Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1
2/******************************************************************************
3 *
4 * Module Name: exsystem - Interface to OS services
5 *
6 *****************************************************************************/
7
8/*
9 * Copyright (C) 2000 - 2006, R. Byron Moore
10 * All rights reserved.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions, and the following disclaimer,
17 * without modification.
18 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
19 * substantially similar to the "NO WARRANTY" disclaimer below
20 * ("Disclaimer") and any redistribution must be conditioned upon
21 * including a substantially similar Disclaimer requirement for further
22 * binary redistribution.
23 * 3. Neither the names of the above-listed copyright holders nor the names
24 * of any contributors may be used to endorse or promote products derived
25 * from this software without specific prior written permission.
26 *
27 * Alternatively, this software may be distributed under the terms of the
28 * GNU General Public License ("GPL") version 2 as published by the Free
29 * Software Foundation.
30 *
31 * NO WARRANTY
32 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
33 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
34 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
35 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
36 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
41 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
42 * POSSIBILITY OF SUCH DAMAGES.
43 */
44
45#include <acpi/acpi.h>
46#include <acpi/acinterp.h>
47#include <acpi/acevents.h>
48
49#define _COMPONENT ACPI_EXECUTER
50ACPI_MODULE_NAME("exsystem")
51
52/*******************************************************************************
53 *
54 * FUNCTION: acpi_ex_system_wait_semaphore
55 *
56 * PARAMETERS: Semaphore - Semaphore to wait on
57 * Timeout - Max time to wait
58 *
59 * RETURN: Status
60 *
61 * DESCRIPTION: Implements a semaphore wait with a check to see if the
62 * semaphore is available immediately. If it is not, the
63 * interpreter is released.
64 *
65 ******************************************************************************/
66acpi_status acpi_ex_system_wait_semaphore(acpi_handle semaphore, u16 timeout)
67{
68 acpi_status status;
69 acpi_status status2;
70
71 ACPI_FUNCTION_TRACE("ex_system_wait_semaphore");
72
73 status = acpi_os_wait_semaphore(semaphore, 1, 0);
74 if (ACPI_SUCCESS(status)) {
75 return_ACPI_STATUS(status);
76 }
77
78 if (status == AE_TIME) {
79 /* We must wait, so unlock the interpreter */
80
81 acpi_ex_exit_interpreter();
82
83 status = acpi_os_wait_semaphore(semaphore, 1, timeout);
84
85 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
86 "*** Thread awake after blocking, %s\n",
87 acpi_format_exception(status)));
88
89 /* Reacquire the interpreter */
90
91 status2 = acpi_ex_enter_interpreter();
92 if (ACPI_FAILURE(status2)) {
93 /* Report fatal error, could not acquire interpreter */
94
95 return_ACPI_STATUS(status2);
96 }
97 }
98
99 return_ACPI_STATUS(status);
100}
101
102/*******************************************************************************
103 *
104 * FUNCTION: acpi_ex_system_do_stall
105 *
106 * PARAMETERS: how_long - The amount of time to stall,
107 * in microseconds
108 *
109 * RETURN: Status
110 *
111 * DESCRIPTION: Suspend running thread for specified amount of time.
112 * Note: ACPI specification requires that Stall() does not
113 * relinquish the processor, and delays longer than 100 usec
114 * should use Sleep() instead. We allow stalls up to 255 usec
115 * for compatibility with other interpreters and existing BIOSs.
116 *
117 ******************************************************************************/
118
119acpi_status acpi_ex_system_do_stall(u32 how_long)
120{
121 acpi_status status = AE_OK;
122
123 ACPI_FUNCTION_ENTRY();
124
125 if (how_long > 255) { /* 255 microseconds */
126 /*
127 * Longer than 255 usec, this is an error
128 *
129 * (ACPI specifies 100 usec as max, but this gives some slack in
130 * order to support existing BIOSs)
131 */
132 ACPI_ERROR((AE_INFO, "Time parameter is too large (%d)",
133 how_long));
134 status = AE_AML_OPERAND_VALUE;
135 } else {
136 acpi_os_stall(how_long);
137 }
138
139 return (status);
140}
141
142/*******************************************************************************
143 *
144 * FUNCTION: acpi_ex_system_do_suspend
145 *
146 * PARAMETERS: how_long - The amount of time to suspend,
147 * in milliseconds
148 *
149 * RETURN: None
150 *
151 * DESCRIPTION: Suspend running thread for specified amount of time.
152 *
153 ******************************************************************************/
154
155acpi_status acpi_ex_system_do_suspend(acpi_integer how_long)
156{
157 acpi_status status;
158
159 ACPI_FUNCTION_ENTRY();
160
161 /* Since this thread will sleep, we must release the interpreter */
162
163 acpi_ex_exit_interpreter();
164
165 acpi_os_sleep(how_long);
166
167 /* And now we must get the interpreter again */
168
169 status = acpi_ex_enter_interpreter();
170 return (status);
171}
172
173/*******************************************************************************
174 *
175 * FUNCTION: acpi_ex_system_acquire_mutex
176 *
177 * PARAMETERS: time_desc - The 'time to delay' object descriptor
178 * obj_desc - The object descriptor for this op
179 *
180 * RETURN: Status
181 *
182 * DESCRIPTION: Provides an access point to perform synchronization operations
183 * within the AML. This function will cause a lock to be generated
184 * for the Mutex pointed to by obj_desc.
185 *
186 ******************************************************************************/
187
188acpi_status
189acpi_ex_system_acquire_mutex(union acpi_operand_object * time_desc,
190 union acpi_operand_object * obj_desc)
191{
192 acpi_status status = AE_OK;
193
194 ACPI_FUNCTION_TRACE_PTR("ex_system_acquire_mutex", obj_desc);
195
196 if (!obj_desc) {
197 return_ACPI_STATUS(AE_BAD_PARAMETER);
198 }
199
200 /* Support for the _GL_ Mutex object -- go get the global lock */
201
202 if (obj_desc->mutex.semaphore == acpi_gbl_global_lock_semaphore) {
203 status =
204 acpi_ev_acquire_global_lock((u16) time_desc->integer.value);
205 return_ACPI_STATUS(status);
206 }
207
208 status = acpi_ex_system_wait_semaphore(obj_desc->mutex.semaphore,
209 (u16) time_desc->integer.value);
210 return_ACPI_STATUS(status);
211}
212
213/*******************************************************************************
214 *
215 * FUNCTION: acpi_ex_system_release_mutex
216 *
217 * PARAMETERS: obj_desc - The object descriptor for this op
218 *
219 * RETURN: Status
220 *
221 * DESCRIPTION: Provides an access point to perform synchronization operations
222 * within the AML. This operation is a request to release a
223 * previously acquired Mutex. If the Mutex variable is set then
224 * it will be decremented.
225 *
226 ******************************************************************************/
227
228acpi_status acpi_ex_system_release_mutex(union acpi_operand_object *obj_desc)
229{
230 acpi_status status = AE_OK;
231
232 ACPI_FUNCTION_TRACE("ex_system_release_mutex");
233
234 if (!obj_desc) {
235 return_ACPI_STATUS(AE_BAD_PARAMETER);
236 }
237
238 /* Support for the _GL_ Mutex object -- release the global lock */
239
240 if (obj_desc->mutex.semaphore == acpi_gbl_global_lock_semaphore) {
241 status = acpi_ev_release_global_lock();
242 return_ACPI_STATUS(status);
243 }
244
245 status = acpi_os_signal_semaphore(obj_desc->mutex.semaphore, 1);
246 return_ACPI_STATUS(status);
247}
248
249/*******************************************************************************
250 *
251 * FUNCTION: acpi_ex_system_signal_event
252 *
253 * PARAMETERS: obj_desc - The object descriptor for this op
254 *
255 * RETURN: Status
256 *
257 * DESCRIPTION: Provides an access point to perform synchronization operations
258 * within the AML.
259 *
260 ******************************************************************************/
261
262acpi_status acpi_ex_system_signal_event(union acpi_operand_object *obj_desc)
263{
264 acpi_status status = AE_OK;
265
266 ACPI_FUNCTION_TRACE("ex_system_signal_event");
267
268 if (obj_desc) {
269 status = acpi_os_signal_semaphore(obj_desc->event.semaphore, 1);
270 }
271
272 return_ACPI_STATUS(status);
273}
274
275/*******************************************************************************
276 *
277 * FUNCTION: acpi_ex_system_wait_event
278 *
279 * PARAMETERS: time_desc - The 'time to delay' object descriptor
280 * obj_desc - The object descriptor for this op
281 *
282 * RETURN: Status
283 *
284 * DESCRIPTION: Provides an access point to perform synchronization operations
285 * within the AML. This operation is a request to wait for an
286 * event.
287 *
288 ******************************************************************************/
289
290acpi_status
291acpi_ex_system_wait_event(union acpi_operand_object *time_desc,
292 union acpi_operand_object *obj_desc)
293{
294 acpi_status status = AE_OK;
295
296 ACPI_FUNCTION_TRACE("ex_system_wait_event");
297
298 if (obj_desc) {
299 status =
300 acpi_ex_system_wait_semaphore(obj_desc->event.semaphore,
301 (u16) time_desc->integer.
302 value);
303 }
304
305 return_ACPI_STATUS(status);
306}
307
308/*******************************************************************************
309 *
310 * FUNCTION: acpi_ex_system_reset_event
311 *
312 * PARAMETERS: obj_desc - The object descriptor for this op
313 *
314 * RETURN: Status
315 *
316 * DESCRIPTION: Reset an event to a known state.
317 *
318 ******************************************************************************/
319
320acpi_status acpi_ex_system_reset_event(union acpi_operand_object *obj_desc)
321{
322 acpi_status status = AE_OK;
323 void *temp_semaphore;
324
325 ACPI_FUNCTION_ENTRY();
326
327 /*
328 * We are going to simply delete the existing semaphore and
329 * create a new one!
330 */
331 status =
332 acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
333 if (ACPI_SUCCESS(status)) {
334 (void)acpi_os_delete_semaphore(obj_desc->event.semaphore);
335 obj_desc->event.semaphore = temp_semaphore;
336 }
337
338 return (status);
339}