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 - 2014, 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         return_ACPI_STATUS(AE_OK);
  97 }
  98
  99 /*******************************************************************************
 100  *
 101  * FUNCTION:    acpi_ev_enable_gpe
 102  *
 103  * PARAMETERS:  gpe_event_info          - GPE to enable
 104  *
 105  * RETURN:      Status
 106  *
 107  * DESCRIPTION: Clear a GPE of stale events and enable it.
 108  *
 109  ******************************************************************************/
 110
 111 acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
 112 {
 113         acpi_status status;
 114
 115         ACPI_FUNCTION_TRACE(ev_enable_gpe);
 116
 117         /*
 118          * We will only allow a GPE to be enabled if it has either an associated
 119          * method (_Lxx/_Exx) or a handler, or is using the implicit notify
 120          * feature. Otherwise, the GPE will be immediately disabled by
 121          * acpi_ev_gpe_dispatch the first time it fires.
 122          */
 123         if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
 124             ACPI_GPE_DISPATCH_NONE) {
 125                 return_ACPI_STATUS(AE_NO_HANDLER);
 126         }
 127
 128         /* Clear the GPE (of stale events) */
 129
 130         status = acpi_hw_clear_gpe(gpe_event_info);
 131         if (ACPI_FAILURE(status)) {
 132                 return_ACPI_STATUS(status);
 133         }
 134
 135         /* Enable the requested GPE */
 136
 137         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE);
 138         return_ACPI_STATUS(status);
 139 }
 140
 141 /*******************************************************************************
 142  *
 143  * FUNCTION:    acpi_ev_add_gpe_reference
 144  *
 145  * PARAMETERS:  gpe_event_info          - Add a reference to this GPE
 146  *
 147  * RETURN:      Status
 148  *
 149  * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
 150  *              hardware-enabled.
 151  *
 152  ******************************************************************************/
 153
 154 acpi_status
 155 acpi_ev_add_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 156 {
 157         acpi_status status = AE_OK;
 158
 159         ACPI_FUNCTION_TRACE(ev_add_gpe_reference);
 160
 161         if (gpe_event_info->runtime_count == ACPI_UINT8_MAX) {
 162                 return_ACPI_STATUS(AE_LIMIT);
 163         }
 164
 165         gpe_event_info->runtime_count++;
 166         if (gpe_event_info->runtime_count == 1) {
 167
 168                 /* Enable on first reference */
 169
 170                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 171                 if (ACPI_SUCCESS(status)) {
 172                         status = acpi_ev_enable_gpe(gpe_event_info);
 173                 }
 174
 175                 if (ACPI_FAILURE(status)) {
 176                         gpe_event_info->runtime_count--;
 177                 }
 178         }
 179
 180         return_ACPI_STATUS(status);
 181 }
 182
 183 /*******************************************************************************
 184  *
 185  * FUNCTION:    acpi_ev_remove_gpe_reference
 186  *
 187  * PARAMETERS:  gpe_event_info          - Remove a reference to this GPE
 188  *
 189  * RETURN:      Status
 190  *
 191  * DESCRIPTION: Remove a reference to a GPE. When the last reference is
 192  *              removed, the GPE is hardware-disabled.
 193  *
 194  ******************************************************************************/
 195
 196 acpi_status
 197 acpi_ev_remove_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 198 {
 199         acpi_status status = AE_OK;
 200
 201         ACPI_FUNCTION_TRACE(ev_remove_gpe_reference);
 202
 203         if (!gpe_event_info->runtime_count) {
 204                 return_ACPI_STATUS(AE_LIMIT);
 205         }
 206
 207         gpe_event_info->runtime_count--;
 208         if (!gpe_event_info->runtime_count) {
 209
 210                 /* Disable on last reference */
 211
 212                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 213                 if (ACPI_SUCCESS(status)) {
 214                         status =
 215                             acpi_hw_low_set_gpe(gpe_event_info,
 216                                                 ACPI_GPE_DISABLE);
 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_low_get_gpe_info
 230  *
 231  * PARAMETERS:  gpe_number          - Raw GPE number
 232  *              gpe_block           - A GPE info block
 233  *
 234  * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
 235  *              is not within the specified GPE block)
 236  *
 237  * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
 238  *              the low-level implementation of ev_get_gpe_event_info.
 239  *
 240  ******************************************************************************/
 241
 242 struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
 243                                                      struct acpi_gpe_block_info
 244                                                      *gpe_block)
 245 {
 246         u32 gpe_index;
 247
 248         /*
 249          * Validate that the gpe_number is within the specified gpe_block.
 250          * (Two steps)
 251          */
 252         if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
 253                 return (NULL);
 254         }
 255
 256         gpe_index = gpe_number - gpe_block->block_base_number;
 257         if (gpe_index >= gpe_block->gpe_count) {
 258                 return (NULL);
 259         }
 260
 261         return (&gpe_block->event_info[gpe_index]);
 262 }
 263
 264
 265 /*******************************************************************************
 266  *
 267  * FUNCTION:    acpi_ev_get_gpe_event_info
 268  *
 269  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 270  *              gpe_number          - Raw GPE number
 271  *
 272  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 273  *
 274  * DESCRIPTION: Returns the event_info struct associated with this GPE.
 275  *              Validates the gpe_block and the gpe_number
 276  *
 277  *              Should be called only when the GPE lists are semaphore locked
 278  *              and not subject to change.
 279  *
 280  ******************************************************************************/
 281
 282 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 283                                                        u32 gpe_number)
 284 {
 285         union acpi_operand_object *obj_desc;
 286         struct acpi_gpe_event_info *gpe_info;
 287         u32 i;
 288
 289         ACPI_FUNCTION_ENTRY();
 290
 291         /* A NULL gpe_device means use the FADT-defined GPE block(s) */
 292
 293         if (!gpe_device) {
 294
 295                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 296
 297                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
 298                         gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
 299                                                             acpi_gbl_gpe_fadt_blocks
 300                                                             [i]);
 301                         if (gpe_info) {
 302                                 return (gpe_info);
 303                         }
 304                 }
 305
 306                 /* The gpe_number was not in the range of either FADT GPE block */
 307
 308                 return (NULL);
 309         }
 310
 311         /* A Non-NULL gpe_device means this is a GPE Block Device */
 312
 313         obj_desc =
 314             acpi_ns_get_attached_object((struct acpi_namespace_node *)
 315                                                gpe_device);
 316         if (!obj_desc || !obj_desc->device.gpe_block) {
 317                 return (NULL);
 318         }
 319
 320         return (acpi_ev_low_get_gpe_info
 321                 (gpe_number, obj_desc->device.gpe_block));
 322 }
 323
 324 /*******************************************************************************
 325  *
 326  * FUNCTION:    acpi_ev_gpe_detect
 327  *
 328  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 329  *                                    Can have multiple GPE blocks attached.
 330  *
 331  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 332  *
 333  * DESCRIPTION: Detect if any GP events have occurred. This function is
 334  *              executed at interrupt level.
 335  *
 336  ******************************************************************************/
 337
 338 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info *gpe_xrupt_list)
 339 {
 340         acpi_status status;
 341         struct acpi_gpe_block_info *gpe_block;
 342         struct acpi_gpe_register_info *gpe_register_info;
 343         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
 344         u8 enabled_status_byte;
 345         u32 status_reg;
 346         u32 enable_reg;
 347         acpi_cpu_flags flags;
 348         u32 i;
 349         u32 j;
 350
 351         ACPI_FUNCTION_NAME(ev_gpe_detect);
 352
 353         /* Check for the case where there are no GPEs */
 354
 355         if (!gpe_xrupt_list) {
 356                 return (int_status);
 357         }
 358
 359         /*
 360          * We need to obtain the GPE lock for both the data structs and registers
 361          * Note: Not necessary to obtain the hardware lock, since the GPE
 362          * registers are owned by the gpe_lock.
 363          */
 364         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 365
 366         /* Examine all GPE blocks attached to this interrupt level */
 367
 368         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 369         while (gpe_block) {
 370                 /*
 371                  * Read all of the 8-bit GPE status and enable registers in this GPE
 372                  * block, saving all of them. Find all currently active GP events.
 373                  */
 374                 for (i = 0; i < gpe_block->register_count; i++) {
 375
 376                         /* Get the next status/enable pair */
 377
 378                         gpe_register_info = &gpe_block->register_info[i];
 379
 380                         /*
 381                          * Optimization: If there are no GPEs enabled within this
 382                          * register, we can safely ignore the entire register.
 383                          */
 384                         if (!(gpe_register_info->enable_for_run |
 385                               gpe_register_info->enable_for_wake)) {
 386                                 ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 387                                                   "Ignore disabled registers for GPE %02X-%02X: "
 388                                                   "RunEnable=%02X, WakeEnable=%02X\n",
 389                                                   gpe_register_info->
 390                                                   base_gpe_number,
 391                                                   gpe_register_info->
 392                                                   base_gpe_number +
 393                                                   (ACPI_GPE_REGISTER_WIDTH - 1),
 394                                                   gpe_register_info->
 395                                                   enable_for_run,
 396                                                   gpe_register_info->
 397                                                   enable_for_wake));
 398                                 continue;
 399                         }
 400
 401                         /* Read the Status Register */
 402
 403                         status =
 404                             acpi_hw_read(&status_reg,
 405                                          &gpe_register_info->status_address);
 406                         if (ACPI_FAILURE(status)) {
 407                                 goto unlock_and_exit;
 408                         }
 409
 410                         /* Read the Enable Register */
 411
 412                         status =
 413                             acpi_hw_read(&enable_reg,
 414                                          &gpe_register_info->enable_address);
 415                         if (ACPI_FAILURE(status)) {
 416                                 goto unlock_and_exit;
 417                         }
 418
 419                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 420                                           "Read registers for GPE %02X-%02X: Status=%02X, Enable=%02X, "
 421                                           "RunEnable=%02X, WakeEnable=%02X\n",
 422                                           gpe_register_info->base_gpe_number,
 423                                           gpe_register_info->base_gpe_number +
 424                                           (ACPI_GPE_REGISTER_WIDTH - 1),
 425                                           status_reg, enable_reg,
 426                                           gpe_register_info->enable_for_run,
 427                                           gpe_register_info->enable_for_wake));
 428
 429                         /* Check if there is anything active at all in this register */
 430
 431                         enabled_status_byte = (u8)(status_reg & enable_reg);
 432                         if (!enabled_status_byte) {
 433
 434                                 /* No active GPEs in this register, move on */
 435
 436                                 continue;
 437                         }
 438
 439                         /* Now look at the individual GPEs in this byte register */
 440
 441                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 442
 443                                 /* Examine one GPE bit */
 444
 445                                 if (enabled_status_byte & (1 << j)) {
 446                                         /*
 447                                          * Found an active GPE. Dispatch the event to a handler
 448                                          * or method.
 449                                          */
 450                                         int_status |=
 451                                             acpi_ev_gpe_dispatch(gpe_block->
 452                                                                  node,
 453                                                                  &gpe_block->
 454                                                                  event_info[((acpi_size) i * ACPI_GPE_REGISTER_WIDTH) + j], j + gpe_register_info->base_gpe_number);
 455                                 }
 456                         }
 457                 }
 458
 459                 gpe_block = gpe_block->next;
 460         }
 461
 462 unlock_and_exit:
 463
 464         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 465         return (int_status);
 466 }
 467
 468 /*******************************************************************************
 469  *
 470  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 471  *
 472  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 473  *
 474  * RETURN:      None
 475  *
 476  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 477  *              function is called from an invocation of acpi_os_execute and
 478  *              therefore does NOT execute at interrupt level - so that
 479  *              the control method itself is not executed in the context of
 480  *              an interrupt handler.
 481  *
 482  ******************************************************************************/
 483
 484 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 485 {
 486         struct acpi_gpe_event_info *gpe_event_info = context;
 487         acpi_status status;
 488         struct acpi_gpe_event_info *local_gpe_event_info;
 489         struct acpi_evaluate_info *info;
 490         struct acpi_gpe_notify_info *notify;
 491
 492         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
 493
 494         /* Allocate a local GPE block */
 495
 496         local_gpe_event_info =
 497             ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_event_info));
 498         if (!local_gpe_event_info) {
 499                 ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY, "while handling a GPE"));
 500                 return_VOID;
 501         }
 502
 503         status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
 504         if (ACPI_FAILURE(status)) {
 505                 ACPI_FREE(local_gpe_event_info);
 506                 return_VOID;
 507         }
 508
 509         /* Must revalidate the gpe_number/gpe_block */
 510
 511         if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
 512                 status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 513                 ACPI_FREE(local_gpe_event_info);
 514                 return_VOID;
 515         }
 516
 517         /*
 518          * Take a snapshot of the GPE info for this level - we copy the info to
 519          * prevent a race condition with remove_handler/remove_block.
 520          */
 521         ACPI_MEMCPY(local_gpe_event_info, gpe_event_info,
 522                     sizeof(struct acpi_gpe_event_info));
 523
 524         status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
 525         if (ACPI_FAILURE(status)) {
 526                 ACPI_FREE(local_gpe_event_info);
 527                 return_VOID;
 528         }
 529
 530         /* Do the correct dispatch - normal method or implicit notify */
 531
 532         switch (local_gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
 533         case ACPI_GPE_DISPATCH_NOTIFY:
 534                 /*
 535                  * Implicit notify.
 536                  * Dispatch a DEVICE_WAKE notify to the appropriate handler.
 537                  * NOTE: the request is queued for execution after this method
 538                  * completes. The notify handlers are NOT invoked synchronously
 539                  * from this thread -- because handlers may in turn run other
 540                  * control methods.
 541                  *
 542                  * June 2012: Expand implicit notify mechanism to support
 543                  * notifies on multiple device objects.
 544                  */
 545                 notify = local_gpe_event_info->dispatch.notify_list;
 546                 while (ACPI_SUCCESS(status) && notify) {
 547                         status =
 548                             acpi_ev_queue_notify_request(notify->device_node,
 549                                                          ACPI_NOTIFY_DEVICE_WAKE);
 550
 551                         notify = notify->next;
 552                 }
 553
 554                 break;
 555
 556         case ACPI_GPE_DISPATCH_METHOD:
 557
 558                 /* Allocate the evaluation information block */
 559
 560                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 561                 if (!info) {
 562                         status = AE_NO_MEMORY;
 563                 } else {
 564                         /*
 565                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the
 566                          * _Lxx/_Exx control method that corresponds to this GPE
 567                          */
 568                         info->prefix_node =
 569                             local_gpe_event_info->dispatch.method_node;
 570                         info->flags = ACPI_IGNORE_RETURN_VALUE;
 571
 572                         status = acpi_ns_evaluate(info);
 573                         ACPI_FREE(info);
 574                 }
 575
 576                 if (ACPI_FAILURE(status)) {
 577                         ACPI_EXCEPTION((AE_INFO, status,
 578                                         "while evaluating GPE method [%4.4s]",
 579                                         acpi_ut_get_node_name
 580                                         (local_gpe_event_info->dispatch.
 581                                          method_node)));
 582                 }
 583                 break;
 584
 585         default:
 586
 587                 return_VOID;    /* Should never happen */
 588         }
 589
 590         /* Defer enabling of GPE until all notify handlers are done */
 591
 592         status = acpi_os_execute(OSL_NOTIFY_HANDLER,
 593                                  acpi_ev_asynch_enable_gpe,
 594                                  local_gpe_event_info);
 595         if (ACPI_FAILURE(status)) {
 596                 ACPI_FREE(local_gpe_event_info);
 597         }
 598         return_VOID;
 599 }
 600
 601
 602 /*******************************************************************************
 603  *
 604  * FUNCTION:    acpi_ev_asynch_enable_gpe
 605  *
 606  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 607  *              Callback from acpi_os_execute
 608  *
 609  * RETURN:      None
 610  *
 611  * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
 612  *              complete (i.e., finish execution of Notify)
 613  *
 614  ******************************************************************************/
 615
 616 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context)
 617 {
 618         struct acpi_gpe_event_info *gpe_event_info = context;
 619
 620         (void)acpi_ev_finish_gpe(gpe_event_info);
 621
 622         ACPI_FREE(gpe_event_info);
 623         return;
 624 }
 625
 626
 627 /*******************************************************************************
 628  *
 629  * FUNCTION:    acpi_ev_finish_gpe
 630  *
 631  * PARAMETERS:  gpe_event_info      - Info for this GPE
 632  *
 633  * RETURN:      Status
 634  *
 635  * DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution
 636  *              of a GPE method or a synchronous or asynchronous GPE handler.
 637  *
 638  ******************************************************************************/
 639
 640 acpi_status acpi_ev_finish_gpe(struct acpi_gpe_event_info * gpe_event_info)
 641 {
 642         acpi_status status;
 643
 644         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 645             ACPI_GPE_LEVEL_TRIGGERED) {
 646                 /*
 647                  * GPE is level-triggered, we clear the GPE status bit after
 648                  * handling the event.
 649                  */
 650                 status = acpi_hw_clear_gpe(gpe_event_info);
 651                 if (ACPI_FAILURE(status)) {
 652                         return (status);
 653                 }
 654         }
 655
 656         /*
 657          * Enable this GPE, conditionally. This means that the GPE will
 658          * only be physically enabled if the enable_for_run bit is set
 659          * in the event_info.
 660          */
 661         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_CONDITIONAL_ENABLE);
 662         return (AE_OK);
 663 }
 664
 665
 666 /*******************************************************************************
 667  *
 668  * FUNCTION:    acpi_ev_gpe_dispatch
 669  *
 670  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 671  *              gpe_event_info      - Info for this GPE
 672  *              gpe_number          - Number relative to the parent GPE block
 673  *
 674  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 675  *
 676  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 677  *              or method (e.g. _Lxx/_Exx) handler.
 678  *
 679  *              This function executes at interrupt level.
 680  *
 681  ******************************************************************************/
 682
 683 u32
 684 acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
 685                      struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 686 {
 687         acpi_status status;
 688         u32 return_value;
 689
 690         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 691
 692         /* Invoke global event handler if present */
 693
 694         acpi_gpe_count++;
 695         if (acpi_gbl_global_event_handler) {
 696                 acpi_gbl_global_event_handler(ACPI_EVENT_TYPE_GPE, gpe_device,
 697                                               gpe_number,
 698                                               acpi_gbl_global_event_handler_context);
 699         }
 700
 701         /*
 702          * Always disable the GPE so that it does not keep firing before
 703          * any asynchronous activity completes (either from the execution
 704          * of a GPE method or an asynchronous GPE handler.)
 705          *
 706          * If there is no handler or method to run, just disable the
 707          * GPE and leave it disabled permanently to prevent further such
 708          * pointless events from firing.
 709          */
 710         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 711         if (ACPI_FAILURE(status)) {
 712                 ACPI_EXCEPTION((AE_INFO, status,
 713                                 "Unable to disable GPE %02X", gpe_number));
 714                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 715         }
 716
 717         /*
 718          * If edge-triggered, clear the GPE status bit now. Note that
 719          * level-triggered events are cleared after the GPE is serviced.
 720          */
 721         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 722             ACPI_GPE_EDGE_TRIGGERED) {
 723                 status = acpi_hw_clear_gpe(gpe_event_info);
 724                 if (ACPI_FAILURE(status)) {
 725                         ACPI_EXCEPTION((AE_INFO, status,
 726                                         "Unable to clear GPE %02X",
 727                                         gpe_number));
 728                         (void)acpi_hw_low_set_gpe(gpe_event_info,
 729                                                   ACPI_GPE_CONDITIONAL_ENABLE);
 730                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 731                 }
 732         }
 733
 734         /*
 735          * Dispatch the GPE to either an installed handler or the control
 736          * method associated with this GPE (_Lxx or _Exx). If a handler
 737          * exists, we invoke it and do not attempt to run the method.
 738          * If there is neither a handler nor a method, leave the GPE
 739          * disabled.
 740          */
 741         switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
 742         case ACPI_GPE_DISPATCH_HANDLER:
 743
 744                 /* Invoke the installed handler (at interrupt level) */
 745
 746                 return_value =
 747                     gpe_event_info->dispatch.handler->address(gpe_device,
 748                                                               gpe_number,
 749                                                               gpe_event_info->
 750                                                               dispatch.handler->
 751                                                               context);
 752
 753                 /* If requested, clear (if level-triggered) and reenable the GPE */
 754
 755                 if (return_value & ACPI_REENABLE_GPE) {
 756                         (void)acpi_ev_finish_gpe(gpe_event_info);
 757                 }
 758                 break;
 759
 760         case ACPI_GPE_DISPATCH_METHOD:
 761         case ACPI_GPE_DISPATCH_NOTIFY:
 762                 /*
 763                  * Execute the method associated with the GPE
 764                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 765                  */
 766                 status = acpi_os_execute(OSL_GPE_HANDLER,
 767                                          acpi_ev_asynch_execute_gpe_method,
 768                                          gpe_event_info);
 769                 if (ACPI_FAILURE(status)) {
 770                         ACPI_EXCEPTION((AE_INFO, status,
 771                                         "Unable to queue handler for GPE %02X - event disabled",
 772                                         gpe_number));
 773                 }
 774                 break;
 775
 776         default:
 777                 /*
 778                  * No handler or method to run!
 779                  * 03/2010: This case should no longer be possible. We will not allow
 780                  * a GPE to be enabled if it has no handler or method.
 781                  */
 782                 ACPI_ERROR((AE_INFO,
 783                             "No handler or method for GPE %02X, disabling event",
 784                             gpe_number));
 785
 786                 break;
 787         }
 788
 789         return_UINT32(ACPI_INTERRUPT_HANDLED);
 790 }
 791
 792 #endif                          /* !ACPI_REDUCED_HARDWARE */