nsinit.c 17.8 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6 7
/******************************************************************************
 *
 * Module Name: nsinit - namespace initialization
 *
 *****************************************************************************/

/*
8
 * Copyright (C) 2000 - 2012, Intel Corp.
L
Linus Torvalds 已提交
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
 * 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>
L
Len Brown 已提交
45 46 47 48
#include "accommon.h"
#include "acnamesp.h"
#include "acdispat.h"
#include "acinterp.h"
49
#include <linux/nmi.h>
L
Linus Torvalds 已提交
50 51

#define _COMPONENT          ACPI_NAMESPACE
L
Len Brown 已提交
52
ACPI_MODULE_NAME("nsinit")
L
Linus Torvalds 已提交
53

R
Robert Moore 已提交
54 55
/* Local prototypes */
static acpi_status
L
Len Brown 已提交
56 57
acpi_ns_init_one_object(acpi_handle obj_handle,
			u32 level, void *context, void **return_value);
R
Robert Moore 已提交
58 59

static acpi_status
L
Len Brown 已提交
60 61
acpi_ns_init_one_device(acpi_handle obj_handle,
			u32 nesting_level, void *context, void **return_value);
L
Linus Torvalds 已提交
62

B
Bob Moore 已提交
63 64 65 66
static acpi_status
acpi_ns_find_ini_methods(acpi_handle obj_handle,
			 u32 nesting_level, void *context, void **return_value);

L
Linus Torvalds 已提交
67 68 69 70 71 72 73 74 75 76 77 78 79
/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_initialize_objects
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Walk the entire namespace and perform any necessary
 *              initialization on the objects found therein
 *
 ******************************************************************************/

L
Len Brown 已提交
80
acpi_status acpi_ns_initialize_objects(void)
L
Linus Torvalds 已提交
81
{
L
Len Brown 已提交
82 83
	acpi_status status;
	struct acpi_init_walk_info info;
L
Linus Torvalds 已提交
84

B
Bob Moore 已提交
85
	ACPI_FUNCTION_TRACE(ns_initialize_objects);
L
Linus Torvalds 已提交
86

L
Len Brown 已提交
87 88 89 90
	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
			  "**** Starting initialization of namespace objects ****\n"));
	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
			      "Completing Region/Field/Buffer/Package initialization:"));
L
Linus Torvalds 已提交
91 92 93

	/* Set all init info to zero */

L
Len Brown 已提交
94
	ACPI_MEMSET(&info, 0, sizeof(struct acpi_init_walk_info));
L
Linus Torvalds 已提交
95 96 97

	/* Walk entire namespace from the supplied root */

L
Len Brown 已提交
98
	status = acpi_walk_namespace(ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
99
				     ACPI_UINT32_MAX, acpi_ns_init_one_object, NULL,
L
Len Brown 已提交
100 101
				     &info, NULL);
	if (ACPI_FAILURE(status)) {
B
Bob Moore 已提交
102
		ACPI_EXCEPTION((AE_INFO, status, "During WalkNamespace"));
L
Linus Torvalds 已提交
103 104
	}

L
Len Brown 已提交
105
	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
106 107
			      "\nInitialized %u/%u Regions %u/%u Fields %u/%u "
			      "Buffers %u/%u Packages (%u nodes)\n",
L
Len Brown 已提交
108 109 110 111 112
			      info.op_region_init, info.op_region_count,
			      info.field_init, info.field_count,
			      info.buffer_init, info.buffer_count,
			      info.package_init, info.package_count,
			      info.object_count));
L
Linus Torvalds 已提交
113

L
Len Brown 已提交
114
	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
115
			  "%u Control Methods found\n", info.method_count));
L
Len Brown 已提交
116
	ACPI_DEBUG_PRINT((ACPI_DB_DISPATCH,
117
			  "%u Op Regions found\n", info.op_region_count));
L
Linus Torvalds 已提交
118

L
Len Brown 已提交
119
	return_ACPI_STATUS(AE_OK);
L
Linus Torvalds 已提交
120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_initialize_devices
 *
 * PARAMETERS:  None
 *
 * RETURN:      acpi_status
 *
 * DESCRIPTION: Walk the entire namespace and initialize all ACPI devices.
 *              This means running _INI on all present devices.
 *
 *              Note: We install PCI config space handler on region access,
 *              not here.
 *
 ******************************************************************************/

L
Len Brown 已提交
138
acpi_status acpi_ns_initialize_devices(void)
L
Linus Torvalds 已提交
139
{
L
Len Brown 已提交
140 141
	acpi_status status;
	struct acpi_device_walk_info info;
L
Linus Torvalds 已提交
142

B
Bob Moore 已提交
143
	ACPI_FUNCTION_TRACE(ns_initialize_devices);
L
Linus Torvalds 已提交
144 145 146 147 148 149 150

	/* Init counters */

	info.device_count = 0;
	info.num_STA = 0;
	info.num_INI = 0;

L
Len Brown 已提交
151
	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
152 153
			      "Initializing Device/Processor/Thermal objects "
			      "by executing _INI methods:"));
B
Bob Moore 已提交
154 155

	/* Tree analysis: find all subtrees that contain _INI methods */
L
Linus Torvalds 已提交
156

B
Bob Moore 已提交
157 158
	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
					ACPI_UINT32_MAX, FALSE,
159 160
					acpi_ns_find_ini_methods, NULL, &info,
					NULL);
L
Len Brown 已提交
161
	if (ACPI_FAILURE(status)) {
B
Bob Moore 已提交
162 163 164 165 166 167 168 169 170 171
		goto error_exit;
	}

	/* Allocate the evaluation information block */

	info.evaluate_info =
	    ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
	if (!info.evaluate_info) {
		status = AE_NO_MEMORY;
		goto error_exit;
L
Linus Torvalds 已提交
172 173
	}

174 175 176 177 178 179 180 181 182 183 184 185 186 187 188
	/*
	 * Execute the "global" _INI method that may appear at the root. This
	 * support is provided for Windows compatibility (Vista+) and is not
	 * part of the ACPI specification.
	 */
	info.evaluate_info->prefix_node = acpi_gbl_root_node;
	info.evaluate_info->pathname = METHOD_NAME__INI;
	info.evaluate_info->parameters = NULL;
	info.evaluate_info->flags = ACPI_IGNORE_RETURN_VALUE;

	status = acpi_ns_evaluate(info.evaluate_info);
	if (ACPI_SUCCESS(status)) {
		info.num_INI++;
	}

B
Bob Moore 已提交
189
	/* Walk namespace to execute all _INIs on present devices */
L
Linus Torvalds 已提交
190

L
Len Brown 已提交
191
	status = acpi_ns_walk_namespace(ACPI_TYPE_ANY, ACPI_ROOT_OBJECT,
B
Bob Moore 已提交
192
					ACPI_UINT32_MAX, FALSE,
193 194
					acpi_ns_init_one_device, NULL, &info,
					NULL);
B
Bob Moore 已提交
195

196 197 198 199 200 201 202 203 204
	/*
	 * Any _OSI requests should be completed by now. If the BIOS has
	 * requested any Windows OSI strings, we will always truncate
	 * I/O addresses to 16 bits -- for Windows compatibility.
	 */
	if (acpi_gbl_osi_data >= ACPI_OSI_WIN_2000) {
		acpi_gbl_truncate_io_addresses = TRUE;
	}

B
Bob Moore 已提交
205
	ACPI_FREE(info.evaluate_info);
L
Len Brown 已提交
206
	if (ACPI_FAILURE(status)) {
B
Bob Moore 已提交
207
		goto error_exit;
L
Linus Torvalds 已提交
208 209
	}

L
Len Brown 已提交
210
	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT,
211 212
			      "\nExecuted %u _INI methods requiring %u _STA executions "
			      "(examined %u objects)\n",
B
Bob Moore 已提交
213
			      info.num_INI, info.num_STA, info.device_count));
L
Linus Torvalds 已提交
214

L
Len Brown 已提交
215
	return_ACPI_STATUS(status);
B
Bob Moore 已提交
216 217 218 219

      error_exit:
	ACPI_EXCEPTION((AE_INFO, status, "During device initialization"));
	return_ACPI_STATUS(status);
L
Linus Torvalds 已提交
220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_init_one_object
 *
 * PARAMETERS:  obj_handle      - Node
 *              Level           - Current nesting level
 *              Context         - Points to a init info struct
 *              return_value    - Not used
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Callback from acpi_walk_namespace. Invoked for every object
 *              within the  namespace.
 *
 *              Currently, the only objects that require initialization are:
 *              1) Methods
 *              2) Op Regions
 *
 ******************************************************************************/

R
Robert Moore 已提交
242
static acpi_status
L
Len Brown 已提交
243 244
acpi_ns_init_one_object(acpi_handle obj_handle,
			u32 level, void *context, void **return_value)
L
Linus Torvalds 已提交
245
{
L
Len Brown 已提交
246
	acpi_object_type type;
247
	acpi_status status = AE_OK;
L
Len Brown 已提交
248 249 250 251 252
	struct acpi_init_walk_info *info =
	    (struct acpi_init_walk_info *)context;
	struct acpi_namespace_node *node =
	    (struct acpi_namespace_node *)obj_handle;
	union acpi_operand_object *obj_desc;
L
Linus Torvalds 已提交
253

B
Bob Moore 已提交
254
	ACPI_FUNCTION_NAME(ns_init_one_object);
L
Linus Torvalds 已提交
255 256 257 258 259

	info->object_count++;

	/* And even then, we are only interested in a few object types */

L
Len Brown 已提交
260 261
	type = acpi_ns_get_type(obj_handle);
	obj_desc = acpi_ns_get_attached_object(node);
L
Linus Torvalds 已提交
262 263 264 265 266 267 268 269 270 271 272 273 274 275 276
	if (!obj_desc) {
		return (AE_OK);
	}

	/* Increment counters for object types we are looking for */

	switch (type) {
	case ACPI_TYPE_REGION:
		info->op_region_count++;
		break;

	case ACPI_TYPE_BUFFER_FIELD:
		info->field_count++;
		break;

277 278 279 280
	case ACPI_TYPE_LOCAL_BANK_FIELD:
		info->field_count++;
		break;

L
Linus Torvalds 已提交
281 282 283 284 285 286 287 288 289 290 291 292 293 294
	case ACPI_TYPE_BUFFER:
		info->buffer_count++;
		break;

	case ACPI_TYPE_PACKAGE:
		info->package_count++;
		break;

	default:

		/* No init required, just exit now */
		return (AE_OK);
	}

295 296
	/* If the object is already initialized, nothing else to do */

L
Linus Torvalds 已提交
297 298 299 300
	if (obj_desc->common.flags & AOPOBJ_DATA_VALID) {
		return (AE_OK);
	}

301 302
	/* Must lock the interpreter before executing AML code */

303
	acpi_ex_enter_interpreter();
L
Linus Torvalds 已提交
304 305 306 307 308 309 310 311 312

	/*
	 * Each of these types can contain executable AML code within the
	 * declaration.
	 */
	switch (type) {
	case ACPI_TYPE_REGION:

		info->op_region_init++;
L
Len Brown 已提交
313
		status = acpi_ds_get_region_arguments(obj_desc);
L
Linus Torvalds 已提交
314 315 316 317 318
		break;

	case ACPI_TYPE_BUFFER_FIELD:

		info->field_init++;
L
Len Brown 已提交
319
		status = acpi_ds_get_buffer_field_arguments(obj_desc);
L
Linus Torvalds 已提交
320 321
		break;

322 323 324 325 326 327
	case ACPI_TYPE_LOCAL_BANK_FIELD:

		info->field_init++;
		status = acpi_ds_get_bank_field_arguments(obj_desc);
		break;

L
Linus Torvalds 已提交
328 329 330
	case ACPI_TYPE_BUFFER:

		info->buffer_init++;
L
Len Brown 已提交
331
		status = acpi_ds_get_buffer_arguments(obj_desc);
L
Linus Torvalds 已提交
332 333 334 335 336
		break;

	case ACPI_TYPE_PACKAGE:

		info->package_init++;
L
Len Brown 已提交
337
		status = acpi_ds_get_package_arguments(obj_desc);
L
Linus Torvalds 已提交
338 339 340 341 342 343 344
		break;

	default:
		/* No other types can get here */
		break;
	}

L
Len Brown 已提交
345
	if (ACPI_FAILURE(status)) {
B
Bob Moore 已提交
346 347 348 349
		ACPI_EXCEPTION((AE_INFO, status,
				"Could not execute arguments for [%4.4s] (%s)",
				acpi_ut_get_node_name(node),
				acpi_ut_get_type_name(type)));
L
Linus Torvalds 已提交
350 351 352 353 354 355 356
	}

	/*
	 * Print a dot for each object unless we are going to print the entire
	 * pathname
	 */
	if (!(acpi_dbg_level & ACPI_LV_INIT_NAMES)) {
L
Len Brown 已提交
357
		ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT, "."));
L
Linus Torvalds 已提交
358 359 360 361 362 363
	}

	/*
	 * We ignore errors from above, and always return OK, since we don't want
	 * to abort the walk on any single error.
	 */
L
Len Brown 已提交
364
	acpi_ex_exit_interpreter();
L
Linus Torvalds 已提交
365 366 367
	return (AE_OK);
}

B
Bob Moore 已提交
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
/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_find_ini_methods
 *
 * PARAMETERS:  acpi_walk_callback
 *
 * RETURN:      acpi_status
 *
 * DESCRIPTION: Called during namespace walk. Finds objects named _INI under
 *              device/processor/thermal objects, and marks the entire subtree
 *              with a SUBTREE_HAS_INI flag. This flag is used during the
 *              subsequent device initialization walk to avoid entire subtrees
 *              that do not contain an _INI.
 *
 ******************************************************************************/

static acpi_status
acpi_ns_find_ini_methods(acpi_handle obj_handle,
			 u32 nesting_level, void *context, void **return_value)
{
	struct acpi_device_walk_info *info =
	    ACPI_CAST_PTR(struct acpi_device_walk_info, context);
	struct acpi_namespace_node *node;
	struct acpi_namespace_node *parent_node;

	/* Keep count of device/processor/thermal objects */

	node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
	if ((node->type == ACPI_TYPE_DEVICE) ||
	    (node->type == ACPI_TYPE_PROCESSOR) ||
	    (node->type == ACPI_TYPE_THERMAL)) {
		info->device_count++;
		return (AE_OK);
	}

	/* We are only looking for methods named _INI */

	if (!ACPI_COMPARE_NAME(node->name.ascii, METHOD_NAME__INI)) {
		return (AE_OK);
	}

	/*
	 * The only _INI methods that we care about are those that are
	 * present under Device, Processor, and Thermal objects.
	 */
413
	parent_node = node->parent;
B
Bob Moore 已提交
414 415 416 417 418 419 420 421 422
	switch (parent_node->type) {
	case ACPI_TYPE_DEVICE:
	case ACPI_TYPE_PROCESSOR:
	case ACPI_TYPE_THERMAL:

		/* Mark parent and bubble up the INI present flag to the root */

		while (parent_node) {
			parent_node->flags |= ANOBJ_SUBTREE_HAS_INI;
423
			parent_node = parent_node->parent;
B
Bob Moore 已提交
424 425 426 427 428 429 430 431 432 433
		}
		break;

	default:
		break;
	}

	return (AE_OK);
}

L
Linus Torvalds 已提交
434 435 436 437 438 439 440 441 442 443 444 445 446 447
/*******************************************************************************
 *
 * FUNCTION:    acpi_ns_init_one_device
 *
 * PARAMETERS:  acpi_walk_callback
 *
 * RETURN:      acpi_status
 *
 * DESCRIPTION: This is called once per device soon after ACPI is enabled
 *              to initialize each device. It determines if the device is
 *              present, and if so, calls _INI.
 *
 ******************************************************************************/

R
Robert Moore 已提交
448
static acpi_status
L
Len Brown 已提交
449 450
acpi_ns_init_one_device(acpi_handle obj_handle,
			u32 nesting_level, void *context, void **return_value)
L
Linus Torvalds 已提交
451
{
B
Bob Moore 已提交
452
	struct acpi_device_walk_info *walk_info =
B
Bob Moore 已提交
453
	    ACPI_CAST_PTR(struct acpi_device_walk_info, context);
B
Bob Moore 已提交
454
	struct acpi_evaluate_info *info = walk_info->evaluate_info;
L
Len Brown 已提交
455 456
	u32 flags;
	acpi_status status;
B
Bob Moore 已提交
457
	struct acpi_namespace_node *device_node;
L
Linus Torvalds 已提交
458

B
Bob Moore 已提交
459
	ACPI_FUNCTION_TRACE(ns_init_one_device);
L
Linus Torvalds 已提交
460

B
Bob Moore 已提交
461
	/* We are interested in Devices, Processors and thermal_zones only */
L
Linus Torvalds 已提交
462

B
Bob Moore 已提交
463
	device_node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
B
Bob Moore 已提交
464 465 466
	if ((device_node->type != ACPI_TYPE_DEVICE) &&
	    (device_node->type != ACPI_TYPE_PROCESSOR) &&
	    (device_node->type != ACPI_TYPE_THERMAL)) {
L
Len Brown 已提交
467
		return_ACPI_STATUS(AE_OK);
L
Linus Torvalds 已提交
468 469 470
	}

	/*
B
Bob Moore 已提交
471 472 473 474 475
	 * Because of an earlier namespace analysis, all subtrees that contain an
	 * _INI method are tagged.
	 *
	 * If this device subtree does not contain any _INI methods, we
	 * can exit now and stop traversing this entire subtree.
B
Bob Moore 已提交
476
	 */
B
Bob Moore 已提交
477 478
	if (!(device_node->flags & ANOBJ_SUBTREE_HAS_INI)) {
		return_ACPI_STATUS(AE_CTRL_DEPTH);
B
Bob Moore 已提交
479 480 481
	}

	/*
B
Bob Moore 已提交
482 483 484 485 486 487 488 489 490
	 * Run _STA to determine if this device is present and functioning. We
	 * must know this information for two important reasons (from ACPI spec):
	 *
	 * 1) We can only run _INI if the device is present.
	 * 2) We must abort the device tree walk on this subtree if the device is
	 *    not present and is not functional (we will not examine the children)
	 *
	 * The _STA method is not required to be present under the device, we
	 * assume the device is present if _STA does not exist.
L
Linus Torvalds 已提交
491
	 */
B
Bob Moore 已提交
492 493
	ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
			(ACPI_TYPE_METHOD, device_node, METHOD_NAME__STA));
L
Linus Torvalds 已提交
494

B
Bob Moore 已提交
495
	status = acpi_ut_execute_STA(device_node, &flags);
L
Len Brown 已提交
496
	if (ACPI_FAILURE(status)) {
B
Bob Moore 已提交
497

B
Bob Moore 已提交
498
		/* Ignore error and move on to next device */
L
Linus Torvalds 已提交
499

B
Bob Moore 已提交
500 501
		return_ACPI_STATUS(AE_OK);
	}
L
Linus Torvalds 已提交
502

B
Bob Moore 已提交
503 504 505 506 507 508 509 510 511 512
	/*
	 * Flags == -1 means that _STA was not found. In this case, we assume that
	 * the device is both present and functional.
	 *
	 * From the ACPI spec, description of _STA:
	 *
	 * "If a device object (including the processor object) does not have an
	 * _STA object, then OSPM assumes that all of the above bits are set (in
	 * other words, the device is present, ..., and functioning)"
	 */
B
Bob Moore 已提交
513
	if (flags != ACPI_UINT32_MAX) {
B
Bob Moore 已提交
514
		walk_info->num_STA++;
B
Bob Moore 已提交
515
	}
L
Linus Torvalds 已提交
516

B
Bob Moore 已提交
517 518 519 520 521 522
	/*
	 * Examine the PRESENT and FUNCTIONING status bits
	 *
	 * Note: ACPI spec does not seem to specify behavior for the present but
	 * not functioning case, so we assume functioning if present.
	 */
B
Bob Moore 已提交
523
	if (!(flags & ACPI_STA_DEVICE_PRESENT)) {
B
Bob Moore 已提交
524

B
Bob Moore 已提交
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
		/* Device is not present, we must examine the Functioning bit */

		if (flags & ACPI_STA_DEVICE_FUNCTIONING) {
			/*
			 * Device is not present but is "functioning". In this case,
			 * we will not run _INI, but we continue to examine the children
			 * of this device.
			 *
			 * From the ACPI spec, description of _STA: (Note - no mention
			 * of whether to run _INI or not on the device in question)
			 *
			 * "_STA may return bit 0 clear (not present) with bit 3 set
			 * (device is functional). This case is used to indicate a valid
			 * device for which no device driver should be loaded (for example,
			 * a bridge device.) Children of this device may be present and
			 * valid. OSPM should continue enumeration below a device whose
			 * _STA returns this bit combination"
			 */
			return_ACPI_STATUS(AE_OK);
		} else {
			/*
			 * Device is not present and is not functioning. We must abort the
			 * walk of this subtree immediately -- don't look at the children
			 * of such a device.
			 *
			 * From the ACPI spec, description of _INI:
			 *
			 * "If the _STA method indicates that the device is not present,
			 * OSPM will not run the _INI and will not examine the children
			 * of the device for _INI methods"
			 */
			return_ACPI_STATUS(AE_CTRL_DEPTH);
		}
L
Linus Torvalds 已提交
558 559 560
	}

	/*
B
Bob Moore 已提交
561 562 563 564 565
	 * The device is present or is assumed present if no _STA exists.
	 * Run the _INI if it exists (not required to exist)
	 *
	 * Note: We know there is an _INI within this subtree, but it may not be
	 * under this particular device, it may be lower in the branch.
L
Linus Torvalds 已提交
566
	 */
B
Bob Moore 已提交
567 568
	ACPI_DEBUG_EXEC(acpi_ut_display_init_pathname
			(ACPI_TYPE_METHOD, device_node, METHOD_NAME__INI));
L
Linus Torvalds 已提交
569

B
Bob Moore 已提交
570 571 572 573
	info->prefix_node = device_node;
	info->pathname = METHOD_NAME__INI;
	info->parameters = NULL;
	info->flags = ACPI_IGNORE_RETURN_VALUE;
L
Linus Torvalds 已提交
574

575 576 577 578 579
	/*
	 * Some hardware relies on this being executed as atomically
	 * as possible (without an NMI being received in the middle of
	 * this) - so disable NMIs and initialize the device:
	 */
B
Bob Moore 已提交
580
	status = acpi_ns_evaluate(info);
581

B
Bob Moore 已提交
582
	if (ACPI_SUCCESS(status)) {
B
Bob Moore 已提交
583
		walk_info->num_INI++;
L
Linus Torvalds 已提交
584

B
Bob Moore 已提交
585 586 587 588
		if ((acpi_dbg_level <= ACPI_LV_ALL_EXCEPTIONS) &&
		    (!(acpi_dbg_level & ACPI_LV_INFO))) {
			ACPI_DEBUG_PRINT_RAW((ACPI_DB_INIT, "."));
		}
L
Linus Torvalds 已提交
589
	}
B
Bob Moore 已提交
590 591
#ifdef ACPI_DEBUG_OUTPUT
	else if (status != AE_NOT_FOUND) {
L
Linus Torvalds 已提交
592

B
Bob Moore 已提交
593 594
		/* Ignore error and move on to next device */

B
Bob Moore 已提交
595 596
		char *scope_name =
		    acpi_ns_get_external_pathname(info->resolved_node);
B
Bob Moore 已提交
597

B
Bob Moore 已提交
598 599 600 601 602
		ACPI_EXCEPTION((AE_INFO, status, "during %s._INI execution",
				scope_name));
		ACPI_FREE(scope_name);
	}
#endif
L
Linus Torvalds 已提交
603

B
Bob Moore 已提交
604 605 606 607
	/* Ignore errors from above */

	status = AE_OK;

B
Bob Moore 已提交
608 609 610 611
	/*
	 * The _INI method has been run if present; call the Global Initialization
	 * Handler for this device.
	 */
B
Bob Moore 已提交
612
	if (acpi_gbl_init_handler) {
L
Len Brown 已提交
613
		status =
B
Bob Moore 已提交
614
		    acpi_gbl_init_handler(device_node, ACPI_INIT_DEVICE_INI);
L
Linus Torvalds 已提交
615 616
	}

B
Bob Moore 已提交
617
	return_ACPI_STATUS(status);
L
Linus Torvalds 已提交
618
}