git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/events/evmisc.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evmisc - Miscellaneous event manager support functions
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2008, 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 <acpi/acevents.h>
  46 #include <acpi/acnamesp.h>
  47 #include <acpi/acinterp.h>
  48
  49 #define _COMPONENT          ACPI_EVENTS
  50 ACPI_MODULE_NAME("evmisc")
  51
  52 /* Pointer to FACS needed for the Global Lock */
  53 static struct acpi_table_facs *facs = NULL;
  54
  55 /* Local prototypes */
  56
  57 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context);
  58
  59 static u32 acpi_ev_global_lock_handler(void *context);
  60
  61 static acpi_status acpi_ev_remove_global_lock_handler(void);
  62
  63 /*******************************************************************************
  64  *
  65  * FUNCTION:    acpi_ev_is_notify_object
  66  *
  67  * PARAMETERS:  Node            - Node to check
  68  *
  69  * RETURN:      TRUE if notifies allowed on this object
  70  *
  71  * DESCRIPTION: Check type of node for a object that supports notifies.
  72  *
  73  *              TBD: This could be replaced by a flag bit in the node.
  74  *
  75  ******************************************************************************/
  76
  77 u8 acpi_ev_is_notify_object(struct acpi_namespace_node *node)
  78 {
  79         switch (node->type) {
  80         case ACPI_TYPE_DEVICE:
  81         case ACPI_TYPE_PROCESSOR:
  82         case ACPI_TYPE_THERMAL:
  83                 /*
  84                  * These are the ONLY objects that can receive ACPI notifications
  85                  */
  86                 return (TRUE);
  87
  88         default:
  89                 return (FALSE);
  90         }
  91 }
  92
  93 /*******************************************************************************
  94  *
  95  * FUNCTION:    acpi_ev_queue_notify_request
  96  *
  97  * PARAMETERS:  Node            - NS node for the notified object
  98  *              notify_value    - Value from the Notify() request
  99  *
 100  * RETURN:      Status
 101  *
 102  * DESCRIPTION: Dispatch a device notification event to a previously
 103  *              installed handler.
 104  *
 105  ******************************************************************************/
 106
 107 acpi_status
 108 acpi_ev_queue_notify_request(struct acpi_namespace_node * node,
 109                              u32 notify_value)
 110 {
 111         union acpi_operand_object *obj_desc;
 112         union acpi_operand_object *handler_obj = NULL;
 113         union acpi_generic_state *notify_info;
 114         acpi_status status = AE_OK;
 115
 116         ACPI_FUNCTION_NAME(ev_queue_notify_request);
 117
 118         /*
 119          * For value 3 (Ejection Request), some device method may need to be run.
 120          * For value 2 (Device Wake) if _PRW exists, the _PS0 method may need
 121          *   to be run.
 122          * For value 0x80 (Status Change) on the power button or sleep button,
 123          *   initiate soft-off or sleep operation?
 124          */
 125         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 126                           "Dispatching Notify on [%4.4s] Node %p Value 0x%2.2X (%s)\n",
 127                           acpi_ut_get_node_name(node), node, notify_value,
 128                           acpi_ut_get_notify_name(notify_value)));
 129
 130         /* Get the notify object attached to the NS Node */
 131
 132         obj_desc = acpi_ns_get_attached_object(node);
 133         if (obj_desc) {
 134
 135                 /* We have the notify object, Get the right handler */
 136
 137                 switch (node->type) {
 138
 139                         /* Notify allowed only on these types */
 140
 141                 case ACPI_TYPE_DEVICE:
 142                 case ACPI_TYPE_THERMAL:
 143                 case ACPI_TYPE_PROCESSOR:
 144
 145                         if (notify_value <= ACPI_MAX_SYS_NOTIFY) {
 146                                 handler_obj =
 147                                     obj_desc->common_notify.system_notify;
 148                         } else {
 149                                 handler_obj =
 150                                     obj_desc->common_notify.device_notify;
 151                         }
 152                         break;
 153
 154                 default:
 155                         /* All other types are not supported */
 156                         return (AE_TYPE);
 157                 }
 158         }
 159
 160         /*
 161          * If there is any handler to run, schedule the dispatcher.
 162          * Check for:
 163          * 1) Global system notify handler
 164          * 2) Global device notify handler
 165          * 3) Per-device notify handler
 166          */
 167         if ((acpi_gbl_system_notify.handler
 168              && (notify_value <= ACPI_MAX_SYS_NOTIFY))
 169             || (acpi_gbl_device_notify.handler
 170                 && (notify_value > ACPI_MAX_SYS_NOTIFY)) || handler_obj) {
 171                 notify_info = acpi_ut_create_generic_state();
 172                 if (!notify_info) {
 173                         return (AE_NO_MEMORY);
 174                 }
 175
 176                 if (!handler_obj) {
 177                         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 178                                           "Executing system notify handler for Notify (%4.4s, %X) node %p\n",
 179                                           acpi_ut_get_node_name(node),
 180                                           notify_value, node));
 181                 }
 182
 183                 notify_info->common.descriptor_type =
 184                     ACPI_DESC_TYPE_STATE_NOTIFY;
 185                 notify_info->notify.node = node;
 186                 notify_info->notify.value = (u16) notify_value;
 187                 notify_info->notify.handler_obj = handler_obj;
 188
 189                 status =
 190                     acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_notify_dispatch,
 191                                     notify_info);
 192                 if (ACPI_FAILURE(status)) {
 193                         acpi_ut_delete_generic_state(notify_info);
 194                 }
 195         } else {
 196                 /*
 197                  * There is no notify handler (per-device or system) for this device.
 198                  */
 199                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 200                                   "No notify handler for Notify (%4.4s, %X) node %p\n",
 201                                   acpi_ut_get_node_name(node), notify_value,
 202                                   node));
 203         }
 204
 205         return (status);
 206 }
 207
 208 /*******************************************************************************
 209  *
 210  * FUNCTION:    acpi_ev_notify_dispatch
 211  *
 212  * PARAMETERS:  Context         - To be passed to the notify handler
 213  *
 214  * RETURN:      None.
 215  *
 216  * DESCRIPTION: Dispatch a device notification event to a previously
 217  *              installed handler.
 218  *
 219  ******************************************************************************/
 220
 221 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
 222 {
 223         union acpi_generic_state *notify_info =
 224             (union acpi_generic_state *)context;
 225         acpi_notify_handler global_handler = NULL;
 226         void *global_context = NULL;
 227         union acpi_operand_object *handler_obj;
 228
 229         ACPI_FUNCTION_ENTRY();
 230
 231         /*
 232          * We will invoke a global notify handler if installed.
 233          * This is done _before_ we invoke the per-device handler attached
 234          * to the device.
 235          */
 236         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
 237
 238                 /* Global system notification handler */
 239
 240                 if (acpi_gbl_system_notify.handler) {
 241                         global_handler = acpi_gbl_system_notify.handler;
 242                         global_context = acpi_gbl_system_notify.context;
 243                 }
 244         } else {
 245                 /* Global driver notification handler */
 246
 247                 if (acpi_gbl_device_notify.handler) {
 248                         global_handler = acpi_gbl_device_notify.handler;
 249                         global_context = acpi_gbl_device_notify.context;
 250                 }
 251         }
 252
 253         /* Invoke the system handler first, if present */
 254
 255         if (global_handler) {
 256                 global_handler(notify_info->notify.node,
 257                                notify_info->notify.value, global_context);
 258         }
 259
 260         /* Now invoke the per-device handler, if present */
 261
 262         handler_obj = notify_info->notify.handler_obj;
 263         if (handler_obj) {
 264                 handler_obj->notify.handler(notify_info->notify.node,
 265                                             notify_info->notify.value,
 266                                             handler_obj->notify.context);
 267         }
 268
 269         /* All done with the info object */
 270
 271         acpi_ut_delete_generic_state(notify_info);
 272 }
 273
 274 /*******************************************************************************
 275  *
 276  * FUNCTION:    acpi_ev_global_lock_handler
 277  *
 278  * PARAMETERS:  Context         - From thread interface, not used
 279  *
 280  * RETURN:      ACPI_INTERRUPT_HANDLED
 281  *
 282  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
 283  *              release interrupt occurs. Attempt to acquire the global lock,
 284  *              if successful, signal the thread waiting for the lock.
 285  *
 286  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
 287  * this is not possible for some reason, a separate thread will have to be
 288  * scheduled to do this.
 289  *
 290  ******************************************************************************/
 291
 292 static u32 acpi_ev_global_lock_handler(void *context)
 293 {
 294         u8 acquired = FALSE;
 295
 296         /*
 297          * Attempt to get the lock.
 298          *
 299          * If we don't get it now, it will be marked pending and we will
 300          * take another interrupt when it becomes free.
 301          */
 302         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
 303         if (acquired) {
 304
 305                 /* Got the lock, now wake all threads waiting for it */
 306
 307                 acpi_gbl_global_lock_acquired = TRUE;
 308                 /* Send a unit to the semaphore */
 309
 310                 if (ACPI_FAILURE
 311                     (acpi_os_signal_semaphore
 312                      (acpi_gbl_global_lock_semaphore, 1))) {
 313                         ACPI_ERROR((AE_INFO,
 314                                     "Could not signal Global Lock semaphore"));
 315                 }
 316         }
 317
 318         return (ACPI_INTERRUPT_HANDLED);
 319 }
 320
 321 /*******************************************************************************
 322  *
 323  * FUNCTION:    acpi_ev_init_global_lock_handler
 324  *
 325  * PARAMETERS:  None
 326  *
 327  * RETURN:      Status
 328  *
 329  * DESCRIPTION: Install a handler for the global lock release event
 330  *
 331  ******************************************************************************/
 332
 333 acpi_status acpi_ev_init_global_lock_handler(void)
 334 {
 335         acpi_status status;
 336
 337         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
 338
 339         status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
 340                                          ACPI_CAST_INDIRECT_PTR(struct
 341                                                                 acpi_table_header,
 342                                                                 &facs));
 343         if (ACPI_FAILURE(status)) {
 344                 return_ACPI_STATUS(status);
 345         }
 346
 347         acpi_gbl_global_lock_present = TRUE;
 348         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
 349                                                   acpi_ev_global_lock_handler,
 350                                                   NULL);
 351
 352         /*
 353          * If the global lock does not exist on this platform, the attempt
 354          * to enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick)
 355          * Map to AE_OK, but mark global lock as not present.
 356          * Any attempt to actually use the global lock will be flagged
 357          * with an error.
 358          */
 359         if (status == AE_NO_HARDWARE_RESPONSE) {
 360                 ACPI_ERROR((AE_INFO,
 361                             "No response from Global Lock hardware, disabling lock"));
 362
 363                 acpi_gbl_global_lock_present = FALSE;
 364                 status = AE_OK;
 365         }
 366
 367         return_ACPI_STATUS(status);
 368 }
 369
 370 /*******************************************************************************
 371  *
 372  * FUNCTION:    acpi_ev_remove_global_lock_handler
 373  *
 374  * PARAMETERS:  None
 375  *
 376  * RETURN:      Status
 377  *
 378  * DESCRIPTION: Remove the handler for the Global Lock
 379  *
 380  ******************************************************************************/
 381
 382 static acpi_status acpi_ev_remove_global_lock_handler(void)
 383 {
 384         acpi_status status;
 385
 386         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
 387
 388         acpi_gbl_global_lock_present = FALSE;
 389         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
 390                                                  acpi_ev_global_lock_handler);
 391
 392         return_ACPI_STATUS(status);
 393 }
 394
 395 /******************************************************************************
 396  *
 397  * FUNCTION:    acpi_ev_acquire_global_lock
 398  *
 399  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
 400  *
 401  * RETURN:      Status
 402  *
 403  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
 404  *
 405  * MUTEX:       Interpreter must be locked
 406  *
 407  * Note: The original implementation allowed multiple threads to "acquire" the
 408  * Global Lock, and the OS would hold the lock until the last thread had
 409  * released it. However, this could potentially starve the BIOS out of the
 410  * lock, especially in the case where there is a tight handshake between the
 411  * Embedded Controller driver and the BIOS. Therefore, this implementation
 412  * allows only one thread to acquire the HW Global Lock at a time, and makes
 413  * the global lock appear as a standard mutex on the OS side.
 414  *
 415  *****************************************************************************/
 416 static acpi_thread_id acpi_ev_global_lock_thread_id;
 417 static int acpi_ev_global_lock_acquired;
 418
 419 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
 420 {
 421         acpi_status status = AE_OK;
 422         u8 acquired = FALSE;
 423
 424         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
 425
 426         /*
 427          * Only one thread can acquire the GL at a time, the global_lock_mutex
 428          * enforces this. This interface releases the interpreter if we must wait.
 429          */
 430         status = acpi_ex_system_wait_mutex(
 431                         acpi_gbl_global_lock_mutex->mutex.os_mutex, 0);
 432         if (status == AE_TIME) {
 433                 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
 434                         acpi_ev_global_lock_acquired++;
 435                         return AE_OK;
 436                 }
 437         }
 438
 439         if (ACPI_FAILURE(status)) {
 440                 status = acpi_ex_system_wait_mutex(
 441                                 acpi_gbl_global_lock_mutex->mutex.os_mutex,
 442                                 timeout);
 443         }
 444         if (ACPI_FAILURE(status)) {
 445                 return_ACPI_STATUS(status);
 446         }
 447
 448         acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
 449         acpi_ev_global_lock_acquired++;
 450
 451         /*
 452          * Update the global lock handle and check for wraparound. The handle is
 453          * only used for the external global lock interfaces, but it is updated
 454          * here to properly handle the case where a single thread may acquire the
 455          * lock via both the AML and the acpi_acquire_global_lock interfaces. The
 456          * handle is therefore updated on the first acquire from a given thread
 457          * regardless of where the acquisition request originated.
 458          */
 459         acpi_gbl_global_lock_handle++;
 460         if (acpi_gbl_global_lock_handle == 0) {
 461                 acpi_gbl_global_lock_handle = 1;
 462         }
 463
 464         /*
 465          * Make sure that a global lock actually exists. If not, just treat
 466          * the lock as a standard mutex.
 467          */
 468         if (!acpi_gbl_global_lock_present) {
 469                 acpi_gbl_global_lock_acquired = TRUE;
 470                 return_ACPI_STATUS(AE_OK);
 471         }
 472
 473         /* Attempt to acquire the actual hardware lock */
 474
 475         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
 476         if (acquired) {
 477
 478                 /* We got the lock */
 479
 480                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 481                                   "Acquired hardware Global Lock\n"));
 482
 483                 acpi_gbl_global_lock_acquired = TRUE;
 484                 return_ACPI_STATUS(AE_OK);
 485         }
 486
 487         /*
 488          * Did not get the lock. The pending bit was set above, and we must now
 489          * wait until we get the global lock released interrupt.
 490          */
 491         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n"));
 492
 493         /*
 494          * Wait for handshake with the global lock interrupt handler.
 495          * This interface releases the interpreter if we must wait.
 496          */
 497         status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore,
 498                                                ACPI_WAIT_FOREVER);
 499
 500         return_ACPI_STATUS(status);
 501 }
 502
 503 /*******************************************************************************
 504  *
 505  * FUNCTION:    acpi_ev_release_global_lock
 506  *
 507  * PARAMETERS:  None
 508  *
 509  * RETURN:      Status
 510  *
 511  * DESCRIPTION: Releases ownership of the Global Lock.
 512  *
 513  ******************************************************************************/
 514
 515 acpi_status acpi_ev_release_global_lock(void)
 516 {
 517         u8 pending = FALSE;
 518         acpi_status status = AE_OK;
 519
 520         ACPI_FUNCTION_TRACE(ev_release_global_lock);
 521
 522         /* Lock must be already acquired */
 523
 524         if (!acpi_gbl_global_lock_acquired) {
 525                 ACPI_WARNING((AE_INFO,
 526                               "Cannot release the ACPI Global Lock, it has not been acquired"));
 527                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
 528         }
 529
 530         acpi_ev_global_lock_acquired--;
 531         if (acpi_ev_global_lock_acquired > 0) {
 532                 return AE_OK;
 533         }
 534
 535         if (acpi_gbl_global_lock_present) {
 536
 537                 /* Allow any thread to release the lock */
 538
 539                 ACPI_RELEASE_GLOBAL_LOCK(facs, pending);
 540
 541                 /*
 542                  * If the pending bit was set, we must write GBL_RLS to the control
 543                  * register
 544                  */
 545                 if (pending) {
 546                         status =
 547                             acpi_set_register(ACPI_BITREG_GLOBAL_LOCK_RELEASE,
 548                                               1);
 549                 }
 550
 551                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 552                                   "Released hardware Global Lock\n"));
 553         }
 554
 555         acpi_gbl_global_lock_acquired = FALSE;
 556
 557         /* Release the local GL mutex */
 558         acpi_ev_global_lock_thread_id = NULL;
 559         acpi_ev_global_lock_acquired = 0;
 560         acpi_os_release_mutex(acpi_gbl_global_lock_mutex->mutex.os_mutex);
 561         return_ACPI_STATUS(status);
 562 }
 563
 564 /******************************************************************************
 565  *
 566  * FUNCTION:    acpi_ev_terminate
 567  *
 568  * PARAMETERS:  none
 569  *
 570  * RETURN:      none
 571  *
 572  * DESCRIPTION: Disable events and free memory allocated for table storage.
 573  *
 574  ******************************************************************************/
 575
 576 void acpi_ev_terminate(void)
 577 {
 578         u32 i;
 579         acpi_status status;
 580
 581         ACPI_FUNCTION_TRACE(ev_terminate);
 582
 583         if (acpi_gbl_events_initialized) {
 584                 /*
 585                  * Disable all event-related functionality.
 586                  * In all cases, on error, print a message but obviously we don't abort.
 587                  */
 588
 589                 /* Disable all fixed events */
 590
 591                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
 592                         status = acpi_disable_event(i, 0);
 593                         if (ACPI_FAILURE(status)) {
 594                                 ACPI_ERROR((AE_INFO,
 595                                             "Could not disable fixed event %d",
 596                                             (u32) i));
 597                         }
 598                 }
 599
 600                 /* Disable all GPEs in all GPE blocks */
 601
 602                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block);
 603
 604                 /* Remove SCI handler */
 605
 606                 status = acpi_ev_remove_sci_handler();
 607                 if (ACPI_FAILURE(status)) {
 608                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
 609                 }
 610
 611                 status = acpi_ev_remove_global_lock_handler();
 612                 if (ACPI_FAILURE(status)) {
 613                         ACPI_ERROR((AE_INFO,
 614                                     "Could not remove Global Lock handler"));
 615                 }
 616         }
 617
 618         /* Deallocate all handler objects installed within GPE info structs */
 619
 620         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers);
 621
 622         /* Return to original mode if necessary */
 623
 624         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
 625                 status = acpi_disable();
 626                 if (ACPI_FAILURE(status)) {
 627                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
 628                 }
 629         }
 630         return_VOID;
 631 }