ACPICA: Add error checks to prevent faults
[linux-2.6] / drivers / acpi / events / evgpeblk.c
1 /******************************************************************************
2  *
3  * Module Name: evgpeblk - GPE block creation and initialization.
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
48 #define _COMPONENT          ACPI_EVENTS
49 ACPI_MODULE_NAME("evgpeblk")
50
51 /* Local prototypes */
52 static acpi_status
53 acpi_ev_save_method_info(acpi_handle obj_handle,
54                          u32 level, void *obj_desc, void **return_value);
55
56 static acpi_status
57 acpi_ev_match_prw_and_gpe(acpi_handle obj_handle,
58                           u32 level, void *info, void **return_value);
59
60 static struct acpi_gpe_xrupt_info *acpi_ev_get_gpe_xrupt_block(u32
61                                                                interrupt_number);
62
63 static acpi_status
64 acpi_ev_delete_gpe_xrupt(struct acpi_gpe_xrupt_info *gpe_xrupt);
65
66 static acpi_status
67 acpi_ev_install_gpe_block(struct acpi_gpe_block_info *gpe_block,
68                           u32 interrupt_number);
69
70 static acpi_status
71 acpi_ev_create_gpe_info_blocks(struct acpi_gpe_block_info *gpe_block);
72
73 /*******************************************************************************
74  *
75  * FUNCTION:    acpi_ev_valid_gpe_event
76  *
77  * PARAMETERS:  gpe_event_info              - Info for this GPE
78  *
79  * RETURN:      TRUE if the gpe_event is valid
80  *
81  * DESCRIPTION: Validate a GPE event. DO NOT CALL FROM INTERRUPT LEVEL.
82  *              Should be called only when the GPE lists are semaphore locked
83  *              and not subject to change.
84  *
85  ******************************************************************************/
86
87 u8 acpi_ev_valid_gpe_event(struct acpi_gpe_event_info *gpe_event_info)
88 {
89         struct acpi_gpe_xrupt_info *gpe_xrupt_block;
90         struct acpi_gpe_block_info *gpe_block;
91
92         ACPI_FUNCTION_ENTRY();
93
94         /* No need for spin lock since we are not changing any list elements */
95
96         /* Walk the GPE interrupt levels */
97
98         gpe_xrupt_block = acpi_gbl_gpe_xrupt_list_head;
99         while (gpe_xrupt_block) {
100                 gpe_block = gpe_xrupt_block->gpe_block_list_head;
101
102                 /* Walk the GPE blocks on this interrupt level */
103
104                 while (gpe_block) {
105                         if ((&gpe_block->event_info[0] <= gpe_event_info) &&
106                             (&gpe_block->
107                              event_info[((acpi_size) gpe_block->
108                                          register_count) * 8] >
109                              gpe_event_info)) {
110                                 return (TRUE);
111                         }
112
113                         gpe_block = gpe_block->next;
114                 }
115
116                 gpe_xrupt_block = gpe_xrupt_block->next;
117         }
118
119         return (FALSE);
120 }
121
122 /*******************************************************************************
123  *
124  * FUNCTION:    acpi_ev_walk_gpe_list
125  *
126  * PARAMETERS:  gpe_walk_callback   - Routine called for each GPE block
127  *
128  * RETURN:      Status
129  *
130  * DESCRIPTION: Walk the GPE lists.
131  *
132  ******************************************************************************/
133
134 acpi_status acpi_ev_walk_gpe_list(acpi_gpe_callback gpe_walk_callback)
135 {
136         struct acpi_gpe_block_info *gpe_block;
137         struct acpi_gpe_xrupt_info *gpe_xrupt_info;
138         acpi_status status = AE_OK;
139         acpi_cpu_flags flags;
140
141         ACPI_FUNCTION_TRACE(ev_walk_gpe_list);
142
143         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
144
145         /* Walk the interrupt level descriptor list */
146
147         gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
148         while (gpe_xrupt_info) {
149
150                 /* Walk all Gpe Blocks attached to this interrupt level */
151
152                 gpe_block = gpe_xrupt_info->gpe_block_list_head;
153                 while (gpe_block) {
154
155                         /* One callback per GPE block */
156
157                         status = gpe_walk_callback(gpe_xrupt_info, gpe_block);
158                         if (ACPI_FAILURE(status)) {
159                                 goto unlock_and_exit;
160                         }
161
162                         gpe_block = gpe_block->next;
163                 }
164
165                 gpe_xrupt_info = gpe_xrupt_info->next;
166         }
167
168       unlock_and_exit:
169         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
170         return_ACPI_STATUS(status);
171 }
172
173 /*******************************************************************************
174  *
175  * FUNCTION:    acpi_ev_delete_gpe_handlers
176  *
177  * PARAMETERS:  gpe_xrupt_info      - GPE Interrupt info
178  *              gpe_block           - Gpe Block info
179  *
180  * RETURN:      Status
181  *
182  * DESCRIPTION: Delete all Handler objects found in the GPE data structs.
183  *              Used only prior to termination.
184  *
185  ******************************************************************************/
186
187 acpi_status
188 acpi_ev_delete_gpe_handlers(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
189                             struct acpi_gpe_block_info *gpe_block)
190 {
191         struct acpi_gpe_event_info *gpe_event_info;
192         acpi_native_uint i;
193         acpi_native_uint j;
194
195         ACPI_FUNCTION_TRACE(ev_delete_gpe_handlers);
196
197         /* Examine each GPE Register within the block */
198
199         for (i = 0; i < gpe_block->register_count; i++) {
200
201                 /* Now look at the individual GPEs in this byte register */
202
203                 for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
204                         gpe_event_info =
205                             &gpe_block->
206                             event_info[(i * ACPI_GPE_REGISTER_WIDTH) + j];
207
208                         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
209                             ACPI_GPE_DISPATCH_HANDLER) {
210                                 ACPI_FREE(gpe_event_info->dispatch.handler);
211                                 gpe_event_info->dispatch.handler = NULL;
212                                 gpe_event_info->flags &=
213                                     ~ACPI_GPE_DISPATCH_MASK;
214                         }
215                 }
216         }
217
218         return_ACPI_STATUS(AE_OK);
219 }
220
221 /*******************************************************************************
222  *
223  * FUNCTION:    acpi_ev_save_method_info
224  *
225  * PARAMETERS:  Callback from walk_namespace
226  *
227  * RETURN:      Status
228  *
229  * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
230  *              control method under the _GPE portion of the namespace.
231  *              Extract the name and GPE type from the object, saving this
232  *              information for quick lookup during GPE dispatch
233  *
234  *              The name of each GPE control method is of the form:
235  *              "_Lxx" or "_Exx"
236  *              Where:
237  *                  L      - means that the GPE is level triggered
238  *                  E      - means that the GPE is edge triggered
239  *                  xx     - is the GPE number [in HEX]
240  *
241  ******************************************************************************/
242
243 static acpi_status
244 acpi_ev_save_method_info(acpi_handle obj_handle,
245                          u32 level, void *obj_desc, void **return_value)
246 {
247         struct acpi_gpe_block_info *gpe_block = (void *)obj_desc;
248         struct acpi_gpe_event_info *gpe_event_info;
249         u32 gpe_number;
250         char name[ACPI_NAME_SIZE + 1];
251         u8 type;
252         acpi_status status;
253
254         ACPI_FUNCTION_TRACE(ev_save_method_info);
255
256         /*
257          * _Lxx and _Exx GPE method support
258          *
259          * 1) Extract the name from the object and convert to a string
260          */
261         ACPI_MOVE_32_TO_32(name,
262                            &((struct acpi_namespace_node *)obj_handle)->name.
263                            integer);
264         name[ACPI_NAME_SIZE] = 0;
265
266         /*
267          * 2) Edge/Level determination is based on the 2nd character
268          *    of the method name
269          *
270          * NOTE: Default GPE type is RUNTIME. May be changed later to WAKE
271          * if a _PRW object is found that points to this GPE.
272          */
273         switch (name[1]) {
274         case 'L':
275                 type = ACPI_GPE_LEVEL_TRIGGERED;
276                 break;
277
278         case 'E':
279                 type = ACPI_GPE_EDGE_TRIGGERED;
280                 break;
281
282         default:
283                 /* Unknown method type, just ignore it! */
284
285                 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
286                                   "Ignoring unknown GPE method type: %s (name not of form _Lxx or _Exx)",
287                                   name));
288                 return_ACPI_STATUS(AE_OK);
289         }
290
291         /* Convert the last two characters of the name to the GPE Number */
292
293         gpe_number = ACPI_STRTOUL(&name[2], NULL, 16);
294         if (gpe_number == ACPI_UINT32_MAX) {
295
296                 /* Conversion failed; invalid method, just ignore it */
297
298                 ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
299                                   "Could not extract GPE number from name: %s (name is not of form _Lxx or _Exx)",
300                                   name));
301                 return_ACPI_STATUS(AE_OK);
302         }
303
304         /* Ensure that we have a valid GPE number for this GPE block */
305
306         if ((gpe_number < gpe_block->block_base_number) ||
307             (gpe_number >=
308              (gpe_block->block_base_number +
309               (gpe_block->register_count * 8)))) {
310                 /*
311                  * Not valid for this GPE block, just ignore it
312                  * However, it may be valid for a different GPE block, since GPE0 and GPE1
313                  * methods both appear under \_GPE.
314                  */
315                 return_ACPI_STATUS(AE_OK);
316         }
317
318         /*
319          * Now we can add this information to the gpe_event_info block
320          * for use during dispatch of this GPE. Default type is RUNTIME, although
321          * this may change when the _PRW methods are executed later.
322          */
323         gpe_event_info =
324             &gpe_block->event_info[gpe_number - gpe_block->block_base_number];
325
326         gpe_event_info->flags = (u8)
327             (type | ACPI_GPE_DISPATCH_METHOD | ACPI_GPE_TYPE_RUNTIME);
328
329         gpe_event_info->dispatch.method_node =
330             (struct acpi_namespace_node *)obj_handle;
331
332         /* Update enable mask, but don't enable the HW GPE as of yet */
333
334         status = acpi_ev_enable_gpe(gpe_event_info, FALSE);
335
336         ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
337                           "Registered GPE method %s as GPE number 0x%.2X\n",
338                           name, gpe_number));
339         return_ACPI_STATUS(status);
340 }
341
342 /*******************************************************************************
343  *
344  * FUNCTION:    acpi_ev_match_prw_and_gpe
345  *
346  * PARAMETERS:  Callback from walk_namespace
347  *
348  * RETURN:      Status. NOTE: We ignore errors so that the _PRW walk is
349  *              not aborted on a single _PRW failure.
350  *
351  * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
352  *              Device. Run the _PRW method. If present, extract the GPE
353  *              number and mark the GPE as a WAKE GPE.
354  *
355  ******************************************************************************/
356
357 static acpi_status
358 acpi_ev_match_prw_and_gpe(acpi_handle obj_handle,
359                           u32 level, void *info, void **return_value)
360 {
361         struct acpi_gpe_walk_info *gpe_info = (void *)info;
362         struct acpi_namespace_node *gpe_device;
363         struct acpi_gpe_block_info *gpe_block;
364         struct acpi_namespace_node *target_gpe_device;
365         struct acpi_gpe_event_info *gpe_event_info;
366         union acpi_operand_object *pkg_desc;
367         union acpi_operand_object *obj_desc;
368         u32 gpe_number;
369         acpi_status status;
370
371         ACPI_FUNCTION_TRACE(ev_match_prw_and_gpe);
372
373         /* Check for a _PRW method under this device */
374
375         status = acpi_ut_evaluate_object(obj_handle, METHOD_NAME__PRW,
376                                          ACPI_BTYPE_PACKAGE, &pkg_desc);
377         if (ACPI_FAILURE(status)) {
378
379                 /* Ignore all errors from _PRW, we don't want to abort the subsystem */
380
381                 return_ACPI_STATUS(AE_OK);
382         }
383
384         /* The returned _PRW package must have at least two elements */
385
386         if (pkg_desc->package.count < 2) {
387                 goto cleanup;
388         }
389
390         /* Extract pointers from the input context */
391
392         gpe_device = gpe_info->gpe_device;
393         gpe_block = gpe_info->gpe_block;
394
395         /*
396          * The _PRW object must return a package, we are only interested
397          * in the first element
398          */
399         obj_desc = pkg_desc->package.elements[0];
400
401         if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_INTEGER) {
402
403                 /* Use FADT-defined GPE device (from definition of _PRW) */
404
405                 target_gpe_device = acpi_gbl_fadt_gpe_device;
406
407                 /* Integer is the GPE number in the FADT described GPE blocks */
408
409                 gpe_number = (u32) obj_desc->integer.value;
410         } else if (ACPI_GET_OBJECT_TYPE(obj_desc) == ACPI_TYPE_PACKAGE) {
411
412                 /* Package contains a GPE reference and GPE number within a GPE block */
413
414                 if ((obj_desc->package.count < 2) ||
415                     (ACPI_GET_OBJECT_TYPE(obj_desc->package.elements[0]) !=
416                      ACPI_TYPE_LOCAL_REFERENCE)
417                     || (ACPI_GET_OBJECT_TYPE(obj_desc->package.elements[1]) !=
418                         ACPI_TYPE_INTEGER)) {
419                         goto cleanup;
420                 }
421
422                 /* Get GPE block reference and decode */
423
424                 target_gpe_device =
425                     obj_desc->package.elements[0]->reference.node;
426                 gpe_number = (u32) obj_desc->package.elements[1]->integer.value;
427         } else {
428                 /* Unknown type, just ignore it */
429
430                 goto cleanup;
431         }
432
433         /*
434          * Is this GPE within this block?
435          *
436          * TRUE iff these conditions are true:
437          *     1) The GPE devices match.
438          *     2) The GPE index(number) is within the range of the Gpe Block
439          *          associated with the GPE device.
440          */
441         if ((gpe_device == target_gpe_device) &&
442             (gpe_number >= gpe_block->block_base_number) &&
443             (gpe_number <
444              gpe_block->block_base_number + (gpe_block->register_count * 8))) {
445                 gpe_event_info =
446                     &gpe_block->event_info[gpe_number -
447                                            gpe_block->block_base_number];
448
449                 /* Mark GPE for WAKE-ONLY but WAKE_DISABLED */
450
451                 gpe_event_info->flags &=
452                     ~(ACPI_GPE_WAKE_ENABLED | ACPI_GPE_RUN_ENABLED);
453
454                 status =
455                     acpi_ev_set_gpe_type(gpe_event_info, ACPI_GPE_TYPE_WAKE);
456                 if (ACPI_FAILURE(status)) {
457                         goto cleanup;
458                 }
459                 status =
460                     acpi_ev_update_gpe_enable_masks(gpe_event_info,
461                                                     ACPI_GPE_DISABLE);
462         }
463
464       cleanup:
465         acpi_ut_remove_reference(pkg_desc);
466         return_ACPI_STATUS(AE_OK);
467 }
468
469 /*******************************************************************************
470  *
471  * FUNCTION:    acpi_ev_get_gpe_xrupt_block
472  *
473  * PARAMETERS:  interrupt_number     - Interrupt for a GPE block
474  *
475  * RETURN:      A GPE interrupt block
476  *
477  * DESCRIPTION: Get or Create a GPE interrupt block. There is one interrupt
478  *              block per unique interrupt level used for GPEs.
479  *              Should be called only when the GPE lists are semaphore locked
480  *              and not subject to change.
481  *
482  ******************************************************************************/
483
484 static struct acpi_gpe_xrupt_info *acpi_ev_get_gpe_xrupt_block(u32
485                                                                interrupt_number)
486 {
487         struct acpi_gpe_xrupt_info *next_gpe_xrupt;
488         struct acpi_gpe_xrupt_info *gpe_xrupt;
489         acpi_status status;
490         acpi_cpu_flags flags;
491
492         ACPI_FUNCTION_TRACE(ev_get_gpe_xrupt_block);
493
494         /* No need for lock since we are not changing any list elements here */
495
496         next_gpe_xrupt = acpi_gbl_gpe_xrupt_list_head;
497         while (next_gpe_xrupt) {
498                 if (next_gpe_xrupt->interrupt_number == interrupt_number) {
499                         return_PTR(next_gpe_xrupt);
500                 }
501
502                 next_gpe_xrupt = next_gpe_xrupt->next;
503         }
504
505         /* Not found, must allocate a new xrupt descriptor */
506
507         gpe_xrupt = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_xrupt_info));
508         if (!gpe_xrupt) {
509                 return_PTR(NULL);
510         }
511
512         gpe_xrupt->interrupt_number = interrupt_number;
513
514         /* Install new interrupt descriptor with spin lock */
515
516         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
517         if (acpi_gbl_gpe_xrupt_list_head) {
518                 next_gpe_xrupt = acpi_gbl_gpe_xrupt_list_head;
519                 while (next_gpe_xrupt->next) {
520                         next_gpe_xrupt = next_gpe_xrupt->next;
521                 }
522
523                 next_gpe_xrupt->next = gpe_xrupt;
524                 gpe_xrupt->previous = next_gpe_xrupt;
525         } else {
526                 acpi_gbl_gpe_xrupt_list_head = gpe_xrupt;
527         }
528         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
529
530         /* Install new interrupt handler if not SCI_INT */
531
532         if (interrupt_number != acpi_gbl_FADT.sci_interrupt) {
533                 status = acpi_os_install_interrupt_handler(interrupt_number,
534                                                            acpi_ev_gpe_xrupt_handler,
535                                                            gpe_xrupt);
536                 if (ACPI_FAILURE(status)) {
537                         ACPI_ERROR((AE_INFO,
538                                     "Could not install GPE interrupt handler at level 0x%X",
539                                     interrupt_number));
540                         return_PTR(NULL);
541                 }
542         }
543
544         return_PTR(gpe_xrupt);
545 }
546
547 /*******************************************************************************
548  *
549  * FUNCTION:    acpi_ev_delete_gpe_xrupt
550  *
551  * PARAMETERS:  gpe_xrupt       - A GPE interrupt info block
552  *
553  * RETURN:      Status
554  *
555  * DESCRIPTION: Remove and free a gpe_xrupt block. Remove an associated
556  *              interrupt handler if not the SCI interrupt.
557  *
558  ******************************************************************************/
559
560 static acpi_status
561 acpi_ev_delete_gpe_xrupt(struct acpi_gpe_xrupt_info *gpe_xrupt)
562 {
563         acpi_status status;
564         acpi_cpu_flags flags;
565
566         ACPI_FUNCTION_TRACE(ev_delete_gpe_xrupt);
567
568         /* We never want to remove the SCI interrupt handler */
569
570         if (gpe_xrupt->interrupt_number == acpi_gbl_FADT.sci_interrupt) {
571                 gpe_xrupt->gpe_block_list_head = NULL;
572                 return_ACPI_STATUS(AE_OK);
573         }
574
575         /* Disable this interrupt */
576
577         status =
578             acpi_os_remove_interrupt_handler(gpe_xrupt->interrupt_number,
579                                              acpi_ev_gpe_xrupt_handler);
580         if (ACPI_FAILURE(status)) {
581                 return_ACPI_STATUS(status);
582         }
583
584         /* Unlink the interrupt block with lock */
585
586         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
587         if (gpe_xrupt->previous) {
588                 gpe_xrupt->previous->next = gpe_xrupt->next;
589         } else {
590                 /* No previous, update list head */
591
592                 acpi_gbl_gpe_xrupt_list_head = gpe_xrupt->next;
593         }
594
595         if (gpe_xrupt->next) {
596                 gpe_xrupt->next->previous = gpe_xrupt->previous;
597         }
598         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
599
600         /* Free the block */
601
602         ACPI_FREE(gpe_xrupt);
603         return_ACPI_STATUS(AE_OK);
604 }
605
606 /*******************************************************************************
607  *
608  * FUNCTION:    acpi_ev_install_gpe_block
609  *
610  * PARAMETERS:  gpe_block       - New GPE block
611  *              interrupt_number - Xrupt to be associated with this GPE block
612  *
613  * RETURN:      Status
614  *
615  * DESCRIPTION: Install new GPE block with mutex support
616  *
617  ******************************************************************************/
618
619 static acpi_status
620 acpi_ev_install_gpe_block(struct acpi_gpe_block_info *gpe_block,
621                           u32 interrupt_number)
622 {
623         struct acpi_gpe_block_info *next_gpe_block;
624         struct acpi_gpe_xrupt_info *gpe_xrupt_block;
625         acpi_status status;
626         acpi_cpu_flags flags;
627
628         ACPI_FUNCTION_TRACE(ev_install_gpe_block);
629
630         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
631         if (ACPI_FAILURE(status)) {
632                 return_ACPI_STATUS(status);
633         }
634
635         gpe_xrupt_block = acpi_ev_get_gpe_xrupt_block(interrupt_number);
636         if (!gpe_xrupt_block) {
637                 status = AE_NO_MEMORY;
638                 goto unlock_and_exit;
639         }
640
641         /* Install the new block at the end of the list with lock */
642
643         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
644         if (gpe_xrupt_block->gpe_block_list_head) {
645                 next_gpe_block = gpe_xrupt_block->gpe_block_list_head;
646                 while (next_gpe_block->next) {
647                         next_gpe_block = next_gpe_block->next;
648                 }
649
650                 next_gpe_block->next = gpe_block;
651                 gpe_block->previous = next_gpe_block;
652         } else {
653                 gpe_xrupt_block->gpe_block_list_head = gpe_block;
654         }
655
656         gpe_block->xrupt_block = gpe_xrupt_block;
657         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
658
659       unlock_and_exit:
660         status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
661         return_ACPI_STATUS(status);
662 }
663
664 /*******************************************************************************
665  *
666  * FUNCTION:    acpi_ev_delete_gpe_block
667  *
668  * PARAMETERS:  gpe_block       - Existing GPE block
669  *
670  * RETURN:      Status
671  *
672  * DESCRIPTION: Remove a GPE block
673  *
674  ******************************************************************************/
675
676 acpi_status acpi_ev_delete_gpe_block(struct acpi_gpe_block_info *gpe_block)
677 {
678         acpi_status status;
679         acpi_cpu_flags flags;
680
681         ACPI_FUNCTION_TRACE(ev_install_gpe_block);
682
683         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
684         if (ACPI_FAILURE(status)) {
685                 return_ACPI_STATUS(status);
686         }
687
688         /* Disable all GPEs in this block */
689
690         status = acpi_hw_disable_gpe_block(gpe_block->xrupt_block, gpe_block);
691
692         if (!gpe_block->previous && !gpe_block->next) {
693
694                 /* This is the last gpe_block on this interrupt */
695
696                 status = acpi_ev_delete_gpe_xrupt(gpe_block->xrupt_block);
697                 if (ACPI_FAILURE(status)) {
698                         goto unlock_and_exit;
699                 }
700         } else {
701                 /* Remove the block on this interrupt with lock */
702
703                 flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
704                 if (gpe_block->previous) {
705                         gpe_block->previous->next = gpe_block->next;
706                 } else {
707                         gpe_block->xrupt_block->gpe_block_list_head =
708                             gpe_block->next;
709                 }
710
711                 if (gpe_block->next) {
712                         gpe_block->next->previous = gpe_block->previous;
713                 }
714                 acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
715         }
716
717         /* Free the gpe_block */
718
719         ACPI_FREE(gpe_block->register_info);
720         ACPI_FREE(gpe_block->event_info);
721         ACPI_FREE(gpe_block);
722
723       unlock_and_exit:
724         status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
725         return_ACPI_STATUS(status);
726 }
727
728 /*******************************************************************************
729  *
730  * FUNCTION:    acpi_ev_create_gpe_info_blocks
731  *
732  * PARAMETERS:  gpe_block   - New GPE block
733  *
734  * RETURN:      Status
735  *
736  * DESCRIPTION: Create the register_info and event_info blocks for this GPE block
737  *
738  ******************************************************************************/
739
740 static acpi_status
741 acpi_ev_create_gpe_info_blocks(struct acpi_gpe_block_info *gpe_block)
742 {
743         struct acpi_gpe_register_info *gpe_register_info = NULL;
744         struct acpi_gpe_event_info *gpe_event_info = NULL;
745         struct acpi_gpe_event_info *this_event;
746         struct acpi_gpe_register_info *this_register;
747         acpi_native_uint i;
748         acpi_native_uint j;
749         acpi_status status;
750
751         ACPI_FUNCTION_TRACE(ev_create_gpe_info_blocks);
752
753         /* Allocate the GPE register information block */
754
755         gpe_register_info = ACPI_ALLOCATE_ZEROED((acpi_size) gpe_block->
756                                                  register_count *
757                                                  sizeof(struct
758                                                         acpi_gpe_register_info));
759         if (!gpe_register_info) {
760                 ACPI_ERROR((AE_INFO,
761                             "Could not allocate the GpeRegisterInfo table"));
762                 return_ACPI_STATUS(AE_NO_MEMORY);
763         }
764
765         /*
766          * Allocate the GPE event_info block. There are eight distinct GPEs
767          * per register. Initialization to zeros is sufficient.
768          */
769         gpe_event_info = ACPI_ALLOCATE_ZEROED(((acpi_size) gpe_block->
770                                                register_count *
771                                                ACPI_GPE_REGISTER_WIDTH) *
772                                               sizeof(struct
773                                                      acpi_gpe_event_info));
774         if (!gpe_event_info) {
775                 ACPI_ERROR((AE_INFO,
776                             "Could not allocate the GpeEventInfo table"));
777                 status = AE_NO_MEMORY;
778                 goto error_exit;
779         }
780
781         /* Save the new Info arrays in the GPE block */
782
783         gpe_block->register_info = gpe_register_info;
784         gpe_block->event_info = gpe_event_info;
785
786         /*
787          * Initialize the GPE Register and Event structures. A goal of these
788          * tables is to hide the fact that there are two separate GPE register sets
789          * in a given GPE hardware block, the status registers occupy the first half,
790          * and the enable registers occupy the second half.
791          */
792         this_register = gpe_register_info;
793         this_event = gpe_event_info;
794
795         for (i = 0; i < gpe_block->register_count; i++) {
796
797                 /* Init the register_info for this GPE register (8 GPEs) */
798
799                 this_register->base_gpe_number =
800                     (u8) (gpe_block->block_base_number +
801                           (i * ACPI_GPE_REGISTER_WIDTH));
802
803                 this_register->status_address.address =
804                     gpe_block->block_address.address + i;
805
806                 this_register->enable_address.address =
807                     gpe_block->block_address.address + i +
808                     gpe_block->register_count;
809
810                 this_register->status_address.space_id =
811                     gpe_block->block_address.space_id;
812                 this_register->enable_address.space_id =
813                     gpe_block->block_address.space_id;
814                 this_register->status_address.bit_width =
815                     ACPI_GPE_REGISTER_WIDTH;
816                 this_register->enable_address.bit_width =
817                     ACPI_GPE_REGISTER_WIDTH;
818                 this_register->status_address.bit_offset =
819                     ACPI_GPE_REGISTER_WIDTH;
820                 this_register->enable_address.bit_offset =
821                     ACPI_GPE_REGISTER_WIDTH;
822
823                 /* Init the event_info for each GPE within this register */
824
825                 for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
826                         this_event->gpe_number =
827                             (u8) (this_register->base_gpe_number + j);
828                         this_event->register_info = this_register;
829                         this_event++;
830                 }
831
832                 /* Disable all GPEs within this register */
833
834                 status = acpi_hw_low_level_write(ACPI_GPE_REGISTER_WIDTH, 0x00,
835                                                  &this_register->
836                                                  enable_address);
837                 if (ACPI_FAILURE(status)) {
838                         goto error_exit;
839                 }
840
841                 /* Clear any pending GPE events within this register */
842
843                 status = acpi_hw_low_level_write(ACPI_GPE_REGISTER_WIDTH, 0xFF,
844                                                  &this_register->
845                                                  status_address);
846                 if (ACPI_FAILURE(status)) {
847                         goto error_exit;
848                 }
849
850                 this_register++;
851         }
852
853         return_ACPI_STATUS(AE_OK);
854
855       error_exit:
856         if (gpe_register_info) {
857                 ACPI_FREE(gpe_register_info);
858         }
859         if (gpe_event_info) {
860                 ACPI_FREE(gpe_event_info);
861         }
862
863         return_ACPI_STATUS(status);
864 }
865
866 /*******************************************************************************
867  *
868  * FUNCTION:    acpi_ev_create_gpe_block
869  *
870  * PARAMETERS:  gpe_device          - Handle to the parent GPE block
871  *              gpe_block_address   - Address and space_iD
872  *              register_count      - Number of GPE register pairs in the block
873  *              gpe_block_base_number - Starting GPE number for the block
874  *              interrupt_number    - H/W interrupt for the block
875  *              return_gpe_block    - Where the new block descriptor is returned
876  *
877  * RETURN:      Status
878  *
879  * DESCRIPTION: Create and Install a block of GPE registers. All GPEs within
880  *              the block are disabled at exit.
881  *              Note: Assumes namespace is locked.
882  *
883  ******************************************************************************/
884
885 acpi_status
886 acpi_ev_create_gpe_block(struct acpi_namespace_node *gpe_device,
887                          struct acpi_generic_address *gpe_block_address,
888                          u32 register_count,
889                          u8 gpe_block_base_number,
890                          u32 interrupt_number,
891                          struct acpi_gpe_block_info **return_gpe_block)
892 {
893         acpi_status status;
894         struct acpi_gpe_block_info *gpe_block;
895
896         ACPI_FUNCTION_TRACE(ev_create_gpe_block);
897
898         if (!register_count) {
899                 return_ACPI_STATUS(AE_OK);
900         }
901
902         /* Allocate a new GPE block */
903
904         gpe_block = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_block_info));
905         if (!gpe_block) {
906                 return_ACPI_STATUS(AE_NO_MEMORY);
907         }
908
909         /* Initialize the new GPE block */
910
911         gpe_block->node = gpe_device;
912         gpe_block->register_count = register_count;
913         gpe_block->block_base_number = gpe_block_base_number;
914
915         ACPI_MEMCPY(&gpe_block->block_address, gpe_block_address,
916                     sizeof(struct acpi_generic_address));
917
918         /*
919          * Create the register_info and event_info sub-structures
920          * Note: disables and clears all GPEs in the block
921          */
922         status = acpi_ev_create_gpe_info_blocks(gpe_block);
923         if (ACPI_FAILURE(status)) {
924                 ACPI_FREE(gpe_block);
925                 return_ACPI_STATUS(status);
926         }
927
928         /* Install the new block in the global lists */
929
930         status = acpi_ev_install_gpe_block(gpe_block, interrupt_number);
931         if (ACPI_FAILURE(status)) {
932                 ACPI_FREE(gpe_block);
933                 return_ACPI_STATUS(status);
934         }
935
936         /* Find all GPE methods (_Lxx, _Exx) for this block */
937
938         status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD, gpe_device,
939                                         ACPI_UINT32_MAX, ACPI_NS_WALK_NO_UNLOCK,
940                                         acpi_ev_save_method_info, gpe_block,
941                                         NULL);
942
943         /* Return the new block */
944
945         if (return_gpe_block) {
946                 (*return_gpe_block) = gpe_block;
947         }
948
949         ACPI_DEBUG_PRINT((ACPI_DB_INIT,
950                           "GPE %02X to %02X [%4.4s] %u regs on int 0x%X\n",
951                           (u32) gpe_block->block_base_number,
952                           (u32) (gpe_block->block_base_number +
953                                  ((gpe_block->register_count *
954                                    ACPI_GPE_REGISTER_WIDTH) - 1)),
955                           gpe_device->name.ascii, gpe_block->register_count,
956                           interrupt_number));
957
958         return_ACPI_STATUS(AE_OK);
959 }
960
961 /*******************************************************************************
962  *
963  * FUNCTION:    acpi_ev_initialize_gpe_block
964  *
965  * PARAMETERS:  gpe_device          - Handle to the parent GPE block
966  *              gpe_block           - Gpe Block info
967  *
968  * RETURN:      Status
969  *
970  * DESCRIPTION: Initialize and enable a GPE block. First find and run any
971  *              _PRT methods associated with the block, then enable the
972  *              appropriate GPEs.
973  *              Note: Assumes namespace is locked.
974  *
975  ******************************************************************************/
976
977 acpi_status
978 acpi_ev_initialize_gpe_block(struct acpi_namespace_node *gpe_device,
979                              struct acpi_gpe_block_info *gpe_block)
980 {
981         acpi_status status;
982         struct acpi_gpe_event_info *gpe_event_info;
983         struct acpi_gpe_walk_info gpe_info;
984         u32 wake_gpe_count;
985         u32 gpe_enabled_count;
986         acpi_native_uint i;
987         acpi_native_uint j;
988
989         ACPI_FUNCTION_TRACE(ev_initialize_gpe_block);
990
991         /* Ignore a null GPE block (e.g., if no GPE block 1 exists) */
992
993         if (!gpe_block) {
994                 return_ACPI_STATUS(AE_OK);
995         }
996
997         /*
998          * Runtime option: Should wake GPEs be enabled at runtime?  The default
999          * is no, they should only be enabled just as the machine goes to sleep.
1000          */
1001         if (acpi_gbl_leave_wake_gpes_disabled) {
1002                 /*
1003                  * Differentiate runtime vs wake GPEs, via the _PRW control methods.
1004                  * Each GPE that has one or more _PRWs that reference it is by
1005                  * definition a wake GPE and will not be enabled while the machine
1006                  * is running.
1007                  */
1008                 gpe_info.gpe_block = gpe_block;
1009                 gpe_info.gpe_device = gpe_device;
1010
1011                 status =
1012                     acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
1013                                            ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
1014                                            acpi_ev_match_prw_and_gpe, &gpe_info,
1015                                            NULL);
1016         }
1017
1018         /*
1019          * Enable all GPEs in this block that have these attributes:
1020          * 1) are "runtime" or "run/wake" GPEs, and
1021          * 2) have a corresponding _Lxx or _Exx method
1022          *
1023          * Any other GPEs within this block must be enabled via the acpi_enable_gpe()
1024          * external interface.
1025          */
1026         wake_gpe_count = 0;
1027         gpe_enabled_count = 0;
1028
1029         for (i = 0; i < gpe_block->register_count; i++) {
1030                 for (j = 0; j < 8; j++) {
1031
1032                         /* Get the info block for this particular GPE */
1033
1034                         gpe_event_info =
1035                             &gpe_block->
1036                             event_info[(i * ACPI_GPE_REGISTER_WIDTH) + j];
1037
1038                         if (((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
1039                              ACPI_GPE_DISPATCH_METHOD)
1040                             && (gpe_event_info->flags & ACPI_GPE_TYPE_RUNTIME)) {
1041                                 gpe_enabled_count++;
1042                         }
1043
1044                         if (gpe_event_info->flags & ACPI_GPE_TYPE_WAKE) {
1045                                 wake_gpe_count++;
1046                         }
1047                 }
1048         }
1049
1050         ACPI_DEBUG_PRINT((ACPI_DB_INIT,
1051                           "Found %u Wake, Enabled %u Runtime GPEs in this block\n",
1052                           wake_gpe_count, gpe_enabled_count));
1053
1054         /* Enable all valid runtime GPEs found above */
1055
1056         status = acpi_hw_enable_runtime_gpe_block(NULL, gpe_block);
1057         if (ACPI_FAILURE(status)) {
1058                 ACPI_ERROR((AE_INFO, "Could not enable GPEs in GpeBlock %p",
1059                             gpe_block));
1060         }
1061
1062         return_ACPI_STATUS(status);
1063 }
1064
1065 /*******************************************************************************
1066  *
1067  * FUNCTION:    acpi_ev_gpe_initialize
1068  *
1069  * PARAMETERS:  None
1070  *
1071  * RETURN:      Status
1072  *
1073  * DESCRIPTION: Initialize the GPE data structures
1074  *
1075  ******************************************************************************/
1076
1077 acpi_status acpi_ev_gpe_initialize(void)
1078 {
1079         u32 register_count0 = 0;
1080         u32 register_count1 = 0;
1081         u32 gpe_number_max = 0;
1082         acpi_status status;
1083
1084         ACPI_FUNCTION_TRACE(ev_gpe_initialize);
1085
1086         status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
1087         if (ACPI_FAILURE(status)) {
1088                 return_ACPI_STATUS(status);
1089         }
1090
1091         /*
1092          * Initialize the GPE Block(s) defined in the FADT
1093          *
1094          * Why the GPE register block lengths are divided by 2:  From the ACPI Spec,
1095          * section "General-Purpose Event Registers", we have:
1096          *
1097          * "Each register block contains two registers of equal length
1098          *  GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
1099          *  GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
1100          *  The length of the GPE1_STS and GPE1_EN registers is equal to
1101          *  half the GPE1_LEN. If a generic register block is not supported
1102          *  then its respective block pointer and block length values in the
1103          *  FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
1104          *  to be the same size."
1105          */
1106
1107         /*
1108          * Determine the maximum GPE number for this machine.
1109          *
1110          * Note: both GPE0 and GPE1 are optional, and either can exist without
1111          * the other.
1112          *
1113          * If EITHER the register length OR the block address are zero, then that
1114          * particular block is not supported.
1115          */
1116         if (acpi_gbl_FADT.gpe0_block_length &&
1117             acpi_gbl_FADT.xgpe0_block.address) {
1118
1119                 /* GPE block 0 exists (has both length and address > 0) */
1120
1121                 register_count0 = (u16) (acpi_gbl_FADT.gpe0_block_length / 2);
1122
1123                 gpe_number_max =
1124                     (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;
1125
1126                 /* Install GPE Block 0 */
1127
1128                 status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
1129                                                   &acpi_gbl_FADT.xgpe0_block,
1130                                                   register_count0, 0,
1131                                                   acpi_gbl_FADT.sci_interrupt,
1132                                                   &acpi_gbl_gpe_fadt_blocks[0]);
1133
1134                 if (ACPI_FAILURE(status)) {
1135                         ACPI_EXCEPTION((AE_INFO, status,
1136                                         "Could not create GPE Block 0"));
1137                 }
1138         }
1139
1140         if (acpi_gbl_FADT.gpe1_block_length &&
1141             acpi_gbl_FADT.xgpe1_block.address) {
1142
1143                 /* GPE block 1 exists (has both length and address > 0) */
1144
1145                 register_count1 = (u16) (acpi_gbl_FADT.gpe1_block_length / 2);
1146
1147                 /* Check for GPE0/GPE1 overlap (if both banks exist) */
1148
1149                 if ((register_count0) &&
1150                     (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
1151                         ACPI_ERROR((AE_INFO,
1152                                     "GPE0 block (GPE 0 to %d) overlaps the GPE1 block (GPE %d to %d) - Ignoring GPE1",
1153                                     gpe_number_max, acpi_gbl_FADT.gpe1_base,
1154                                     acpi_gbl_FADT.gpe1_base +
1155                                     ((register_count1 *
1156                                       ACPI_GPE_REGISTER_WIDTH) - 1)));
1157
1158                         /* Ignore GPE1 block by setting the register count to zero */
1159
1160                         register_count1 = 0;
1161                 } else {
1162                         /* Install GPE Block 1 */
1163
1164                         status =
1165                             acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
1166                                                      &acpi_gbl_FADT.xgpe1_block,
1167                                                      register_count1,
1168                                                      acpi_gbl_FADT.gpe1_base,
1169                                                      acpi_gbl_FADT.
1170                                                      sci_interrupt,
1171                                                      &acpi_gbl_gpe_fadt_blocks
1172                                                      [1]);
1173
1174                         if (ACPI_FAILURE(status)) {
1175                                 ACPI_EXCEPTION((AE_INFO, status,
1176                                                 "Could not create GPE Block 1"));
1177                         }
1178
1179                         /*
1180                          * GPE0 and GPE1 do not have to be contiguous in the GPE number
1181                          * space. However, GPE0 always starts at GPE number zero.
1182                          */
1183                         gpe_number_max = acpi_gbl_FADT.gpe1_base +
1184                             ((register_count1 * ACPI_GPE_REGISTER_WIDTH) - 1);
1185                 }
1186         }
1187
1188         /* Exit if there are no GPE registers */
1189
1190         if ((register_count0 + register_count1) == 0) {
1191
1192                 /* GPEs are not required by ACPI, this is OK */
1193
1194                 ACPI_DEBUG_PRINT((ACPI_DB_INIT,
1195                                   "There are no GPE blocks defined in the FADT\n"));
1196                 status = AE_OK;
1197                 goto cleanup;
1198         }
1199
1200         /* Check for Max GPE number out-of-range */
1201
1202         if (gpe_number_max > ACPI_GPE_MAX) {
1203                 ACPI_ERROR((AE_INFO,
1204                             "Maximum GPE number from FADT is too large: 0x%X",
1205                             gpe_number_max));
1206                 status = AE_BAD_VALUE;
1207                 goto cleanup;
1208         }
1209
1210       cleanup:
1211         (void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
1212         return_ACPI_STATUS(AE_OK);
1213 }