1/*
2 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28#include <IOKit/pwr_mgt/IOPM.h>
29#include <IOKit/pwr_mgt/IOPMinformeeList.h>
30#include <IOKit/pwr_mgt/IOPMinformee.h>
31
32#define super OSObject
33OSDefineMetaClassAndStructors(IOPMinformeeList,OSObject)
34
35//*********************************************************************************
36// init
37//
38//*********************************************************************************
39void IOPMinformeeList::initialize ( void )
40{
41 firstItem = NULL;
42 length = 0;
43}
44
45//******************************************************************************
46// getSharedRecursiveLock
47//
48//******************************************************************************
49IORecursiveLock *IOPMinformeeList::getSharedRecursiveLock( void )
50{
51 static IORecursiveLock *sharedListLock = NULL;
52
53 /* A running system could have 50-60+ instances of IOPMInformeeList.
54 * They'll share this lock, since list insertion and removal is relatively
55 * rare, and generally tied to major events like device discovery.
56 *
57 * getSharedRecursiveLock() is called from IOStartIOKit to initialize
58 * the sharedListLock before any IOPMinformeeLists are instantiated.
59 *
60 * The IOPMinformeeList class will be around for the lifetime of the system,
61 * we don't worry about freeing this lock.
62 */
63
64 if ( NULL == sharedListLock )
65 {
66 sharedListLock = IORecursiveLockAlloc();
67 }
68 return sharedListLock;
69}
70
71 //*********************************************************************************
72// appendNewInformee
73 //
74 //*********************************************************************************
75IOPMinformee *IOPMinformeeList::appendNewInformee ( IOService * newObject )
76{
77 IOPMinformee * newInformee;
78
79 if (!newObject)
80 return NULL;
81
82 newInformee = IOPMinformee::withObject (newObject);
83
84 if (!newInformee)
85 return NULL;
86
87 if( IOPMNoErr == addToList (newInformee))
88 return newInformee;
89 else
90 return NULL;
91}
92
93
94//*********************************************************************************
95// addToList
96// *OBSOLETE* do not call from outside of this file.
97// Try appendNewInformee() instead
98//*********************************************************************************
99IOReturn IOPMinformeeList::addToList ( IOPMinformee * newInformee )
100{
101 IOPMinformee * nextInformee;
102 IORecursiveLock *listLock = getSharedRecursiveLock();
103
104 if(!listLock)
105 return kIOReturnError;
106
107 IORecursiveLockLock(listLock);
108 nextInformee = firstItem;
109
110 // Is new object already in the list?
111 while ( nextInformee != NULL )
112 {
113 if ( nextInformee->whatObject == newInformee->whatObject )
114 {
115 // object is present; just exit
116 goto unlock_and_exit;
117 }
118 nextInformee = nextInList(nextInformee);
119 }
120
121 // add it to the front of the list
122 newInformee->nextInList = firstItem;
123 firstItem = newInformee;
124 length++;
125
126unlock_and_exit:
127 IORecursiveLockUnlock(listLock);
128 return IOPMNoErr;
129}
130
131
132//*********************************************************************************
133// removeFromList
134//
135// Find the item in the list, unlink it, and free it.
136//*********************************************************************************
137
138IOReturn IOPMinformeeList::removeFromList ( IOService * theItem )
139{
140 IOPMinformee * item = firstItem;
141 IOPMinformee * temp;
142 IORecursiveLock *listLock = getSharedRecursiveLock();
143
144 if ( NULL == item )
145 return IOPMNoErr;
146 if(!listLock)
147 return kIOReturnError;
148
149 IORecursiveLockLock( listLock );
150
151 if ( item->whatObject == theItem )
152 {
153 firstItem = item->nextInList;
154 length--;
155 item->release();
156 goto unlock_and_exit;
157 }
158
159 while ( item->nextInList != NULL )
160 {
161 if ( item->nextInList->whatObject == theItem )
162 {
163 temp = item->nextInList;
164 item->nextInList = temp->nextInList;
165 length--;
166 temp->release();
167 goto unlock_and_exit;
168 }
169 item = item->nextInList;
170 }
171
172unlock_and_exit:
173 IORecursiveLockUnlock(listLock);
174 return IOPMNoErr;
175}
176
177
178//*********************************************************************************
179// firstInList
180//
181//*********************************************************************************
182
183IOPMinformee * IOPMinformeeList::firstInList ( void )
184{
185 return firstItem;
186}
187
188//*********************************************************************************
189// nextInList
190//
191//*********************************************************************************
192
193IOPMinformee * IOPMinformeeList::nextInList ( IOPMinformee * currentItem )
194{
195 if ( currentItem != NULL ) {
196 return (currentItem->nextInList);
197 }
198 return NULL;
199}
200
201//*********************************************************************************
202// numberOfItems
203//
204//*********************************************************************************
205
206unsigned long IOPMinformeeList::numberOfItems ( void )
207{
208 return length;
209}
210
211//*********************************************************************************
212// findItem
213//
214// Look through the list for the one which points to the object identified
215// by the parameter. Return a pointer to the list item or NULL.
216//*********************************************************************************
217
218IOPMinformee * IOPMinformeeList::findItem ( IOService * driverOrChild )
219{
220 IOPMinformee * nextObject;
221
222 nextObject = firstInList();
223 while ( nextObject != NULL ) {
224 if ( nextObject->whatObject == driverOrChild ) {
225 return nextObject;
226 }
227 nextObject = nextInList(nextObject);
228 }
229 return NULL;
230}
231
232
233
234//*********************************************************************************
235// free
236//
237// Free all items in the list, and then free the list itself
238//*********************************************************************************
239
240void IOPMinformeeList::free (void )
241{
242 IOPMinformee * next = firstItem;
243
244 while ( next != NULL ) {
245 firstItem = next->nextInList;
246 length--;
247 next->release();
248 next = firstItem;
249 }
250super::free();
251}
252
253