evgpe.c 22.5 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788
/******************************************************************************
 *
 * Module Name: evgpe - General Purpose Event handling and dispatch
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2013, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <acpi/acpi.h>
#include "accommon.h"
#include "acevents.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evgpe")
#if (!ACPI_REDUCED_HARDWARE)	/* Entire module */
/* Local prototypes */
static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context);

static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_update_gpe_enable_mask
 *
 * PARAMETERS:  gpe_event_info          - GPE to update
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Updates GPE register enable mask based upon whether there are
 *              runtime references to this GPE
 *
 ******************************************************************************/

acpi_status
acpi_ev_update_gpe_enable_mask(struct acpi_gpe_event_info *gpe_event_info)
{
	struct acpi_gpe_register_info *gpe_register_info;
	u32 register_bit;

	ACPI_FUNCTION_TRACE(ev_update_gpe_enable_mask);

	gpe_register_info = gpe_event_info->register_info;
	if (!gpe_register_info) {
		return_ACPI_STATUS(AE_NOT_EXIST);
	}

	register_bit = acpi_hw_get_gpe_register_bit(gpe_event_info);

	/* Clear the run bit up front */

	ACPI_CLEAR_BIT(gpe_register_info->enable_for_run, register_bit);

	/* Set the mask bit only if there are references to this GPE */

	if (gpe_event_info->runtime_count) {
		ACPI_SET_BIT(gpe_register_info->enable_for_run,
			     (u8)register_bit);
	}

	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_enable_gpe
 *
 * PARAMETERS:  gpe_event_info  - GPE to enable
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Clear a GPE of stale events and enable it.
 *
 ******************************************************************************/
acpi_status acpi_ev_enable_gpe(struct acpi_gpe_event_info *gpe_event_info)
{
	acpi_status status;

	ACPI_FUNCTION_TRACE(ev_enable_gpe);

	/*
	 * We will only allow a GPE to be enabled if it has either an associated
	 * method (_Lxx/_Exx) or a handler, or is using the implicit notify
	 * feature. Otherwise, the GPE will be immediately disabled by
	 * acpi_ev_gpe_dispatch the first time it fires.
	 */
	if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
	    ACPI_GPE_DISPATCH_NONE) {
		return_ACPI_STATUS(AE_NO_HANDLER);
	}

	/* Clear the GPE (of stale events) */
	status = acpi_hw_clear_gpe(gpe_event_info);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Enable the requested GPE */

	status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_ENABLE);
	return_ACPI_STATUS(status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_add_gpe_reference
 *
 * PARAMETERS:  gpe_event_info          - Add a reference to this GPE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Add a reference to a GPE. On the first reference, the GPE is
 *              hardware-enabled.
 *
 ******************************************************************************/

acpi_status
acpi_ev_add_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
{
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE(ev_add_gpe_reference);

	if (gpe_event_info->runtime_count == ACPI_UINT8_MAX) {
		return_ACPI_STATUS(AE_LIMIT);
	}

	gpe_event_info->runtime_count++;
	if (gpe_event_info->runtime_count == 1) {

		/* Enable on first reference */

		status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
		if (ACPI_SUCCESS(status)) {
			status = acpi_ev_enable_gpe(gpe_event_info);
		}

		if (ACPI_FAILURE(status)) {
			gpe_event_info->runtime_count--;
		}
	}

	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_remove_gpe_reference
 *
 * PARAMETERS:  gpe_event_info          - Remove a reference to this GPE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Remove a reference to a GPE. When the last reference is
 *              removed, the GPE is hardware-disabled.
 *
 ******************************************************************************/

acpi_status
acpi_ev_remove_gpe_reference(struct acpi_gpe_event_info *gpe_event_info)
{
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE(ev_remove_gpe_reference);

	if (!gpe_event_info->runtime_count) {
		return_ACPI_STATUS(AE_LIMIT);
	}

	gpe_event_info->runtime_count--;
	if (!gpe_event_info->runtime_count) {

		/* Disable on last reference */

		status = acpi_ev_update_gpe_enable_mask(gpe_event_info);
		if (ACPI_SUCCESS(status)) {
			status =
			    acpi_hw_low_set_gpe(gpe_event_info,
						     ACPI_GPE_DISABLE);
		}

		if (ACPI_FAILURE(status)) {
			gpe_event_info->runtime_count++;
		}
	}

	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_low_get_gpe_info
 *
 * PARAMETERS:  gpe_number          - Raw GPE number
 *              gpe_block           - A GPE info block
 *
 * RETURN:      A GPE event_info struct. NULL if not a valid GPE (The gpe_number
 *              is not within the specified GPE block)
 *
 * DESCRIPTION: Returns the event_info struct associated with this GPE. This is
 *              the low-level implementation of ev_get_gpe_event_info.
 *
 ******************************************************************************/

struct acpi_gpe_event_info *acpi_ev_low_get_gpe_info(u32 gpe_number,
						     struct acpi_gpe_block_info
						     *gpe_block)
{
	u32 gpe_index;

	/*
	 * Validate that the gpe_number is within the specified gpe_block.
	 * (Two steps)
	 */
	if (!gpe_block || (gpe_number < gpe_block->block_base_number)) {
		return (NULL);
	}

	gpe_index = gpe_number - gpe_block->block_base_number;
	if (gpe_index >= gpe_block->gpe_count) {
		return (NULL);
	}

	return (&gpe_block->event_info[gpe_index]);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_get_gpe_event_info
 *
 * PARAMETERS:  gpe_device          - Device node. NULL for GPE0/GPE1
 *              gpe_number          - Raw GPE number
 *
 * RETURN:      A GPE event_info struct. NULL if not a valid GPE
 *
 * DESCRIPTION: Returns the event_info struct associated with this GPE.
 *              Validates the gpe_block and the gpe_number
 *
 *              Should be called only when the GPE lists are semaphore locked
 *              and not subject to change.
 *
 ******************************************************************************/

struct acpi_gpe_event_info *acpi_ev_get_gpe_event_info(acpi_handle gpe_device,
						       u32 gpe_number)
{
	union acpi_operand_object *obj_desc;
	struct acpi_gpe_event_info *gpe_info;
	u32 i;

	ACPI_FUNCTION_ENTRY();

	/* A NULL gpe_device means use the FADT-defined GPE block(s) */

	if (!gpe_device) {

		/* Examine GPE Block 0 and 1 (These blocks are permanent) */

		for (i = 0; i < ACPI_MAX_GPE_BLOCKS; i++) {
			gpe_info = acpi_ev_low_get_gpe_info(gpe_number,
							    acpi_gbl_gpe_fadt_blocks
							    [i]);
			if (gpe_info) {
				return (gpe_info);
			}
		}

		/* The gpe_number was not in the range of either FADT GPE block */

		return (NULL);
	}

	/* A Non-NULL gpe_device means this is a GPE Block Device */

	obj_desc =
	    acpi_ns_get_attached_object((struct acpi_namespace_node *)
					       gpe_device);
	if (!obj_desc || !obj_desc->device.gpe_block) {
		return (NULL);
	}

	return (acpi_ev_low_get_gpe_info
		(gpe_number, obj_desc->device.gpe_block));
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_gpe_detect
 *
 * PARAMETERS:  gpe_xrupt_list      - Interrupt block for this interrupt.
 *                                    Can have multiple GPE blocks attached.
 *
 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 *
 * DESCRIPTION: Detect if any GP events have occurred. This function is
 *              executed at interrupt level.
 *
 ******************************************************************************/

u32 acpi_ev_gpe_detect(struct acpi_gpe_xrupt_info * gpe_xrupt_list)
{
	acpi_status status;
	struct acpi_gpe_block_info *gpe_block;
	struct acpi_gpe_register_info *gpe_register_info;
	u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;
	u8 enabled_status_byte;
	u32 status_reg;
	u32 enable_reg;
	acpi_cpu_flags flags;
	u32 i;
	u32 j;

	ACPI_FUNCTION_NAME(ev_gpe_detect);

	/* Check for the case where there are no GPEs */

	if (!gpe_xrupt_list) {
		return (int_status);
	}

	/*
	 * We need to obtain the GPE lock for both the data structs and registers
	 * Note: Not necessary to obtain the hardware lock, since the GPE
	 * registers are owned by the gpe_lock.
	 */
	flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);

	/* Examine all GPE blocks attached to this interrupt level */

	gpe_block = gpe_xrupt_list->gpe_block_list_head;
	while (gpe_block) {
		/*
		 * Read all of the 8-bit GPE status and enable registers in this GPE
		 * block, saving all of them. Find all currently active GP events.
		 */
		for (i = 0; i < gpe_block->register_count; i++) {

			/* Get the next status/enable pair */

			gpe_register_info = &gpe_block->register_info[i];

			/*
			 * Optimization: If there are no GPEs enabled within this
			 * register, we can safely ignore the entire register.
			 */
			if (!(gpe_register_info->enable_for_run |
			      gpe_register_info->enable_for_wake)) {
				ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
						  "Ignore disabled registers for GPE%02X-GPE%02X: "
						  "RunEnable=%02X, WakeEnable=%02X\n",
						  gpe_register_info->
						  base_gpe_number,
						  gpe_register_info->
						  base_gpe_number +
						  (ACPI_GPE_REGISTER_WIDTH - 1),
						  gpe_register_info->
						  enable_for_run,
						  gpe_register_info->
						  enable_for_wake));
				continue;
			}

			/* Read the Status Register */

			status =
			    acpi_hw_read(&status_reg,
					 &gpe_register_info->status_address);
			if (ACPI_FAILURE(status)) {
				goto unlock_and_exit;
			}

			/* Read the Enable Register */

			status =
			    acpi_hw_read(&enable_reg,
					 &gpe_register_info->enable_address);
			if (ACPI_FAILURE(status)) {
				goto unlock_and_exit;
			}

			ACPI_DEBUG_PRINT((ACPI_DB_INTERRUPTS,
					  "Read registers for GPE%02X-GPE%02X: Status=%02X, Enable=%02X, "
					  "RunEnable=%02X, WakeEnable=%02X\n",
					  gpe_register_info->base_gpe_number,
					  gpe_register_info->base_gpe_number +
					  (ACPI_GPE_REGISTER_WIDTH - 1),
					  status_reg, enable_reg,
					  gpe_register_info->enable_for_run,
					  gpe_register_info->enable_for_wake));

			/* Check if there is anything active at all in this register */

			enabled_status_byte = (u8) (status_reg & enable_reg);
			if (!enabled_status_byte) {

				/* No active GPEs in this register, move on */

				continue;
			}

			/* Now look at the individual GPEs in this byte register */

			for (j = 0; j < ACPI_GPE_REGISTER_WIDTH; j++) {

				/* Examine one GPE bit */

				if (enabled_status_byte & (1 << j)) {
					/*
					 * Found an active GPE. Dispatch the event to a handler
					 * or method.
					 */
					int_status |=
					    acpi_ev_gpe_dispatch(gpe_block->
								 node,
								 &gpe_block->
						event_info[((acpi_size) i * ACPI_GPE_REGISTER_WIDTH) + j], j + gpe_register_info->base_gpe_number);
				}
			}
		}

		gpe_block = gpe_block->next;
	}

unlock_and_exit:

	acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
	return (int_status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_asynch_execute_gpe_method
 *
 * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 *
 * RETURN:      None
 *
 * DESCRIPTION: Perform the actual execution of a GPE control method. This
 *              function is called from an invocation of acpi_os_execute and
 *              therefore does NOT execute at interrupt level - so that
 *              the control method itself is not executed in the context of
 *              an interrupt handler.
 *
 ******************************************************************************/

static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
{
	struct acpi_gpe_event_info *gpe_event_info = context;
	acpi_status status;
	struct acpi_gpe_event_info *local_gpe_event_info;
	struct acpi_evaluate_info *info;
	struct acpi_gpe_notify_info *notify;

	ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);

	/* Allocate a local GPE block */

	local_gpe_event_info =
	    ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_event_info));
	if (!local_gpe_event_info) {
		ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY, "while handling a GPE"));
		return_VOID;
	}

	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		ACPI_FREE(local_gpe_event_info);
		return_VOID;
	}

	/* Must revalidate the gpe_number/gpe_block */

	if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
		status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
		ACPI_FREE(local_gpe_event_info);
		return_VOID;
	}

	/*
	 * Take a snapshot of the GPE info for this level - we copy the info to
	 * prevent a race condition with remove_handler/remove_block.
	 */
	ACPI_MEMCPY(local_gpe_event_info, gpe_event_info,
		    sizeof(struct acpi_gpe_event_info));

	status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		ACPI_FREE(local_gpe_event_info);
		return_VOID;
	}

	/* Do the correct dispatch - normal method or implicit notify */

	switch (local_gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
	case ACPI_GPE_DISPATCH_NOTIFY:
		/*
		 * Implicit notify.
		 * Dispatch a DEVICE_WAKE notify to the appropriate handler.
		 * NOTE: the request is queued for execution after this method
		 * completes. The notify handlers are NOT invoked synchronously
		 * from this thread -- because handlers may in turn run other
		 * control methods.
		 *
		 * June 2012: Expand implicit notify mechanism to support
		 * notifies on multiple device objects.
		 */
		notify = local_gpe_event_info->dispatch.notify_list;
		while (ACPI_SUCCESS(status) && notify) {
			status =
			    acpi_ev_queue_notify_request(notify->device_node,
							 ACPI_NOTIFY_DEVICE_WAKE);

			notify = notify->next;
		}

		break;

	case ACPI_GPE_DISPATCH_METHOD:

		/* Allocate the evaluation information block */

		info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
		if (!info) {
			status = AE_NO_MEMORY;
		} else {
			/*
			 * Invoke the GPE Method (_Lxx, _Exx) i.e., evaluate the
			 * _Lxx/_Exx control method that corresponds to this GPE
			 */
			info->prefix_node =
			    local_gpe_event_info->dispatch.method_node;
			info->flags = ACPI_IGNORE_RETURN_VALUE;

			status = acpi_ns_evaluate(info);
			ACPI_FREE(info);
		}

		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"while evaluating GPE method [%4.4s]",
					acpi_ut_get_node_name
					(local_gpe_event_info->dispatch.
					 method_node)));
		}
		break;

	default:

		return_VOID;	/* Should never happen */
	}

	/* Defer enabling of GPE until all notify handlers are done */

	status = acpi_os_execute(OSL_NOTIFY_HANDLER,
				 acpi_ev_asynch_enable_gpe,
				 local_gpe_event_info);
	if (ACPI_FAILURE(status)) {
		ACPI_FREE(local_gpe_event_info);
	}
	return_VOID;
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_asynch_enable_gpe
 *
 * PARAMETERS:  Context (gpe_event_info) - Info for this GPE
 *              Callback from acpi_os_execute
 *
 * RETURN:      None
 *
 * DESCRIPTION: Asynchronous clear/enable for GPE. This allows the GPE to
 *              complete (i.e., finish execution of Notify)
 *
 ******************************************************************************/

static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context)
{
	struct acpi_gpe_event_info *gpe_event_info = context;

	(void)acpi_ev_finish_gpe(gpe_event_info);

	ACPI_FREE(gpe_event_info);
	return;
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_finish_gpe
 *
 * PARAMETERS:  gpe_event_info      - Info for this GPE
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Clear/Enable a GPE. Common code that is used after execution
 *              of a GPE method or a synchronous or asynchronous GPE handler.
 *
 ******************************************************************************/

acpi_status acpi_ev_finish_gpe(struct acpi_gpe_event_info *gpe_event_info)
{
	acpi_status status;

	if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
	    ACPI_GPE_LEVEL_TRIGGERED) {
		/*
		 * GPE is level-triggered, we clear the GPE status bit after
		 * handling the event.
		 */
		status = acpi_hw_clear_gpe(gpe_event_info);
		if (ACPI_FAILURE(status)) {
			return (status);
		}
	}

	/*
	 * Enable this GPE, conditionally. This means that the GPE will
	 * only be physically enabled if the enable_for_run bit is set
	 * in the event_info.
	 */
	(void)acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_CONDITIONAL_ENABLE);
	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_gpe_dispatch
 *
 * PARAMETERS:  gpe_device      - Device node. NULL for GPE0/GPE1
 *              gpe_event_info  - Info for this GPE
 *              gpe_number      - Number relative to the parent GPE block
 *
 * RETURN:      INTERRUPT_HANDLED or INTERRUPT_NOT_HANDLED
 *
 * DESCRIPTION: Dispatch a General Purpose Event to either a function (e.g. EC)
 *              or method (e.g. _Lxx/_Exx) handler.
 *
 *              This function executes at interrupt level.
 *
 ******************************************************************************/

u32
acpi_ev_gpe_dispatch(struct acpi_namespace_node *gpe_device,
		    struct acpi_gpe_event_info *gpe_event_info, u32 gpe_number)
{
	acpi_status status;
	u32 return_value;

	ACPI_FUNCTION_TRACE(ev_gpe_dispatch);

	/* Invoke global event handler if present */

	acpi_gpe_count++;
	if (acpi_gbl_global_event_handler) {
		acpi_gbl_global_event_handler(ACPI_EVENT_TYPE_GPE, gpe_device,
					      gpe_number,
					      acpi_gbl_global_event_handler_context);
	}

	/*
	 * If edge-triggered, clear the GPE status bit now. Note that
	 * level-triggered events are cleared after the GPE is serviced.
	 */
	if ((gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK) ==
	    ACPI_GPE_EDGE_TRIGGERED) {
		status = acpi_hw_clear_gpe(gpe_event_info);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"Unable to clear GPE%02X", gpe_number));
			return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
		}
	}

	/*
	 * Always disable the GPE so that it does not keep firing before
	 * any asynchronous activity completes (either from the execution
	 * of a GPE method or an asynchronous GPE handler.)
	 *
	 * If there is no handler or method to run, just disable the
	 * GPE and leave it disabled permanently to prevent further such
	 * pointless events from firing.
	 */
	status = acpi_hw_low_set_gpe(gpe_event_info, ACPI_GPE_DISABLE);
	if (ACPI_FAILURE(status)) {
		ACPI_EXCEPTION((AE_INFO, status,
				"Unable to disable GPE%02X", gpe_number));
		return_UINT32(ACPI_INTERRUPT_NOT_HANDLED);
	}

	/*
	 * Dispatch the GPE to either an installed handler or the control
	 * method associated with this GPE (_Lxx or _Exx). If a handler
	 * exists, we invoke it and do not attempt to run the method.
	 * If there is neither a handler nor a method, leave the GPE
	 * disabled.
	 */
	switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
	case ACPI_GPE_DISPATCH_HANDLER:

		/* Invoke the installed handler (at interrupt level) */

		return_value =
		    gpe_event_info->dispatch.handler->address(gpe_device,
							      gpe_number,
							      gpe_event_info->
							      dispatch.handler->
							      context);

		/* If requested, clear (if level-triggered) and reenable the GPE */

		if (return_value & ACPI_REENABLE_GPE) {
			(void)acpi_ev_finish_gpe(gpe_event_info);
		}
		break;

	case ACPI_GPE_DISPATCH_METHOD:
	case ACPI_GPE_DISPATCH_NOTIFY:
		/*
		 * Execute the method associated with the GPE
		 * NOTE: Level-triggered GPEs are cleared after the method completes.
		 */
		status = acpi_os_execute(OSL_GPE_HANDLER,
					 acpi_ev_asynch_execute_gpe_method,
					 gpe_event_info);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"Unable to queue handler for GPE%02X - event disabled",
					gpe_number));
		}
		break;

	default:
		/*
		 * No handler or method to run!
		 * 03/2010: This case should no longer be possible. We will not allow
		 * a GPE to be enabled if it has no handler or method.
		 */
		ACPI_ERROR((AE_INFO,
			    "No handler or method for GPE%02X, disabling event",
			    gpe_number));

		break;
	}

	return_UINT32(ACPI_INTERRUPT_HANDLED);
}

#endif				/* !ACPI_REDUCED_HARDWARE */