Merge commit 'kumar/next' into next
[linux-2.6] / drivers / acpi / acpica / evmisc.c
1 /******************************************************************************
2  *
3  * Module Name: evmisc - Miscellaneous event manager support functions
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2008, 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) node %p\n",
178                                           acpi_ut_get_node_name(node),
179                                           notify_value, node));
180                 }
181
182                 notify_info->common.descriptor_type =
183                     ACPI_DESC_TYPE_STATE_NOTIFY;
184                 notify_info->notify.node = node;
185                 notify_info->notify.value = (u16) notify_value;
186                 notify_info->notify.handler_obj = handler_obj;
187
188                 status =
189                     acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_notify_dispatch,
190                                     notify_info);
191                 if (ACPI_FAILURE(status)) {
192                         acpi_ut_delete_generic_state(notify_info);
193                 }
194         } else {
195                 /* There is no notify handler (per-device or system) for this device */
196
197                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
198                                   "No notify handler for Notify (%4.4s, %X) node %p\n",
199                                   acpi_ut_get_node_name(node), notify_value,
200                                   node));
201         }
202
203         return (status);
204 }
205
206 /*******************************************************************************
207  *
208  * FUNCTION:    acpi_ev_notify_dispatch
209  *
210  * PARAMETERS:  Context         - To be passed to the notify handler
211  *
212  * RETURN:      None.
213  *
214  * DESCRIPTION: Dispatch a device notification event to a previously
215  *              installed handler.
216  *
217  ******************************************************************************/
218
219 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
220 {
221         union acpi_generic_state *notify_info =
222             (union acpi_generic_state *)context;
223         acpi_notify_handler global_handler = NULL;
224         void *global_context = NULL;
225         union acpi_operand_object *handler_obj;
226
227         ACPI_FUNCTION_ENTRY();
228
229         /*
230          * We will invoke a global notify handler if installed. This is done
231          * _before_ we invoke the per-device handler attached to the device.
232          */
233         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
234
235                 /* Global system notification handler */
236
237                 if (acpi_gbl_system_notify.handler) {
238                         global_handler = acpi_gbl_system_notify.handler;
239                         global_context = acpi_gbl_system_notify.context;
240                 }
241         } else {
242                 /* Global driver notification handler */
243
244                 if (acpi_gbl_device_notify.handler) {
245                         global_handler = acpi_gbl_device_notify.handler;
246                         global_context = acpi_gbl_device_notify.context;
247                 }
248         }
249
250         /* Invoke the system handler first, if present */
251
252         if (global_handler) {
253                 global_handler(notify_info->notify.node,
254                                notify_info->notify.value, global_context);
255         }
256
257         /* Now invoke the per-device handler, if present */
258
259         handler_obj = notify_info->notify.handler_obj;
260         if (handler_obj) {
261                 handler_obj->notify.handler(notify_info->notify.node,
262                                             notify_info->notify.value,
263                                             handler_obj->notify.context);
264         }
265
266         /* All done with the info object */
267
268         acpi_ut_delete_generic_state(notify_info);
269 }
270
271 /*******************************************************************************
272  *
273  * FUNCTION:    acpi_ev_global_lock_handler
274  *
275  * PARAMETERS:  Context         - From thread interface, not used
276  *
277  * RETURN:      ACPI_INTERRUPT_HANDLED
278  *
279  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
280  *              release interrupt occurs. Attempt to acquire the global lock,
281  *              if successful, signal the thread waiting for the lock.
282  *
283  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
284  * this is not possible for some reason, a separate thread will have to be
285  * scheduled to do this.
286  *
287  ******************************************************************************/
288
289 static u32 acpi_ev_global_lock_handler(void *context)
290 {
291         u8 acquired = FALSE;
292
293         /*
294          * Attempt to get the lock.
295          *
296          * If we don't get it now, it will be marked pending and we will
297          * take another interrupt when it becomes free.
298          */
299         ACPI_ACQUIRE_GLOBAL_LOCK(acpi_gbl_FACS, acquired);
300         if (acquired) {
301
302                 /* Got the lock, now wake all threads waiting for it */
303
304                 acpi_gbl_global_lock_acquired = TRUE;
305                 /* Send a unit to the semaphore */
306
307                 if (ACPI_FAILURE
308                     (acpi_os_signal_semaphore
309                      (acpi_gbl_global_lock_semaphore, 1))) {
310                         ACPI_ERROR((AE_INFO,
311                                     "Could not signal Global Lock semaphore"));
312                 }
313         }
314
315         return (ACPI_INTERRUPT_HANDLED);
316 }
317
318 /*******************************************************************************
319  *
320  * FUNCTION:    acpi_ev_init_global_lock_handler
321  *
322  * PARAMETERS:  None
323  *
324  * RETURN:      Status
325  *
326  * DESCRIPTION: Install a handler for the global lock release event
327  *
328  ******************************************************************************/
329
330 acpi_status acpi_ev_init_global_lock_handler(void)
331 {
332         acpi_status status;
333
334         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
335
336         /* Attempt installation of the global lock handler */
337
338         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
339                                                   acpi_ev_global_lock_handler,
340                                                   NULL);
341
342         /*
343          * If the global lock does not exist on this platform, the attempt to
344          * enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick).
345          * Map to AE_OK, but mark global lock as not present. Any attempt to
346          * actually use the global lock will be flagged with an error.
347          */
348         if (status == AE_NO_HARDWARE_RESPONSE) {
349                 ACPI_ERROR((AE_INFO,
350                             "No response from Global Lock hardware, disabling lock"));
351
352                 acpi_gbl_global_lock_present = FALSE;
353                 return_ACPI_STATUS(AE_OK);
354         }
355
356         acpi_gbl_global_lock_present = TRUE;
357         return_ACPI_STATUS(status);
358 }
359
360 /*******************************************************************************
361  *
362  * FUNCTION:    acpi_ev_remove_global_lock_handler
363  *
364  * PARAMETERS:  None
365  *
366  * RETURN:      Status
367  *
368  * DESCRIPTION: Remove the handler for the Global Lock
369  *
370  ******************************************************************************/
371
372 static acpi_status acpi_ev_remove_global_lock_handler(void)
373 {
374         acpi_status status;
375
376         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
377
378         acpi_gbl_global_lock_present = FALSE;
379         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
380                                                  acpi_ev_global_lock_handler);
381
382         return_ACPI_STATUS(status);
383 }
384
385 /******************************************************************************
386  *
387  * FUNCTION:    acpi_ev_acquire_global_lock
388  *
389  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
390  *
391  * RETURN:      Status
392  *
393  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
394  *
395  * MUTEX:       Interpreter must be locked
396  *
397  * Note: The original implementation allowed multiple threads to "acquire" the
398  * Global Lock, and the OS would hold the lock until the last thread had
399  * released it. However, this could potentially starve the BIOS out of the
400  * lock, especially in the case where there is a tight handshake between the
401  * Embedded Controller driver and the BIOS. Therefore, this implementation
402  * allows only one thread to acquire the HW Global Lock at a time, and makes
403  * the global lock appear as a standard mutex on the OS side.
404  *
405  *****************************************************************************/
406 static acpi_thread_id acpi_ev_global_lock_thread_id;
407 static int acpi_ev_global_lock_acquired;
408
409 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
410 {
411         acpi_status status = AE_OK;
412         u8 acquired = FALSE;
413
414         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
415
416         /*
417          * Only one thread can acquire the GL at a time, the global_lock_mutex
418          * enforces this. This interface releases the interpreter if we must wait.
419          */
420         status = acpi_ex_system_wait_mutex(
421                         acpi_gbl_global_lock_mutex->mutex.os_mutex, 0);
422         if (status == AE_TIME) {
423                 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
424                         acpi_ev_global_lock_acquired++;
425                         return AE_OK;
426                 }
427         }
428
429         if (ACPI_FAILURE(status)) {
430                 status = acpi_ex_system_wait_mutex(
431                                 acpi_gbl_global_lock_mutex->mutex.os_mutex,
432                                 timeout);
433         }
434         if (ACPI_FAILURE(status)) {
435                 return_ACPI_STATUS(status);
436         }
437
438         acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
439         acpi_ev_global_lock_acquired++;
440
441         /*
442          * Update the global lock handle and check for wraparound. The handle is
443          * only used for the external global lock interfaces, but it is updated
444          * here to properly handle the case where a single thread may acquire the
445          * lock via both the AML and the acpi_acquire_global_lock interfaces. The
446          * handle is therefore updated on the first acquire from a given thread
447          * regardless of where the acquisition request originated.
448          */
449         acpi_gbl_global_lock_handle++;
450         if (acpi_gbl_global_lock_handle == 0) {
451                 acpi_gbl_global_lock_handle = 1;
452         }
453
454         /*
455          * Make sure that a global lock actually exists. If not, just treat the
456          * lock as a standard mutex.
457          */
458         if (!acpi_gbl_global_lock_present) {
459                 acpi_gbl_global_lock_acquired = TRUE;
460                 return_ACPI_STATUS(AE_OK);
461         }
462
463         /* Attempt to acquire the actual hardware lock */
464
465         ACPI_ACQUIRE_GLOBAL_LOCK(acpi_gbl_FACS, acquired);
466         if (acquired) {
467
468                 /* We got the lock */
469
470                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
471                                   "Acquired hardware Global Lock\n"));
472
473                 acpi_gbl_global_lock_acquired = TRUE;
474                 return_ACPI_STATUS(AE_OK);
475         }
476
477         /*
478          * Did not get the lock. The pending bit was set above, and we must now
479          * wait until we get the global lock released interrupt.
480          */
481         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n"));
482
483         /*
484          * Wait for handshake with the global lock interrupt handler.
485          * This interface releases the interpreter if we must wait.
486          */
487         status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore,
488                                                ACPI_WAIT_FOREVER);
489
490         return_ACPI_STATUS(status);
491 }
492
493 /*******************************************************************************
494  *
495  * FUNCTION:    acpi_ev_release_global_lock
496  *
497  * PARAMETERS:  None
498  *
499  * RETURN:      Status
500  *
501  * DESCRIPTION: Releases ownership of the Global Lock.
502  *
503  ******************************************************************************/
504
505 acpi_status acpi_ev_release_global_lock(void)
506 {
507         u8 pending = FALSE;
508         acpi_status status = AE_OK;
509
510         ACPI_FUNCTION_TRACE(ev_release_global_lock);
511
512         /* Lock must be already acquired */
513
514         if (!acpi_gbl_global_lock_acquired) {
515                 ACPI_WARNING((AE_INFO,
516                               "Cannot release the ACPI Global Lock, it has not been acquired"));
517                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
518         }
519
520         acpi_ev_global_lock_acquired--;
521         if (acpi_ev_global_lock_acquired > 0) {
522                 return AE_OK;
523         }
524
525         if (acpi_gbl_global_lock_present) {
526
527                 /* Allow any thread to release the lock */
528
529                 ACPI_RELEASE_GLOBAL_LOCK(acpi_gbl_FACS, pending);
530
531                 /*
532                  * If the pending bit was set, we must write GBL_RLS to the control
533                  * register
534                  */
535                 if (pending) {
536                         status =
537                             acpi_set_register(ACPI_BITREG_GLOBAL_LOCK_RELEASE,
538                                               1);
539                 }
540
541                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
542                                   "Released hardware Global Lock\n"));
543         }
544
545         acpi_gbl_global_lock_acquired = FALSE;
546
547         /* Release the local GL mutex */
548         acpi_ev_global_lock_thread_id = NULL;
549         acpi_ev_global_lock_acquired = 0;
550         acpi_os_release_mutex(acpi_gbl_global_lock_mutex->mutex.os_mutex);
551         return_ACPI_STATUS(status);
552 }
553
554 /******************************************************************************
555  *
556  * FUNCTION:    acpi_ev_terminate
557  *
558  * PARAMETERS:  none
559  *
560  * RETURN:      none
561  *
562  * DESCRIPTION: Disable events and free memory allocated for table storage.
563  *
564  ******************************************************************************/
565
566 void acpi_ev_terminate(void)
567 {
568         u32 i;
569         acpi_status status;
570
571         ACPI_FUNCTION_TRACE(ev_terminate);
572
573         if (acpi_gbl_events_initialized) {
574                 /*
575                  * Disable all event-related functionality. In all cases, on error,
576                  * print a message but obviously we don't abort.
577                  */
578
579                 /* Disable all fixed events */
580
581                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
582                         status = acpi_disable_event(i, 0);
583                         if (ACPI_FAILURE(status)) {
584                                 ACPI_ERROR((AE_INFO,
585                                             "Could not disable fixed event %d",
586                                             (u32) i));
587                         }
588                 }
589
590                 /* Disable all GPEs in all GPE blocks */
591
592                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block, NULL);
593
594                 /* Remove SCI handler */
595
596                 status = acpi_ev_remove_sci_handler();
597                 if (ACPI_FAILURE(status)) {
598                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
599                 }
600
601                 status = acpi_ev_remove_global_lock_handler();
602                 if (ACPI_FAILURE(status)) {
603                         ACPI_ERROR((AE_INFO,
604                                     "Could not remove Global Lock handler"));
605                 }
606         }
607
608         /* Deallocate all handler objects installed within GPE info structs */
609
610         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers, NULL);
611
612         /* Return to original mode if necessary */
613
614         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
615                 status = acpi_disable();
616                 if (ACPI_FAILURE(status)) {
617                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
618                 }
619         }
620         return_VOID;
621 }