
-    uint64_t last_intransition = 0;
-    uint64_t prev_state_residency = 0;
-    IOReturn res = kIOReturnError;
-    IOStateReportValues *values;
-    int channel_index = 0, element_index = 0, new_state_index = 0;
-    int cnt;
-    
-    lockReporter();
-    
-    if (_nChannels == 1) {
-
-        for (cnt = 0; cnt < _channelDimension; cnt++) {
-            
-            new_state_index = element_index + cnt;
-            
-            values = (IOStateReportValues *)getElementValues(new_state_index);
-            
-            if (values == NULL) {
-                res = kIOReturnError;
-                goto finish;
-            }
-                        
-            if (values->state_id == new_state_id) {
-                
-                res = handleSetStateByIndices(channel_index, new_state_index,
-                                              last_intransition,
-                                              prev_state_residency);
-                goto finish;
-            }
-        }
-    }
-    
-    res = kIOReturnBadArgument;
-
-finish:
-    unlockReporter();
-    return res;
+	uint64_t last_intransition = 0;
+	uint64_t prev_state_residency = 0;
+	IOReturn res = kIOReturnError;
+	IOStateReportValues *values;
+	int channel_index = 0, element_index = 0, new_state_index = 0;
+	int cnt;
+
+	lockReporter();
+
+	if (_nChannels == 1) {
+		for (cnt = 0; cnt < _channelDimension; cnt++) {
+			new_state_index = element_index + cnt;
+
+			values = (IOStateReportValues *)getElementValues(new_state_index);
+
+			if (values == NULL) {
+				res = kIOReturnError;
+				goto finish;
+			}
+
+			if (values->state_id == new_state_id) {
+				res = handleSetStateByIndices(channel_index, new_state_index,
+				    last_intransition,
+				    prev_state_residency);
+				goto finish;
+			}
+		}
+	}
+
+	res = kIOReturnBadArgument;
+
+finish:
+	unlockReporter();
+	return res;
 }
 
 IOReturn
 IOStateReporter::setState(uint64_t new_state_id,
-                          uint64_t last_intransition,
-                          uint64_t prev_state_residency)
-{
-    return setState(new_state_id);
+    uint64_t last_intransition,
+    uint64_t prev_state_residency)
+{
+	return setState(new_state_id);
 }
 
 IOReturn
 IOStateReporter::setStateID(uint64_t channel_id,
-                            int state_index,
-                            uint64_t state_id)
-{
-    IOReturn res = kIOReturnError;
-    
-    lockReporter();
-    
-    res = handleSetStateID(channel_id, state_index, state_id);
-    
-    unlockReporter();
-    
-    return res;    
+    int state_index,
+    uint64_t state_id)
+{
+	IOReturn res = kIOReturnError;
+
+	lockReporter();
+
+	res = handleSetStateID(channel_id, state_index, state_id);
+
+	unlockReporter();
+
+	return res;
 }
 
 
 IOReturn
 IOStateReporter::handleSetStateID(uint64_t channel_id,
-                                  int state_index,
-                                  uint64_t state_id)
-{
-    IOReturn res = kIOReturnError;
-    IOStateReportValues state_values;
-    int element_index = 0;
-    
-    IOREPORTER_CHECK_LOCK();
-    
-    if (getFirstElementIndex(channel_id, &element_index) == kIOReturnSuccess) {
-        
-        if (state_index >= _channelDimension) {
-            res = kIOReturnBadArgument; goto finish;
-        }
-        if (_nElements - state_index <= element_index) {
-            res = kIOReturnOverrun; goto finish;
-        }
-        element_index += state_index;
-        
-        if (copyElementValues(element_index, (IOReportElementValues *)&state_values) != kIOReturnSuccess) {
-            res = kIOReturnBadArgument;
-            goto finish;
-        }
-        
-        state_values.state_id = state_id;
-        
-        res = setElementValues(element_index, (IOReportElementValues *)&state_values);
-    }
-    
-    // FIXME: set a bit somewhere (reporter-wide?) that state_ids can no longer be
-    // assumed to be contiguous
-finish:
-    return res;
+    int state_index,
+    uint64_t state_id)
+{
+	IOReturn res = kIOReturnError;
+	IOStateReportValues state_values;
+	int element_index = 0;
+
+	IOREPORTER_CHECK_LOCK();
+
+	if (getFirstElementIndex(channel_id, &element_index) == kIOReturnSuccess) {
+		if (state_index >= _channelDimension) {
+			res = kIOReturnBadArgument; goto finish;
+		}
+		if (_nElements - state_index <= element_index) {
+			res = kIOReturnOverrun; goto finish;
+		}
+		element_index += state_index;
+
+		if (copyElementValues(element_index, (IOReportElementValues *)&state_values) != kIOReturnSuccess) {
+			res = kIOReturnBadArgument;
+			goto finish;
+		}
+
+		state_values.state_id = state_id;
+
+		res = setElementValues(element_index, (IOReportElementValues *)&state_values);
+	}
+
+	// FIXME: set a bit somewhere (reporter-wide?) that state_ids can no longer be
+	// assumed to be contiguous
+finish:
+	return res;
 }
 
 IOReturn
 IOStateReporter::setStateByIndices(int channel_index,
-                                   int new_state_index)
-{
-    IOReturn res = kIOReturnError;
-    uint64_t last_intransition = 0;
-    uint64_t prev_state_residency = 0;
-    
-    lockReporter();
-    
-    res = handleSetStateByIndices(channel_index, new_state_index,
-                                  last_intransition, prev_state_residency);
-    
-    unlockReporter();
-    
-    return res;
+    int new_state_index)
+{
+	IOReturn res = kIOReturnError;
+	uint64_t last_intransition = 0;
+	uint64_t prev_state_residency = 0;
+
+	lockReporter();
+
+	res = handleSetStateByIndices(channel_index, new_state_index,
+	    last_intransition, prev_state_residency);
+
+	unlockReporter();
+
+	return res;
 }
 
 IOReturn
 IOStateReporter::setStateByIndices(int channel_index,
-                                   int new_state_index,
-                                   uint64_t last_intransition,
-                                   uint64_t prev_state_residency)
-{
-    return setStateByIndices(channel_index, new_state_index);
+    int new_state_index,
+    uint64_t last_intransition,
+    uint64_t prev_state_residency)
+{
+	return setStateByIndices(channel_index, new_state_index);
 }
 
 IOReturn
 IOStateReporter::handleSetStateByIndices(int channel_index,
-                                         int new_state_index,
-                                         uint64_t last_intransition,
-                                         uint64_t prev_state_residency)
-{
-    IOReturn res = kIOReturnError;
-    
-    IOStateReportValues curr_state_values, new_state_values;
-    int curr_state_index = 0;
-    int curr_element_index, new_element_index;
-    uint64_t last_ch_update_time = 0;
-    uint64_t recordTime = mach_absolute_time();
-    
-    IOREPORTER_CHECK_LOCK();
-    
-    if (channel_index < 0 || channel_index >= _nChannels) {
-        res = kIOReturnBadArgument; goto finish;
-    }
-    
-    // if no timestamp provided, last_intransition = time of recording (now)
-    if (last_intransition == 0) {
-        last_intransition = recordTime;
-    }
-
-    // First update target state if different than the current state
-    // _currentStates[] initialized to -1 to detect first state transition
-    curr_state_index = _currentStates[channel_index];
-    if (new_state_index != curr_state_index) {
-        // fetch element data
-        if (channel_index < 0 || channel_index > (_nElements-new_state_index)
-                                                 / _channelDimension) {
-            res = kIOReturnOverrun; goto finish;
-        }
-        new_element_index = channel_index*_channelDimension + new_state_index;
-        if (copyElementValues(new_element_index,
-                              (IOReportElementValues *)&new_state_values)) {
-            res = kIOReturnBadArgument;
-            goto finish;
-        }
-    
-        // Update new state's transition info
-        new_state_values.intransitions += 1;
-        new_state_values.last_intransition = last_intransition;
-
-        // and store the values
-        res = setElementValues(new_element_index,
-                               (IOReportElementValues *)&new_state_values,
-                               recordTime);
-
-        if (res != kIOReturnSuccess) {
-            goto finish;
-        }
-        
-        _currentStates[channel_index] = new_state_index;
-    }
-    
-    /* Now update time spent in any previous state
-       If new_state_index = curr_state_index, this updates time in the
-       current state.  If this is the channel's first state transition,
-       the last update time will be zero.
-
-       Note: While setState() should never be called on a channel being
-       updated with increment/overrideChannelState(), that's another way
-       that the last update time might not exist.  Regardless, if there
-       is no basis for determining time spent in previous state, there's
-       nothing to update!
-     */
-    last_ch_update_time = _lastUpdateTimes[channel_index];
-    if (last_ch_update_time != 0) {
-        if (channel_index < 0 || channel_index > (_nElements-curr_state_index)
-                                                 / _channelDimension) {
-            res = kIOReturnOverrun; goto finish;
-        }
-        curr_element_index = channel_index*_channelDimension + curr_state_index;
-        if (copyElementValues(curr_element_index,
-                              (IOReportElementValues *)&curr_state_values)) {
-            res = kIOReturnBadArgument;
-            goto finish;
-        }
-        // compute the time spent in previous state, unless provided
-        if (prev_state_residency == 0) {
-            prev_state_residency = last_intransition - last_ch_update_time;
-        }
-        
-        curr_state_values.upticks += prev_state_residency;
-        
-        res = setElementValues(curr_element_index,
-                               (IOReportElementValues*)&curr_state_values,
-                               recordTime);
-        
-        if (res != kIOReturnSuccess) {
-            goto finish;
-        }
-    }
-    
-    // record basis for next "time in prior state" calculation
-    // (also arms a panic in override/incrementChannelState())
-    _lastUpdateTimes[channel_index] = last_intransition;
-    
-finish:
-    return res;
+    int new_state_index,
+    uint64_t last_intransition,
+    uint64_t prev_state_residency)
+{
+	IOReturn res = kIOReturnError;
+
+	IOStateReportValues curr_state_values, new_state_values;
+	int curr_state_index = 0;
+	int curr_element_index, new_element_index;
+	uint64_t last_ch_update_time = 0;
+	uint64_t recordTime = mach_absolute_time();
+
+	IOREPORTER_CHECK_LOCK();
+
+	if (channel_index < 0 || channel_index >= _nChannels) {
+		res = kIOReturnBadArgument; goto finish;
+	}
+
+	// if no timestamp provided, last_intransition = time of recording (now)
+	if (last_intransition == 0) {
+		last_intransition = recordTime;
+	}
+
+	// First update target state if different than the current state
+	// _currentStates[] initialized to -1 to detect first state transition
+	curr_state_index = _currentStates[channel_index];
+	if (new_state_index != curr_state_index) {
+		// fetch element data
+		if (channel_index < 0 || channel_index > (_nElements - new_state_index)
+		    / _channelDimension) {
+			res = kIOReturnOverrun; goto finish;
+		}
+		new_element_index = channel_index * _channelDimension + new_state_index;
+		if (copyElementValues(new_element_index,
+		    (IOReportElementValues *)&new_state_values)) {
+			res = kIOReturnBadArgument;
+			goto finish;
+		}
+
+		// Update new state's transition info
+		new_state_values.intransitions += 1;
+		new_state_values.last_intransition = last_intransition;
+
+		// and store the values
+		res = setElementValues(new_element_index,
+		    (IOReportElementValues *)&new_state_values,
+		    recordTime);
+
+		if (res != kIOReturnSuccess) {
+			goto finish;
+		}
+
+		_currentStates[channel_index] = new_state_index;
+	}
+
+	/* Now update time spent in any previous state
+	 *  If new_state_index = curr_state_index, this updates time in the
+	 *  current state.  If this is the channel's first state transition,
+	 *  the last update time will be zero.
+	 *
+	 *  Note: While setState() should never be called on a channel being
+	 *  updated with increment/overrideChannelState(), that's another way
+	 *  that the last update time might not exist.  Regardless, if there
+	 *  is no basis for determining time spent in previous state, there's
+	 *  nothing to update!
+	 */
+	last_ch_update_time = _lastUpdateTimes[channel_index];
+	if (last_ch_update_time != 0) {
+		if (channel_index < 0 || channel_index > (_nElements - curr_state_index)
+		    / _channelDimension) {
+			res = kIOReturnOverrun; goto finish;
+		}
+		curr_element_index = channel_index * _channelDimension + curr_state_index;
+		if (copyElementValues(curr_element_index,
+		    (IOReportElementValues *)&curr_state_values)) {
+			res = kIOReturnBadArgument;
+			goto finish;
+		}
+		// compute the time spent in previous state, unless provided
+		if (prev_state_residency == 0) {
+			prev_state_residency = last_intransition - last_ch_update_time;
+		}
+
+		curr_state_values.upticks += prev_state_residency;
+
+		res = setElementValues(curr_element_index,
+		    (IOReportElementValues*)&curr_state_values,
+		    recordTime);
+
+		if (res != kIOReturnSuccess) {
+			goto finish;
+		}
+	}
+
+	// record basis for next "time in prior state" calculation
+	// (also arms a panic in override/incrementChannelState())
+	_lastUpdateTimes[channel_index] = last_intransition;
+
+finish:
+	return res;
 }
 
 
 // blocks might make this slightly easier?
 uint64_t
 IOStateReporter::getStateInTransitions(uint64_t channel_id,
-                                       uint64_t state_id)
-{
-    return _getStateValue(channel_id, state_id, kInTransitions);
+    uint64_t state_id)
+{
+	return _getStateValue(channel_id, state_id, kInTransitions);
 }
 
 uint64_t
 IOStateReporter::getStateResidencyTime(uint64_t channel_id,
-                                       uint64_t state_id)
-{
-    return _getStateValue(channel_id, state_id, kResidencyTime);
+    uint64_t state_id)
+{
+	return _getStateValue(channel_id, state_id, kResidencyTime);
 }
 
 uint64_t
 IOStateReporter::getStateLastTransitionTime(uint64_t channel_id,
-                                            uint64_t state_id)
-{
-    return _getStateValue(channel_id, state_id, kLastTransitionTime);
+    uint64_t state_id)
+{
+	return _getStateValue(channel_id, state_id, kLastTransitionTime);
 }
 
 uint64_t
 IOStateReporter::_getStateValue(uint64_t channel_id,
-                                uint64_t state_id,
-                                enum valueSelector value)
-{
-    int channel_index = 0, element_index = 0, cnt;
-    IOStateReportValues *values = NULL;
-    uint64_t result = kIOReportInvalidValue;
-    
-    lockReporter();
-    
-    if (getChannelIndices(channel_id, &channel_index, &element_index) == kIOReturnSuccess) {
-        
-        if (updateChannelValues(channel_index) == kIOReturnSuccess) {
-        
-            for (cnt = 0; cnt < _channelDimension; cnt++) {
-                
-                values = (IOStateReportValues *)getElementValues(element_index);
-                
-                if (state_id == values->state_id) {
-                    
-                    switch (value) {
-                        case kInTransitions:
-                            result = values->intransitions;
-                            break;
-                        case kResidencyTime:
-                            result = values->upticks;
-                            break;
-                        case kLastTransitionTime:
-                            result = values->last_intransition;
-                            break;
-                        default:
-                            break;
-                    }
-                    
-                    break;
-                }
-                
-                element_index++;
-            }
-        }
-    }
-
-    unlockReporter();
-    return result;
+    uint64_t state_id,
+    enum valueSelector value)
+{
+	int channel_index = 0, element_index = 0, cnt;
+	IOStateReportValues *values = NULL;
+	uint64_t result = kIOReportInvalidValue;
+
+	lockReporter();
+
+	if (getChannelIndices(channel_id, &channel_index, &element_index) == kIOReturnSuccess) {
+		if (updateChannelValues(channel_index) == kIOReturnSuccess) {
+			for (cnt = 0; cnt < _channelDimension; cnt++) {
+				values = (IOStateReportValues *)getElementValues(element_index);
+
+				if (state_id == values->state_id) {
+					switch (value) {
+					case kInTransitions:
+						result = values->intransitions;
+						break;
+					case kResidencyTime:
+						result = values->upticks;
+						break;
+					case kLastTransitionTime:
+						result = values->last_intransition;
+						break;
+					default:
+						break;
+					}
+
+					break;
+				}
+
+				element_index++;
+			}
+		}
+	}
+
+	unlockReporter();
+	return result;
 }
 
 
 uint64_t
 IOStateReporter::getStateLastChannelUpdateTime(uint64_t channel_id)
 {
-    int channel_index;
-    uint64_t result = kIOReportInvalidValue;
-    
-    lockReporter();
-    
-    if (getChannelIndex(channel_id, &channel_index) == kIOReturnSuccess) {
-        
-        result = _lastUpdateTimes[channel_index];
-    }
-    
-    unlockReporter();
-        
-    return result;
+	int channel_index;
+	uint64_t result = kIOReportInvalidValue;
+
+	lockReporter();
+
+	if (getChannelIndex(channel_id, &channel_index) == kIOReturnSuccess) {
+		result = _lastUpdateTimes[channel_index];
+	}
+
+	unlockReporter();
+
+	return result;
 }
 
 
 /* updateChannelValues() is called to refresh state before being
-   reported outside the reporter.  In the case of IOStateReporter,
-   this is primarily an update to the "time in state" data.
-*/
+ *  reported outside the reporter.  In the case of IOStateReporter,
+ *  this is primarily an update to the "time in state" data.
+ */
 IOReturn
 IOStateReporter::updateChannelValues(int channel_index)
 {
-    IOReturn kerr, result = kIOReturnError;
-    
-    int state_index, element_idx;
-    uint64_t currentTime;
-    uint64_t last_ch_update_time;
-    uint64_t time_in_state;
-    IOStateReportValues state_values;
-    
-    IOREPORTER_CHECK_LOCK();
-
-    if (channel_index < 0 || channel_index >= _nChannels) {
-        result = kIOReturnBadArgument; goto finish;
-    }
-    
-    /* First check to see whether this channel has begun self-
-       calculation of time in state.  It's possible this channel
-       has yet to be initialized or that the driver is updating
-       the channel with override/incrementChannelState() which
-       never enable automatic time-in-state updates.  In that case,
-       there is nothing to update and we return success.
-     */
-    last_ch_update_time = _lastUpdateTimes[channel_index];
-    if (last_ch_update_time == 0) {
-        result = kIOReturnSuccess; goto finish;
-    }
-
-    // figure out the current state (if any)
-    state_index = _currentStates[channel_index];
-    
-    // e.g. given 4 4-state channels, the boundary is ch[3].st[3] <- _elems[15]
-    if (channel_index < 0 || channel_index > (_nElements - state_index)
-                                             / _channelDimension) {
-        result = kIOReturnOverrun; goto finish;
-    }
-    element_idx = channel_index * _channelDimension + state_index;
-    
-    // get the current values
-    kerr = copyElementValues(element_idx,(IOReportElementValues*)&state_values);
-    if (kerr) {
-        result = kerr; goto finish;
-    }
-
-    // calculate time in state
-    currentTime = mach_absolute_time();
-    time_in_state = currentTime - last_ch_update_time;
-    state_values.upticks += time_in_state;
-    
-    // and store the values
-    kerr = setElementValues(element_idx,
-                            (IOReportElementValues *)&state_values,
-                            currentTime);
-    if (kerr) {
-        result = kerr; goto finish;
-    }
-    
-    // Record basis for next "prior time" calculation
-    _lastUpdateTimes[channel_index] = currentTime;
-
-
-    // success
-    result = kIOReturnSuccess;
-    
-finish:
-    return result;
-}
+	IOReturn kerr, result = kIOReturnError;
+
+	int state_index, element_idx;
+	uint64_t currentTime;
+	uint64_t last_ch_update_time;
+	uint64_t time_in_state;
+	IOStateReportValues state_values;
+
+	IOREPORTER_CHECK_LOCK();
+
+	if (channel_index < 0 || channel_index >= _nChannels) {
+		result = kIOReturnBadArgument; goto finish;
+	}
+
+	/* First check to see whether this channel has begun self-
+	 *  calculation of time in state.  It's possible this channel
+	 *  has yet to be initialized or that the driver is updating
+	 *  the channel with override/incrementChannelState() which
+	 *  never enable automatic time-in-state updates.  In that case,
+	 *  there is nothing to update and we return success.
+	 */
+	last_ch_update_time = _lastUpdateTimes[channel_index];
+	if (last_ch_update_time == 0) {
+		result = kIOReturnSuccess; goto finish;
+	}
+
+	// figure out the current state (if any)
+	state_index = _currentStates[channel_index];
+
+	// e.g. given 4 4-state channels, the boundary is ch[3].st[3] <- _elems[15]
+	if (channel_index < 0 || channel_index > (_nElements - state_index)
+	    / _channelDimension) {
+		result = kIOReturnOverrun; goto finish;
+	}
+	element_idx = channel_index * _channelDimension + state_index;
+
+	// get the current values
+	kerr = copyElementValues(element_idx, (IOReportElementValues*)&state_values);
+	if (kerr) {
+		result = kerr; goto finish;
+	}
+
+	// calculate time in state
+	currentTime = mach_absolute_time();
+	time_in_state = currentTime - last_ch_update_time;
+	state_values.upticks += time_in_state;
+
+	// and store the values
+	kerr = setElementValues(element_idx,
+	    (IOReportElementValues *)&state_values,
+	    currentTime);
+	if (kerr) {
+		result = kerr; goto finish;
+	}
+
+	// Record basis for next "prior time" calculation
+	_lastUpdateTimes[channel_index] = currentTime;
+
+
+	// success
+	result = kIOReturnSuccess;
+
+finish:
+	return result;
+}
+
+/* static */ OSPtr<IOReportLegendEntry>
+IOStateReporter::createLegend(const uint64_t *channelIDs,
+    const char **channelNames,
+    int channelCount,
+    int nstates,
+    IOReportCategories categories,
+    IOReportUnit unit)
+{
+	IOReportChannelType channelType = {
+		.categories = categories,
+		.report_format = kIOReportFormatState,
+		.nelements = static_cast<uint16_t>(nstates),
+		.element_idx = 0
+	};
+
+	return IOReporter::legendWith(channelIDs, channelNames, channelCount, channelType, unit);
+}