err.no 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 - 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                 acpi_ex_relinquish_interpreter();
 200
 201                 acpi_ev_notify_dispatch(notify_info);
 202
 203                 acpi_ex_reacquire_interpreter();
 204         }
 205
 206         if (!handler_obj) {
 207                 /*
 208                  * There is no per-device notify handler for this device.
 209                  * This may or may not be a problem.
 210                  */
 211                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 212                                   "No notify handler for Notify(%4.4s, %X) node %p\n",
 213                                   acpi_ut_get_node_name(node), notify_value,
 214                                   node));
 215         }
 216
 217         return (status);
 218 }
 219
 220 /*******************************************************************************
 221  *
 222  * FUNCTION:    acpi_ev_notify_dispatch
 223  *
 224  * PARAMETERS:  Context         - To be passed to the notify handler
 225  *
 226  * RETURN:      None.
 227  *
 228  * DESCRIPTION: Dispatch a device notification event to a previously
 229  *              installed handler.
 230  *
 231  ******************************************************************************/
 232
 233 static void ACPI_SYSTEM_XFACE acpi_ev_notify_dispatch(void *context)
 234 {
 235         union acpi_generic_state *notify_info =
 236             (union acpi_generic_state *)context;
 237         acpi_notify_handler global_handler = NULL;
 238         void *global_context = NULL;
 239         union acpi_operand_object *handler_obj;
 240
 241         ACPI_FUNCTION_ENTRY();
 242
 243         /*
 244          * We will invoke a global notify handler if installed.
 245          * This is done _before_ we invoke the per-device handler attached
 246          * to the device.
 247          */
 248         if (notify_info->notify.value <= ACPI_MAX_SYS_NOTIFY) {
 249
 250                 /* Global system notification handler */
 251
 252                 if (acpi_gbl_system_notify.handler) {
 253                         global_handler = acpi_gbl_system_notify.handler;
 254                         global_context = acpi_gbl_system_notify.context;
 255                 }
 256         } else {
 257                 /* Global driver notification handler */
 258
 259                 if (acpi_gbl_device_notify.handler) {
 260                         global_handler = acpi_gbl_device_notify.handler;
 261                         global_context = acpi_gbl_device_notify.context;
 262                 }
 263         }
 264
 265         /* Invoke the system handler first, if present */
 266
 267         if (global_handler) {
 268                 global_handler(notify_info->notify.node,
 269                                notify_info->notify.value, global_context);
 270         }
 271
 272         /* Now invoke the per-device handler, if present */
 273
 274         handler_obj = notify_info->notify.handler_obj;
 275         if (handler_obj) {
 276                 handler_obj->notify.handler(notify_info->notify.node,
 277                                             notify_info->notify.value,
 278                                             handler_obj->notify.context);
 279         }
 280
 281         /* All done with the info object */
 282
 283         acpi_ut_delete_generic_state(notify_info);
 284 }
 285
 286 /*******************************************************************************
 287  *
 288  * FUNCTION:    acpi_ev_global_lock_handler
 289  *
 290  * PARAMETERS:  Context         - From thread interface, not used
 291  *
 292  * RETURN:      ACPI_INTERRUPT_HANDLED
 293  *
 294  * DESCRIPTION: Invoked directly from the SCI handler when a global lock
 295  *              release interrupt occurs. Attempt to acquire the global lock,
 296  *              if successful, signal the thread waiting for the lock.
 297  *
 298  * NOTE: Assumes that the semaphore can be signaled from interrupt level. If
 299  * this is not possible for some reason, a separate thread will have to be
 300  * scheduled to do this.
 301  *
 302  ******************************************************************************/
 303
 304 static u32 acpi_ev_global_lock_handler(void *context)
 305 {
 306         u8 acquired = FALSE;
 307
 308         /*
 309          * Attempt to get the lock.
 310          *
 311          * If we don't get it now, it will be marked pending and we will
 312          * take another interrupt when it becomes free.
 313          */
 314         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
 315         if (acquired) {
 316
 317                 /* Got the lock, now wake all threads waiting for it */
 318
 319                 acpi_gbl_global_lock_acquired = TRUE;
 320                 /* Send a unit to the semaphore */
 321
 322                 if (ACPI_FAILURE(acpi_os_signal_semaphore(
 323                         acpi_gbl_global_lock_semaphore, 1))) {
 324                         ACPI_ERROR((AE_INFO,
 325                                     "Could not signal Global Lock semaphore"));
 326                 }
 327         }
 328
 329         return (ACPI_INTERRUPT_HANDLED);
 330 }
 331
 332 /*******************************************************************************
 333  *
 334  * FUNCTION:    acpi_ev_init_global_lock_handler
 335  *
 336  * PARAMETERS:  None
 337  *
 338  * RETURN:      Status
 339  *
 340  * DESCRIPTION: Install a handler for the global lock release event
 341  *
 342  ******************************************************************************/
 343
 344 acpi_status acpi_ev_init_global_lock_handler(void)
 345 {
 346         acpi_status status;
 347
 348         ACPI_FUNCTION_TRACE(ev_init_global_lock_handler);
 349
 350         status =
 351             acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
 352                                     (struct acpi_table_header **)&facs);
 353         if (ACPI_FAILURE(status)) {
 354                 return_ACPI_STATUS(status);
 355         }
 356
 357         acpi_gbl_global_lock_present = TRUE;
 358         status = acpi_install_fixed_event_handler(ACPI_EVENT_GLOBAL,
 359                                                   acpi_ev_global_lock_handler,
 360                                                   NULL);
 361
 362         /*
 363          * If the global lock does not exist on this platform, the attempt
 364          * to enable GBL_STATUS will fail (the GBL_ENABLE bit will not stick)
 365          * Map to AE_OK, but mark global lock as not present.
 366          * Any attempt to actually use the global lock will be flagged
 367          * with an error.
 368          */
 369         if (status == AE_NO_HARDWARE_RESPONSE) {
 370                 ACPI_ERROR((AE_INFO,
 371                             "No response from Global Lock hardware, disabling lock"));
 372
 373                 acpi_gbl_global_lock_present = FALSE;
 374                 status = AE_OK;
 375         }
 376
 377         return_ACPI_STATUS(status);
 378 }
 379
 380 /*******************************************************************************
 381  *
 382  * FUNCTION:    acpi_ev_remove_global_lock_handler
 383  *
 384  * PARAMETERS:  None
 385  *
 386  * RETURN:      Status
 387  *
 388  * DESCRIPTION: Remove the handler for the Global Lock
 389  *
 390  ******************************************************************************/
 391
 392 static acpi_status acpi_ev_remove_global_lock_handler(void)
 393 {
 394         acpi_status status;
 395
 396         ACPI_FUNCTION_TRACE(ev_remove_global_lock_handler);
 397
 398         acpi_gbl_global_lock_present = FALSE;
 399         status = acpi_remove_fixed_event_handler(ACPI_EVENT_GLOBAL,
 400                                                  acpi_ev_global_lock_handler);
 401
 402         return_ACPI_STATUS(status);
 403 }
 404
 405 /******************************************************************************
 406  *
 407  * FUNCTION:    acpi_ev_acquire_global_lock
 408  *
 409  * PARAMETERS:  Timeout         - Max time to wait for the lock, in millisec.
 410  *
 411  * RETURN:      Status
 412  *
 413  * DESCRIPTION: Attempt to gain ownership of the Global Lock.
 414  *
 415  * MUTEX:       Interpreter must be locked
 416  *
 417  * Note: The original implementation allowed multiple threads to "acquire" the
 418  * Global Lock, and the OS would hold the lock until the last thread had
 419  * released it. However, this could potentially starve the BIOS out of the
 420  * lock, especially in the case where there is a tight handshake between the
 421  * Embedded Controller driver and the BIOS. Therefore, this implementation
 422  * allows only one thread to acquire the HW Global Lock at a time, and makes
 423  * the global lock appear as a standard mutex on the OS side.
 424  *
 425  *****************************************************************************/
 426 static acpi_thread_id acpi_ev_global_lock_thread_id;
 427 static int acpi_ev_global_lock_acquired;
 428
 429 acpi_status acpi_ev_acquire_global_lock(u16 timeout)
 430 {
 431         acpi_status status = AE_OK;
 432         u8 acquired = FALSE;
 433
 434         ACPI_FUNCTION_TRACE(ev_acquire_global_lock);
 435
 436         /*
 437          * Only one thread can acquire the GL at a time, the global_lock_mutex
 438          * enforces this. This interface releases the interpreter if we must wait.
 439          */
 440         status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, 0);
 441         if (status == AE_TIME) {
 442                 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
 443                         acpi_ev_global_lock_acquired++;
 444                         return AE_OK;
 445                 }
 446         }
 447
 448         if (ACPI_FAILURE(status)) {
 449                 status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, timeout);
 450         }
 451         if (ACPI_FAILURE(status)) {
 452                 return_ACPI_STATUS(status);
 453         }
 454
 455         acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
 456         acpi_ev_global_lock_acquired++;
 457
 458         /*
 459          * Make sure that a global lock actually exists. If not, just treat
 460          * the lock as a standard mutex.
 461          */
 462         if (!acpi_gbl_global_lock_present) {
 463                 acpi_gbl_global_lock_acquired = TRUE;
 464                 return_ACPI_STATUS(AE_OK);
 465         }
 466
 467         /* Attempt to acquire the actual hardware lock */
 468
 469         ACPI_ACQUIRE_GLOBAL_LOCK(facs, acquired);
 470         if (acquired) {
 471
 472                 /* We got the lock */
 473
 474                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 475                                   "Acquired hardware Global Lock\n"));
 476
 477                 acpi_gbl_global_lock_acquired = TRUE;
 478                 return_ACPI_STATUS(AE_OK);
 479         }
 480
 481         /*
 482          * Did not get the lock. The pending bit was set above, and we must now
 483          * wait until we get the global lock released interrupt.
 484          */
 485         ACPI_DEBUG_PRINT((ACPI_DB_EXEC, "Waiting for hardware Global Lock\n"));
 486
 487         /*
 488          * Wait for handshake with the global lock interrupt handler.
 489          * This interface releases the interpreter if we must wait.
 490          */
 491         status = acpi_ex_system_wait_semaphore(acpi_gbl_global_lock_semaphore,
 492                                                ACPI_WAIT_FOREVER);
 493
 494         return_ACPI_STATUS(status);
 495 }
 496
 497 /*******************************************************************************
 498  *
 499  * FUNCTION:    acpi_ev_release_global_lock
 500  *
 501  * PARAMETERS:  None
 502  *
 503  * RETURN:      Status
 504  *
 505  * DESCRIPTION: Releases ownership of the Global Lock.
 506  *
 507  ******************************************************************************/
 508
 509 acpi_status acpi_ev_release_global_lock(void)
 510 {
 511         u8 pending = FALSE;
 512         acpi_status status = AE_OK;
 513
 514         ACPI_FUNCTION_TRACE(ev_release_global_lock);
 515
 516         /* Lock must be already acquired */
 517
 518         if (!acpi_gbl_global_lock_acquired) {
 519                 ACPI_WARNING((AE_INFO,
 520                               "Cannot release the ACPI Global Lock, it has not been acquired"));
 521                 return_ACPI_STATUS(AE_NOT_ACQUIRED);
 522         }
 523
 524         acpi_ev_global_lock_acquired--;
 525         if (acpi_ev_global_lock_acquired > 0) {
 526                 return AE_OK;
 527         }
 528
 529         if (acpi_gbl_global_lock_present) {
 530
 531                 /* Allow any thread to release the lock */
 532
 533                 ACPI_RELEASE_GLOBAL_LOCK(facs, pending);
 534
 535                 /*
 536                  * If the pending bit was set, we must write GBL_RLS to the control
 537                  * register
 538                  */
 539                 if (pending) {
 540                         status =
 541                             acpi_set_register(ACPI_BITREG_GLOBAL_LOCK_RELEASE,
 542                                               1);
 543                 }
 544
 545                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 546                                   "Released hardware Global Lock\n"));
 547         }
 548
 549         acpi_gbl_global_lock_acquired = FALSE;
 550
 551         /* Release the local GL mutex */
 552         acpi_ev_global_lock_thread_id = NULL;
 553         acpi_ev_global_lock_acquired = 0;
 554         acpi_os_release_mutex(acpi_gbl_global_lock_mutex);
 555         return_ACPI_STATUS(status);
 556 }
 557
 558 /******************************************************************************
 559  *
 560  * FUNCTION:    acpi_ev_terminate
 561  *
 562  * PARAMETERS:  none
 563  *
 564  * RETURN:      none
 565  *
 566  * DESCRIPTION: Disable events and free memory allocated for table storage.
 567  *
 568  ******************************************************************************/
 569
 570 void acpi_ev_terminate(void)
 571 {
 572         acpi_native_uint i;
 573         acpi_status status;
 574
 575         ACPI_FUNCTION_TRACE(ev_terminate);
 576
 577         if (acpi_gbl_events_initialized) {
 578                 /*
 579                  * Disable all event-related functionality.
 580                  * In all cases, on error, print a message but obviously we don't abort.
 581                  */
 582
 583                 /* Disable all fixed events */
 584
 585                 for (i = 0; i < ACPI_NUM_FIXED_EVENTS; i++) {
 586                         status = acpi_disable_event((u32) i, 0);
 587                         if (ACPI_FAILURE(status)) {
 588                                 ACPI_ERROR((AE_INFO,
 589                                             "Could not disable fixed event %d",
 590                                             (u32) i));
 591                         }
 592                 }
 593
 594                 /* Disable all GPEs in all GPE blocks */
 595
 596                 status = acpi_ev_walk_gpe_list(acpi_hw_disable_gpe_block);
 597
 598                 /* Remove SCI handler */
 599
 600                 status = acpi_ev_remove_sci_handler();
 601                 if (ACPI_FAILURE(status)) {
 602                         ACPI_ERROR((AE_INFO, "Could not remove SCI handler"));
 603                 }
 604
 605                 status = acpi_ev_remove_global_lock_handler();
 606                 if (ACPI_FAILURE(status)) {
 607                         ACPI_ERROR((AE_INFO,
 608                                     "Could not remove Global Lock handler"));
 609                 }
 610         }
 611
 612         /* Deallocate all handler objects installed within GPE info structs */
 613
 614         status = acpi_ev_walk_gpe_list(acpi_ev_delete_gpe_handlers);
 615
 616         /* Return to original mode if necessary */
 617
 618         if (acpi_gbl_original_mode == ACPI_SYS_MODE_LEGACY) {
 619                 status = acpi_disable();
 620                 if (ACPI_FAILURE(status)) {
 621                         ACPI_WARNING((AE_INFO, "AcpiDisable failed"));
 622                 }
 623         }
 624         return_VOID;
 625 }