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 - 2015, 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         /* Clear the GPE (of stale events) */
 118
 119         status = acpi_hw_clear_gpe(gpe_event_info);
 120         if (ACPI_FAILURE(status)) {
 121                 return_ACPI_STATUS(status);
 122         }
 123
 124         /* Enable the requested GPE */
 125
 126         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE_SAVE);
 127         return_ACPI_STATUS(status);
 128 }
 129
 130 /*******************************************************************************
 131  *
 132  * FUNCTION:    acpi_ev_add_gpe_reference
 133  *
 134  * PARAMETERS:  gpe_event_info          - Add a reference to this GPE
 135  *
 136  * RETURN:      Status
 137  *
 138  * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
 139  *              hardware-enabled.
 140  *
 141  ******************************************************************************/
 142
 143 acpi_status
 144 acpi_ev_add_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 145 {
 146         acpi_status status = AE_OK;
 147
 148         ACPI_FUNCTION_TRACE(ev_add_gpe_reference);
 149
 150         if (gpe_event_info->runtime_count == ACPI_UINT8_MAX) {
 151                 return_ACPI_STATUS(AE_LIMIT);
 152         }
 153
 154         gpe_event_info->runtime_count++;
 155         if (gpe_event_info->runtime_count == 1) {
 156
 157                 /* Enable on first reference */
 158
 159                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 160                 if (ACPI_SUCCESS(status)) {
 161                         status = acpi_ev_enable_gpe(gpe_event_info);
 162                 }
 163
 164                 if (ACPI_FAILURE(status)) {
 165                         gpe_event_info->runtime_count--;
 166                 }
 167         }
 168
 169         return_ACPI_STATUS(status);
 170 }
 171
 172 /*******************************************************************************
 173  *
 174  * FUNCTION:    acpi_ev_remove_gpe_reference
 175  *
 176  * PARAMETERS:  gpe_event_info          - Remove a reference to this GPE
 177  *
 178  * RETURN:      Status
 179  *
 180  * DESCRIPTION: Remove a reference to a GPE. When the last reference is
 181  *              removed, the GPE is hardware-disabled.
 182  *
 183  ******************************************************************************/
 184
 185 acpi_status
 186 acpi_ev_remove_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
 187 {
 188         acpi_status status = AE_OK;
 189
 190         ACPI_FUNCTION_TRACE(ev_remove_gpe_reference);
 191
 192         if (!gpe_event_info->runtime_count) {
 193                 return_ACPI_STATUS(AE_LIMIT);
 194         }
 195
 196         gpe_event_info->runtime_count--;
 197         if (!gpe_event_info->runtime_count) {
 198
 199                 /* Disable on last reference */
 200
 201                 status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
 202                 if (ACPI_SUCCESS(status)) {
 203                         status =
 204                             acpi_hw_low_set_gpe(gpe_event_info,
 205                                                 ACPI_GPE_DISABLE_SAVE);
 206                 }
 207
 208                 if (ACPI_FAILURE(status)) {
 209                         gpe_event_info->runtime_count++;
 210                 }
 211         }
 212
 213         return_ACPI_STATUS(status);
 214 }
 215
 216 /*******************************************************************************
 217  *
 218  * FUNCTION:    acpi_ev_low_get_gpe_info
 219  *
 220  * PARAMETERS:  gpe_number          - Raw GPE number
 221  *              gpe_block           - A GPE info block
 222  *
 223  * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
 224  *              is not within the specified GPE block)
 225  *
 226  * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
 227  *              the low-level implementation of ev_get_gpe_event_info.
 228  *
 229  ******************************************************************************/
 230
 231 struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
 232                                                      struct acpi_gpe_block_info
 233                                                      *gpe_block)
 234 {
 235         u32 gpe_index;
 236
 237         /*
 238          * Validate that the gpe_number is within the specified gpe_block.
 239          * (Two steps)
 240          */
 241         if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
 242                 return (NULL);
 243         }
 244
 245         gpe_index = gpe_number - gpe_block->block_base_number;
 246         if (gpe_index >= gpe_block->gpe_count) {
 247                 return (NULL);
 248         }
 249
 250         return (&gpe_block->event_info[gpe_index]);
 251 }
 252
 253
 254 /*******************************************************************************
 255  *
 256  * FUNCTION:    acpi_ev_get_gpe_event_info
 257  *
 258  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 259  *              gpe_number          - Raw GPE number
 260  *
 261  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 262  *
 263  * DESCRIPTION: Returns the event_info struct associated with this GPE.
 264  *              Validates the gpe_block and the gpe_number
 265  *
 266  *              Should be called only when the GPE lists are semaphore locked
 267  *              and not subject to change.
 268  *
 269  ******************************************************************************/
 270
 271 struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
 272                                                        u32 gpe_number)
 273 {
 274         union acpi_operand_object *obj_desc;
 275         struct acpi_gpe_event_info *gpe_info;
 276         u32 i;
 277
 278         ACPI_FUNCTION_ENTRY();
 279
 280         /* A NULL gpe_device means use the FADT-defined GPE block(s) */
 281
 282         if (!gpe_device) {
 283
 284                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
 285
 286                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
 287                         gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
 288                                                             acpi_gbl_gpe_fadt_blocks
 289                                                             [i]);
 290                         if (gpe_info) {
 291                                 return (gpe_info);
 292                         }
 293                 }
 294
 295                 /* The gpe_number was not in the range of either FADT GPE block */
 296
 297                 return (NULL);
 298         }
 299
 300         /* A Non-NULL gpe_device means this is a GPE Block Device */
 301
 302         obj_desc =
 303             acpi_ns_get_attached_object((struct acpi_namespace_node *)
 304                                                gpe_device);
 305         if (!obj_desc || !obj_desc->device.gpe_block) {
 306                 return (NULL);
 307         }
 308
 309         return (acpi_ev_low_get_gpe_info
 310                 (gpe_number, obj_desc->device.gpe_block));
 311 }
 312
 313 /*******************************************************************************
 314  *
 315  * FUNCTION:    acpi_ev_gpe_detect
 316  *
 317  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 318  *                                    Can have multiple GPE blocks attached.
 319  *
 320  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 321  *
 322  * DESCRIPTION: Detect if any GP events have occurred. This function is
 323  *              executed at interrupt level.
 324  *
 325  ******************************************************************************/
 326
 327 u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info *gpe_xrupt_list)
 328 {
 329         acpi_status status;
 330         struct acpi_gpe_block_info *gpe_block;
 331         struct acpi_namespace_node *gpe_device;
 332         struct acpi_gpe_register_info *gpe_register_info;
 333         struct acpi_gpe_event_info *gpe_event_info;
 334         u32 gpe_number;
 335         struct acpi_gpe_handler_info *gpe_handler_info;
 336         u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
 337         u8 enabled_status_byte;
 338         u32 status_reg;
 339         u32 enable_reg;
 340         acpi_cpu_flags flags;
 341         u32 i;
 342         u32 j;
 343
 344         ACPI_FUNCTION_NAME(ev_gpe_detect);
 345
 346         /* Check for the case where there are no GPEs */
 347
 348         if (!gpe_xrupt_list) {
 349                 return (int_status);
 350         }
 351
 352         /*
 353          * We need to obtain the GPE lock for both the data structs and registers
 354          * Note: Not necessary to obtain the hardware lock, since the GPE
 355          * registers are owned by the gpe_lock.
 356          */
 357         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 358
 359         /* Examine all GPE blocks attached to this interrupt level */
 360
 361         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 362         while (gpe_block) {
 363                 gpe_device = gpe_block->node;
 364
 365                 /*
 366                  * Read all of the 8-bit GPE status and enable registers in this GPE
 367                  * block, saving all of them. Find all currently active GP events.
 368                  */
 369                 for (i = 0; i < gpe_block->register_count; i++) {
 370
 371                         /* Get the next status/enable pair */
 372
 373                         gpe_register_info = &gpe_block->register_info[i];
 374
 375                         /*
 376                          * Optimization: If there are no GPEs enabled within this
 377                          * register, we can safely ignore the entire register.
 378                          */
 379                         if (!(gpe_register_info->enable_for_run |
 380                               gpe_register_info->enable_for_wake)) {
 381                                 ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 382                                                   "Ignore disabled registers for GPE %02X-%02X: "
 383                                                   "RunEnable=%02X, WakeEnable=%02X\n",
 384                                                   gpe_register_info->
 385                                                   base_gpe_number,
 386                                                   gpe_register_info->
 387                                                   base_gpe_number +
 388                                                   (ACPI_GPE_REGISTER_WIDTH - 1),
 389                                                   gpe_register_info->
 390                                                   enable_for_run,
 391                                                   gpe_register_info->
 392                                                   enable_for_wake));
 393                                 continue;
 394                         }
 395
 396                         /* Read the Status Register */
 397
 398                         status =
 399                             acpi_hw_read(&status_reg,
 400                                          &gpe_register_info->status_address);
 401                         if (ACPI_FAILURE(status)) {
 402                                 goto unlock_and_exit;
 403                         }
 404
 405                         /* Read the Enable Register */
 406
 407                         status =
 408                             acpi_hw_read(&enable_reg,
 409                                          &gpe_register_info->enable_address);
 410                         if (ACPI_FAILURE(status)) {
 411                                 goto unlock_and_exit;
 412                         }
 413
 414                         ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
 415                                           "Read registers for GPE %02X-%02X: Status=%02X, Enable=%02X, "
 416                                           "RunEnable=%02X, WakeEnable=%02X\n",
 417                                           gpe_register_info->base_gpe_number,
 418                                           gpe_register_info->base_gpe_number +
 419                                           (ACPI_GPE_REGISTER_WIDTH - 1),
 420                                           status_reg, enable_reg,
 421                                           gpe_register_info->enable_for_run,
 422                                           gpe_register_info->enable_for_wake));
 423
 424                         /* Check if there is anything active at all in this register */
 425
 426                         enabled_status_byte = (u8)(status_reg & enable_reg);
 427                         if (!enabled_status_byte) {
 428
 429                                 /* No active GPEs in this register, move on */
 430
 431                                 continue;
 432                         }
 433
 434                         /* Now look at the individual GPEs in this byte register */
 435
 436                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 437
 438                                 /* Examine one GPE bit */
 439
 440                                 gpe_event_info =
 441                                     &gpe_block->
 442                                     event_info[((acpi_size) i *
 443                                                 ACPI_GPE_REGISTER_WIDTH) + j];
 444                                 gpe_number =
 445                                     j + gpe_register_info->base_gpe_number;
 446
 447                                 if (enabled_status_byte & (1 << j)) {
 448
 449                                         /* Invoke global event handler if present */
 450
 451                                         acpi_gpe_count++;
 452                                         if (acpi_gbl_global_event_handler) {
 453                                                 acpi_gbl_global_event_handler
 454                                                     (ACPI_EVENT_TYPE_GPE,
 455                                                      gpe_device, gpe_number,
 456                                                      acpi_gbl_global_event_handler_context);
 457                                         }
 458
 459                                         /* Found an active GPE */
 460
 461                                         if (ACPI_GPE_DISPATCH_TYPE
 462                                             (gpe_event_info->flags) ==
 463                                             ACPI_GPE_DISPATCH_RAW_HANDLER) {
 464
 465                                                 /* Dispatch the event to a raw handler */
 466
 467                                                 gpe_handler_info =
 468                                                     gpe_event_info->dispatch.
 469                                                     handler;
 470
 471                                                 /*
 472                                                  * There is no protection around the namespace node
 473                                                  * and the GPE handler to ensure a safe destruction
 474                                                  * because:
 475                                                  * 1. The namespace node is expected to always
 476                                                  *    exist after loading a table.
 477                                                  * 2. The GPE handler is expected to be flushed by
 478                                                  *    acpi_os_wait_events_complete() before the
 479                                                  *    destruction.
 480                                                  */
 481                                                 acpi_os_release_lock
 482                                                     (acpi_gbl_gpe_lock, flags);
 483                                                 int_status |=
 484                                                     gpe_handler_info->
 485                                                     address(gpe_device,
 486                                                             gpe_number,
 487                                                             gpe_handler_info->
 488                                                             context);
 489                                                 flags =
 490                                                     acpi_os_acquire_lock
 491                                                     (acpi_gbl_gpe_lock);
 492                                         } else {
 493                                                 /*
 494                                                  * Dispatch the event to a standard handler or
 495                                                  * method.
 496                                                  */
 497                                                 int_status |=
 498                                                     acpi_ev_gpe_dispatch
 499                                                     (gpe_device, gpe_event_info,
 500                                                      gpe_number);
 501                                         }
 502                                 }
 503                         }
 504                 }
 505
 506                 gpe_block = gpe_block->next;
 507         }
 508
 509 unlock_and_exit:
 510
 511         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 512         return (int_status);
 513 }
 514
 515 /*******************************************************************************
 516  *
 517  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 518  *
 519  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 520  *
 521  * RETURN:      None
 522  *
 523  * DESCRIPTION: Perform the actual execution of a GPE control method. This
 524  *              function is called from an invocation of acpi_os_execute and
 525  *              therefore does NOT execute at interrupt level - so that
 526  *              the control method itself is not executed in the context of
 527  *              an interrupt handler.
 528  *
 529  ******************************************************************************/
 530
 531 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
 532 {
 533         struct acpi_gpe_event_info *gpe_event_info = context;
 534         acpi_status status = AE_OK;
 535         struct acpi_evaluate_info *info;
 536         struct acpi_gpe_notify_info *notify;
 537
 538         ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);
 539
 540         /* Do the correct dispatch - normal method or implicit notify */
 541
 542         switch (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)) {
 543         case ACPI_GPE_DISPATCH_NOTIFY:
 544                 /*
 545                  * Implicit notify.
 546                  * Dispatch a DEVICE_WAKE notify to the appropriate handler.
 547                  * NOTE: the request is queued for execution after this method
 548                  * completes. The notify handlers are NOT invoked synchronously
 549                  * from this thread -- because handlers may in turn run other
 550                  * control methods.
 551                  *
 552                  * June 2012: Expand implicit notify mechanism to support
 553                  * notifies on multiple device objects.
 554                  */
 555                 notify = gpe_event_info->dispatch.notify_list;
 556                 while (ACPI_SUCCESS(status) && notify) {
 557                         status =
 558                             acpi_ev_queue_notify_request(notify->device_node,
 559                                                          ACPI_NOTIFY_DEVICE_WAKE);
 560
 561                         notify = notify->next;
 562                 }
 563
 564                 break;
 565
 566         case ACPI_GPE_DISPATCH_METHOD:
 567
 568                 /* Allocate the evaluation information block */
 569
 570                 info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
 571                 if (!info) {
 572                         status = AE_NO_MEMORY;
 573                 } else {
 574                         /*
 575                          * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the
 576                          * _Lxx/_Exx control method that corresponds to this GPE
 577                          */
 578                         info->prefix_node =
 579                             gpe_event_info->dispatch.method_node;
 580                         info->flags = ACPI_IGNORE_RETURN_VALUE;
 581
 582                         status = acpi_ns_evaluate(info);
 583                         ACPI_FREE(info);
 584                 }
 585
 586                 if (ACPI_FAILURE(status)) {
 587                         ACPI_EXCEPTION((AE_INFO, status,
 588                                         "while evaluating GPE method [%4.4s]",
 589                                         acpi_ut_get_node_name(gpe_event_info->
 590                                                               dispatch.
 591                                                               method_node)));
 592                 }
 593                 break;
 594
 595         default:
 596
 597                 goto error_exit;        /* Should never happen */
 598         }
 599
 600         /* Defer enabling of GPE until all notify handlers are done */
 601
 602         status = acpi_os_execute(OSL_NOTIFY_HANDLER,
 603                                  acpi_ev_asynch_enable_gpe, gpe_event_info);
 604         if (ACPI_SUCCESS(status)) {
 605                 return_VOID;
 606         }
 607
 608 error_exit:
 609         acpi_ev_asynch_enable_gpe(gpe_event_info);
 610         return_VOID;
 611 }
 612
 613
 614 /*******************************************************************************
 615  *
 616  * FUNCTION:    acpi_ev_asynch_enable_gpe
 617  *
 618  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 619  *              Callback from acpi_os_execute
 620  *
 621  * RETURN:      None
 622  *
 623  * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
 624  *              complete (i.e., finish execution of Notify)
 625  *
 626  ******************************************************************************/
 627
 628 static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context)
 629 {
 630         struct acpi_gpe_event_info *gpe_event_info = context;
 631         acpi_cpu_flags flags;
 632
 633         flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);
 634         (void)acpi_ev_finish_gpe(gpe_event_info);
 635         acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
 636
 637         return;
 638 }
 639
 640
 641 /*******************************************************************************
 642  *
 643  * FUNCTION:    acpi_ev_finish_gpe
 644  *
 645  * PARAMETERS:  gpe_event_info      - Info for this GPE
 646  *
 647  * RETURN:      Status
 648  *
 649  * DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution
 650  *              of a GPE method or a synchronous or asynchronous GPE handler.
 651  *
 652  ******************************************************************************/
 653
 654 acpi_status acpi_ev_finish_gpe(struct acpi_gpe_event_info * gpe_event_info)
 655 {
 656         acpi_status status;
 657
 658         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 659             ACPI_GPE_LEVEL_TRIGGERED) {
 660                 /*
 661                  * GPE is level-triggered, we clear the GPE status bit after
 662                  * handling the event.
 663                  */
 664                 status = acpi_hw_clear_gpe(gpe_event_info);
 665                 if (ACPI_FAILURE(status)) {
 666                         return (status);
 667                 }
 668         }
 669
 670         /*
 671          * Enable this GPE, conditionally. This means that the GPE will
 672          * only be physically enabled if the enable_mask bit is set
 673          * in the event_info.
 674          */
 675         (void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_CONDITIONAL_ENABLE);
 676         return (AE_OK);
 677 }
 678
 679
 680 /*******************************************************************************
 681  *
 682  * FUNCTION:    acpi_ev_gpe_dispatch
 683  *
 684  * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 685  *              gpe_event_info      - Info for this GPE
 686  *              gpe_number          - Number relative to the parent GPE block
 687  *
 688  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 689  *
 690  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 691  *              or method (e.g. _Lxx/_Exx) handler.
 692  *
 693  *              This function executes at interrupt level.
 694  *
 695  ******************************************************************************/
 696
 697 u32
 698 acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
 699                      struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
 700 {
 701         acpi_status status;
 702         u32 return_value;
 703
 704         ACPI_FUNCTION_TRACE(ev_gpe_dispatch);
 705
 706         /*
 707          * Always disable the GPE so that it does not keep firing before
 708          * any asynchronous activity completes (either from the execution
 709          * of a GPE method or an asynchronous GPE handler.)
 710          *
 711          * If there is no handler or method to run, just disable the
 712          * GPE and leave it disabled permanently to prevent further such
 713          * pointless events from firing.
 714          */
 715         status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
 716         if (ACPI_FAILURE(status)) {
 717                 ACPI_EXCEPTION((AE_INFO, status,
 718                                 "Unable to disable GPE %02X", gpe_number));
 719                 return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 720         }
 721
 722         /*
 723          * If edge-triggered, clear the GPE status bit now. Note that
 724          * level-triggered events are cleared after the GPE is serviced.
 725          */
 726         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
 727             ACPI_GPE_EDGE_TRIGGERED) {
 728                 status = acpi_hw_clear_gpe(gpe_event_info);
 729                 if (ACPI_FAILURE(status)) {
 730                         ACPI_EXCEPTION((AE_INFO, status,
 731                                         "Unable to clear GPE %02X",
 732                                         gpe_number));
 733                         (void)acpi_hw_low_set_gpe(gpe_event_info,
 734                                                   ACPI_GPE_CONDITIONAL_ENABLE);
 735                         return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
 736                 }
 737         }
 738
 739         /*
 740          * Dispatch the GPE to either an installed handler or the control
 741          * method associated with this GPE (_Lxx or _Exx). If a handler
 742          * exists, we invoke it and do not attempt to run the method.
 743          * If there is neither a handler nor a method, leave the GPE
 744          * disabled.
 745          */
 746         switch (ACPI_GPE_DISPATCH_TYPE(gpe_event_info->flags)) {
 747         case ACPI_GPE_DISPATCH_HANDLER:
 748
 749                 /* Invoke the installed handler (at interrupt level) */
 750
 751                 return_value =
 752                     gpe_event_info->dispatch.handler->address(gpe_device,
 753                                                               gpe_number,
 754                                                               gpe_event_info->
 755                                                               dispatch.handler->
 756                                                               context);
 757
 758                 /* If requested, clear (if level-triggered) and reenable the GPE */
 759
 760                 if (return_value & ACPI_REENABLE_GPE) {
 761                         (void)acpi_ev_finish_gpe(gpe_event_info);
 762                 }
 763                 break;
 764
 765         case ACPI_GPE_DISPATCH_METHOD:
 766         case ACPI_GPE_DISPATCH_NOTIFY:
 767                 /*
 768                  * Execute the method associated with the GPE
 769                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 770                  */
 771                 status = acpi_os_execute(OSL_GPE_HANDLER,
 772                                          acpi_ev_asynch_execute_gpe_method,
 773                                          gpe_event_info);
 774                 if (ACPI_FAILURE(status)) {
 775                         ACPI_EXCEPTION((AE_INFO, status,
 776                                         "Unable to queue handler for GPE %02X - event disabled",
 777                                         gpe_number));
 778                 }
 779                 break;
 780
 781         default:
 782                 /*
 783                  * No handler or method to run!
 784                  * 03/2010: This case should no longer be possible. We will not allow
 785                  * a GPE to be enabled if it has no handler or method.
 786                  */
 787                 ACPI_ERROR((AE_INFO,
 788                             "No handler or method for GPE %02X, disabling event",
 789                             gpe_number));
 790
 791                 break;
 792         }
 793
 794         return_UINT32(ACPI_INTERRUPT_HANDLED);
 795 }
 796
 797 #endif                          /* !ACPI_REDUCED_HARDWARE */