Merge branch 'drm-patches' of master.kernel.org:/pub/scm/linux/kernel/git/airlied...
[linux-2.6] / drivers / acpi / events / evmisc.c
1 /******************************************************************************
2  *
3  * Module Name: evmisc - Miscellaneous event manager support functions
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2007, R. Byron Moore
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 <acpi/acevents.h>
46 #include <acpi/acnamesp.h>
47 #include <acpi/acinterp.h>
48
49 #define _COMPONENT          ACPI_EVENTS
50 ACPI_MODULE_NAME("evmisc")
51
52 /* Names for Notify() values, used for debug output */
53 #ifdef ACPI_DEBUG_OUTPUT
54 static const char *acpi_notify_value_names[] = {
55         "Bus Check",
56         "Device Check",
57         "Device Wake",
58         "Eject Request",
59         "Device Check Light",
60         "Frequency Mismatch",
61         "Bus Mode Mismatch",
62         "Power Fault"
63 };
64 #endif
65
66 /* Pointer to FACS needed for the Global Lock */
67
68 static struct acpi_table_facs *facs = NULL;
69
70 /* Local prototypes */
71
72 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context);
73
74 static u32 acpi_ev_global_lock_handler(void *context);
75
76 static acpi_status acpi_ev_remove_global_lock_handler(void);
77
78 /*******************************************************************************
79  *
80  * FUNCTION:    acpi_ev_is_notify_object
81  *
82  * PARAMETERS:  Node            - Node to check
83  *
84  * RETURN:      TRUE if notifies allowed on this object
85  *
86  * DESCRIPTION: Check type of node for a object that supports notifies.
87  *
88  *              TBD: This could be replaced by a flag bit in the node.
89  *
90  ******************************************************************************/
91
92 u8 acpi_ev_is_notify_object(struct acpi_namespace_node *node)
93 {
94         switch (node->type) {
95         case ACPI_TYPE_DEVICE:
96         case ACPI_TYPE_PROCESSOR:
97         case ACPI_TYPE_POWER:
98         case ACPI_TYPE_THERMAL:
99                 /*
100                  * These are the ONLY objects that can receive ACPI notifications
101                  */
102                 return (TRUE);
103
104         default:
105                 return (FALSE);
106         }
107 }
108
109 /*******************************************************************************
110  *
111  * FUNCTION:    acpi_ev_queue_notify_request
112  *
113  * PARAMETERS:  Node            - NS node for the notified object
114  *              notify_value    - Value from the Notify() request
115  *
116  * RETURN:      Status
117  *
118  * DESCRIPTION: Dispatch a device notification event to a previously
119  *              installed handler.
120  *
121  ******************************************************************************/
122
123 acpi_status
124 acpi_ev_queue_notify_request(struct acpi_namespace_node * node,
125                              u32 notify_value)
126 {
127         union acpi_operand_object *obj_desc;
128         union acpi_operand_object *handler_obj = NULL;
129         union acpi_generic_state *notify_info;
130         acpi_status status = AE_OK;
131
132         ACPI_FUNCTION_NAME(ev_queue_notify_request);
133
134         /*
135          * For value 3 (Ejection Request), some device method may need to be run.
136          * For value 2 (Device Wake) if _PRW exists, the _PS0 method may need
137          *   to be run.
138          * For value 0x80 (Status Change) on the power button or sleep button,
139          *   initiate soft-off or sleep operation?
140          */
141         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
142                           "Dispatching Notify(%X) on node %p\n", notify_value,
143                           node));
144
145         if (notify_value <= 7) {
146                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Notify value: %s\n",
147                                   acpi_notify_value_names[notify_value]));
148         } else {
149                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
150                                   "Notify value: 0x%2.2X **Device Specific**\n",
151                                   notify_value));
152         }
153
154         /* Get the notify object attached to the NS Node */
155
156         obj_desc = acpi_ns_get_attached_object(node);
157         if (obj_desc) {
158
159                 /* We have the notify object, Get the right handler */
160
161                 switch (node->type) {
162                 case ACPI_TYPE_DEVICE:
163                 case ACPI_TYPE_THERMAL:
164                 case ACPI_TYPE_PROCESSOR:
165                 case ACPI_TYPE_POWER:
166
167                         if (notify_value <= ACPI_MAX_SYS_NOTIFY) {
168                                 handler_obj =
169                                     obj_desc->common_notify.system_notify;
170                         } else {
171                                 handler_obj =
172                                     obj_desc->common_notify.device_notify;
173                         }
174                         break;
175
176                 default:
177                         /* All other types are not supported */
178                         return (AE_TYPE);
179                 }
180         }
181
182         /* If there is any handler to run, schedule the dispatcher */
183
184         if ((acpi_gbl_system_notify.handler
185              && (notify_value <= ACPI_MAX_SYS_NOTIFY))
186             || (acpi_gbl_device_notify.handler
187                 && (notify_value > ACPI_MAX_SYS_NOTIFY)) || handler_obj) {
188                 notify_info = acpi_ut_create_generic_state();
189                 if (!notify_info) {
190                         return (AE_NO_MEMORY);
191                 }
192
193                 notify_info->common.descriptor_type =
194                     ACPI_DESC_TYPE_STATE_NOTIFY;
195                 notify_info->notify.node = node;
196                 notify_info->notify.value = (u16) notify_value;
197                 notify_info->notify.handler_obj = handler_obj;
198
199                 acpi_ex_exit_interpreter();
200
201                 acpi_ev_notify_dispatch(notify_info);
202
203                 status = acpi_ex_enter_interpreter();
204                 if (ACPI_FAILURE(status)) {
205                         return_ACPI_STATUS(status);
206                 }
207
208         }
209
210         if (!handler_obj) {
211                 /*
212                  * There is no per-device notify handler for this device.
213                  * This may or may not be a problem.
214                  */
215                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
216                                   "No notify handler for Notify(%4.4s, %X) node %p\n",
217                                   acpi_ut_get_node_name(node), notify_value,
218                                   node));
219         }
220
221         return (status);
222 }
223
224 /*******************************************************************************
225  *
226  * FUNCTION:    acpi_ev_notify_dispatch
227  *
228  * PARAMETERS:  Context         - To be passed to the notify handler
229  *
230  * RETURN:      None.
231  *
232  * DESCRIPTION: Dispatch a device notification event to a previously
233  *              installed handler.
234  *
235  ******************************************************************************/
236
237 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
238 {
239         union acpi_generic_state *notify_info =
240             (union acpi_generic_state *)context;
241         acpi_notify_handler global_handler = NULL;
242         void *global_context = NULL;
243         union acpi_operand_object *handler_obj;
244
245         ACPI_FUNCTION_ENTRY();
246
247         /*
248          * We will invoke a global notify handler if installed.
249          * This is done _before_ we invoke the per-device handler attached
250          * to the device.
251          */
252         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
253
254                 /* Global system notification handler */
255
256                 if (acpi_gbl_system_notify.handler) {
257                         global_handler = acpi_gbl_system_notify.handler;
258                         global_context = acpi_gbl_system_notify.context;
259                 }
260         } else {
261                 /* Global driver notification handler */
262
263                 if (acpi_gbl_device_notify.handler) {
264                         global_handler = acpi_gbl_device_notify.handler;
265                         global_context = acpi_gbl_device_notify.context;
266                 }
267         }
268
269         /* Invoke the system handler first, if present */
270
271         if (global_handler) {
272                 global_handler(notify_info->notify.node,
273                                notify_info->notify.value, global_context);
274         }
275
276         /* Now invoke the per-device handler, if present */
277
278         handler_obj = notify_info->notify.handler_obj;
279         if (handler_obj) {
280                 handler_obj->notify.handler(notify_info->notify.node,
281                                             notify_info->notify.value,
282                                             handler_obj->notify.context);
283         }
284
285         /* All done with the info object */
286
287         acpi_ut_delete_generic_state(notify_info);
288 }
289
290 /*******************************************************************************
291  *
292  * FUNCTION:    acpi_ev_global_lock_handler
293  *
294  * PARAMETERS:  Context         - From thread interface, not used
295  *
296  * RETURN:      ACPI_INTERRUPT_HANDLED
297  *
298  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
299  *              release interrupt occurs. Attempt to acquire the global lock,
300  *              if successful, signal the thread waiting for the lock.
301  *
302  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
303  * this is not possible for some reason, a separate thread will have to be
304  * scheduled to do this.
305  *
306  ******************************************************************************/
307
308 static u32 acpi_ev_global_lock_handler(void *context)
309 {
310         u8 acquired = FALSE;
311
312         /*
313          * Attempt to get the lock.
314          *
315          * If we don't get it now, it will be marked pending and we will
316          * take another interrupt when it becomes free.
317          */
318         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
319         if (acquired) {
320
321                 /* Got the lock, now wake all threads waiting for it */
322
323                 acpi_gbl_global_lock_acquired = TRUE;
324                 /* Send a unit to the semaphore */
325
326                 if (ACPI_FAILURE(acpi_os_signal_semaphore(
327                         acpi_gbl_global_lock_semaphore, 1))) {
328                         ACPI_ERROR((AE_INFO,
329                                     "Could not signal Global Lock semaphore"));
330                 }
331         }
332
333         return (ACPI_INTERRUPT_HANDLED);
334 }
335
336 /*******************************************************************************
337  *
338  * FUNCTION:    acpi_ev_init_global_lock_handler
339  *
340  * PARAMETERS:  None
341  *
342  * RETURN:      Status
343  *
344  * DESCRIPTION: Install a handler for the global lock release event
345  *
346  ******************************************************************************/
347
348 acpi_status acpi_ev_init_global_lock_handler(void)
349 {
350         acpi_status status;
351
352         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
353
354         status =
355             acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
356                                     (struct acpi_table_header **)&facs);
357         if (ACPI_FAILURE(status)) {
358                 return_ACPI_STATUS(status);
359         }
360
361         acpi_gbl_global_lock_present = TRUE;
362         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
363                                                   acpi_ev_global_lock_handler,
364                                                   NULL);
365
366         /*
367          * If the global lock does not exist on this platform, the attempt
368          * to enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick)
369          * Map to AE_OK, but mark global lock as not present.
370          * Any attempt to actually use the global lock will be flagged
371          * with an error.
372          */
373         if (status == AE_NO_HARDWARE_RESPONSE) {
374                 ACPI_ERROR((AE_INFO,
375                             "No response from Global Lock hardware, disabling lock"));
376
377                 acpi_gbl_global_lock_present = FALSE;
378                 status = AE_OK;
379         }
380
381         return_ACPI_STATUS(status);
382 }
383
384 /*******************************************************************************
385  *
386  * FUNCTION:    acpi_ev_remove_global_lock_handler
387  *
388  * PARAMETERS:  None
389  *
390  * RETURN:      Status
391  *
392  * DESCRIPTION: Remove the handler for the Global Lock
393  *
394  ******************************************************************************/
395
396 static acpi_status acpi_ev_remove_global_lock_handler(void)
397 {
398         acpi_status status;
399
400         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
401
402         acpi_gbl_global_lock_present = FALSE;
403         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
404                                                  acpi_ev_global_lock_handler);
405
406         return_ACPI_STATUS(status);
407 }
408
409 /******************************************************************************
410  *
411  * FUNCTION:    acpi_ev_acquire_global_lock
412  *
413  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
414  *
415  * RETURN:      Status
416  *
417  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
418  *
419  * MUTEX:       Interpreter must be locked
420  *
421  * Note: The original implementation allowed multiple threads to "acquire" the
422  * Global Lock, and the OS would hold the lock until the last thread had
423  * released it. However, this could potentially starve the BIOS out of the
424  * lock, especially in the case where there is a tight handshake between the
425  * Embedded Controller driver and the BIOS. Therefore, this implementation
426  * allows only one thread to acquire the HW Global Lock at a time, and makes
427  * the global lock appear as a standard mutex on the OS side.
428  *
429  *****************************************************************************/
430 static acpi_thread_id acpi_ev_global_lock_thread_id;
431 static int acpi_ev_global_lock_acquired;
432
433 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
434 {
435         acpi_status status = AE_OK;
436         u8 acquired = FALSE;
437
438         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
439
440         /*
441          * Only one thread can acquire the GL at a time, the global_lock_mutex
442          * enforces this. This interface releases the interpreter if we must wait.
443          */
444         status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, 0);
445         if (status == AE_TIME) {
446                 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
447                         acpi_ev_global_lock_acquired++;
448                         return AE_OK;
449                 }
450         }
451
452         if (ACPI_FAILURE(status)) {
453                 status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, timeout);
454         }
455         if (ACPI_FAILURE(status)) {
456                 return_ACPI_STATUS(status);
457         }
458
459         acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
460         acpi_ev_global_lock_acquired++;
461
462         /*
463          * Make sure that a global lock actually exists. If not, just treat
464          * the lock as a standard mutex.
465          */
466         if (!acpi_gbl_global_lock_present) {
467                 acpi_gbl_global_lock_acquired = TRUE;
468                 return_ACPI_STATUS(AE_OK);
469         }
470
471         /* Attempt to acquire the actual hardware lock */
472
473         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
474         if (acquired) {
475
476                 /* We got the lock */
477
478                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
479                                   "Acquired hardware Global Lock\n"));
480
481                 acpi_gbl_global_lock_acquired = TRUE;
482                 return_ACPI_STATUS(AE_OK);
483         }
484
485         /*
486          * Did not get the lock. The pending bit was set above, and we must now
487          * wait until we get the global lock released interrupt.
488          */
489         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n"));
490
491         /*
492          * Wait for handshake with the global lock interrupt handler.
493          * This interface releases the interpreter if we must wait.
494          */
495         status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore,
496                                                ACPI_WAIT_FOREVER);
497
498         return_ACPI_STATUS(status);
499 }
500
501 /*******************************************************************************
502  *
503  * FUNCTION:    acpi_ev_release_global_lock
504  *
505  * PARAMETERS:  None
506  *
507  * RETURN:      Status
508  *
509  * DESCRIPTION: Releases ownership of the Global Lock.
510  *
511  ******************************************************************************/
512
513 acpi_status acpi_ev_release_global_lock(void)
514 {
515         u8 pending = FALSE;
516         acpi_status status = AE_OK;
517
518         ACPI_FUNCTION_TRACE(ev_release_global_lock);
519
520         /* Lock must be already acquired */
521
522         if (!acpi_gbl_global_lock_acquired) {
523                 ACPI_WARNING((AE_INFO,
524                               "Cannot release the ACPI Global Lock, it has not been acquired"));
525                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
526         }
527
528         acpi_ev_global_lock_acquired--;
529         if (acpi_ev_global_lock_acquired > 0) {
530                 return AE_OK;
531         }
532
533         if (acpi_gbl_global_lock_present) {
534
535                 /* Allow any thread to release the lock */
536
537                 ACPI_RELEASE_GLOBAL_LOCK(facs, pending);
538
539                 /*
540                  * If the pending bit was set, we must write GBL_RLS to the control
541                  * register
542                  */
543                 if (pending) {
544                         status =
545                             acpi_set_register(ACPI_BITREG_GLOBAL_LOCK_RELEASE,
546                                               1);
547                 }
548
549                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
550                                   "Released hardware Global Lock\n"));
551         }
552
553         acpi_gbl_global_lock_acquired = FALSE;
554
555         /* Release the local GL mutex */
556         acpi_ev_global_lock_thread_id = NULL;
557         acpi_ev_global_lock_acquired = 0;
558         acpi_os_release_mutex(acpi_gbl_global_lock_mutex);
559         return_ACPI_STATUS(status);
560 }
561
562 /******************************************************************************
563  *
564  * FUNCTION:    acpi_ev_terminate
565  *
566  * PARAMETERS:  none
567  *
568  * RETURN:      none
569  *
570  * DESCRIPTION: Disable events and free memory allocated for table storage.
571  *
572  ******************************************************************************/
573
574 void acpi_ev_terminate(void)
575 {
576         acpi_native_uint i;
577         acpi_status status;
578
579         ACPI_FUNCTION_TRACE(ev_terminate);
580
581         if (acpi_gbl_events_initialized) {
582                 /*
583                  * Disable all event-related functionality.
584                  * In all cases, on error, print a message but obviously we don't abort.
585                  */
586
587                 /* Disable all fixed events */
588
589                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
590                         status = acpi_disable_event((u32) i, 0);
591                         if (ACPI_FAILURE(status)) {
592                                 ACPI_ERROR((AE_INFO,
593                                             "Could not disable fixed event %d",
594                                             (u32) i));
595                         }
596                 }
597
598                 /* Disable all GPEs in all GPE blocks */
599
600                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block);
601
602                 /* Remove SCI handler */
603
604                 status = acpi_ev_remove_sci_handler();
605                 if (ACPI_FAILURE(status)) {
606                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
607                 }
608
609                 status = acpi_ev_remove_global_lock_handler();
610                 if (ACPI_FAILURE(status)) {
611                         ACPI_ERROR((AE_INFO,
612                                     "Could not remove Global Lock handler"));
613                 }
614         }
615
616         /* Deallocate all handler objects installed within GPE info structs */
617
618         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers);
619
620         /* Return to original mode if necessary */
621
622         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
623                 status = acpi_disable();
624                 if (ACPI_FAILURE(status)) {
625                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
626                 }
627         }
628         return_VOID;
629 }