Merge branch 'acpica' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux...
[sfrench/cifs-2.6.git] / drivers / acpi / acpica / evgpe.c
1 /******************************************************************************
2  *
3  * Module Name: evgpe - General Purpose Event handling and dispatch
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2010, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "acevents.h"
47 #include "acnamesp.h"
48
49 #define _COMPONENT          ACPI_EVENTS
50 ACPI_MODULE_NAME("evgpe")
51
52 /* Local prototypes */
53 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);
54
55 /*******************************************************************************
56  *
57  * FUNCTION:    acpi_ev_update_gpe_enable_masks
58  *
59  * PARAMETERS:  gpe_event_info          - GPE to update
60  *
61  * RETURN:      Status
62  *
63  * DESCRIPTION: Updates GPE register enable masks based upon whether there are
64  *              references (either wake or run) to this GPE
65  *
66  ******************************************************************************/
67
68 acpi_status
69 acpi_ev_update_gpe_enable_masks(struct acpi_gpe_event_info *gpe_event_info)
70 {
71         struct acpi_gpe_register_info *gpe_register_info;
72         u8 register_bit;
73
74         ACPI_FUNCTION_TRACE(ev_update_gpe_enable_masks);
75
76         gpe_register_info = gpe_event_info->register_info;
77         if (!gpe_register_info) {
78                 return_ACPI_STATUS(AE_NOT_EXIST);
79         }
80
81         register_bit = (u8)
82             (1 <<
83              (gpe_event_info->gpe_number - gpe_register_info->base_gpe_number));
84
85         /* Clear the wake/run bits up front */
86
87         ACPI_CLEAR_BIT(gpe_register_info->enable_for_wake, register_bit);
88         ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
89
90         /* Set the mask bits only if there are references to this GPE */
91
92         if (gpe_event_info->runtime_count) {
93                 ACPI_SET_BIT(gpe_register_info->enable_for_run, register_bit);
94         }
95
96         if (gpe_event_info->wakeup_count) {
97                 ACPI_SET_BIT(gpe_register_info->enable_for_wake, register_bit);
98         }
99
100         return_ACPI_STATUS(AE_OK);
101 }
102
103 /*******************************************************************************
104  *
105  * FUNCTION:    acpi_ev_enable_gpe
106  *
107  * PARAMETERS:  gpe_event_info          - GPE to enable
108  *
109  * RETURN:      Status
110  *
111  * DESCRIPTION: Hardware-enable a GPE. Always enables the GPE, regardless
112  *              of type or number of references.
113  *
114  * Note: The GPE lock should be already acquired when this function is called.
115  *
116  ******************************************************************************/
117
118 acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
119 {
120         acpi_status status;
121
122
123         ACPI_FUNCTION_TRACE(ev_enable_gpe);
124
125
126         /*
127          * We will only allow a GPE to be enabled if it has either an
128          * associated method (_Lxx/_Exx) or a handler. Otherwise, the
129          * GPE will be immediately disabled by acpi_ev_gpe_dispatch the
130          * first time it fires.
131          */
132         if (!(gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK)) {
133                 return_ACPI_STATUS(AE_NO_HANDLER);
134         }
135
136         /* Ensure the HW enable masks are current */
137
138         status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
139         if (ACPI_FAILURE(status)) {
140                 return_ACPI_STATUS(status);
141         }
142
143         /* Clear the GPE (of stale events) */
144
145         status = acpi_hw_clear_gpe(gpe_event_info);
146         if (ACPI_FAILURE(status)) {
147                 return_ACPI_STATUS(status);
148         }
149
150         /* Enable the requested GPE */
151
152         status = acpi_hw_write_gpe_enable_reg(gpe_event_info);
153         return_ACPI_STATUS(status);
154 }
155
156 /*******************************************************************************
157  *
158  * FUNCTION:    acpi_ev_disable_gpe
159  *
160  * PARAMETERS:  gpe_event_info          - GPE to disable
161  *
162  * RETURN:      Status
163  *
164  * DESCRIPTION: Hardware-disable a GPE. Always disables the requested GPE,
165  *              regardless of the type or number of references.
166  *
167  * Note: The GPE lock should be already acquired when this function is called.
168  *
169  ******************************************************************************/
170
171 acpi_status acpi_ev_disable_gpe(struct acpi_gpe_event_info *gpe_event_info)
172 {
173         acpi_status status;
174
175         ACPI_FUNCTION_TRACE(ev_disable_gpe);
176
177
178         /*
179          * Note: Always disable the GPE, even if we think that that it is already
180          * disabled. It is possible that the AML or some other code has enabled
181          * the GPE behind our back.
182          */
183
184         /* Ensure the HW enable masks are current */
185
186         status = acpi_ev_update_gpe_enable_masks(gpe_event_info);
187         if (ACPI_FAILURE(status)) {
188                 return_ACPI_STATUS(status);
189         }
190
191         /*
192          * Always H/W disable this GPE, even if we don't know the GPE type.
193          * Simply clear the enable bit for this particular GPE, but do not
194          * write out the current GPE enable mask since this may inadvertently
195          * enable GPEs too early. An example is a rogue GPE that has arrived
196          * during ACPICA initialization - possibly because AML or other code
197          * has enabled the GPE.
198          */
199         status = acpi_hw_low_disable_gpe(gpe_event_info);
200         return_ACPI_STATUS(status);
201 }
202
203
204 /*******************************************************************************
205  *
206  * FUNCTION:    acpi_ev_low_get_gpe_info
207  *
208  * PARAMETERS:  gpe_number          - Raw GPE number
209  *              gpe_block           - A GPE info block
210  *
211  * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
212  *              is not within the specified GPE block)
213  *
214  * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
215  *              the low-level implementation of ev_get_gpe_event_info.
216  *
217  ******************************************************************************/
218
219 struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
220                                                      struct acpi_gpe_block_info
221                                                      *gpe_block)
222 {
223         u32 gpe_index;
224
225         /*
226          * Validate that the gpe_number is within the specified gpe_block.
227          * (Two steps)
228          */
229         if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
230                 return (NULL);
231         }
232
233         gpe_index = gpe_number - gpe_block->block_base_number;
234         if (gpe_index >= gpe_block->gpe_count) {
235                 return (NULL);
236         }
237
238         return (&gpe_block->event_info[gpe_index]);
239 }
240
241
242 /*******************************************************************************
243  *
244  * FUNCTION:    acpi_ev_get_gpe_event_info
245  *
246  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
247  *              gpe_number          - Raw GPE number
248  *
249  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
250  *
251  * DESCRIPTION: Returns the event_info struct associated with this GPE.
252  *              Validates the gpe_block and the gpe_number
253  *
254  *              Should be called only when the GPE lists are semaphore locked
255  *              and not subject to change.
256  *
257  ******************************************************************************/
258
259 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
260                                                        u32 gpe_number)
261 {
262         union acpi_operand_object *obj_desc;
263         struct acpi_gpe_event_info *gpe_info;
264         u32 i;
265
266         ACPI_FUNCTION_ENTRY();
267
268         /* A NULL gpe_device means use the FADT-defined GPE block(s) */
269
270         if (!gpe_device) {
271
272                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
273
274                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
275                         gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
276                                                             acpi_gbl_gpe_fadt_blocks
277                                                             [i]);
278                         if (gpe_info) {
279                                 return (gpe_info);
280                         }
281                 }
282
283                 /* The gpe_number was not in the range of either FADT GPE block */
284
285                 return (NULL);
286         }
287
288         /* A Non-NULL gpe_device means this is a GPE Block Device */
289
290         obj_desc = acpi_ns_get_attached_object((struct acpi_namespace_node *)
291                                                gpe_device);
292         if (!obj_desc || !obj_desc->device.gpe_block) {
293                 return (NULL);
294         }
295
296         return (acpi_ev_low_get_gpe_info
297                 (gpe_number, obj_desc->device.gpe_block));
298 }
299
300 /*******************************************************************************
301  *
302  * FUNCTION:    acpi_ev_gpe_detect
303  *
304  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
305  *                                    Can have multiple GPE blocks attached.
306  *
307  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
308  *
309  * DESCRIPTION: Detect if any GP events have occurred. This function is
310  *              executed at interrupt level.
311  *
312  ******************************************************************************/
313
314 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
315 {
316         acpi_status status;
317         struct acpi_gpe_block_info *gpe_block;
318         struct acpi_gpe_register_info *gpe_register_info;
319         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
320         u8 enabled_status_byte;
321         u32 status_reg;
322         u32 enable_reg;
323         acpi_cpu_flags flags;
324         u32 i;
325         u32 j;
326
327         ACPI_FUNCTION_NAME(ev_gpe_detect);
328
329         /* Check for the case where there are no GPEs */
330
331         if (!gpe_xrupt_list) {
332                 return (int_status);
333         }
334
335         /*
336          * We need to obtain the GPE lock for both the data structs and registers
337          * Note: Not necessary to obtain the hardware lock, since the GPE
338          * registers are owned by the gpe_lock.
339          */
340         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
341
342         /* Examine all GPE blocks attached to this interrupt level */
343
344         gpe_block = gpe_xrupt_list->gpe_block_list_head;
345         while (gpe_block) {
346                 /*
347                  * Read all of the 8-bit GPE status and enable registers in this GPE
348                  * block, saving all of them. Find all currently active GP events.
349                  */
350                 for (i = 0; i < gpe_block->register_count; i++) {
351
352                         /* Get the next status/enable pair */
353
354                         gpe_register_info = &gpe_block->register_info[i];
355
356                         /* Read the Status Register */
357
358                         status =
359                             acpi_hw_read(&status_reg,
360                                          &gpe_register_info->status_address);
361                         if (ACPI_FAILURE(status)) {
362                                 goto unlock_and_exit;
363                         }
364
365                         /* Read the Enable Register */
366
367                         status =
368                             acpi_hw_read(&enable_reg,
369                                          &gpe_register_info->enable_address);
370                         if (ACPI_FAILURE(status)) {
371                                 goto unlock_and_exit;
372                         }
373
374                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
375                                           "Read GPE Register at GPE%X: Status=%02X, Enable=%02X\n",
376                                           gpe_register_info->base_gpe_number,
377                                           status_reg, enable_reg));
378
379                         /* Check if there is anything active at all in this register */
380
381                         enabled_status_byte = (u8) (status_reg & enable_reg);
382                         if (!enabled_status_byte) {
383
384                                 /* No active GPEs in this register, move on */
385
386                                 continue;
387                         }
388
389                         /* Now look at the individual GPEs in this byte register */
390
391                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
392
393                                 /* Examine one GPE bit */
394
395                                 if (enabled_status_byte & (1 << j)) {
396                                         /*
397                                          * Found an active GPE. Dispatch the event to a handler
398                                          * or method.
399                                          */
400                                         int_status |=
401                                             acpi_ev_gpe_dispatch(&gpe_block->
402                                                 event_info[((acpi_size) i * ACPI_GPE_REGISTER_WIDTH) + j], j + gpe_register_info->base_gpe_number);
403                                 }
404                         }
405                 }
406
407                 gpe_block = gpe_block->next;
408         }
409
410       unlock_and_exit:
411
412         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
413         return (int_status);
414 }
415
416 /*******************************************************************************
417  *
418  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
419  *
420  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
421  *
422  * RETURN:      None
423  *
424  * DESCRIPTION: Perform the actual execution of a GPE control method. This
425  *              function is called from an invocation of acpi_os_execute and
426  *              therefore does NOT execute at interrupt level - so that
427  *              the control method itself is not executed in the context of
428  *              an interrupt handler.
429  *
430  ******************************************************************************/
431 static void acpi_ev_asynch_enable_gpe(void *context);
432
433 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
434 {
435         struct acpi_gpe_event_info *gpe_event_info = (void *)context;
436         acpi_status status;
437         struct acpi_gpe_event_info local_gpe_event_info;
438         struct acpi_evaluate_info *info;
439
440         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
441
442         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
443         if (ACPI_FAILURE(status)) {
444                 return_VOID;
445         }
446
447         /* Must revalidate the gpe_number/gpe_block */
448
449         if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
450                 status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
451                 return_VOID;
452         }
453
454         /* Update the GPE register masks for return to enabled state */
455
456         (void)acpi_ev_update_gpe_enable_masks(gpe_event_info);
457
458         /*
459          * Take a snapshot of the GPE info for this level - we copy the info to
460          * prevent a race condition with remove_handler/remove_block.
461          */
462         ACPI_MEMCPY(&local_gpe_event_info, gpe_event_info,
463                     sizeof(struct acpi_gpe_event_info));
464
465         status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
466         if (ACPI_FAILURE(status)) {
467                 return_VOID;
468         }
469
470         /*
471          * Must check for control method type dispatch one more time to avoid a
472          * race with ev_gpe_install_handler
473          */
474         if ((local_gpe_event_info.flags & ACPI_GPE_DISPATCH_MASK) ==
475             ACPI_GPE_DISPATCH_METHOD) {
476
477                 /* Allocate the evaluation information block */
478
479                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
480                 if (!info) {
481                         status = AE_NO_MEMORY;
482                 } else {
483                         /*
484                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the _Lxx/_Exx
485                          * control method that corresponds to this GPE
486                          */
487                         info->prefix_node =
488                             local_gpe_event_info.dispatch.method_node;
489                         info->flags = ACPI_IGNORE_RETURN_VALUE;
490
491                         status = acpi_ns_evaluate(info);
492                         ACPI_FREE(info);
493                 }
494
495                 if (ACPI_FAILURE(status)) {
496                         ACPI_EXCEPTION((AE_INFO, status,
497                                         "while evaluating GPE method [%4.4s]",
498                                         acpi_ut_get_node_name
499                                         (local_gpe_event_info.dispatch.
500                                          method_node)));
501                 }
502         }
503         /* Defer enabling of GPE until all notify handlers are done */
504         acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_asynch_enable_gpe,
505                                 gpe_event_info);
506         return_VOID;
507 }
508
509 static void acpi_ev_asynch_enable_gpe(void *context)
510 {
511         struct acpi_gpe_event_info *gpe_event_info = context;
512         acpi_status status;
513         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
514             ACPI_GPE_LEVEL_TRIGGERED) {
515                 /*
516                  * GPE is level-triggered, we clear the GPE status bit after handling
517                  * the event.
518                  */
519                 status = acpi_hw_clear_gpe(gpe_event_info);
520                 if (ACPI_FAILURE(status)) {
521                         return_VOID;
522                 }
523         }
524
525         /* Enable this GPE */
526         (void)acpi_hw_write_gpe_enable_reg(gpe_event_info);
527         return_VOID;
528 }
529
530 /*******************************************************************************
531  *
532  * FUNCTION:    acpi_ev_gpe_dispatch
533  *
534  * PARAMETERS:  gpe_event_info  - Info for this GPE
535  *              gpe_number      - Number relative to the parent GPE block
536  *
537  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
538  *
539  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
540  *              or method (e.g. _Lxx/_Exx) handler.
541  *
542  *              This function executes at interrupt level.
543  *
544  ******************************************************************************/
545
546 u32
547 acpi_ev_gpe_dispatch(struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
548 {
549         acpi_status status;
550
551         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
552
553         acpi_os_gpe_count(gpe_number);
554
555         /*
556          * If edge-triggered, clear the GPE status bit now. Note that
557          * level-triggered events are cleared after the GPE is serviced.
558          */
559         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
560             ACPI_GPE_EDGE_TRIGGERED) {
561                 status = acpi_hw_clear_gpe(gpe_event_info);
562                 if (ACPI_FAILURE(status)) {
563                         ACPI_EXCEPTION((AE_INFO, status,
564                                         "Unable to clear GPE[0x%2X]",
565                                         gpe_number));
566                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
567                 }
568         }
569
570         /*
571          * Dispatch the GPE to either an installed handler, or the control method
572          * associated with this GPE (_Lxx or _Exx). If a handler exists, we invoke
573          * it and do not attempt to run the method. If there is neither a handler
574          * nor a method, we disable this GPE to prevent further such pointless
575          * events from firing.
576          */
577         switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
578         case ACPI_GPE_DISPATCH_HANDLER:
579
580                 /*
581                  * Invoke the installed handler (at interrupt level)
582                  * Ignore return status for now.
583                  * TBD: leave GPE disabled on error?
584                  */
585                 (void)gpe_event_info->dispatch.handler->address(gpe_event_info->
586                                                                 dispatch.
587                                                                 handler->
588                                                                 context);
589
590                 /* It is now safe to clear level-triggered events. */
591
592                 if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
593                     ACPI_GPE_LEVEL_TRIGGERED) {
594                         status = acpi_hw_clear_gpe(gpe_event_info);
595                         if (ACPI_FAILURE(status)) {
596                                 ACPI_EXCEPTION((AE_INFO, status,
597                                         "Unable to clear GPE[0x%2X]",
598                                                 gpe_number));
599                                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
600                         }
601                 }
602                 break;
603
604         case ACPI_GPE_DISPATCH_METHOD:
605
606                 /*
607                  * Disable the GPE, so it doesn't keep firing before the method has a
608                  * chance to run (it runs asynchronously with interrupts enabled).
609                  */
610                 status = acpi_ev_disable_gpe(gpe_event_info);
611                 if (ACPI_FAILURE(status)) {
612                         ACPI_EXCEPTION((AE_INFO, status,
613                                         "Unable to disable GPE[0x%2X]",
614                                         gpe_number));
615                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
616                 }
617
618                 /*
619                  * Execute the method associated with the GPE
620                  * NOTE: Level-triggered GPEs are cleared after the method completes.
621                  */
622                 status = acpi_os_execute(OSL_GPE_HANDLER,
623                                          acpi_ev_asynch_execute_gpe_method,
624                                          gpe_event_info);
625                 if (ACPI_FAILURE(status)) {
626                         ACPI_EXCEPTION((AE_INFO, status,
627                                         "Unable to queue handler for GPE[0x%2X] - event disabled",
628                                         gpe_number));
629                 }
630                 break;
631
632         default:
633
634                 /*
635                  * No handler or method to run!
636                  * 03/2010: This case should no longer be possible. We will not allow
637                  * a GPE to be enabled if it has no handler or method.
638                  */
639                 ACPI_ERROR((AE_INFO,
640                             "No handler or method for GPE[0x%2X], disabling event",
641                             gpe_number));
642
643                 /*
644                  * Disable the GPE. The GPE will remain disabled a handler
645                  * is installed or ACPICA is restarted.
646                  */
647                 status = acpi_ev_disable_gpe(gpe_event_info);
648                 if (ACPI_FAILURE(status)) {
649                         ACPI_EXCEPTION((AE_INFO, status,
650                                         "Unable to disable GPE[0x%2X]",
651                                         gpe_number));
652                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
653                 }
654                 break;
655         }
656
657         return_UINT32(ACPI_INTERRUPT_HANDLED);
658 }