drivers/acpi/acpica/evgpe.c

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