drivers/acpi/events/evgpe.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evgpe - General Purpose Event handling and dispatch
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2004, R. Byron Moore
   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 <acpi/acevents.h>
  46 #include <acpi/acnamesp.h>
  47
  48 #define _COMPONENT          ACPI_EVENTS
  49          ACPI_MODULE_NAME    ("evgpe")
  50
  51
  52 /*******************************************************************************
  53  *
  54  * FUNCTION:    acpi_ev_get_gpe_event_info
  55  *
  56  * PARAMETERS:  gpe_device          - Device node.  NULL for GPE0/GPE1
  57  *              gpe_number          - Raw GPE number
  58  *
  59  * RETURN:      A GPE event_info struct. NULL if not a valid GPE
  60  *
  61  * DESCRIPTION: Returns the event_info struct associated with this GPE.
  62  *              Validates the gpe_block and the gpe_number
  63  *
  64  *              Should be called only when the GPE lists are semaphore locked
  65  *              and not subject to change.
  66  *
  67  ******************************************************************************/
  68
  69 struct acpi_gpe_event_info *
  70 acpi_ev_get_gpe_event_info (
  71         acpi_handle                     gpe_device,
  72         u32                             gpe_number)
  73 {
  74         union acpi_operand_object       *obj_desc;
  75         struct acpi_gpe_block_info      *gpe_block;
  76         acpi_native_uint                i;
  77
  78
  79         ACPI_FUNCTION_ENTRY ();
  80
  81
  82         /* A NULL gpe_block means use the FADT-defined GPE block(s) */
  83
  84         if (!gpe_device) {
  85                 /* Examine GPE Block 0 and 1 (These blocks are permanent) */
  86
  87                 for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
  88                         gpe_block = acpi_gbl_gpe_fadt_blocks[i];
  89                         if (gpe_block) {
  90                                 if ((gpe_number >= gpe_block->block_base_number) &&
  91                                         (gpe_number < gpe_block->block_base_number + (gpe_block->register_count * 8))) {
  92                                         return (&gpe_block->event_info[gpe_number - gpe_block->block_base_number]);
  93                                 }
  94                         }
  95                 }
  96
  97                 /* The gpe_number was not in the range of either FADT GPE block */
  98
  99                 return (NULL);
 100         }
 101
 102         /* A Non-NULL gpe_device means this is a GPE Block Device */
 103
 104         obj_desc = acpi_ns_get_attached_object ((struct acpi_namespace_node *) gpe_device);
 105         if (!obj_desc ||
 106                 !obj_desc->device.gpe_block) {
 107                 return (NULL);
 108         }
 109
 110         gpe_block = obj_desc->device.gpe_block;
 111
 112         if ((gpe_number >= gpe_block->block_base_number) &&
 113                 (gpe_number < gpe_block->block_base_number + (gpe_block->register_count * 8))) {
 114                 return (&gpe_block->event_info[gpe_number - gpe_block->block_base_number]);
 115         }
 116
 117         return (NULL);
 118 }
 119
 120
 121 /*******************************************************************************
 122  *
 123  * FUNCTION:    acpi_ev_gpe_detect
 124  *
 125  * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 126  *                                    Can have multiple GPE blocks attached.
 127  *
 128  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 129  *
 130  * DESCRIPTION: Detect if any GP events have occurred.  This function is
 131  *              executed at interrupt level.
 132  *
 133  ******************************************************************************/
 134
 135 u32
 136 acpi_ev_gpe_detect (
 137         struct acpi_gpe_xrupt_info      *gpe_xrupt_list)
 138 {
 139         u32                             int_status = ACPI_INTERRUPT_NOT_HANDLED;
 140         u8                              enabled_status_byte;
 141         struct acpi_gpe_register_info   *gpe_register_info;
 142         u32                             in_value;
 143         acpi_status                     status;
 144         struct acpi_gpe_block_info      *gpe_block;
 145         u32                             i;
 146         u32                             j;
 147
 148
 149         ACPI_FUNCTION_NAME ("ev_gpe_detect");
 150
 151         /* Check for the case where there are no GPEs */
 152
 153         if (!gpe_xrupt_list) {
 154                 return (int_status);
 155         }
 156
 157         /* Examine all GPE blocks attached to this interrupt level */
 158
 159         acpi_os_acquire_lock (acpi_gbl_gpe_lock, ACPI_ISR);
 160         gpe_block = gpe_xrupt_list->gpe_block_list_head;
 161         while (gpe_block) {
 162                 /*
 163                  * Read all of the 8-bit GPE status and enable registers
 164                  * in this GPE block, saving all of them.
 165                  * Find all currently active GP events.
 166                  */
 167                 for (i = 0; i < gpe_block->register_count; i++) {
 168                         /* Get the next status/enable pair */
 169
 170                         gpe_register_info = &gpe_block->register_info[i];
 171
 172                         /* Read the Status Register */
 173
 174                         status = acpi_hw_low_level_read (ACPI_GPE_REGISTER_WIDTH, &in_value,
 175                                          &gpe_register_info->status_address);
 176                         gpe_register_info->status = (u8) in_value;
 177                         if (ACPI_FAILURE (status)) {
 178                                 goto unlock_and_exit;
 179                         }
 180
 181                         /* Read the Enable Register */
 182
 183                         status = acpi_hw_low_level_read (ACPI_GPE_REGISTER_WIDTH, &in_value,
 184                                          &gpe_register_info->enable_address);
 185                         gpe_register_info->enable = (u8) in_value;
 186                         if (ACPI_FAILURE (status)) {
 187                                 goto unlock_and_exit;
 188                         }
 189
 190                         ACPI_DEBUG_PRINT ((ACPI_DB_INTERRUPTS,
 191                                 "GPE pair: Status %8.8X%8.8X = %02X, Enable %8.8X%8.8X = %02X\n",
 192                                 ACPI_FORMAT_UINT64 (gpe_register_info->status_address.address),
 193                                 gpe_register_info->status,
 194                                 ACPI_FORMAT_UINT64 (gpe_register_info->enable_address.address),
 195                                 gpe_register_info->enable));
 196
 197                         /* First check if there is anything active at all in this register */
 198
 199                         enabled_status_byte = (u8) (gpe_register_info->status &
 200                                            gpe_register_info->enable);
 201                         if (!enabled_status_byte) {
 202                                 /* No active GPEs in this register, move on */
 203
 204                                 continue;
 205                         }
 206
 207                         /* Now look at the individual GPEs in this byte register */
 208
 209                         for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {
 210                                 /* Examine one GPE bit */
 211
 212                                 if (enabled_status_byte & acpi_gbl_decode_to8bit[j]) {
 213                                         /*
 214                                          * Found an active GPE. Dispatch the event to a handler
 215                                          * or method.
 216                                          */
 217                                         int_status |= acpi_ev_gpe_dispatch (
 218                                                           &gpe_block->event_info[(i * ACPI_GPE_REGISTER_WIDTH) + j],
 219                                                           j + gpe_register_info->base_gpe_number);
 220                                 }
 221                         }
 222                 }
 223
 224                 gpe_block = gpe_block->next;
 225         }
 226
 227 unlock_and_exit:
 228
 229         acpi_os_release_lock (acpi_gbl_gpe_lock, ACPI_ISR);
 230         return (int_status);
 231 }
 232
 233
 234 /*******************************************************************************
 235  *
 236  * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 237  *
 238  * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 239  *
 240  * RETURN:      None
 241  *
 242  * DESCRIPTION: Perform the actual execution of a GPE control method.  This
 243  *              function is called from an invocation of acpi_os_queue_for_execution
 244  *              (and therefore does NOT execute at interrupt level) so that
 245  *              the control method itself is not executed in the context of
 246  *              an interrupt handler.
 247  *
 248  ******************************************************************************/
 249
 250 static void ACPI_SYSTEM_XFACE
 251 acpi_ev_asynch_execute_gpe_method (
 252         void                            *context)
 253 {
 254         struct acpi_gpe_event_info      *gpe_event_info = (void *) context;
 255         u32                             gpe_number = 0;
 256         acpi_status                     status;
 257         struct acpi_gpe_event_info      local_gpe_event_info;
 258
 259
 260         ACPI_FUNCTION_TRACE ("ev_asynch_execute_gpe_method");
 261
 262
 263         status = acpi_ut_acquire_mutex (ACPI_MTX_EVENTS);
 264         if (ACPI_FAILURE (status)) {
 265                 return_VOID;
 266         }
 267
 268         /* Must revalidate the gpe_number/gpe_block */
 269
 270         if (!acpi_ev_valid_gpe_event (gpe_event_info)) {
 271                 status = acpi_ut_release_mutex (ACPI_MTX_EVENTS);
 272                 return_VOID;
 273         }
 274
 275         /*
 276          * Take a snapshot of the GPE info for this level - we copy the
 277          * info to prevent a race condition with remove_handler/remove_block.
 278          */
 279         ACPI_MEMCPY (&local_gpe_event_info, gpe_event_info, sizeof (struct acpi_gpe_event_info));
 280
 281         status = acpi_ut_release_mutex (ACPI_MTX_EVENTS);
 282         if (ACPI_FAILURE (status)) {
 283                 return_VOID;
 284         }
 285
 286         if (local_gpe_event_info.method_node) {
 287                 /*
 288                  * Invoke the GPE Method (_Lxx, _Exx):
 289                  * (Evaluate the _Lxx/_Exx control method that corresponds to this GPE.)
 290                  */
 291                 status = acpi_ns_evaluate_by_handle (local_gpe_event_info.method_node, NULL, NULL);
 292                 if (ACPI_FAILURE (status)) {
 293                         ACPI_REPORT_ERROR (("%s while evaluating method [%4.4s] for GPE[%2X]\n",
 294                                 acpi_format_exception (status),
 295                                 acpi_ut_get_node_name (local_gpe_event_info.method_node), gpe_number));
 296                 }
 297         }
 298
 299         if ((local_gpe_event_info.flags & ACPI_GPE_XRUPT_TYPE_MASK) == ACPI_GPE_LEVEL_TRIGGERED) {
 300                 /*
 301                  * GPE is level-triggered, we clear the GPE status bit after handling
 302                  * the event.
 303                  */
 304                 status = acpi_hw_clear_gpe (&local_gpe_event_info);
 305                 if (ACPI_FAILURE (status)) {
 306                         return_VOID;
 307                 }
 308         }
 309
 310         /* Enable this GPE */
 311
 312         (void) acpi_hw_enable_gpe (&local_gpe_event_info);
 313         return_VOID;
 314 }
 315
 316
 317 /*******************************************************************************
 318  *
 319  * FUNCTION:    acpi_ev_gpe_dispatch
 320  *
 321  * PARAMETERS:  gpe_event_info  - info for this GPE
 322  *              gpe_number      - Number relative to the parent GPE block
 323  *
 324  * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 325  *
 326  * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 327  *              or method (e.g. _Lxx/_Exx) handler.
 328  *
 329  *              This function executes at interrupt level.
 330  *
 331  ******************************************************************************/
 332
 333 u32
 334 acpi_ev_gpe_dispatch (
 335         struct acpi_gpe_event_info      *gpe_event_info,
 336         u32                             gpe_number)
 337 {
 338         acpi_status                     status;
 339
 340
 341         ACPI_FUNCTION_TRACE ("ev_gpe_dispatch");
 342
 343
 344         /*
 345          * If edge-triggered, clear the GPE status bit now.  Note that
 346          * level-triggered events are cleared after the GPE is serviced.
 347          */
 348         if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) == ACPI_GPE_EDGE_TRIGGERED) {
 349                 status = acpi_hw_clear_gpe (gpe_event_info);
 350                 if (ACPI_FAILURE (status)) {
 351                         ACPI_REPORT_ERROR (("acpi_ev_gpe_dispatch: Unable to clear GPE[%2X]\n",
 352                                 gpe_number));
 353                         return_VALUE (ACPI_INTERRUPT_NOT_HANDLED);
 354                 }
 355         }
 356
 357         /*
 358          * Dispatch the GPE to either an installed handler, or the control
 359          * method associated with this GPE (_Lxx or _Exx).
 360          * If a handler exists, we invoke it and do not attempt to run the method.
 361          * If there is neither a handler nor a method, we disable the level to
 362          * prevent further events from coming in here.
 363          */
 364         if (gpe_event_info->handler) {
 365                 /* Invoke the installed handler (at interrupt level) */
 366
 367                 gpe_event_info->handler (gpe_event_info->context);
 368
 369                 /* It is now safe to clear level-triggered events. */
 370
 371                 if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) == ACPI_GPE_LEVEL_TRIGGERED) {
 372                         status = acpi_hw_clear_gpe (gpe_event_info);
 373                         if (ACPI_FAILURE (status)) {
 374                                 ACPI_REPORT_ERROR ((
 375                                         "acpi_ev_gpe_dispatch: Unable to clear GPE[%2X]\n",
 376                                         gpe_number));
 377                                 return_VALUE (ACPI_INTERRUPT_NOT_HANDLED);
 378                         }
 379                 }
 380         }
 381         else if (gpe_event_info->method_node) {
 382                 /*
 383                  * Disable GPE, so it doesn't keep firing before the method has a
 384                  * chance to run.
 385                  */
 386                 status = acpi_hw_disable_gpe (gpe_event_info);
 387                 if (ACPI_FAILURE (status)) {
 388                         ACPI_REPORT_ERROR ((
 389                                 "acpi_ev_gpe_dispatch: Unable to disable GPE[%2X]\n",
 390                                 gpe_number));
 391                         return_VALUE (ACPI_INTERRUPT_NOT_HANDLED);
 392                 }
 393
 394                 /*
 395                  * Execute the method associated with the GPE
 396                  * NOTE: Level-triggered GPEs are cleared after the method completes.
 397                  */
 398                 if (ACPI_FAILURE (acpi_os_queue_for_execution (OSD_PRIORITY_GPE,
 399                                  acpi_ev_asynch_execute_gpe_method,
 400                                  gpe_event_info))) {
 401                         ACPI_REPORT_ERROR ((
 402                                 "acpi_ev_gpe_dispatch: Unable to queue handler for GPE[%2X], event is disabled\n",
 403                                 gpe_number));
 404                 }
 405         }
 406         else {
 407                 /* No handler or method to run! */
 408
 409                 ACPI_REPORT_ERROR ((
 410                         "acpi_ev_gpe_dispatch: No handler or method for GPE[%2X], disabling event\n",
 411                         gpe_number));
 412
 413                 /*
 414                  * Disable the GPE.  The GPE will remain disabled until the ACPI
 415                  * Core Subsystem is restarted, or a handler is installed.
 416                  */
 417                 status = acpi_hw_disable_gpe (gpe_event_info);
 418                 if (ACPI_FAILURE (status)) {
 419                         ACPI_REPORT_ERROR ((
 420                                 "acpi_ev_gpe_dispatch: Unable to disable GPE[%2X]\n",
 421                                 gpe_number));
 422                         return_VALUE (ACPI_INTERRUPT_NOT_HANDLED);
 423                 }
 424         }
 425
 426         return_VALUE (ACPI_INTERRUPT_HANDLED);
 427 }
 428