drivers/acpi/events/evmisc.c

   1 /******************************************************************************
   2  *
   3  * Module Name: evmisc - Miscellaneous event manager support functions
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2007, 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 #include <acpi/acinterp.h>
  48
  49 #define _COMPONENT          ACPI_EVENTS
  50 ACPI_MODULE_NAME("evmisc")
  51
  52 /* Names for Notify() values, used for debug output */
  53 #ifdef ACPI_DEBUG_OUTPUT
  54 static const char *acpi_notify_value_names[] = {
  55         "Bus Check",
  56         "Device Check",
  57         "Device Wake",
  58         "Eject Request",
  59         "Device Check Light",
  60         "Frequency Mismatch",
  61         "Bus Mode Mismatch",
  62         "Power Fault"
  63 };
  64 #endif
  65
  66 /* Pointer to FACS needed for the Global Lock */
  67
  68 static struct acpi_table_facs *facs = NULL;
  69
  70 /* Local prototypes */
  71
  72 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context);
  73
  74 static u32 acpi_ev_global_lock_handler(void *context);
  75
  76 static acpi_status acpi_ev_remove_global_lock_handler(void);
  77
  78 /*******************************************************************************
  79  *
  80  * FUNCTION:    acpi_ev_is_notify_object
  81  *
  82  * PARAMETERS:  Node            - Node to check
  83  *
  84  * RETURN:      TRUE if notifies allowed on this object
  85  *
  86  * DESCRIPTION: Check type of node for a object that supports notifies.
  87  *
  88  *              TBD: This could be replaced by a flag bit in the node.
  89  *
  90  ******************************************************************************/
  91
  92 u8 acpi_ev_is_notify_object(struct acpi_namespace_node *node)
  93 {
  94         switch (node->type) {
  95         case ACPI_TYPE_DEVICE:
  96         case ACPI_TYPE_PROCESSOR:
  97         case ACPI_TYPE_POWER:
  98         case ACPI_TYPE_THERMAL:
  99                 /*
 100                  * These are the ONLY objects that can receive ACPI notifications
 101                  */
 102                 return (TRUE);
 103
 104         default:
 105                 return (FALSE);
 106         }
 107 }
 108
 109 /*******************************************************************************
 110  *
 111  * FUNCTION:    acpi_ev_queue_notify_request
 112  *
 113  * PARAMETERS:  Node            - NS node for the notified object
 114  *              notify_value    - Value from the Notify() request
 115  *
 116  * RETURN:      Status
 117  *
 118  * DESCRIPTION: Dispatch a device notification event to a previously
 119  *              installed handler.
 120  *
 121  ******************************************************************************/
 122
 123 acpi_status
 124 acpi_ev_queue_notify_request(struct acpi_namespace_node * node,
 125                              u32 notify_value)
 126 {
 127         union acpi_operand_object *obj_desc;
 128         union acpi_operand_object *handler_obj = NULL;
 129         union acpi_generic_state *notify_info;
 130         acpi_status status = AE_OK;
 131
 132         ACPI_FUNCTION_NAME(ev_queue_notify_request);
 133
 134         /*
 135          * For value 3 (Ejection Request), some device method may need to be run.
 136          * For value 2 (Device Wake) if _PRW exists, the _PS0 method may need
 137          *   to be run.
 138          * For value 0x80 (Status Change) on the power button or sleep button,
 139          *   initiate soft-off or sleep operation?
 140          */
 141         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 142                           "Dispatching Notify(%X) on node %p\n", notify_value,
 143                           node));
 144
 145         if (notify_value <= 7) {
 146                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Notify value: %s\n",
 147                                   acpi_notify_value_names[notify_value]));
 148         } else {
 149                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 150                                   "Notify value: 0x%2.2X **Device Specific**\n",
 151                                   notify_value));
 152         }
 153
 154         /* Get the notify object attached to the NS Node */
 155
 156         obj_desc = acpi_ns_get_attached_object(node);
 157         if (obj_desc) {
 158
 159                 /* We have the notify object, Get the right handler */
 160
 161                 switch (node->type) {
 162                 case ACPI_TYPE_DEVICE:
 163                 case ACPI_TYPE_THERMAL:
 164                 case ACPI_TYPE_PROCESSOR:
 165                 case ACPI_TYPE_POWER:
 166
 167                         if (notify_value <= ACPI_MAX_SYS_NOTIFY) {
 168                                 handler_obj =
 169                                     obj_desc->common_notify.system_notify;
 170                         } else {
 171                                 handler_obj =
 172                                     obj_desc->common_notify.device_notify;
 173                         }
 174                         break;
 175
 176                 default:
 177                         /* All other types are not supported */
 178                         return (AE_TYPE);
 179                 }
 180         }
 181
 182         /* If there is any handler to run, schedule the dispatcher */
 183
 184         if ((acpi_gbl_system_notify.handler
 185              && (notify_value <= ACPI_MAX_SYS_NOTIFY))
 186             || (acpi_gbl_device_notify.handler
 187                 && (notify_value > ACPI_MAX_SYS_NOTIFY)) || handler_obj) {
 188                 notify_info = acpi_ut_create_generic_state();
 189                 if (!notify_info) {
 190                         return (AE_NO_MEMORY);
 191                 }
 192
 193                 notify_info->common.descriptor_type =
 194                     ACPI_DESC_TYPE_STATE_NOTIFY;
 195                 notify_info->notify.node = node;
 196                 notify_info->notify.value = (u16) notify_value;
 197                 notify_info->notify.handler_obj = handler_obj;
 198
 199                 status =
 200                     acpi_os_execute(OSL_NOTIFY_HANDLER, acpi_ev_notify_dispatch,
 201                                     notify_info);
 202                 if (ACPI_FAILURE(status)) {
 203                         acpi_ut_delete_generic_state(notify_info);
 204                 }
 205         }
 206
 207         if (!handler_obj) {
 208                 /*
 209                  * There is no per-device notify handler for this device.
 210                  * This may or may not be a problem.
 211                  */
 212                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 213                                   "No notify handler for Notify(%4.4s, %X) node %p\n",
 214                                   acpi_ut_get_node_name(node), notify_value,
 215                                   node));
 216         }
 217
 218         return (status);
 219 }
 220
 221 /*******************************************************************************
 222  *
 223  * FUNCTION:    acpi_ev_notify_dispatch
 224  *
 225  * PARAMETERS:  Context         - To be passed to the notify handler
 226  *
 227  * RETURN:      None.
 228  *
 229  * DESCRIPTION: Dispatch a device notification event to a previously
 230  *              installed handler.
 231  *
 232  ******************************************************************************/
 233
 234 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
 235 {
 236         union acpi_generic_state *notify_info =
 237             (union acpi_generic_state *)context;
 238         acpi_notify_handler global_handler = NULL;
 239         void *global_context = NULL;
 240         union acpi_operand_object *handler_obj;
 241
 242         ACPI_FUNCTION_ENTRY();
 243
 244         /*
 245          * We will invoke a global notify handler if installed.
 246          * This is done _before_ we invoke the per-device handler attached
 247          * to the device.
 248          */
 249         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
 250
 251                 /* Global system notification handler */
 252
 253                 if (acpi_gbl_system_notify.handler) {
 254                         global_handler = acpi_gbl_system_notify.handler;
 255                         global_context = acpi_gbl_system_notify.context;
 256                 }
 257         } else {
 258                 /* Global driver notification handler */
 259
 260                 if (acpi_gbl_device_notify.handler) {
 261                         global_handler = acpi_gbl_device_notify.handler;
 262                         global_context = acpi_gbl_device_notify.context;
 263                 }
 264         }
 265
 266         /* Invoke the system handler first, if present */
 267
 268         if (global_handler) {
 269                 global_handler(notify_info->notify.node,
 270                                notify_info->notify.value, global_context);
 271         }
 272
 273         /* Now invoke the per-device handler, if present */
 274
 275         handler_obj = notify_info->notify.handler_obj;
 276         if (handler_obj) {
 277                 handler_obj->notify.handler(notify_info->notify.node,
 278                                             notify_info->notify.value,
 279                                             handler_obj->notify.context);
 280         }
 281
 282         /* All done with the info object */
 283
 284         acpi_ut_delete_generic_state(notify_info);
 285 }
 286
 287 /*******************************************************************************
 288  *
 289  * FUNCTION:    acpi_ev_global_lock_handler
 290  *
 291  * PARAMETERS:  Context         - From thread interface, not used
 292  *
 293  * RETURN:      ACPI_INTERRUPT_HANDLED
 294  *
 295  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
 296  *              release interrupt occurs. Attempt to acquire the global lock,
 297  *              if successful, signal the thread waiting for the lock.
 298  *
 299  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
 300  * this is not possible for some reason, a separate thread will have to be
 301  * scheduled to do this.
 302  *
 303  ******************************************************************************/
 304
 305 static u32 acpi_ev_global_lock_handler(void *context)
 306 {
 307         u8 acquired = FALSE;
 308
 309         /*
 310          * Attempt to get the lock.
 311          *
 312          * If we don't get it now, it will be marked pending and we will
 313          * take another interrupt when it becomes free.
 314          */
 315         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
 316         if (acquired) {
 317
 318                 /* Got the lock, now wake all threads waiting for it */
 319
 320                 acpi_gbl_global_lock_acquired = TRUE;
 321                 /* Send a unit to the semaphore */
 322
 323                 if (ACPI_FAILURE(acpi_os_signal_semaphore(
 324                         acpi_gbl_global_lock_semaphore, 1))) {
 325                         ACPI_ERROR((AE_INFO,
 326                                     "Could not signal Global Lock semaphore"));
 327                 }
 328         }
 329
 330         return (ACPI_INTERRUPT_HANDLED);
 331 }
 332
 333 /*******************************************************************************
 334  *
 335  * FUNCTION:    acpi_ev_init_global_lock_handler
 336  *
 337  * PARAMETERS:  None
 338  *
 339  * RETURN:      Status
 340  *
 341  * DESCRIPTION: Install a handler for the global lock release event
 342  *
 343  ******************************************************************************/
 344
 345 acpi_status acpi_ev_init_global_lock_handler(void)
 346 {
 347         acpi_status status;
 348
 349         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
 350
 351         status =
 352             acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
 353                                     (struct acpi_table_header **)&facs);
 354         if (ACPI_FAILURE(status)) {
 355                 return_ACPI_STATUS(status);
 356         }
 357
 358         acpi_gbl_global_lock_present = TRUE;
 359         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
 360                                                   acpi_ev_global_lock_handler,
 361                                                   NULL);
 362
 363         /*
 364          * If the global lock does not exist on this platform, the attempt
 365          * to enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick)
 366          * Map to AE_OK, but mark global lock as not present.
 367          * Any attempt to actually use the global lock will be flagged
 368          * with an error.
 369          */
 370         if (status == AE_NO_HARDWARE_RESPONSE) {
 371                 ACPI_ERROR((AE_INFO,
 372                             "No response from Global Lock hardware, disabling lock"));
 373
 374                 acpi_gbl_global_lock_present = FALSE;
 375                 status = AE_OK;
 376         }
 377
 378         return_ACPI_STATUS(status);
 379 }
 380
 381 /*******************************************************************************
 382  *
 383  * FUNCTION:    acpi_ev_remove_global_lock_handler
 384  *
 385  * PARAMETERS:  None
 386  *
 387  * RETURN:      Status
 388  *
 389  * DESCRIPTION: Remove the handler for the Global Lock
 390  *
 391  ******************************************************************************/
 392
 393 static acpi_status acpi_ev_remove_global_lock_handler(void)
 394 {
 395         acpi_status status;
 396
 397         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
 398
 399         acpi_gbl_global_lock_present = FALSE;
 400         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
 401                                                  acpi_ev_global_lock_handler);
 402
 403         return_ACPI_STATUS(status);
 404 }
 405
 406 /******************************************************************************
 407  *
 408  * FUNCTION:    acpi_ev_acquire_global_lock
 409  *
 410  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
 411  *
 412  * RETURN:      Status
 413  *
 414  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
 415  *
 416  * MUTEX:       Interpreter must be locked
 417  *
 418  * Note: The original implementation allowed multiple threads to "acquire" the
 419  * Global Lock, and the OS would hold the lock until the last thread had
 420  * released it. However, this could potentially starve the BIOS out of the
 421  * lock, especially in the case where there is a tight handshake between the
 422  * Embedded Controller driver and the BIOS. Therefore, this implementation
 423  * allows only one thread to acquire the HW Global Lock at a time, and makes
 424  * the global lock appear as a standard mutex on the OS side.
 425  *
 426  *****************************************************************************/
 427 static acpi_thread_id acpi_ev_global_lock_thread_id;
 428 static int acpi_ev_global_lock_acquired;
 429
 430 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
 431 {
 432         acpi_status status = AE_OK;
 433         u8 acquired = FALSE;
 434
 435         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
 436
 437         /*
 438          * Only one thread can acquire the GL at a time, the global_lock_mutex
 439          * enforces this. This interface releases the interpreter if we must wait.
 440          */
 441         status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, 0);
 442         if (status == AE_TIME) {
 443                 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
 444                         acpi_ev_global_lock_acquired++;
 445                         return AE_OK;
 446                 }
 447         }
 448
 449         if (ACPI_FAILURE(status)) {
 450                 status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, timeout);
 451         }
 452         if (ACPI_FAILURE(status)) {
 453                 return_ACPI_STATUS(status);
 454         }
 455
 456         acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
 457         acpi_ev_global_lock_acquired++;
 458
 459         /*
 460          * Make sure that a global lock actually exists. If not, just treat
 461          * the lock as a standard mutex.
 462          */
 463         if (!acpi_gbl_global_lock_present) {
 464                 acpi_gbl_global_lock_acquired = TRUE;
 465                 return_ACPI_STATUS(AE_OK);
 466         }
 467
 468         /* Attempt to acquire the actual hardware lock */
 469
 470         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
 471         if (acquired) {
 472
 473                 /* We got the lock */
 474
 475                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 476                                   "Acquired hardware Global Lock\n"));
 477
 478                 acpi_gbl_global_lock_acquired = TRUE;
 479                 return_ACPI_STATUS(AE_OK);
 480         }
 481
 482         /*
 483          * Did not get the lock. The pending bit was set above, and we must now
 484          * wait until we get the global lock released interrupt.
 485          */
 486         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n"));
 487
 488         /*
 489          * Wait for handshake with the global lock interrupt handler.
 490          * This interface releases the interpreter if we must wait.
 491          */
 492         status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore,
 493                                                ACPI_WAIT_FOREVER);
 494
 495         return_ACPI_STATUS(status);
 496 }
 497
 498 /*******************************************************************************
 499  *
 500  * FUNCTION:    acpi_ev_release_global_lock
 501  *
 502  * PARAMETERS:  None
 503  *
 504  * RETURN:      Status
 505  *
 506  * DESCRIPTION: Releases ownership of the Global Lock.
 507  *
 508  ******************************************************************************/
 509
 510 acpi_status acpi_ev_release_global_lock(void)
 511 {
 512         u8 pending = FALSE;
 513         acpi_status status = AE_OK;
 514
 515         ACPI_FUNCTION_TRACE(ev_release_global_lock);
 516
 517         /* Lock must be already acquired */
 518
 519         if (!acpi_gbl_global_lock_acquired) {
 520                 ACPI_WARNING((AE_INFO,
 521                               "Cannot release the ACPI Global Lock, it has not been acquired"));
 522                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
 523         }
 524
 525         acpi_ev_global_lock_acquired--;
 526         if (acpi_ev_global_lock_acquired > 0) {
 527                 return AE_OK;
 528         }
 529
 530         if (acpi_gbl_global_lock_present) {
 531
 532                 /* Allow any thread to release the lock */
 533
 534                 ACPI_RELEASE_GLOBAL_LOCK(facs, pending);
 535
 536                 /*
 537                  * If the pending bit was set, we must write GBL_RLS to the control
 538                  * register
 539                  */
 540                 if (pending) {
 541                         status =
 542                             acpi_set_register(ACPI_BITREG_GLOBAL_LOCK_RELEASE,
 543                                               1);
 544                 }
 545
 546                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 547                                   "Released hardware Global Lock\n"));
 548         }
 549
 550         acpi_gbl_global_lock_acquired = FALSE;
 551
 552         /* Release the local GL mutex */
 553         acpi_ev_global_lock_thread_id = NULL;
 554         acpi_ev_global_lock_acquired = 0;
 555         acpi_os_release_mutex(acpi_gbl_global_lock_mutex);
 556         return_ACPI_STATUS(status);
 557 }
 558
 559 /******************************************************************************
 560  *
 561  * FUNCTION:    acpi_ev_terminate
 562  *
 563  * PARAMETERS:  none
 564  *
 565  * RETURN:      none
 566  *
 567  * DESCRIPTION: Disable events and free memory allocated for table storage.
 568  *
 569  ******************************************************************************/
 570
 571 void acpi_ev_terminate(void)
 572 {
 573         acpi_native_uint i;
 574         acpi_status status;
 575
 576         ACPI_FUNCTION_TRACE(ev_terminate);
 577
 578         if (acpi_gbl_events_initialized) {
 579                 /*
 580                  * Disable all event-related functionality.
 581                  * In all cases, on error, print a message but obviously we don't abort.
 582                  */
 583
 584                 /* Disable all fixed events */
 585
 586                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
 587                         status = acpi_disable_event((u32) i, 0);
 588                         if (ACPI_FAILURE(status)) {
 589                                 ACPI_ERROR((AE_INFO,
 590                                             "Could not disable fixed event %d",
 591                                             (u32) i));
 592                         }
 593                 }
 594
 595                 /* Disable all GPEs in all GPE blocks */
 596
 597                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block);
 598
 599                 /* Remove SCI handler */
 600
 601                 status = acpi_ev_remove_sci_handler();
 602                 if (ACPI_FAILURE(status)) {
 603                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
 604                 }
 605
 606                 status = acpi_ev_remove_global_lock_handler();
 607                 if (ACPI_FAILURE(status)) {
 608                         ACPI_ERROR((AE_INFO,
 609                                     "Could not remove Global Lock handler"));
 610                 }
 611         }
 612
 613         /* Deallocate all handler objects installed within GPE info structs */
 614
 615         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers);
 616
 617         /* Return to original mode if necessary */
 618
 619         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
 620                 status = acpi_disable();
 621                 if (ACPI_FAILURE(status)) {
 622                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
 623                 }
 624         }
 625         return_VOID;
 626 }