Merge git://git.kernel.org/pub/scm/linux/kernel/git/joern/misc
[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_relinquish_interpreter();
200
201                 acpi_ev_notify_dispatch(notify_info);
202
203                 acpi_ex_reacquire_interpreter();
204         }
205
206         if (!handler_obj) {
207                 /*
208                  * There is no per-device notify handler for this device.
209                  * This may or may not be a problem.
210                  */
211                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
212                                   "No notify handler for Notify(%4.4s, %X) node %p\n",
213                                   acpi_ut_get_node_name(node), notify_value,
214                                   node));
215         }
216
217         return (status);
218 }
219
220 /*******************************************************************************
221  *
222  * FUNCTION:    acpi_ev_notify_dispatch
223  *
224  * PARAMETERS:  Context         - To be passed to the notify handler
225  *
226  * RETURN:      None.
227  *
228  * DESCRIPTION: Dispatch a device notification event to a previously
229  *              installed handler.
230  *
231  ******************************************************************************/
232
233 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
234 {
235         union acpi_generic_state *notify_info =
236             (union acpi_generic_state *)context;
237         acpi_notify_handler global_handler = NULL;
238         void *global_context = NULL;
239         union acpi_operand_object *handler_obj;
240
241         ACPI_FUNCTION_ENTRY();
242
243         /*
244          * We will invoke a global notify handler if installed.
245          * This is done _before_ we invoke the per-device handler attached
246          * to the device.
247          */
248         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
249
250                 /* Global system notification handler */
251
252                 if (acpi_gbl_system_notify.handler) {
253                         global_handler = acpi_gbl_system_notify.handler;
254                         global_context = acpi_gbl_system_notify.context;
255                 }
256         } else {
257                 /* Global driver notification handler */
258
259                 if (acpi_gbl_device_notify.handler) {
260                         global_handler = acpi_gbl_device_notify.handler;
261                         global_context = acpi_gbl_device_notify.context;
262                 }
263         }
264
265         /* Invoke the system handler first, if present */
266
267         if (global_handler) {
268                 global_handler(notify_info->notify.node,
269                                notify_info->notify.value, global_context);
270         }
271
272         /* Now invoke the per-device handler, if present */
273
274         handler_obj = notify_info->notify.handler_obj;
275         if (handler_obj) {
276                 handler_obj->notify.handler(notify_info->notify.node,
277                                             notify_info->notify.value,
278                                             handler_obj->notify.context);
279         }
280
281         /* All done with the info object */
282
283         acpi_ut_delete_generic_state(notify_info);
284 }
285
286 /*******************************************************************************
287  *
288  * FUNCTION:    acpi_ev_global_lock_handler
289  *
290  * PARAMETERS:  Context         - From thread interface, not used
291  *
292  * RETURN:      ACPI_INTERRUPT_HANDLED
293  *
294  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
295  *              release interrupt occurs. Attempt to acquire the global lock,
296  *              if successful, signal the thread waiting for the lock.
297  *
298  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
299  * this is not possible for some reason, a separate thread will have to be
300  * scheduled to do this.
301  *
302  ******************************************************************************/
303
304 static u32 acpi_ev_global_lock_handler(void *context)
305 {
306         u8 acquired = FALSE;
307
308         /*
309          * Attempt to get the lock.
310          *
311          * If we don't get it now, it will be marked pending and we will
312          * take another interrupt when it becomes free.
313          */
314         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
315         if (acquired) {
316
317                 /* Got the lock, now wake all threads waiting for it */
318
319                 acpi_gbl_global_lock_acquired = TRUE;
320                 /* Send a unit to the semaphore */
321
322                 if (ACPI_FAILURE(acpi_os_signal_semaphore(
323                         acpi_gbl_global_lock_semaphore, 1))) {
324                         ACPI_ERROR((AE_INFO,
325                                     "Could not signal Global Lock semaphore"));
326                 }
327         }
328
329         return (ACPI_INTERRUPT_HANDLED);
330 }
331
332 /*******************************************************************************
333  *
334  * FUNCTION:    acpi_ev_init_global_lock_handler
335  *
336  * PARAMETERS:  None
337  *
338  * RETURN:      Status
339  *
340  * DESCRIPTION: Install a handler for the global lock release event
341  *
342  ******************************************************************************/
343
344 acpi_status acpi_ev_init_global_lock_handler(void)
345 {
346         acpi_status status;
347
348         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
349
350         status =
351             acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
352                                     (struct acpi_table_header **)&facs);
353         if (ACPI_FAILURE(status)) {
354                 return_ACPI_STATUS(status);
355         }
356
357         acpi_gbl_global_lock_present = TRUE;
358         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
359                                                   acpi_ev_global_lock_handler,
360                                                   NULL);
361
362         /*
363          * If the global lock does not exist on this platform, the attempt
364          * to enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick)
365          * Map to AE_OK, but mark global lock as not present.
366          * Any attempt to actually use the global lock will be flagged
367          * with an error.
368          */
369         if (status == AE_NO_HARDWARE_RESPONSE) {
370                 ACPI_ERROR((AE_INFO,
371                             "No response from Global Lock hardware, disabling lock"));
372
373                 acpi_gbl_global_lock_present = FALSE;
374                 status = AE_OK;
375         }
376
377         return_ACPI_STATUS(status);
378 }
379
380 /*******************************************************************************
381  *
382  * FUNCTION:    acpi_ev_remove_global_lock_handler
383  *
384  * PARAMETERS:  None
385  *
386  * RETURN:      Status
387  *
388  * DESCRIPTION: Remove the handler for the Global Lock
389  *
390  ******************************************************************************/
391
392 static acpi_status acpi_ev_remove_global_lock_handler(void)
393 {
394         acpi_status status;
395
396         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
397
398         acpi_gbl_global_lock_present = FALSE;
399         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
400                                                  acpi_ev_global_lock_handler);
401
402         return_ACPI_STATUS(status);
403 }
404
405 /******************************************************************************
406  *
407  * FUNCTION:    acpi_ev_acquire_global_lock
408  *
409  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
410  *
411  * RETURN:      Status
412  *
413  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
414  *
415  * MUTEX:       Interpreter must be locked
416  *
417  * Note: The original implementation allowed multiple threads to "acquire" the
418  * Global Lock, and the OS would hold the lock until the last thread had
419  * released it. However, this could potentially starve the BIOS out of the
420  * lock, especially in the case where there is a tight handshake between the
421  * Embedded Controller driver and the BIOS. Therefore, this implementation
422  * allows only one thread to acquire the HW Global Lock at a time, and makes
423  * the global lock appear as a standard mutex on the OS side.
424  *
425  *****************************************************************************/
426 static acpi_thread_id acpi_ev_global_lock_thread_id;
427 static int acpi_ev_global_lock_acquired;
428
429 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
430 {
431         acpi_status status = AE_OK;
432         u8 acquired = FALSE;
433
434         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
435
436         /*
437          * Only one thread can acquire the GL at a time, the global_lock_mutex
438          * enforces this. This interface releases the interpreter if we must wait.
439          */
440         status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, 0);
441         if (status == AE_TIME) {
442                 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
443                         acpi_ev_global_lock_acquired++;
444                         return AE_OK;
445                 }
446         }
447
448         if (ACPI_FAILURE(status)) {
449                 status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, timeout);
450         }
451         if (ACPI_FAILURE(status)) {
452                 return_ACPI_STATUS(status);
453         }
454
455         acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
456         acpi_ev_global_lock_acquired++;
457
458         /*
459          * Make sure that a global lock actually exists. If not, just treat
460          * the lock as a standard mutex.
461          */
462         if (!acpi_gbl_global_lock_present) {
463                 acpi_gbl_global_lock_acquired = TRUE;
464                 return_ACPI_STATUS(AE_OK);
465         }
466
467         /* Attempt to acquire the actual hardware lock */
468
469         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
470         if (acquired) {
471
472                 /* We got the lock */
473
474                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
475                                   "Acquired hardware Global Lock\n"));
476
477                 acpi_gbl_global_lock_acquired = TRUE;
478                 return_ACPI_STATUS(AE_OK);
479         }
480
481         /*
482          * Did not get the lock. The pending bit was set above, and we must now
483          * wait until we get the global lock released interrupt.
484          */
485         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n"));
486
487         /*
488          * Wait for handshake with the global lock interrupt handler.
489          * This interface releases the interpreter if we must wait.
490          */
491         status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore,
492                                                ACPI_WAIT_FOREVER);
493
494         return_ACPI_STATUS(status);
495 }
496
497 /*******************************************************************************
498  *
499  * FUNCTION:    acpi_ev_release_global_lock
500  *
501  * PARAMETERS:  None
502  *
503  * RETURN:      Status
504  *
505  * DESCRIPTION: Releases ownership of the Global Lock.
506  *
507  ******************************************************************************/
508
509 acpi_status acpi_ev_release_global_lock(void)
510 {
511         u8 pending = FALSE;
512         acpi_status status = AE_OK;
513
514         ACPI_FUNCTION_TRACE(ev_release_global_lock);
515
516         /* Lock must be already acquired */
517
518         if (!acpi_gbl_global_lock_acquired) {
519                 ACPI_WARNING((AE_INFO,
520                               "Cannot release the ACPI Global Lock, it has not been acquired"));
521                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
522         }
523
524         acpi_ev_global_lock_acquired--;
525         if (acpi_ev_global_lock_acquired > 0) {
526                 return AE_OK;
527         }
528
529         if (acpi_gbl_global_lock_present) {
530
531                 /* Allow any thread to release the lock */
532
533                 ACPI_RELEASE_GLOBAL_LOCK(facs, pending);
534
535                 /*
536                  * If the pending bit was set, we must write GBL_RLS to the control
537                  * register
538                  */
539                 if (pending) {
540                         status =
541                             acpi_set_register(ACPI_BITREG_GLOBAL_LOCK_RELEASE,
542                                               1);
543                 }
544
545                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
546                                   "Released hardware Global Lock\n"));
547         }
548
549         acpi_gbl_global_lock_acquired = FALSE;
550
551         /* Release the local GL mutex */
552         acpi_ev_global_lock_thread_id = 0;
553         acpi_ev_global_lock_acquired = 0;
554         acpi_os_release_mutex(acpi_gbl_global_lock_mutex);
555         return_ACPI_STATUS(status);
556 }
557
558 /******************************************************************************
559  *
560  * FUNCTION:    acpi_ev_terminate
561  *
562  * PARAMETERS:  none
563  *
564  * RETURN:      none
565  *
566  * DESCRIPTION: Disable events and free memory allocated for table storage.
567  *
568  ******************************************************************************/
569
570 void acpi_ev_terminate(void)
571 {
572         acpi_native_uint i;
573         acpi_status status;
574
575         ACPI_FUNCTION_TRACE(ev_terminate);
576
577         if (acpi_gbl_events_initialized) {
578                 /*
579                  * Disable all event-related functionality.
580                  * In all cases, on error, print a message but obviously we don't abort.
581                  */
582
583                 /* Disable all fixed events */
584
585                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
586                         status = acpi_disable_event((u32) i, 0);
587                         if (ACPI_FAILURE(status)) {
588                                 ACPI_ERROR((AE_INFO,
589                                             "Could not disable fixed event %d",
590                                             (u32) i));
591                         }
592                 }
593
594                 /* Disable all GPEs in all GPE blocks */
595
596                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block);
597
598                 /* Remove SCI handler */
599
600                 status = acpi_ev_remove_sci_handler();
601                 if (ACPI_FAILURE(status)) {
602                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
603                 }
604
605                 status = acpi_ev_remove_global_lock_handler();
606                 if (ACPI_FAILURE(status)) {
607                         ACPI_ERROR((AE_INFO,
608                                     "Could not remove Global Lock handler"));
609                 }
610         }
611
612         /* Deallocate all handler objects installed within GPE info structs */
613
614         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers);
615
616         /* Return to original mode if necessary */
617
618         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
619                 status = acpi_disable();
620                 if (ACPI_FAILURE(status)) {
621                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
622                 }
623         }
624         return_VOID;
625 }