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 - 2016, 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 #if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
  52 /* Local prototypes */
  53 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);
  54
  55 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context);
  56
  57 /*******************************************************************************
  58  *
  59  * FUNCTION:    acpi_ev_update_gpe_enable_mask
  60  *
  61  * PARAMETERS:  gpe_event_info          - GPE to update
  62  *
  63  * RETURN:      Status
  64  *
  65  * DESCRIPTION: Updates GPE register enable mask based upon whether there are
  66  *              runtime references to this GPE
  67  *
  68  ******************************************************************************/
  69
  70 acpi_status
  71 acpi_ev_update_gpe_enable_mask(struct acpi_gpe_event_info *gpe_event_info)
  72 {
  73         struct acpi_gpe_register_info *gpe_register_info;
  74         u32 register_bit;
  75
  76         ACPI_FUNCTION_TRACE(ev_update_gpe_enable_mask);
  77
  78         gpe_register_info = gpe_event_info->register_info;
  79         if (!gpe_register_info) {
  80                 return_ACPI_STATUS(AE_NOT_EXIST);
  81         }
  82
  83         register_bit = acpi_hw_get_gpe_register_bit(gpe_event_info);
  84
  85         /* Clear the run bit up front */
  86
  87         ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);
  88
  89         /* Set the mask bit only if there are references to this GPE */
  90
  91         if (gpe_event_info->runtime_count) {
  92                 ACPI_SET_BIT(gpe_register_info->enable_for_run,
  93                              (u8)register_bit);
  94         }
  95
  96         gpe_register_info->enable_mask = gpe_register_info->enable_for_run;
  97         return_ACPI_STATUS(AE_OK);
  98 }
  99
 100 /*******************************************************************************
 101  *
 102  * FUNCTION:    acpi_ev_enable_gpe
 103  *
 104  * PARAMETERS:  gpe_event_info          - GPE to enable
 105  *
 106  * RETURN:      Status
 107  *
 108  * DESCRIPTION: Clear a GPE of stale events and enable it.
 109  *
 110  ******************************************************************************/
 111
 112 acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 113 {
 114         acpi_status status;
 115
 116         ACPI_FUNCTION_TRACE(ev_enable_gpe);
 117
 118         /* Clear the GPE (of stale events) */
 119
 120         status = acpi_hw_clear_gpe(gpe_event_info);
 121         if (ACPI_FAILURE(status)) {
 122                 return_ACPI_STATUS(status);
 123         }
 124
 125         /* Enable the requested GPE */
 126
 127         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE);
 128         return_ACPI_STATUS(status);
 129 }
 130
 131 /*******************************************************************************
 132  *
 133  * FUNCTION:    acpi_ev_mask_gpe
 134  *
 135  * PARAMETERS:  gpe_event_info          - GPE to be blocked/unblocked
 136  *              is_masked               - Whether the GPE is masked or not
 137  *
 138  * RETURN:      Status
 139  *
 140  * DESCRIPTION: Unconditionally mask/unmask a GPE during runtime.
 141  *
 142  ******************************************************************************/
 143
 144 acpi_status
 145 acpi_ev_mask_gpe(struct acpi_gpe_event_info *gpe_event_info, u8 is_masked)
 146 {
 147         struct acpi_gpe_register_info *gpe_register_info;
 148         u32 register_bit;
 149
 150         ACPI_FUNCTION_TRACE(ev_mask_gpe);
 151
 152         gpe_register_info = gpe_event_info->register_info;
 153         if (!gpe_register_info) {
 154                 return_ACPI_STATUS(AE_NOT_EXIST);
 155         }
 156
 157         register_bit = acpi_hw_get_gpe_register_bit(gpe_event_info);
 158
 159         /* Perform the action */
 160
 161         if (is_masked) {
 162                 if (register_bit & gpe_register_info->mask_for_run) {
 163                         return_ACPI_STATUS(AE_BAD_PARAMETER);
 164                 }
 165
 166                 (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 167                 ACPI_SET_BIT(gpe_register_info->mask_for_run, (u8)register_bit);
 168         } else {
 169                 if (!(register_bit & gpe_register_info->mask_for_run)) {
 170                         return_ACPI_STATUS(AE_BAD_PARAMETER);
 171                 }
 172
 173                 ACPI_CLEAR_BIT(gpe_register_info->mask_for_run,
 174                                (u8)register_bit);
 175                 if (gpe_event_info->runtime_count
 176                     && !gpe_event_info->disable_for_dispatch) {
 177                         (void)acpi_hw_low_set_gpe(gpe_event_info,
 178                                                   ACPI_GPE_ENABLE);
 179                 }
 180         }
 181
 182         return_ACPI_STATUS(AE_OK);
 183 }
 184
 185 /*******************************************************************************
 186  *
 187  * FUNCTION:    acpi_ev_add_gpe_reference
 188  *
 189  * PARAMETERS:  gpe_event_info          - Add a reference to this GPE
 190  *
 191  * RETURN:      Status
 192  *
 193  * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
 194  *              hardware-enabled.
 195  *
 196  ******************************************************************************/
 197
 198 acpi_status
 199 acpi_ev_add_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 200 {
 201         acpi_status status = AE_OK;
 202
 203         ACPI_FUNCTION_TRACE(ev_add_gpe_reference);
 204
 205         if (gpe_event_info->runtime_count == ACPI_UINT8_MAX) {
 206                 return_ACPI_STATUS(AE_LIMIT);
 207         }
 208
 209         gpe_event_info->runtime_count++;
 210         if (gpe_event_info->runtime_count == 1) {
 211
 212                 /* Enable on first reference */
 213
 214                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 215                 if (ACPI_SUCCESS(status)) {
 216                         status = acpi_ev_enable_gpe(gpe_event_info);
 217                 }
 218
 219                 if (ACPI_FAILURE(status)) {
 220                         gpe_event_info->runtime_count--;
 221                 }
 222         }
 223
 224         return_ACPI_STATUS(status);
 225 }
 226
 227 /*******************************************************************************
 228  *
 229  * FUNCTION:    acpi_ev_remove_gpe_reference
 230  *
 231  * PARAMETERS:  gpe_event_info          - Remove a reference to this GPE
 232  *
 233  * RETURN:      Status
 234  *
 235  * DESCRIPTION: Remove a reference to a GPE. When the last reference is
 236  *              removed, the GPE is hardware-disabled.
 237  *
 238  ******************************************************************************/
 239
 240 acpi_status
 241 acpi_ev_remove_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 242 {
 243         acpi_status status = AE_OK;
 244
 245         ACPI_FUNCTION_TRACE(ev_remove_gpe_reference);
 246
 247         if (!gpe_event_info->runtime_count) {
 248                 return_ACPI_STATUS(AE_LIMIT);
 249         }
 250
 251         gpe_event_info->runtime_count--;
 252         if (!gpe_event_info->runtime_count) {
 253
 254                 /* Disable on last reference */
 255
 256                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 257                 if (ACPI_SUCCESS(status)) {
 258                         status =
 259                             acpi_hw_low_set_gpe(gpe_event_info,
 260                                                 ACPI_GPE_DISABLE);
 261                 }
 262
 263                 if (ACPI_FAILURE(status)) {
 264                         gpe_event_info->runtime_count++;
 265                 }
 266         }
 267
 268         return_ACPI_STATUS(status);
 269 }
 270
 271 /*******************************************************************************
 272  *
 273  * FUNCTION:    acpi_ev_low_get_gpe_info
 274  *
 275  * PARAMETERS:  gpe_number          - Raw GPE number
 276  *              gpe_block           - A GPE info block
 277  *
 278  * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
 279  *              is not within the specified GPE block)
 280  *
 281  * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
 282  *              the low-level implementation of ev_get_gpe_event_info.
 283  *
 284  ******************************************************************************/
 285
 286 struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
 287                                                      struct acpi_gpe_block_info
 288                                                      *gpe_block)
 289 {
 290         u32 gpe_index;
 291
 292         /*
 293          * Validate that the gpe_number is within the specified gpe_block.
 294          * (Two steps)
 295          */
 296         if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
 297                 return (NULL);
 298         }
 299
 300         gpe_index = gpe_number - gpe_block->block_base_number;
 301         if (gpe_index >= gpe_block->gpe_count) {
 302                 return (NULL);
 303         }
 304
 305         return (&gpe_block->event_info[gpe_index]);
 306 }
 307
 308
 309 /*******************************************************************************
 310  *
 311  * FUNCTION:    acpi_ev_get_gpe_event_info
 312  *
 313  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 314  *              gpe_number          - Raw GPE number
 315  *
 316  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 317  *
 318  * DESCRIPTION: Returns the event_info struct associated with this GPE.
 319  *              Validates the gpe_block and the gpe_number
 320  *
 321  *              Should be called only when the GPE lists are semaphore locked
 322  *              and not subject to change.
 323  *
 324  ******************************************************************************/
 325
 326 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 327                                                        u32 gpe_number)
 328 {
 329         union acpi_operand_object *obj_desc;
 330         struct acpi_gpe_event_info *gpe_info;
 331         u32 i;
 332
 333         ACPI_FUNCTION_ENTRY();
 334
 335         /* A NULL gpe_device means use the FADT-defined GPE block(s) */
 336
 337         if (!gpe_device) {
 338
 339                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 340
 341                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
 342                         gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
 343                                                             acpi_gbl_gpe_fadt_blocks
 344                                                             [i]);
 345                         if (gpe_info) {
 346                                 return (gpe_info);
 347                         }
 348                 }
 349
 350                 /* The gpe_number was not in the range of either FADT GPE block */
 351
 352                 return (NULL);
 353         }
 354
 355         /* A Non-NULL gpe_device means this is a GPE Block Device */
 356
 357         obj_desc =
 358             acpi_ns_get_attached_object((struct acpi_namespace_node *)
 359                                                gpe_device);
 360         if (!obj_desc || !obj_desc->device.gpe_block) {
 361                 return (NULL);
 362         }
 363
 364         return (acpi_ev_low_get_gpe_info
 365                 (gpe_number, obj_desc->device.gpe_block));
 366 }
 367
 368 /*******************************************************************************
 369  *
 370  * FUNCTION:    acpi_ev_gpe_detect
 371  *
 372  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 373  *                                    Can have multiple GPE blocks attached.
 374  *
 375  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 376  *
 377  * DESCRIPTION: Detect if any GP events have occurred. This function is
 378  *              executed at interrupt level.
 379  *
 380  ******************************************************************************/
 381
 382 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info *gpe_xrupt_list)
 383 {
 384         acpi_status status;
 385         struct acpi_gpe_block_info *gpe_block;
 386         struct acpi_namespace_node *gpe_device;
 387         struct acpi_gpe_register_info *gpe_register_info;
 388         struct acpi_gpe_event_info *gpe_event_info;
 389         u32 gpe_number;
 390         struct acpi_gpe_handler_info *gpe_handler_info;
 391         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
 392         u8 enabled_status_byte;
 393         u32 status_reg;
 394         u32 enable_reg;
 395         acpi_cpu_flags flags;
 396         u32 i;
 397         u32 j;
 398
 399         ACPI_FUNCTION_NAME(ev_gpe_detect);
 400
 401         /* Check for the case where there are no GPEs */
 402
 403         if (!gpe_xrupt_list) {
 404                 return (int_status);
 405         }
 406
 407         /*
 408          * We need to obtain the GPE lock for both the data structs and registers
 409          * Note: Not necessary to obtain the hardware lock, since the GPE
 410          * registers are owned by the gpe_lock.
 411          */
 412         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 413
 414         /* Examine all GPE blocks attached to this interrupt level */
 415
 416         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 417         while (gpe_block) {
 418                 gpe_device = gpe_block->node;
 419
 420                 /*
 421                  * Read all of the 8-bit GPE status and enable registers in this GPE
 422                  * block, saving all of them. Find all currently active GP events.
 423                  */
 424                 for (i = 0; i < gpe_block->register_count; i++) {
 425
 426                         /* Get the next status/enable pair */
 427
 428                         gpe_register_info = &gpe_block->register_info[i];
 429
 430                         /*
 431                          * Optimization: If there are no GPEs enabled within this
 432                          * register, we can safely ignore the entire register.
 433                          */
 434                         if (!(gpe_register_info->enable_for_run |
 435                               gpe_register_info->enable_for_wake)) {
 436                                 ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 437                                                   "Ignore disabled registers for GPE %02X-%02X: "
 438                                                   "RunEnable=%02X, WakeEnable=%02X\n",
 439                                                   gpe_register_info->
 440                                                   base_gpe_number,
 441                                                   gpe_register_info->
 442                                                   base_gpe_number +
 443                                                   (ACPI_GPE_REGISTER_WIDTH - 1),
 444                                                   gpe_register_info->
 445                                                   enable_for_run,
 446                                                   gpe_register_info->
 447                                                   enable_for_wake));
 448                                 continue;
 449                         }
 450
 451                         /* Read the Status Register */
 452
 453                         status =
 454                             acpi_hw_read(&status_reg,
 455                                          &gpe_register_info->status_address);
 456                         if (ACPI_FAILURE(status)) {
 457                                 goto unlock_and_exit;
 458                         }
 459
 460                         /* Read the Enable Register */
 461
 462                         status =
 463                             acpi_hw_read(&enable_reg,
 464                                          &gpe_register_info->enable_address);
 465                         if (ACPI_FAILURE(status)) {
 466                                 goto unlock_and_exit;
 467                         }
 468
 469                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 470                                           "Read registers for GPE %02X-%02X: Status=%02X, Enable=%02X, "
 471                                           "RunEnable=%02X, WakeEnable=%02X\n",
 472                                           gpe_register_info->base_gpe_number,
 473                                           gpe_register_info->base_gpe_number +
 474                                           (ACPI_GPE_REGISTER_WIDTH - 1),
 475                                           status_reg, enable_reg,
 476                                           gpe_register_info->enable_for_run,
 477                                           gpe_register_info->enable_for_wake));
 478
 479                         /* Check if there is anything active at all in this register */
 480
 481                         enabled_status_byte = (u8)(status_reg & enable_reg);
 482                         if (!enabled_status_byte) {
 483
 484                                 /* No active GPEs in this register, move on */
 485
 486                                 continue;
 487                         }
 488
 489                         /* Now look at the individual GPEs in this byte register */
 490
 491                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 492
 493                                 /* Examine one GPE bit */
 494
 495                                 gpe_event_info =
 496                                     &gpe_block->
 497                                     event_info[((acpi_size)i *
 498                                                 ACPI_GPE_REGISTER_WIDTH) + j];
 499                                 gpe_number =
 500                                     j + gpe_register_info->base_gpe_number;
 501
 502                                 if (enabled_status_byte & (1 << j)) {
 503
 504                                         /* Invoke global event handler if present */
 505
 506                                         acpi_gpe_count++;
 507                                         if (acpi_gbl_global_event_handler) {
 508                                                 acpi_gbl_global_event_handler
 509                                                     (ACPI_EVENT_TYPE_GPE,
 510                                                      gpe_device, gpe_number,
 511                                                      acpi_gbl_global_event_handler_context);
 512                                         }
 513
 514                                         /* Found an active GPE */
 515
 516                                         if (ACPI_GPE_DISPATCH_TYPE
 517                                             (gpe_event_info->flags) ==
 518                                             ACPI_GPE_DISPATCH_RAW_HANDLER) {
 519
 520                                                 /* Dispatch the event to a raw handler */
 521
 522                                                 gpe_handler_info =
 523                                                     gpe_event_info->dispatch.
 524                                                     handler;
 525
 526                                                 /*
 527                                                  * There is no protection around the namespace node
 528                                                  * and the GPE handler to ensure a safe destruction
 529                                                  * because:
 530                                                  * 1. The namespace node is expected to always
 531                                                  *    exist after loading a table.
 532                                                  * 2. The GPE handler is expected to be flushed by
 533                                                  *    acpi_os_wait_events_complete() before the
 534                                                  *    destruction.
 535                                                  */
 536                                                 acpi_os_release_lock
 537                                                     (acpi_gbl_gpe_lock, flags);
 538                                                 int_status |=
 539                                                     gpe_handler_info->
 540                                                     address(gpe_device,
 541                                                             gpe_number,
 542                                                             gpe_handler_info->
 543                                                             context);
 544                                                 flags =
 545                                                     acpi_os_acquire_lock
 546                                                     (acpi_gbl_gpe_lock);
 547                                         } else {
 548                                                 /*
 549                                                  * Dispatch the event to a standard handler or
 550                                                  * method.
 551                                                  */
 552                                                 int_status |=
 553                                                     acpi_ev_gpe_dispatch
 554                                                     (gpe_device, gpe_event_info,
 555                                                      gpe_number);
 556                                         }
 557                                 }
 558                         }
 559                 }
 560
 561                 gpe_block = gpe_block->next;
 562         }
 563
 564 unlock_and_exit:
 565
 566         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 567         return (int_status);
 568 }
 569
 570 /*******************************************************************************
 571  *
 572  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 573  *
 574  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 575  *
 576  * RETURN:      None
 577  *
 578  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 579  *              function is called from an invocation of acpi_os_execute and
 580  *              therefore does NOT execute at interrupt level - so that
 581  *              the control method itself is not executed in the context of
 582  *              an interrupt handler.
 583  *
 584  ******************************************************************************/
 585
 586 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 587 {
 588         struct acpi_gpe_event_info *gpe_event_info = context;
 589         acpi_status status = AE_OK;
 590         struct acpi_evaluate_info *info;
 591         struct acpi_gpe_notify_info *notify;
 592
 593         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
 594
 595         /* Do the correct dispatch - normal method or implicit notify */
 596
 597         switch (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)) {
 598         case ACPI_GPE_DISPATCH_NOTIFY:
 599                 /*
 600                  * Implicit notify.
 601                  * Dispatch a DEVICE_WAKE notify to the appropriate handler.
 602                  * NOTE: the request is queued for execution after this method
 603                  * completes. The notify handlers are NOT invoked synchronously
 604                  * from this thread -- because handlers may in turn run other
 605                  * control methods.
 606                  *
 607                  * June 2012: Expand implicit notify mechanism to support
 608                  * notifies on multiple device objects.
 609                  */
 610                 notify = gpe_event_info->dispatch.notify_list;
 611                 while (ACPI_SUCCESS(status) && notify) {
 612                         status =
 613                             acpi_ev_queue_notify_request(notify->device_node,
 614                                                          ACPI_NOTIFY_DEVICE_WAKE);
 615
 616                         notify = notify->next;
 617                 }
 618
 619                 break;
 620
 621         case ACPI_GPE_DISPATCH_METHOD:
 622
 623                 /* Allocate the evaluation information block */
 624
 625                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 626                 if (!info) {
 627                         status = AE_NO_MEMORY;
 628                 } else {
 629                         /*
 630                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the
 631                          * _Lxx/_Exx control method that corresponds to this GPE
 632                          */
 633                         info->prefix_node =
 634                             gpe_event_info->dispatch.method_node;
 635                         info->flags = ACPI_IGNORE_RETURN_VALUE;
 636
 637                         status = acpi_ns_evaluate(info);
 638                         ACPI_FREE(info);
 639                 }
 640
 641                 if (ACPI_FAILURE(status)) {
 642                         ACPI_EXCEPTION((AE_INFO, status,
 643                                         "while evaluating GPE method [%4.4s]",
 644                                         acpi_ut_get_node_name(gpe_event_info->
 645                                                               dispatch.
 646                                                               method_node)));
 647                 }
 648                 break;
 649
 650         default:
 651
 652                 goto error_exit;        /* Should never happen */
 653         }
 654
 655         /* Defer enabling of GPE until all notify handlers are done */
 656
 657         status = acpi_os_execute(OSL_NOTIFY_HANDLER,
 658                                  acpi_ev_asynch_enable_gpe, gpe_event_info);
 659         if (ACPI_SUCCESS(status)) {
 660                 return_VOID;
 661         }
 662
 663 error_exit:
 664         acpi_ev_asynch_enable_gpe(gpe_event_info);
 665         return_VOID;
 666 }
 667
 668
 669 /*******************************************************************************
 670  *
 671  * FUNCTION:    acpi_ev_asynch_enable_gpe
 672  *
 673  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 674  *              Callback from acpi_os_execute
 675  *
 676  * RETURN:      None
 677  *
 678  * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
 679  *              complete (i.e., finish execution of Notify)
 680  *
 681  ******************************************************************************/
 682
 683 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context)
 684 {
 685         struct acpi_gpe_event_info *gpe_event_info = context;
 686         acpi_cpu_flags flags;
 687
 688         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 689         (void)acpi_ev_finish_gpe(gpe_event_info);
 690         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 691
 692         return;
 693 }
 694
 695
 696 /*******************************************************************************
 697  *
 698  * FUNCTION:    acpi_ev_finish_gpe
 699  *
 700  * PARAMETERS:  gpe_event_info      - Info for this GPE
 701  *
 702  * RETURN:      Status
 703  *
 704  * DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution
 705  *              of a GPE method or a synchronous or asynchronous GPE handler.
 706  *
 707  ******************************************************************************/
 708
 709 acpi_status acpi_ev_finish_gpe(struct acpi_gpe_event_info *gpe_event_info)
 710 {
 711         acpi_status status;
 712
 713         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 714             ACPI_GPE_LEVEL_TRIGGERED) {
 715                 /*
 716                  * GPE is level-triggered, we clear the GPE status bit after
 717                  * handling the event.
 718                  */
 719                 status = acpi_hw_clear_gpe(gpe_event_info);
 720                 if (ACPI_FAILURE(status)) {
 721                         return (status);
 722                 }
 723         }
 724
 725         /*
 726          * Enable this GPE, conditionally. This means that the GPE will
 727          * only be physically enabled if the enable_mask bit is set
 728          * in the event_info.
 729          */
 730         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_CONDITIONAL_ENABLE);
 731         gpe_event_info->disable_for_dispatch = FALSE;
 732         return (AE_OK);
 733 }
 734
 735
 736 /*******************************************************************************
 737  *
 738  * FUNCTION:    acpi_ev_gpe_dispatch
 739  *
 740  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 741  *              gpe_event_info      - Info for this GPE
 742  *              gpe_number          - Number relative to the parent GPE block
 743  *
 744  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 745  *
 746  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 747  *              or method (e.g. _Lxx/_Exx) handler.
 748  *
 749  *              This function executes at interrupt level.
 750  *
 751  ******************************************************************************/
 752
 753 u32
 754 acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
 755                      struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 756 {
 757         acpi_status status;
 758         u32 return_value;
 759
 760         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 761
 762         /*
 763          * Always disable the GPE so that it does not keep firing before
 764          * any asynchronous activity completes (either from the execution
 765          * of a GPE method or an asynchronous GPE handler.)
 766          *
 767          * If there is no handler or method to run, just disable the
 768          * GPE and leave it disabled permanently to prevent further such
 769          * pointless events from firing.
 770          */
 771         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 772         if (ACPI_FAILURE(status)) {
 773                 ACPI_EXCEPTION((AE_INFO, status,
 774                                 "Unable to disable GPE %02X", gpe_number));
 775                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 776         }
 777
 778         /*
 779          * If edge-triggered, clear the GPE status bit now. Note that
 780          * level-triggered events are cleared after the GPE is serviced.
 781          */
 782         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 783             ACPI_GPE_EDGE_TRIGGERED) {
 784                 status = acpi_hw_clear_gpe(gpe_event_info);
 785                 if (ACPI_FAILURE(status)) {
 786                         ACPI_EXCEPTION((AE_INFO, status,
 787                                         "Unable to clear GPE %02X",
 788                                         gpe_number));
 789                         (void)acpi_hw_low_set_gpe(gpe_event_info,
 790                                                   ACPI_GPE_CONDITIONAL_ENABLE);
 791                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 792                 }
 793         }
 794
 795         gpe_event_info->disable_for_dispatch = TRUE;
 796
 797         /*
 798          * Dispatch the GPE to either an installed handler or the control
 799          * method associated with this GPE (_Lxx or _Exx). If a handler
 800          * exists, we invoke it and do not attempt to run the method.
 801          * If there is neither a handler nor a method, leave the GPE
 802          * disabled.
 803          */
 804         switch (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)) {
 805         case ACPI_GPE_DISPATCH_HANDLER:
 806
 807                 /* Invoke the installed handler (at interrupt level) */
 808
 809                 return_value =
 810                     gpe_event_info->dispatch.handler->address(gpe_device,
 811                                                               gpe_number,
 812                                                               gpe_event_info->
 813                                                               dispatch.handler->
 814                                                               context);
 815
 816                 /* If requested, clear (if level-triggered) and reenable the GPE */
 817
 818                 if (return_value & ACPI_REENABLE_GPE) {
 819                         (void)acpi_ev_finish_gpe(gpe_event_info);
 820                 }
 821                 break;
 822
 823         case ACPI_GPE_DISPATCH_METHOD:
 824         case ACPI_GPE_DISPATCH_NOTIFY:
 825                 /*
 826                  * Execute the method associated with the GPE
 827                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 828                  */
 829                 status = acpi_os_execute(OSL_GPE_HANDLER,
 830                                          acpi_ev_asynch_execute_gpe_method,
 831                                          gpe_event_info);
 832                 if (ACPI_FAILURE(status)) {
 833                         ACPI_EXCEPTION((AE_INFO, status,
 834                                         "Unable to queue handler for GPE %02X - event disabled",
 835                                         gpe_number));
 836                 }
 837                 break;
 838
 839         default:
 840                 /*
 841                  * No handler or method to run!
 842                  * 03/2010: This case should no longer be possible. We will not allow
 843                  * a GPE to be enabled if it has no handler or method.
 844                  */
 845                 ACPI_ERROR((AE_INFO,
 846                             "No handler or method for GPE %02X, disabling event",
 847                             gpe_number));
 848
 849                 break;
 850         }
 851
 852         return_UINT32(ACPI_INTERRUPT_HANDLED);
 853 }
 854
 855 #endif                          /* !ACPI_REDUCED_HARDWARE */