ACPICA: Remove global lock handler on AcpiTerminate.
[sfrench/cifs-2.6.git] / drivers / acpi / events / evmisc.c
1 /******************************************************************************
2  *
3  * Module Name: evmisc - Miscellaneous event manager support functions
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2006, 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                 status =
200                     acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_notify_dispatch,
201                                     notify_info);
202                 if (ACPI_FAILURE(status)) {
203                         acpi_ut_delete_generic_state(notify_info);
204                 }
205         }
206
207         if (!handler_obj) {
208                 /*
209                  * There is no per-device notify handler for this device.
210                  * This may or may not be a problem.
211                  */
212                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
213                                   "No notify handler for Notify(%4.4s, %X) node %p\n",
214                                   acpi_ut_get_node_name(node), notify_value,
215                                   node));
216         }
217
218         return (status);
219 }
220
221 /*******************************************************************************
222  *
223  * FUNCTION:    acpi_ev_notify_dispatch
224  *
225  * PARAMETERS:  Context         - To be passed to the notify handler
226  *
227  * RETURN:      None.
228  *
229  * DESCRIPTION: Dispatch a device notification event to a previously
230  *              installed handler.
231  *
232  ******************************************************************************/
233
234 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
235 {
236         union acpi_generic_state *notify_info =
237             (union acpi_generic_state *)context;
238         acpi_notify_handler global_handler = NULL;
239         void *global_context = NULL;
240         union acpi_operand_object *handler_obj;
241
242         ACPI_FUNCTION_ENTRY();
243
244         /*
245          * We will invoke a global notify handler if installed.
246          * This is done _before_ we invoke the per-device handler attached
247          * to the device.
248          */
249         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
250
251                 /* Global system notification handler */
252
253                 if (acpi_gbl_system_notify.handler) {
254                         global_handler = acpi_gbl_system_notify.handler;
255                         global_context = acpi_gbl_system_notify.context;
256                 }
257         } else {
258                 /* Global driver notification handler */
259
260                 if (acpi_gbl_device_notify.handler) {
261                         global_handler = acpi_gbl_device_notify.handler;
262                         global_context = acpi_gbl_device_notify.context;
263                 }
264         }
265
266         /* Invoke the system handler first, if present */
267
268         if (global_handler) {
269                 global_handler(notify_info->notify.node,
270                                notify_info->notify.value, global_context);
271         }
272
273         /* Now invoke the per-device handler, if present */
274
275         handler_obj = notify_info->notify.handler_obj;
276         if (handler_obj) {
277                 handler_obj->notify.handler(notify_info->notify.node,
278                                             notify_info->notify.value,
279                                             handler_obj->notify.context);
280         }
281
282         /* All done with the info object */
283
284         acpi_ut_delete_generic_state(notify_info);
285 }
286
287 /*******************************************************************************
288  *
289  * FUNCTION:    acpi_ev_global_lock_handler
290  *
291  * PARAMETERS:  Context         - From thread interface, not used
292  *
293  * RETURN:      ACPI_INTERRUPT_HANDLED
294  *
295  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
296  *              release interrupt occurs. Attempt to acquire the global lock,
297  *              if successful, signal the thread waiting for the lock.
298  *
299  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
300  * this is not possible for some reason, a separate thread will have to be
301  * scheduled to do this.
302  *
303  ******************************************************************************/
304
305 static u32 acpi_ev_global_lock_handler(void *context)
306 {
307         u8 acquired = FALSE;
308
309         /*
310          * Attempt to get the lock.
311          *
312          * If we don't get it now, it will be marked pending and we will
313          * take another interrupt when it becomes free.
314          */
315         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
316         if (acquired) {
317
318                 /* Got the lock, now wake all threads waiting for it */
319
320                 acpi_gbl_global_lock_acquired = TRUE;
321                 /* Send a unit to the semaphore */
322
323                 if (ACPI_FAILURE(acpi_os_signal_semaphore(
324                         acpi_gbl_global_lock_semaphore, 1))) {
325                         ACPI_ERROR((AE_INFO,
326                                     "Could not signal Global Lock semaphore"));
327                 }
328         }
329
330         return (ACPI_INTERRUPT_HANDLED);
331 }
332
333 /*******************************************************************************
334  *
335  * FUNCTION:    acpi_ev_init_global_lock_handler
336  *
337  * PARAMETERS:  None
338  *
339  * RETURN:      Status
340  *
341  * DESCRIPTION: Install a handler for the global lock release event
342  *
343  ******************************************************************************/
344
345 acpi_status acpi_ev_init_global_lock_handler(void)
346 {
347         acpi_status status;
348
349         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
350
351         status =
352             acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
353                                     (struct acpi_table_header **)&facs);
354         if (ACPI_FAILURE(status)) {
355                 return_ACPI_STATUS(status);
356         }
357
358         acpi_gbl_global_lock_present = TRUE;
359         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
360                                                   acpi_ev_global_lock_handler,
361                                                   NULL);
362
363         /*
364          * If the global lock does not exist on this platform, the attempt
365          * to enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick)
366          * Map to AE_OK, but mark global lock as not present.
367          * Any attempt to actually use the global lock will be flagged
368          * with an error.
369          */
370         if (status == AE_NO_HARDWARE_RESPONSE) {
371                 ACPI_ERROR((AE_INFO,
372                             "No response from Global Lock hardware, disabling lock"));
373
374                 acpi_gbl_global_lock_present = FALSE;
375                 status = AE_OK;
376         }
377
378         return_ACPI_STATUS(status);
379 }
380
381 /*******************************************************************************
382  *
383  * FUNCTION:    acpi_ev_remove_global_lock_handler
384  *
385  * PARAMETERS:  None
386  *
387  * RETURN:      Status
388  *
389  * DESCRIPTION: Remove the handler for the Global Lock
390  *
391  ******************************************************************************/
392
393 static acpi_status acpi_ev_remove_global_lock_handler(void)
394 {
395         acpi_status status;
396
397         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
398
399         acpi_gbl_global_lock_present = FALSE;
400         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
401                                                  acpi_ev_global_lock_handler);
402
403         return_ACPI_STATUS(status);
404 }
405
406 /******************************************************************************
407  *
408  * FUNCTION:    acpi_ev_acquire_global_lock
409  *
410  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
411  *
412  * RETURN:      Status
413  *
414  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
415  *
416  * MUTEX:       Interpreter must be locked
417  *
418  * Note: The original implementation allowed multiple threads to "acquire" the
419  * Global Lock, and the OS would hold the lock until the last thread had
420  * released it. However, this could potentially starve the BIOS out of the
421  * lock, especially in the case where there is a tight handshake between the
422  * Embedded Controller driver and the BIOS. Therefore, this implementation
423  * allows only one thread to acquire the HW Global Lock at a time, and makes
424  * the global lock appear as a standard mutex on the OS side.
425  *
426  *****************************************************************************/
427
428 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
429 {
430         acpi_status status = AE_OK;
431         u8 acquired = FALSE;
432
433         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
434
435         /*
436          * Only one thread can acquire the GL at a time, the global_lock_mutex
437          * enforces this. This interface releases the interpreter if we must wait.
438          */
439         status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, timeout);
440         if (ACPI_FAILURE(status)) {
441                 return_ACPI_STATUS(status);
442         }
443
444         /*
445          * Make sure that a global lock actually exists. If not, just treat
446          * the lock as a standard mutex.
447          */
448         if (!acpi_gbl_global_lock_present) {
449                 acpi_gbl_global_lock_acquired = TRUE;
450                 return_ACPI_STATUS(AE_OK);
451         }
452
453         /* Attempt to acquire the actual hardware lock */
454
455         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
456         if (acquired) {
457
458                 /* We got the lock */
459
460                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
461                                   "Acquired hardware Global Lock\n"));
462
463                 acpi_gbl_global_lock_acquired = TRUE;
464                 return_ACPI_STATUS(AE_OK);
465         }
466
467         /*
468          * Did not get the lock. The pending bit was set above, and we must now
469          * wait until we get the global lock released interrupt.
470          */
471         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n"));
472
473         /*
474          * Wait for handshake with the global lock interrupt handler.
475          * This interface releases the interpreter if we must wait.
476          */
477         status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore,
478                                                ACPI_WAIT_FOREVER);
479
480         return_ACPI_STATUS(status);
481 }
482
483 /*******************************************************************************
484  *
485  * FUNCTION:    acpi_ev_release_global_lock
486  *
487  * PARAMETERS:  None
488  *
489  * RETURN:      Status
490  *
491  * DESCRIPTION: Releases ownership of the Global Lock.
492  *
493  ******************************************************************************/
494
495 acpi_status acpi_ev_release_global_lock(void)
496 {
497         u8 pending = FALSE;
498         acpi_status status = AE_OK;
499
500         ACPI_FUNCTION_TRACE(ev_release_global_lock);
501
502         /* Lock must be already acquired */
503
504         if (!acpi_gbl_global_lock_acquired) {
505                 ACPI_WARNING((AE_INFO,
506                               "Cannot release the ACPI Global Lock, it has not been acquired"));
507                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
508         }
509
510         if (acpi_gbl_global_lock_present) {
511
512                 /* Allow any thread to release the lock */
513
514                 ACPI_RELEASE_GLOBAL_LOCK(facs, pending);
515
516                 /*
517                  * If the pending bit was set, we must write GBL_RLS to the control
518                  * register
519                  */
520                 if (pending) {
521                         status =
522                             acpi_set_register(ACPI_BITREG_GLOBAL_LOCK_RELEASE,
523                                               1);
524                 }
525
526                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
527                                   "Released hardware Global Lock\n"));
528         }
529
530         acpi_gbl_global_lock_acquired = FALSE;
531
532         /* Release the local GL mutex */
533
534         acpi_os_release_mutex(acpi_gbl_global_lock_mutex);
535         return_ACPI_STATUS(status);
536 }
537
538 /******************************************************************************
539  *
540  * FUNCTION:    acpi_ev_terminate
541  *
542  * PARAMETERS:  none
543  *
544  * RETURN:      none
545  *
546  * DESCRIPTION: Disable events and free memory allocated for table storage.
547  *
548  ******************************************************************************/
549
550 void acpi_ev_terminate(void)
551 {
552         acpi_native_uint i;
553         acpi_status status;
554
555         ACPI_FUNCTION_TRACE(ev_terminate);
556
557         if (acpi_gbl_events_initialized) {
558                 /*
559                  * Disable all event-related functionality.
560                  * In all cases, on error, print a message but obviously we don't abort.
561                  */
562
563                 /* Disable all fixed events */
564
565                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
566                         status = acpi_disable_event((u32) i, 0);
567                         if (ACPI_FAILURE(status)) {
568                                 ACPI_ERROR((AE_INFO,
569                                             "Could not disable fixed event %d",
570                                             (u32) i));
571                         }
572                 }
573
574                 /* Disable all GPEs in all GPE blocks */
575
576                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block);
577
578                 /* Remove SCI handler */
579
580                 status = acpi_ev_remove_sci_handler();
581                 if (ACPI_FAILURE(status)) {
582                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
583                 }
584
585                 status = acpi_ev_remove_global_lock_handler();
586                 if (ACPI_FAILURE(status)) {
587                         ACPI_ERROR((AE_INFO,
588                                     "Could not remove Global Lock handler"));
589                 }
590         }
591
592         /* Deallocate all handler objects installed within GPE info structs */
593
594         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers);
595
596         /* Return to original mode if necessary */
597
598         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
599                 status = acpi_disable();
600                 if (ACPI_FAILURE(status)) {
601                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
602                 }
603         }
604         return_VOID;
605 }