Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[linux-2.6.git] / drivers / acpi / acpica / evmisc.c
1 /******************************************************************************
2  *
3  * Module Name: evmisc - Miscellaneous event manager support functions
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2011, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acevents.h"
47 #include "acnamesp.h"
48 #include "acinterp.h"
49
50 #define _COMPONENT          ACPI_EVENTS
51 ACPI_MODULE_NAME("evmisc")
52
53 /* Local prototypes */
54 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context);
55
56 static u32 acpi_ev_global_lock_handler(void *context);
57
58 static acpi_status acpi_ev_remove_global_lock_handler(void);
59
60 /*******************************************************************************
61  *
62  * FUNCTION:    acpi_ev_is_notify_object
63  *
64  * PARAMETERS:  Node            - Node to check
65  *
66  * RETURN:      TRUE if notifies allowed on this object
67  *
68  * DESCRIPTION: Check type of node for a object that supports notifies.
69  *
70  *              TBD: This could be replaced by a flag bit in the node.
71  *
72  ******************************************************************************/
73
74 u8 acpi_ev_is_notify_object(struct acpi_namespace_node *node)
75 {
76         switch (node->type) {
77         case ACPI_TYPE_DEVICE:
78         case ACPI_TYPE_PROCESSOR:
79         case ACPI_TYPE_THERMAL:
80                 /*
81                  * These are the ONLY objects that can receive ACPI notifications
82                  */
83                 return (TRUE);
84
85         default:
86                 return (FALSE);
87         }
88 }
89
90 /*******************************************************************************
91  *
92  * FUNCTION:    acpi_ev_queue_notify_request
93  *
94  * PARAMETERS:  Node            - NS node for the notified object
95  *              notify_value    - Value from the Notify() request
96  *
97  * RETURN:      Status
98  *
99  * DESCRIPTION: Dispatch a device notification event to a previously
100  *              installed handler.
101  *
102  ******************************************************************************/
103
104 acpi_status
105 acpi_ev_queue_notify_request(struct acpi_namespace_node * node,
106                              u32 notify_value)
107 {
108         union acpi_operand_object *obj_desc;
109         union acpi_operand_object *handler_obj = NULL;
110         union acpi_generic_state *notify_info;
111         acpi_status status = AE_OK;
112
113         ACPI_FUNCTION_NAME(ev_queue_notify_request);
114
115         /*
116          * For value 3 (Ejection Request), some device method may need to be run.
117          * For value 2 (Device Wake) if _PRW exists, the _PS0 method may need
118          *   to be run.
119          * For value 0x80 (Status Change) on the power button or sleep button,
120          *   initiate soft-off or sleep operation?
121          */
122         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
123                           "Dispatching Notify on [%4.4s] Node %p Value 0x%2.2X (%s)\n",
124                           acpi_ut_get_node_name(node), node, notify_value,
125                           acpi_ut_get_notify_name(notify_value)));
126
127         /* Get the notify object attached to the NS Node */
128
129         obj_desc = acpi_ns_get_attached_object(node);
130         if (obj_desc) {
131
132                 /* We have the notify object, Get the right handler */
133
134                 switch (node->type) {
135
136                         /* Notify allowed only on these types */
137
138                 case ACPI_TYPE_DEVICE:
139                 case ACPI_TYPE_THERMAL:
140                 case ACPI_TYPE_PROCESSOR:
141
142                         if (notify_value <= ACPI_MAX_SYS_NOTIFY) {
143                                 handler_obj =
144                                     obj_desc->common_notify.system_notify;
145                         } else {
146                                 handler_obj =
147                                     obj_desc->common_notify.device_notify;
148                         }
149                         break;
150
151                 default:
152
153                         /* All other types are not supported */
154
155                         return (AE_TYPE);
156                 }
157         }
158
159         /*
160          * If there is any handler to run, schedule the dispatcher.
161          * Check for:
162          * 1) Global system notify handler
163          * 2) Global device notify handler
164          * 3) Per-device notify handler
165          */
166         if ((acpi_gbl_system_notify.handler &&
167              (notify_value <= ACPI_MAX_SYS_NOTIFY)) ||
168             (acpi_gbl_device_notify.handler &&
169              (notify_value > ACPI_MAX_SYS_NOTIFY)) || handler_obj) {
170                 notify_info = acpi_ut_create_generic_state();
171                 if (!notify_info) {
172                         return (AE_NO_MEMORY);
173                 }
174
175                 if (!handler_obj) {
176                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
177                                           "Executing system notify handler for Notify (%4.4s, %X) "
178                                           "node %p\n",
179                                           acpi_ut_get_node_name(node),
180                                           notify_value, node));
181                 }
182
183                 notify_info->common.descriptor_type =
184                     ACPI_DESC_TYPE_STATE_NOTIFY;
185                 notify_info->notify.node = node;
186                 notify_info->notify.value = (u16) notify_value;
187                 notify_info->notify.handler_obj = handler_obj;
188
189                 status =
190                     acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_notify_dispatch,
191                                     notify_info);
192                 if (ACPI_FAILURE(status)) {
193                         acpi_ut_delete_generic_state(notify_info);
194                 }
195         } else {
196                 /* There is no notify handler (per-device or system) for this device */
197
198                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
199                                   "No notify handler for Notify (%4.4s, %X) node %p\n",
200                                   acpi_ut_get_node_name(node), notify_value,
201                                   node));
202         }
203
204         return (status);
205 }
206
207 /*******************************************************************************
208  *
209  * FUNCTION:    acpi_ev_notify_dispatch
210  *
211  * PARAMETERS:  Context         - To be passed to the notify handler
212  *
213  * RETURN:      None.
214  *
215  * DESCRIPTION: Dispatch a device notification event to a previously
216  *              installed handler.
217  *
218  ******************************************************************************/
219
220 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
221 {
222         union acpi_generic_state *notify_info =
223             (union acpi_generic_state *)context;
224         acpi_notify_handler global_handler = NULL;
225         void *global_context = NULL;
226         union acpi_operand_object *handler_obj;
227
228         ACPI_FUNCTION_ENTRY();
229
230         /*
231          * We will invoke a global notify handler if installed. This is done
232          * _before_ we invoke the per-device handler attached to the device.
233          */
234         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
235
236                 /* Global system notification handler */
237
238                 if (acpi_gbl_system_notify.handler) {
239                         global_handler = acpi_gbl_system_notify.handler;
240                         global_context = acpi_gbl_system_notify.context;
241                 }
242         } else {
243                 /* Global driver notification handler */
244
245                 if (acpi_gbl_device_notify.handler) {
246                         global_handler = acpi_gbl_device_notify.handler;
247                         global_context = acpi_gbl_device_notify.context;
248                 }
249         }
250
251         /* Invoke the system handler first, if present */
252
253         if (global_handler) {
254                 global_handler(notify_info->notify.node,
255                                notify_info->notify.value, global_context);
256         }
257
258         /* Now invoke the per-device handler, if present */
259
260         handler_obj = notify_info->notify.handler_obj;
261         if (handler_obj) {
262                 struct acpi_object_notify_handler *notifier;
263
264                 notifier = &handler_obj->notify;
265                 while (notifier) {
266                         notifier->handler(notify_info->notify.node,
267                                           notify_info->notify.value,
268                                           notifier->context);
269                         notifier = notifier->next;
270                 }
271         }
272
273         /* All done with the info object */
274
275         acpi_ut_delete_generic_state(notify_info);
276 }
277
278 /*******************************************************************************
279  *
280  * FUNCTION:    acpi_ev_global_lock_handler
281  *
282  * PARAMETERS:  Context         - From thread interface, not used
283  *
284  * RETURN:      ACPI_INTERRUPT_HANDLED
285  *
286  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
287  *              release interrupt occurs.  If there's a thread waiting for
288  *              the global lock, signal it.
289  *
290  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
291  * this is not possible for some reason, a separate thread will have to be
292  * scheduled to do this.
293  *
294  ******************************************************************************/
295 static u8 acpi_ev_global_lock_pending;
296
297 static u32 acpi_ev_global_lock_handler(void *context)
298 {
299         acpi_status status;
300         acpi_cpu_flags flags;
301
302         flags = acpi_os_acquire_lock(acpi_ev_global_lock_pending_lock);
303
304         if (!acpi_ev_global_lock_pending) {
305                 goto out;
306         }
307
308         /* Send a unit to the semaphore */
309
310         status = acpi_os_signal_semaphore(acpi_gbl_global_lock_semaphore, 1);
311         if (ACPI_FAILURE(status)) {
312                 ACPI_ERROR((AE_INFO, "Could not signal Global Lock semaphore"));
313         }
314
315         acpi_ev_global_lock_pending = FALSE;
316
317  out:
318         acpi_os_release_lock(acpi_ev_global_lock_pending_lock, flags);
319
320         return (ACPI_INTERRUPT_HANDLED);
321 }
322
323 /*******************************************************************************
324  *
325  * FUNCTION:    acpi_ev_init_global_lock_handler
326  *
327  * PARAMETERS:  None
328  *
329  * RETURN:      Status
330  *
331  * DESCRIPTION: Install a handler for the global lock release event
332  *
333  ******************************************************************************/
334
335 acpi_status acpi_ev_init_global_lock_handler(void)
336 {
337         acpi_status status;
338
339         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
340
341         /* Attempt installation of the global lock handler */
342
343         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
344                                                   acpi_ev_global_lock_handler,
345                                                   NULL);
346
347         /*
348          * If the global lock does not exist on this platform, the attempt to
349          * enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick).
350          * Map to AE_OK, but mark global lock as not present. Any attempt to
351          * actually use the global lock will be flagged with an error.
352          */
353         if (status == AE_NO_HARDWARE_RESPONSE) {
354                 ACPI_ERROR((AE_INFO,
355                             "No response from Global Lock hardware, disabling lock"));
356
357                 acpi_gbl_global_lock_present = FALSE;
358                 return_ACPI_STATUS(AE_OK);
359         }
360
361         acpi_gbl_global_lock_present = TRUE;
362         return_ACPI_STATUS(status);
363 }
364
365 /*******************************************************************************
366  *
367  * FUNCTION:    acpi_ev_remove_global_lock_handler
368  *
369  * PARAMETERS:  None
370  *
371  * RETURN:      Status
372  *
373  * DESCRIPTION: Remove the handler for the Global Lock
374  *
375  ******************************************************************************/
376
377 static acpi_status acpi_ev_remove_global_lock_handler(void)
378 {
379         acpi_status status;
380
381         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
382
383         acpi_gbl_global_lock_present = FALSE;
384         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
385                                                  acpi_ev_global_lock_handler);
386
387         return_ACPI_STATUS(status);
388 }
389
390 /******************************************************************************
391  *
392  * FUNCTION:    acpi_ev_acquire_global_lock
393  *
394  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
395  *
396  * RETURN:      Status
397  *
398  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
399  *
400  * MUTEX:       Interpreter must be locked
401  *
402  * Note: The original implementation allowed multiple threads to "acquire" the
403  * Global Lock, and the OS would hold the lock until the last thread had
404  * released it. However, this could potentially starve the BIOS out of the
405  * lock, especially in the case where there is a tight handshake between the
406  * Embedded Controller driver and the BIOS. Therefore, this implementation
407  * allows only one thread to acquire the HW Global Lock at a time, and makes
408  * the global lock appear as a standard mutex on the OS side.
409  *
410  *****************************************************************************/
411 static acpi_thread_id acpi_ev_global_lock_thread_id;
412 static int acpi_ev_global_lock_acquired;
413
414 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
415 {
416         acpi_cpu_flags flags;
417         acpi_status status = AE_OK;
418         u8 acquired = FALSE;
419
420         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
421
422         /*
423          * Only one thread can acquire the GL at a time, the global_lock_mutex
424          * enforces this. This interface releases the interpreter if we must wait.
425          */
426         status = acpi_ex_system_wait_mutex(
427                         acpi_gbl_global_lock_mutex->mutex.os_mutex, 0);
428         if (status == AE_TIME) {
429                 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
430                         acpi_ev_global_lock_acquired++;
431                         return AE_OK;
432                 }
433         }
434
435         if (ACPI_FAILURE(status)) {
436                 status = acpi_ex_system_wait_mutex(
437                                 acpi_gbl_global_lock_mutex->mutex.os_mutex,
438                                 timeout);
439         }
440         if (ACPI_FAILURE(status)) {
441                 return_ACPI_STATUS(status);
442         }
443
444         acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
445         acpi_ev_global_lock_acquired++;
446
447         /*
448          * Update the global lock handle and check for wraparound. The handle is
449          * only used for the external global lock interfaces, but it is updated
450          * here to properly handle the case where a single thread may acquire the
451          * lock via both the AML and the acpi_acquire_global_lock interfaces. The
452          * handle is therefore updated on the first acquire from a given thread
453          * regardless of where the acquisition request originated.
454          */
455         acpi_gbl_global_lock_handle++;
456         if (acpi_gbl_global_lock_handle == 0) {
457                 acpi_gbl_global_lock_handle = 1;
458         }
459
460         /*
461          * Make sure that a global lock actually exists. If not, just treat the
462          * lock as a standard mutex.
463          */
464         if (!acpi_gbl_global_lock_present) {
465                 acpi_gbl_global_lock_acquired = TRUE;
466                 return_ACPI_STATUS(AE_OK);
467         }
468
469         flags = acpi_os_acquire_lock(acpi_ev_global_lock_pending_lock);
470
471         do {
472
473                 /* Attempt to acquire the actual hardware lock */
474
475                 ACPI_ACQUIRE_GLOBAL_LOCK(acpi_gbl_FACS, acquired);
476                 if (acquired) {
477                         acpi_gbl_global_lock_acquired = TRUE;
478
479                         ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
480                                           "Acquired hardware Global Lock\n"));
481                         break;
482                 }
483
484                 acpi_ev_global_lock_pending = TRUE;
485
486                 acpi_os_release_lock(acpi_ev_global_lock_pending_lock, flags);
487
488                 /*
489                  * Did not get the lock. The pending bit was set above, and we
490                  * must wait until we get the global lock released interrupt.
491                  */
492                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
493                                   "Waiting for hardware Global Lock\n"));
494
495                 /*
496                  * Wait for handshake with the global lock interrupt handler.
497                  * This interface releases the interpreter if we must wait.
498                  */
499                 status = acpi_ex_system_wait_semaphore(
500                                                 acpi_gbl_global_lock_semaphore,
501                                                 ACPI_WAIT_FOREVER);
502
503                 flags = acpi_os_acquire_lock(acpi_ev_global_lock_pending_lock);
504
505         } while (ACPI_SUCCESS(status));
506
507         acpi_ev_global_lock_pending = FALSE;
508
509         acpi_os_release_lock(acpi_ev_global_lock_pending_lock, flags);
510
511         return_ACPI_STATUS(status);
512 }
513
514 /*******************************************************************************
515  *
516  * FUNCTION:    acpi_ev_release_global_lock
517  *
518  * PARAMETERS:  None
519  *
520  * RETURN:      Status
521  *
522  * DESCRIPTION: Releases ownership of the Global Lock.
523  *
524  ******************************************************************************/
525
526 acpi_status acpi_ev_release_global_lock(void)
527 {
528         u8 pending = FALSE;
529         acpi_status status = AE_OK;
530
531         ACPI_FUNCTION_TRACE(ev_release_global_lock);
532
533         /* Lock must be already acquired */
534
535         if (!acpi_gbl_global_lock_acquired) {
536                 ACPI_WARNING((AE_INFO,
537                               "Cannot release the ACPI Global Lock, it has not been acquired"));
538                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
539         }
540
541         acpi_ev_global_lock_acquired--;
542         if (acpi_ev_global_lock_acquired > 0) {
543                 return AE_OK;
544         }
545
546         if (acpi_gbl_global_lock_present) {
547
548                 /* Allow any thread to release the lock */
549
550                 ACPI_RELEASE_GLOBAL_LOCK(acpi_gbl_FACS, pending);
551
552                 /*
553                  * If the pending bit was set, we must write GBL_RLS to the control
554                  * register
555                  */
556                 if (pending) {
557                         status =
558                             acpi_write_bit_register
559                             (ACPI_BITREG_GLOBAL_LOCK_RELEASE,
560                              ACPI_ENABLE_EVENT);
561                 }
562
563                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
564                                   "Released hardware Global Lock\n"));
565         }
566
567         acpi_gbl_global_lock_acquired = FALSE;
568
569         /* Release the local GL mutex */
570         acpi_ev_global_lock_thread_id = 0;
571         acpi_ev_global_lock_acquired = 0;
572         acpi_os_release_mutex(acpi_gbl_global_lock_mutex->mutex.os_mutex);
573         return_ACPI_STATUS(status);
574 }
575
576 /******************************************************************************
577  *
578  * FUNCTION:    acpi_ev_terminate
579  *
580  * PARAMETERS:  none
581  *
582  * RETURN:      none
583  *
584  * DESCRIPTION: Disable events and free memory allocated for table storage.
585  *
586  ******************************************************************************/
587
588 void acpi_ev_terminate(void)
589 {
590         u32 i;
591         acpi_status status;
592
593         ACPI_FUNCTION_TRACE(ev_terminate);
594
595         if (acpi_gbl_events_initialized) {
596                 /*
597                  * Disable all event-related functionality. In all cases, on error,
598                  * print a message but obviously we don't abort.
599                  */
600
601                 /* Disable all fixed events */
602
603                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
604                         status = acpi_disable_event(i, 0);
605                         if (ACPI_FAILURE(status)) {
606                                 ACPI_ERROR((AE_INFO,
607                                             "Could not disable fixed event %u",
608                                             (u32) i));
609                         }
610                 }
611
612                 /* Disable all GPEs in all GPE blocks */
613
614                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block, NULL);
615
616                 /* Remove SCI handler */
617
618                 status = acpi_ev_remove_sci_handler();
619                 if (ACPI_FAILURE(status)) {
620                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
621                 }
622
623                 status = acpi_ev_remove_global_lock_handler();
624                 if (ACPI_FAILURE(status)) {
625                         ACPI_ERROR((AE_INFO,
626                                     "Could not remove Global Lock handler"));
627                 }
628         }
629
630         /* Deallocate all handler objects installed within GPE info structs */
631
632         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers, NULL);
633
634         /* Return to original mode if necessary */
635
636         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
637                 status = acpi_disable();
638                 if (ACPI_FAILURE(status)) {
639                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
640                 }
641         }
642         return_VOID;
643 }