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