drivers/acpi/acpica/evgpe.c

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