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v3.1
  1/*
  2 *  acpi_power.c - ACPI Bus Power Management ($Revision: 39 $)
  3 *
  4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
  5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
  6 *
  7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  8 *
  9 *  This program is free software; you can redistribute it and/or modify
 10 *  it under the terms of the GNU General Public License as published by
 11 *  the Free Software Foundation; either version 2 of the License, or (at
 12 *  your option) any later version.
 13 *
 14 *  This program is distributed in the hope that it will be useful, but
 15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 17 *  General Public License for more details.
 18 *
 19 *  You should have received a copy of the GNU General Public License along
 20 *  with this program; if not, write to the Free Software Foundation, Inc.,
 21 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 22 *
 23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 24 */
 25
 26/*
 27 * ACPI power-managed devices may be controlled in two ways:
 28 * 1. via "Device Specific (D-State) Control"
 29 * 2. via "Power Resource Control".
 30 * This module is used to manage devices relying on Power Resource Control.
 31 * 
 32 * An ACPI "power resource object" describes a software controllable power
 33 * plane, clock plane, or other resource used by a power managed device.
 34 * A device may rely on multiple power resources, and a power resource
 35 * may be shared by multiple devices.
 36 */
 37
 38#include <linux/kernel.h>
 39#include <linux/module.h>
 40#include <linux/init.h>
 41#include <linux/types.h>
 42#include <linux/slab.h>
 
 43#include <acpi/acpi_bus.h>
 44#include <acpi/acpi_drivers.h>
 45#include "sleep.h"
 
 46
 47#define PREFIX "ACPI: "
 48
 49#define _COMPONENT			ACPI_POWER_COMPONENT
 50ACPI_MODULE_NAME("power");
 51#define ACPI_POWER_CLASS		"power_resource"
 52#define ACPI_POWER_DEVICE_NAME		"Power Resource"
 53#define ACPI_POWER_FILE_INFO		"info"
 54#define ACPI_POWER_FILE_STATUS		"state"
 55#define ACPI_POWER_RESOURCE_STATE_OFF	0x00
 56#define ACPI_POWER_RESOURCE_STATE_ON	0x01
 57#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
 58
 59static int acpi_power_add(struct acpi_device *device);
 60static int acpi_power_remove(struct acpi_device *device, int type);
 61static int acpi_power_resume(struct acpi_device *device);
 62
 63static const struct acpi_device_id power_device_ids[] = {
 64	{ACPI_POWER_HID, 0},
 65	{"", 0},
 66};
 67MODULE_DEVICE_TABLE(acpi, power_device_ids);
 68
 69static struct acpi_driver acpi_power_driver = {
 70	.name = "power",
 71	.class = ACPI_POWER_CLASS,
 72	.ids = power_device_ids,
 73	.ops = {
 74		.add = acpi_power_add,
 75		.remove = acpi_power_remove,
 76		.resume = acpi_power_resume,
 77		},
 78};
 79
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 80struct acpi_power_resource {
 81	struct acpi_device * device;
 82	acpi_bus_id name;
 83	u32 system_level;
 84	u32 order;
 85	unsigned int ref_count;
 86	struct mutex resource_lock;
 
 
 
 
 87};
 88
 89static struct list_head acpi_power_resource_list;
 90
 91/* --------------------------------------------------------------------------
 92                             Power Resource Management
 93   -------------------------------------------------------------------------- */
 94
 95static int
 96acpi_power_get_context(acpi_handle handle,
 97		       struct acpi_power_resource **resource)
 98{
 99	int result = 0;
100	struct acpi_device *device = NULL;
101
102
103	if (!resource)
104		return -ENODEV;
105
106	result = acpi_bus_get_device(handle, &device);
107	if (result) {
108		printk(KERN_WARNING PREFIX "Getting context [%p]\n", handle);
109		return result;
110	}
111
112	*resource = acpi_driver_data(device);
113	if (!*resource)
114		return -ENODEV;
115
116	return 0;
117}
118
119static int acpi_power_get_state(acpi_handle handle, int *state)
120{
121	acpi_status status = AE_OK;
122	unsigned long long sta = 0;
123	char node_name[5];
124	struct acpi_buffer buffer = { sizeof(node_name), node_name };
125
126
127	if (!handle || !state)
128		return -EINVAL;
129
130	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
131	if (ACPI_FAILURE(status))
132		return -ENODEV;
133
134	*state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
135			      ACPI_POWER_RESOURCE_STATE_OFF;
136
137	acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
138
139	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
140			  node_name,
141				*state ? "on" : "off"));
142
143	return 0;
144}
145
146static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
147{
148	int cur_state;
149	int i = 0;
150
151	if (!list || !state)
152		return -EINVAL;
153
154	/* The state of the list is 'on' IFF all resources are 'on'. */
155
156	for (i = 0; i < list->count; i++) {
157		struct acpi_power_resource *resource;
158		acpi_handle handle = list->handles[i];
159		int result;
160
161		result = acpi_power_get_context(handle, &resource);
162		if (result)
163			return result;
164
165		mutex_lock(&resource->resource_lock);
166
167		result = acpi_power_get_state(handle, &cur_state);
168
169		mutex_unlock(&resource->resource_lock);
170
171		if (result)
172			return result;
173
174		if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
175			break;
176	}
177
178	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
179			  cur_state ? "on" : "off"));
180
181	*state = cur_state;
182
183	return 0;
184}
185
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
186static int __acpi_power_on(struct acpi_power_resource *resource)
187{
188	acpi_status status = AE_OK;
189
190	status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
191	if (ACPI_FAILURE(status))
192		return -ENODEV;
193
194	/* Update the power resource's _device_ power state */
195	resource->device->power.state = ACPI_STATE_D0;
196
197	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
198			  resource->name));
199
200	return 0;
201}
202
203static int acpi_power_on(acpi_handle handle)
204{
205	int result = 0;
 
206	struct acpi_power_resource *resource = NULL;
 
207
208	result = acpi_power_get_context(handle, &resource);
209	if (result)
210		return result;
211
212	mutex_lock(&resource->resource_lock);
213
214	if (resource->ref_count++) {
215		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
216				  "Power resource [%s] already on",
217				  resource->name));
218	} else {
219		result = __acpi_power_on(resource);
220		if (result)
221			resource->ref_count--;
 
 
222	}
223
224	mutex_unlock(&resource->resource_lock);
225
 
 
 
 
 
 
 
 
 
 
 
 
 
226	return result;
227}
228
229static int acpi_power_off(acpi_handle handle)
230{
231	int result = 0;
232	acpi_status status = AE_OK;
233	struct acpi_power_resource *resource = NULL;
234
235	result = acpi_power_get_context(handle, &resource);
236	if (result)
237		return result;
238
239	mutex_lock(&resource->resource_lock);
240
241	if (!resource->ref_count) {
242		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
243				  "Power resource [%s] already off",
244				  resource->name));
245		goto unlock;
246	}
247
248	if (--resource->ref_count) {
249		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
250				  "Power resource [%s] still in use\n",
251				  resource->name));
252		goto unlock;
253	}
254
255	status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);
256	if (ACPI_FAILURE(status)) {
257		result = -ENODEV;
258	} else {
259		/* Update the power resource's _device_ power state */
260		resource->device->power.state = ACPI_STATE_D3;
261
262		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
263				  "Power resource [%s] turned off\n",
264				  resource->name));
265	}
266
267 unlock:
268	mutex_unlock(&resource->resource_lock);
269
270	return result;
271}
272
273static void __acpi_power_off_list(struct acpi_handle_list *list, int num_res)
274{
275	int i;
276
277	for (i = num_res - 1; i >= 0 ; i--)
278		acpi_power_off(list->handles[i]);
279}
280
281static void acpi_power_off_list(struct acpi_handle_list *list)
282{
283	__acpi_power_off_list(list, list->count);
284}
285
286static int acpi_power_on_list(struct acpi_handle_list *list)
287{
288	int result = 0;
289	int i;
290
291	for (i = 0; i < list->count; i++) {
292		result = acpi_power_on(list->handles[i]);
293		if (result) {
294			__acpi_power_off_list(list, i);
295			break;
296		}
297	}
298
299	return result;
300}
301
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
302/**
303 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
304 *                          ACPI 3.0) _PSW (Power State Wake)
305 * @dev: Device to handle.
306 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
307 * @sleep_state: Target sleep state of the system.
308 * @dev_state: Target power state of the device.
309 *
310 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
311 * State Wake) for the device, if present.  On failure reset the device's
312 * wakeup.flags.valid flag.
313 *
314 * RETURN VALUE:
315 * 0 if either _DSW or _PSW has been successfully executed
316 * 0 if neither _DSW nor _PSW has been found
317 * -ENODEV if the execution of either _DSW or _PSW has failed
318 */
319int acpi_device_sleep_wake(struct acpi_device *dev,
320                           int enable, int sleep_state, int dev_state)
321{
322	union acpi_object in_arg[3];
323	struct acpi_object_list arg_list = { 3, in_arg };
324	acpi_status status = AE_OK;
325
326	/*
327	 * Try to execute _DSW first.
328	 *
329	 * Three agruments are needed for the _DSW object:
330	 * Argument 0: enable/disable the wake capabilities
331	 * Argument 1: target system state
332	 * Argument 2: target device state
333	 * When _DSW object is called to disable the wake capabilities, maybe
334	 * the first argument is filled. The values of the other two agruments
335	 * are meaningless.
336	 */
337	in_arg[0].type = ACPI_TYPE_INTEGER;
338	in_arg[0].integer.value = enable;
339	in_arg[1].type = ACPI_TYPE_INTEGER;
340	in_arg[1].integer.value = sleep_state;
341	in_arg[2].type = ACPI_TYPE_INTEGER;
342	in_arg[2].integer.value = dev_state;
343	status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
344	if (ACPI_SUCCESS(status)) {
345		return 0;
346	} else if (status != AE_NOT_FOUND) {
347		printk(KERN_ERR PREFIX "_DSW execution failed\n");
348		dev->wakeup.flags.valid = 0;
349		return -ENODEV;
350	}
351
352	/* Execute _PSW */
353	arg_list.count = 1;
354	in_arg[0].integer.value = enable;
355	status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
356	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
357		printk(KERN_ERR PREFIX "_PSW execution failed\n");
358		dev->wakeup.flags.valid = 0;
359		return -ENODEV;
360	}
361
362	return 0;
363}
364
365/*
366 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
367 * 1. Power on the power resources required for the wakeup device 
368 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
369 *    State Wake) for the device, if present
370 */
371int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
372{
373	int i, err = 0;
374
375	if (!dev || !dev->wakeup.flags.valid)
376		return -EINVAL;
377
378	mutex_lock(&acpi_device_lock);
379
380	if (dev->wakeup.prepare_count++)
381		goto out;
382
383	/* Open power resource */
384	for (i = 0; i < dev->wakeup.resources.count; i++) {
385		int ret = acpi_power_on(dev->wakeup.resources.handles[i]);
386		if (ret) {
387			printk(KERN_ERR PREFIX "Transition power state\n");
388			dev->wakeup.flags.valid = 0;
389			err = -ENODEV;
390			goto err_out;
391		}
392	}
393
394	/*
395	 * Passing 3 as the third argument below means the device may be placed
396	 * in arbitrary power state afterwards.
397	 */
398	err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
399
400 err_out:
401	if (err)
402		dev->wakeup.prepare_count = 0;
403
404 out:
405	mutex_unlock(&acpi_device_lock);
406	return err;
407}
408
409/*
410 * Shutdown a wakeup device, counterpart of above method
411 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
412 *    State Wake) for the device, if present
413 * 2. Shutdown down the power resources
414 */
415int acpi_disable_wakeup_device_power(struct acpi_device *dev)
416{
417	int i, err = 0;
418
419	if (!dev || !dev->wakeup.flags.valid)
420		return -EINVAL;
421
422	mutex_lock(&acpi_device_lock);
423
424	if (--dev->wakeup.prepare_count > 0)
425		goto out;
426
427	/*
428	 * Executing the code below even if prepare_count is already zero when
429	 * the function is called may be useful, for example for initialisation.
430	 */
431	if (dev->wakeup.prepare_count < 0)
432		dev->wakeup.prepare_count = 0;
433
434	err = acpi_device_sleep_wake(dev, 0, 0, 0);
435	if (err)
436		goto out;
437
438	/* Close power resource */
439	for (i = 0; i < dev->wakeup.resources.count; i++) {
440		int ret = acpi_power_off(dev->wakeup.resources.handles[i]);
441		if (ret) {
442			printk(KERN_ERR PREFIX "Transition power state\n");
443			dev->wakeup.flags.valid = 0;
444			err = -ENODEV;
445			goto out;
446		}
447	}
448
449 out:
450	mutex_unlock(&acpi_device_lock);
451	return err;
452}
453
454/* --------------------------------------------------------------------------
455                             Device Power Management
456   -------------------------------------------------------------------------- */
457
458int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
459{
460	int result = 0;
461	struct acpi_handle_list *list = NULL;
462	int list_state = 0;
463	int i = 0;
464
465	if (!device || !state)
466		return -EINVAL;
467
468	/*
469	 * We know a device's inferred power state when all the resources
470	 * required for a given D-state are 'on'.
471	 */
472	for (i = ACPI_STATE_D0; i < ACPI_STATE_D3; i++) {
473		list = &device->power.states[i].resources;
474		if (list->count < 1)
475			continue;
476
477		result = acpi_power_get_list_state(list, &list_state);
478		if (result)
479			return result;
480
481		if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
482			*state = i;
483			return 0;
484		}
485	}
486
487	*state = ACPI_STATE_D3;
488	return 0;
489}
490
491int acpi_power_on_resources(struct acpi_device *device, int state)
492{
493	if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3)
494		return -EINVAL;
495
496	return acpi_power_on_list(&device->power.states[state].resources);
497}
498
499int acpi_power_transition(struct acpi_device *device, int state)
500{
501	int result;
502
503	if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
504		return -EINVAL;
505
506	if (device->power.state == state)
507		return 0;
508
509	if ((device->power.state < ACPI_STATE_D0)
510	    || (device->power.state > ACPI_STATE_D3))
511		return -ENODEV;
512
513	/* TBD: Resources must be ordered. */
514
515	/*
516	 * First we reference all power resources required in the target list
517	 * (e.g. so the device doesn't lose power while transitioning).  Then,
518	 * we dereference all power resources used in the current list.
519	 */
520	result = acpi_power_on_list(&device->power.states[state].resources);
521	if (!result)
 
 
 
522		acpi_power_off_list(
523			&device->power.states[device->power.state].resources);
524
525	/* We shouldn't change the state unless the above operations succeed. */
526	device->power.state = result ? ACPI_STATE_UNKNOWN : state;
527
528	return result;
529}
530
531/* --------------------------------------------------------------------------
532                                Driver Interface
533   -------------------------------------------------------------------------- */
534
535static int acpi_power_add(struct acpi_device *device)
536{
537	int result = 0, state;
538	acpi_status status = AE_OK;
539	struct acpi_power_resource *resource = NULL;
540	union acpi_object acpi_object;
541	struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
542
543
544	if (!device)
545		return -EINVAL;
546
547	resource = kzalloc(sizeof(struct acpi_power_resource), GFP_KERNEL);
548	if (!resource)
549		return -ENOMEM;
550
551	resource->device = device;
552	mutex_init(&resource->resource_lock);
 
553	strcpy(resource->name, device->pnp.bus_id);
554	strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
555	strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
556	device->driver_data = resource;
557
558	/* Evalute the object to get the system level and resource order. */
559	status = acpi_evaluate_object(device->handle, NULL, NULL, &buffer);
560	if (ACPI_FAILURE(status)) {
561		result = -ENODEV;
562		goto end;
563	}
564	resource->system_level = acpi_object.power_resource.system_level;
565	resource->order = acpi_object.power_resource.resource_order;
566
567	result = acpi_power_get_state(device->handle, &state);
568	if (result)
569		goto end;
570
571	switch (state) {
572	case ACPI_POWER_RESOURCE_STATE_ON:
573		device->power.state = ACPI_STATE_D0;
574		break;
575	case ACPI_POWER_RESOURCE_STATE_OFF:
576		device->power.state = ACPI_STATE_D3;
577		break;
578	default:
579		device->power.state = ACPI_STATE_UNKNOWN;
580		break;
581	}
582
583	printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
584	       acpi_device_bid(device), state ? "on" : "off");
585
586      end:
587	if (result)
588		kfree(resource);
589
590	return result;
591}
592
593static int acpi_power_remove(struct acpi_device *device, int type)
594{
595	struct acpi_power_resource *resource;
596
597	if (!device)
598		return -EINVAL;
599
600	resource = acpi_driver_data(device);
601	if (!resource)
602		return -EINVAL;
603
604	kfree(resource);
605
606	return 0;
607}
608
609static int acpi_power_resume(struct acpi_device *device)
610{
611	int result = 0, state;
612	struct acpi_power_resource *resource;
613
614	if (!device)
615		return -EINVAL;
616
617	resource = acpi_driver_data(device);
618	if (!resource)
619		return -EINVAL;
620
621	mutex_lock(&resource->resource_lock);
622
623	result = acpi_power_get_state(device->handle, &state);
624	if (result)
625		goto unlock;
626
627	if (state == ACPI_POWER_RESOURCE_STATE_OFF && resource->ref_count)
628		result = __acpi_power_on(resource);
629
630 unlock:
631	mutex_unlock(&resource->resource_lock);
632
633	return result;
634}
635
636int __init acpi_power_init(void)
637{
638	INIT_LIST_HEAD(&acpi_power_resource_list);
639	return acpi_bus_register_driver(&acpi_power_driver);
640}
v3.5.6
  1/*
  2 *  acpi_power.c - ACPI Bus Power Management ($Revision: 39 $)
  3 *
  4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
  5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
  6 *
  7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  8 *
  9 *  This program is free software; you can redistribute it and/or modify
 10 *  it under the terms of the GNU General Public License as published by
 11 *  the Free Software Foundation; either version 2 of the License, or (at
 12 *  your option) any later version.
 13 *
 14 *  This program is distributed in the hope that it will be useful, but
 15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 17 *  General Public License for more details.
 18 *
 19 *  You should have received a copy of the GNU General Public License along
 20 *  with this program; if not, write to the Free Software Foundation, Inc.,
 21 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 22 *
 23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 24 */
 25
 26/*
 27 * ACPI power-managed devices may be controlled in two ways:
 28 * 1. via "Device Specific (D-State) Control"
 29 * 2. via "Power Resource Control".
 30 * This module is used to manage devices relying on Power Resource Control.
 31 * 
 32 * An ACPI "power resource object" describes a software controllable power
 33 * plane, clock plane, or other resource used by a power managed device.
 34 * A device may rely on multiple power resources, and a power resource
 35 * may be shared by multiple devices.
 36 */
 37
 38#include <linux/kernel.h>
 39#include <linux/module.h>
 40#include <linux/init.h>
 41#include <linux/types.h>
 42#include <linux/slab.h>
 43#include <linux/pm_runtime.h>
 44#include <acpi/acpi_bus.h>
 45#include <acpi/acpi_drivers.h>
 46#include "sleep.h"
 47#include "internal.h"
 48
 49#define PREFIX "ACPI: "
 50
 51#define _COMPONENT			ACPI_POWER_COMPONENT
 52ACPI_MODULE_NAME("power");
 53#define ACPI_POWER_CLASS		"power_resource"
 54#define ACPI_POWER_DEVICE_NAME		"Power Resource"
 55#define ACPI_POWER_FILE_INFO		"info"
 56#define ACPI_POWER_FILE_STATUS		"state"
 57#define ACPI_POWER_RESOURCE_STATE_OFF	0x00
 58#define ACPI_POWER_RESOURCE_STATE_ON	0x01
 59#define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
 60
 61static int acpi_power_add(struct acpi_device *device);
 62static int acpi_power_remove(struct acpi_device *device, int type);
 63static int acpi_power_resume(struct acpi_device *device);
 64
 65static const struct acpi_device_id power_device_ids[] = {
 66	{ACPI_POWER_HID, 0},
 67	{"", 0},
 68};
 69MODULE_DEVICE_TABLE(acpi, power_device_ids);
 70
 71static struct acpi_driver acpi_power_driver = {
 72	.name = "power",
 73	.class = ACPI_POWER_CLASS,
 74	.ids = power_device_ids,
 75	.ops = {
 76		.add = acpi_power_add,
 77		.remove = acpi_power_remove,
 78		.resume = acpi_power_resume,
 79		},
 80};
 81
 82/*
 83 * A power managed device
 84 * A device may rely on multiple power resources.
 85 * */
 86struct acpi_power_managed_device {
 87	struct device *dev; /* The physical device */
 88	acpi_handle *handle;
 89};
 90
 91struct acpi_power_resource_device {
 92	struct acpi_power_managed_device *device;
 93	struct acpi_power_resource_device *next;
 94};
 95
 96struct acpi_power_resource {
 97	struct acpi_device * device;
 98	acpi_bus_id name;
 99	u32 system_level;
100	u32 order;
101	unsigned int ref_count;
102	struct mutex resource_lock;
103
104	/* List of devices relying on this power resource */
105	struct acpi_power_resource_device *devices;
106	struct mutex devices_lock;
107};
108
109static struct list_head acpi_power_resource_list;
110
111/* --------------------------------------------------------------------------
112                             Power Resource Management
113   -------------------------------------------------------------------------- */
114
115static int
116acpi_power_get_context(acpi_handle handle,
117		       struct acpi_power_resource **resource)
118{
119	int result = 0;
120	struct acpi_device *device = NULL;
121
122
123	if (!resource)
124		return -ENODEV;
125
126	result = acpi_bus_get_device(handle, &device);
127	if (result) {
128		printk(KERN_WARNING PREFIX "Getting context [%p]\n", handle);
129		return result;
130	}
131
132	*resource = acpi_driver_data(device);
133	if (!*resource)
134		return -ENODEV;
135
136	return 0;
137}
138
139static int acpi_power_get_state(acpi_handle handle, int *state)
140{
141	acpi_status status = AE_OK;
142	unsigned long long sta = 0;
143	char node_name[5];
144	struct acpi_buffer buffer = { sizeof(node_name), node_name };
145
146
147	if (!handle || !state)
148		return -EINVAL;
149
150	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
151	if (ACPI_FAILURE(status))
152		return -ENODEV;
153
154	*state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
155			      ACPI_POWER_RESOURCE_STATE_OFF;
156
157	acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
158
159	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
160			  node_name,
161				*state ? "on" : "off"));
162
163	return 0;
164}
165
166static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
167{
168	int cur_state;
169	int i = 0;
170
171	if (!list || !state)
172		return -EINVAL;
173
174	/* The state of the list is 'on' IFF all resources are 'on'. */
175
176	for (i = 0; i < list->count; i++) {
177		struct acpi_power_resource *resource;
178		acpi_handle handle = list->handles[i];
179		int result;
180
181		result = acpi_power_get_context(handle, &resource);
182		if (result)
183			return result;
184
185		mutex_lock(&resource->resource_lock);
186
187		result = acpi_power_get_state(handle, &cur_state);
188
189		mutex_unlock(&resource->resource_lock);
190
191		if (result)
192			return result;
193
194		if (cur_state != ACPI_POWER_RESOURCE_STATE_ON)
195			break;
196	}
197
198	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
199			  cur_state ? "on" : "off"));
200
201	*state = cur_state;
202
203	return 0;
204}
205
206/* Resume the device when all power resources in _PR0 are on */
207static void acpi_power_on_device(struct acpi_power_managed_device *device)
208{
209	struct acpi_device *acpi_dev;
210	acpi_handle handle = device->handle;
211	int state;
212
213	if (acpi_bus_get_device(handle, &acpi_dev))
214		return;
215
216	if(acpi_power_get_inferred_state(acpi_dev, &state))
217		return;
218
219	if (state == ACPI_STATE_D0 && pm_runtime_suspended(device->dev))
220		pm_request_resume(device->dev);
221}
222
223static int __acpi_power_on(struct acpi_power_resource *resource)
224{
225	acpi_status status = AE_OK;
226
227	status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
228	if (ACPI_FAILURE(status))
229		return -ENODEV;
230
231	/* Update the power resource's _device_ power state */
232	resource->device->power.state = ACPI_STATE_D0;
233
234	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Power resource [%s] turned on\n",
235			  resource->name));
236
237	return 0;
238}
239
240static int acpi_power_on(acpi_handle handle)
241{
242	int result = 0;
243	bool resume_device = false;
244	struct acpi_power_resource *resource = NULL;
245	struct acpi_power_resource_device *device_list;
246
247	result = acpi_power_get_context(handle, &resource);
248	if (result)
249		return result;
250
251	mutex_lock(&resource->resource_lock);
252
253	if (resource->ref_count++) {
254		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
255				  "Power resource [%s] already on",
256				  resource->name));
257	} else {
258		result = __acpi_power_on(resource);
259		if (result)
260			resource->ref_count--;
261		else
262			resume_device = true;
263	}
264
265	mutex_unlock(&resource->resource_lock);
266
267	if (!resume_device)
268		return result;
269
270	mutex_lock(&resource->devices_lock);
271
272	device_list = resource->devices;
273	while (device_list) {
274		acpi_power_on_device(device_list->device);
275		device_list = device_list->next;
276	}
277
278	mutex_unlock(&resource->devices_lock);
279
280	return result;
281}
282
283static int acpi_power_off(acpi_handle handle)
284{
285	int result = 0;
286	acpi_status status = AE_OK;
287	struct acpi_power_resource *resource = NULL;
288
289	result = acpi_power_get_context(handle, &resource);
290	if (result)
291		return result;
292
293	mutex_lock(&resource->resource_lock);
294
295	if (!resource->ref_count) {
296		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
297				  "Power resource [%s] already off",
298				  resource->name));
299		goto unlock;
300	}
301
302	if (--resource->ref_count) {
303		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
304				  "Power resource [%s] still in use\n",
305				  resource->name));
306		goto unlock;
307	}
308
309	status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);
310	if (ACPI_FAILURE(status)) {
311		result = -ENODEV;
312	} else {
313		/* Update the power resource's _device_ power state */
314		resource->device->power.state = ACPI_STATE_D3;
315
316		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
317				  "Power resource [%s] turned off\n",
318				  resource->name));
319	}
320
321 unlock:
322	mutex_unlock(&resource->resource_lock);
323
324	return result;
325}
326
327static void __acpi_power_off_list(struct acpi_handle_list *list, int num_res)
328{
329	int i;
330
331	for (i = num_res - 1; i >= 0 ; i--)
332		acpi_power_off(list->handles[i]);
333}
334
335static void acpi_power_off_list(struct acpi_handle_list *list)
336{
337	__acpi_power_off_list(list, list->count);
338}
339
340static int acpi_power_on_list(struct acpi_handle_list *list)
341{
342	int result = 0;
343	int i;
344
345	for (i = 0; i < list->count; i++) {
346		result = acpi_power_on(list->handles[i]);
347		if (result) {
348			__acpi_power_off_list(list, i);
349			break;
350		}
351	}
352
353	return result;
354}
355
356static void __acpi_power_resource_unregister_device(struct device *dev,
357		acpi_handle res_handle)
358{
359	struct acpi_power_resource *resource = NULL;
360	struct acpi_power_resource_device *prev, *curr;
361
362	if (acpi_power_get_context(res_handle, &resource))
363		return;
364
365	mutex_lock(&resource->devices_lock);
366	prev = NULL;
367	curr = resource->devices;
368	while (curr) {
369		if (curr->device->dev == dev) {
370			if (!prev)
371				resource->devices = curr->next;
372			else
373				prev->next = curr->next;
374
375			kfree(curr);
376			break;
377		}
378
379		prev = curr;
380		curr = curr->next;
381	}
382	mutex_unlock(&resource->devices_lock);
383}
384
385/* Unlink dev from all power resources in _PR0 */
386void acpi_power_resource_unregister_device(struct device *dev, acpi_handle handle)
387{
388	struct acpi_device *acpi_dev;
389	struct acpi_handle_list *list;
390	int i;
391
392	if (!dev || !handle)
393		return;
394
395	if (acpi_bus_get_device(handle, &acpi_dev))
396		return;
397
398	list = &acpi_dev->power.states[ACPI_STATE_D0].resources;
399
400	for (i = 0; i < list->count; i++)
401		__acpi_power_resource_unregister_device(dev,
402			list->handles[i]);
403}
404
405static int __acpi_power_resource_register_device(
406	struct acpi_power_managed_device *powered_device, acpi_handle handle)
407{
408	struct acpi_power_resource *resource = NULL;
409	struct acpi_power_resource_device *power_resource_device;
410	int result;
411
412	result = acpi_power_get_context(handle, &resource);
413	if (result)
414		return result;
415
416	power_resource_device = kzalloc(
417		sizeof(*power_resource_device), GFP_KERNEL);
418	if (!power_resource_device)
419		return -ENOMEM;
420
421	power_resource_device->device = powered_device;
422
423	mutex_lock(&resource->devices_lock);
424	power_resource_device->next = resource->devices;
425	resource->devices = power_resource_device;
426	mutex_unlock(&resource->devices_lock);
427
428	return 0;
429}
430
431/* Link dev to all power resources in _PR0 */
432int acpi_power_resource_register_device(struct device *dev, acpi_handle handle)
433{
434	struct acpi_device *acpi_dev;
435	struct acpi_handle_list *list;
436	struct acpi_power_managed_device *powered_device;
437	int i, ret;
438
439	if (!dev || !handle)
440		return -ENODEV;
441
442	ret = acpi_bus_get_device(handle, &acpi_dev);
443	if (ret)
444		goto no_power_resource;
445
446	if (!acpi_dev->power.flags.power_resources)
447		goto no_power_resource;
448
449	powered_device = kzalloc(sizeof(*powered_device), GFP_KERNEL);
450	if (!powered_device)
451		return -ENOMEM;
452
453	powered_device->dev = dev;
454	powered_device->handle = handle;
455
456	list = &acpi_dev->power.states[ACPI_STATE_D0].resources;
457
458	for (i = 0; i < list->count; i++) {
459		ret = __acpi_power_resource_register_device(powered_device,
460			list->handles[i]);
461
462		if (ret) {
463			acpi_power_resource_unregister_device(dev, handle);
464			break;
465		}
466	}
467
468	return ret;
469
470no_power_resource:
471	printk(KERN_DEBUG PREFIX "Invalid Power Resource to register!");
472	return -ENODEV;
473}
474
475/**
476 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
477 *                          ACPI 3.0) _PSW (Power State Wake)
478 * @dev: Device to handle.
479 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
480 * @sleep_state: Target sleep state of the system.
481 * @dev_state: Target power state of the device.
482 *
483 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
484 * State Wake) for the device, if present.  On failure reset the device's
485 * wakeup.flags.valid flag.
486 *
487 * RETURN VALUE:
488 * 0 if either _DSW or _PSW has been successfully executed
489 * 0 if neither _DSW nor _PSW has been found
490 * -ENODEV if the execution of either _DSW or _PSW has failed
491 */
492int acpi_device_sleep_wake(struct acpi_device *dev,
493                           int enable, int sleep_state, int dev_state)
494{
495	union acpi_object in_arg[3];
496	struct acpi_object_list arg_list = { 3, in_arg };
497	acpi_status status = AE_OK;
498
499	/*
500	 * Try to execute _DSW first.
501	 *
502	 * Three agruments are needed for the _DSW object:
503	 * Argument 0: enable/disable the wake capabilities
504	 * Argument 1: target system state
505	 * Argument 2: target device state
506	 * When _DSW object is called to disable the wake capabilities, maybe
507	 * the first argument is filled. The values of the other two agruments
508	 * are meaningless.
509	 */
510	in_arg[0].type = ACPI_TYPE_INTEGER;
511	in_arg[0].integer.value = enable;
512	in_arg[1].type = ACPI_TYPE_INTEGER;
513	in_arg[1].integer.value = sleep_state;
514	in_arg[2].type = ACPI_TYPE_INTEGER;
515	in_arg[2].integer.value = dev_state;
516	status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
517	if (ACPI_SUCCESS(status)) {
518		return 0;
519	} else if (status != AE_NOT_FOUND) {
520		printk(KERN_ERR PREFIX "_DSW execution failed\n");
521		dev->wakeup.flags.valid = 0;
522		return -ENODEV;
523	}
524
525	/* Execute _PSW */
526	arg_list.count = 1;
527	in_arg[0].integer.value = enable;
528	status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
529	if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
530		printk(KERN_ERR PREFIX "_PSW execution failed\n");
531		dev->wakeup.flags.valid = 0;
532		return -ENODEV;
533	}
534
535	return 0;
536}
537
538/*
539 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
540 * 1. Power on the power resources required for the wakeup device 
541 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
542 *    State Wake) for the device, if present
543 */
544int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
545{
546	int i, err = 0;
547
548	if (!dev || !dev->wakeup.flags.valid)
549		return -EINVAL;
550
551	mutex_lock(&acpi_device_lock);
552
553	if (dev->wakeup.prepare_count++)
554		goto out;
555
556	/* Open power resource */
557	for (i = 0; i < dev->wakeup.resources.count; i++) {
558		int ret = acpi_power_on(dev->wakeup.resources.handles[i]);
559		if (ret) {
560			printk(KERN_ERR PREFIX "Transition power state\n");
561			dev->wakeup.flags.valid = 0;
562			err = -ENODEV;
563			goto err_out;
564		}
565	}
566
567	/*
568	 * Passing 3 as the third argument below means the device may be placed
569	 * in arbitrary power state afterwards.
570	 */
571	err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
572
573 err_out:
574	if (err)
575		dev->wakeup.prepare_count = 0;
576
577 out:
578	mutex_unlock(&acpi_device_lock);
579	return err;
580}
581
582/*
583 * Shutdown a wakeup device, counterpart of above method
584 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
585 *    State Wake) for the device, if present
586 * 2. Shutdown down the power resources
587 */
588int acpi_disable_wakeup_device_power(struct acpi_device *dev)
589{
590	int i, err = 0;
591
592	if (!dev || !dev->wakeup.flags.valid)
593		return -EINVAL;
594
595	mutex_lock(&acpi_device_lock);
596
597	if (--dev->wakeup.prepare_count > 0)
598		goto out;
599
600	/*
601	 * Executing the code below even if prepare_count is already zero when
602	 * the function is called may be useful, for example for initialisation.
603	 */
604	if (dev->wakeup.prepare_count < 0)
605		dev->wakeup.prepare_count = 0;
606
607	err = acpi_device_sleep_wake(dev, 0, 0, 0);
608	if (err)
609		goto out;
610
611	/* Close power resource */
612	for (i = 0; i < dev->wakeup.resources.count; i++) {
613		int ret = acpi_power_off(dev->wakeup.resources.handles[i]);
614		if (ret) {
615			printk(KERN_ERR PREFIX "Transition power state\n");
616			dev->wakeup.flags.valid = 0;
617			err = -ENODEV;
618			goto out;
619		}
620	}
621
622 out:
623	mutex_unlock(&acpi_device_lock);
624	return err;
625}
626
627/* --------------------------------------------------------------------------
628                             Device Power Management
629   -------------------------------------------------------------------------- */
630
631int acpi_power_get_inferred_state(struct acpi_device *device, int *state)
632{
633	int result = 0;
634	struct acpi_handle_list *list = NULL;
635	int list_state = 0;
636	int i = 0;
637
638	if (!device || !state)
639		return -EINVAL;
640
641	/*
642	 * We know a device's inferred power state when all the resources
643	 * required for a given D-state are 'on'.
644	 */
645	for (i = ACPI_STATE_D0; i <= ACPI_STATE_D3_HOT; i++) {
646		list = &device->power.states[i].resources;
647		if (list->count < 1)
648			continue;
649
650		result = acpi_power_get_list_state(list, &list_state);
651		if (result)
652			return result;
653
654		if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
655			*state = i;
656			return 0;
657		}
658	}
659
660	*state = ACPI_STATE_D3;
661	return 0;
662}
663
664int acpi_power_on_resources(struct acpi_device *device, int state)
665{
666	if (!device || state < ACPI_STATE_D0 || state > ACPI_STATE_D3)
667		return -EINVAL;
668
669	return acpi_power_on_list(&device->power.states[state].resources);
670}
671
672int acpi_power_transition(struct acpi_device *device, int state)
673{
674	int result = 0;
675
676	if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3_COLD))
677		return -EINVAL;
678
679	if (device->power.state == state)
680		return 0;
681
682	if ((device->power.state < ACPI_STATE_D0)
683	    || (device->power.state > ACPI_STATE_D3_COLD))
684		return -ENODEV;
685
686	/* TBD: Resources must be ordered. */
687
688	/*
689	 * First we reference all power resources required in the target list
690	 * (e.g. so the device doesn't lose power while transitioning).  Then,
691	 * we dereference all power resources used in the current list.
692	 */
693	if (state < ACPI_STATE_D3_COLD)
694		result = acpi_power_on_list(
695			&device->power.states[state].resources);
696
697	if (!result && device->power.state < ACPI_STATE_D3_COLD)
698		acpi_power_off_list(
699			&device->power.states[device->power.state].resources);
700
701	/* We shouldn't change the state unless the above operations succeed. */
702	device->power.state = result ? ACPI_STATE_UNKNOWN : state;
703
704	return result;
705}
706
707/* --------------------------------------------------------------------------
708                                Driver Interface
709   -------------------------------------------------------------------------- */
710
711static int acpi_power_add(struct acpi_device *device)
712{
713	int result = 0, state;
714	acpi_status status = AE_OK;
715	struct acpi_power_resource *resource = NULL;
716	union acpi_object acpi_object;
717	struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
718
719
720	if (!device)
721		return -EINVAL;
722
723	resource = kzalloc(sizeof(struct acpi_power_resource), GFP_KERNEL);
724	if (!resource)
725		return -ENOMEM;
726
727	resource->device = device;
728	mutex_init(&resource->resource_lock);
729	mutex_init(&resource->devices_lock);
730	strcpy(resource->name, device->pnp.bus_id);
731	strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
732	strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
733	device->driver_data = resource;
734
735	/* Evalute the object to get the system level and resource order. */
736	status = acpi_evaluate_object(device->handle, NULL, NULL, &buffer);
737	if (ACPI_FAILURE(status)) {
738		result = -ENODEV;
739		goto end;
740	}
741	resource->system_level = acpi_object.power_resource.system_level;
742	resource->order = acpi_object.power_resource.resource_order;
743
744	result = acpi_power_get_state(device->handle, &state);
745	if (result)
746		goto end;
747
748	switch (state) {
749	case ACPI_POWER_RESOURCE_STATE_ON:
750		device->power.state = ACPI_STATE_D0;
751		break;
752	case ACPI_POWER_RESOURCE_STATE_OFF:
753		device->power.state = ACPI_STATE_D3;
754		break;
755	default:
756		device->power.state = ACPI_STATE_UNKNOWN;
757		break;
758	}
759
760	printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
761	       acpi_device_bid(device), state ? "on" : "off");
762
763      end:
764	if (result)
765		kfree(resource);
766
767	return result;
768}
769
770static int acpi_power_remove(struct acpi_device *device, int type)
771{
772	struct acpi_power_resource *resource;
773
774	if (!device)
775		return -EINVAL;
776
777	resource = acpi_driver_data(device);
778	if (!resource)
779		return -EINVAL;
780
781	kfree(resource);
782
783	return 0;
784}
785
786static int acpi_power_resume(struct acpi_device *device)
787{
788	int result = 0, state;
789	struct acpi_power_resource *resource;
790
791	if (!device)
792		return -EINVAL;
793
794	resource = acpi_driver_data(device);
795	if (!resource)
796		return -EINVAL;
797
798	mutex_lock(&resource->resource_lock);
799
800	result = acpi_power_get_state(device->handle, &state);
801	if (result)
802		goto unlock;
803
804	if (state == ACPI_POWER_RESOURCE_STATE_OFF && resource->ref_count)
805		result = __acpi_power_on(resource);
806
807 unlock:
808	mutex_unlock(&resource->resource_lock);
809
810	return result;
811}
812
813int __init acpi_power_init(void)
814{
815	INIT_LIST_HEAD(&acpi_power_resource_list);
816	return acpi_bus_register_driver(&acpi_power_driver);
817}