ALSA: hda - Terradici HDA controllers does not support 64-bit mode
[linux-2.6/mini2440.git] / drivers / acpi / power.c
blobd74365d4a6e7d03f781954663301c50d30ac77da
1 /*
2 * acpi_power.c - ACPI Bus Power Management ($Revision: 39 $)
4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
38 #include <linux/kernel.h>
39 #include <linux/module.h>
40 #include <linux/init.h>
41 #include <linux/types.h>
42 #include <linux/proc_fs.h>
43 #include <linux/seq_file.h>
44 #include <acpi/acpi_bus.h>
45 #include <acpi/acpi_drivers.h>
47 #define _COMPONENT ACPI_POWER_COMPONENT
48 ACPI_MODULE_NAME("power");
49 #define ACPI_POWER_CLASS "power_resource"
50 #define ACPI_POWER_DEVICE_NAME "Power Resource"
51 #define ACPI_POWER_FILE_INFO "info"
52 #define ACPI_POWER_FILE_STATUS "state"
53 #define ACPI_POWER_RESOURCE_STATE_OFF 0x00
54 #define ACPI_POWER_RESOURCE_STATE_ON 0x01
55 #define ACPI_POWER_RESOURCE_STATE_UNKNOWN 0xFF
57 int acpi_power_nocheck;
58 module_param_named(power_nocheck, acpi_power_nocheck, bool, 000);
60 static int acpi_power_add(struct acpi_device *device);
61 static int acpi_power_remove(struct acpi_device *device, int type);
62 static int acpi_power_resume(struct acpi_device *device);
63 static int acpi_power_open_fs(struct inode *inode, struct file *file);
65 static struct acpi_device_id power_device_ids[] = {
66 {ACPI_POWER_HID, 0},
67 {"", 0},
69 MODULE_DEVICE_TABLE(acpi, power_device_ids);
71 static 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,
82 struct acpi_power_reference {
83 struct list_head node;
84 struct acpi_device *device;
87 struct acpi_power_resource {
88 struct acpi_device * device;
89 acpi_bus_id name;
90 u32 system_level;
91 u32 order;
92 struct mutex resource_lock;
93 struct list_head reference;
96 static struct list_head acpi_power_resource_list;
98 static const struct file_operations acpi_power_fops = {
99 .owner = THIS_MODULE,
100 .open = acpi_power_open_fs,
101 .read = seq_read,
102 .llseek = seq_lseek,
103 .release = single_release,
106 /* --------------------------------------------------------------------------
107 Power Resource Management
108 -------------------------------------------------------------------------- */
110 static int
111 acpi_power_get_context(acpi_handle handle,
112 struct acpi_power_resource **resource)
114 int result = 0;
115 struct acpi_device *device = NULL;
118 if (!resource)
119 return -ENODEV;
121 result = acpi_bus_get_device(handle, &device);
122 if (result) {
123 printk(KERN_WARNING PREFIX "Getting context [%p]\n", handle);
124 return result;
127 *resource = acpi_driver_data(device);
128 if (!*resource)
129 return -ENODEV;
131 return 0;
134 static int acpi_power_get_state(acpi_handle handle, int *state)
136 acpi_status status = AE_OK;
137 unsigned long long sta = 0;
138 char node_name[5];
139 struct acpi_buffer buffer = { sizeof(node_name), node_name };
142 if (!handle || !state)
143 return -EINVAL;
145 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
146 if (ACPI_FAILURE(status))
147 return -ENODEV;
149 *state = (sta & 0x01)?ACPI_POWER_RESOURCE_STATE_ON:
150 ACPI_POWER_RESOURCE_STATE_OFF;
152 acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer);
154 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
155 node_name,
156 *state ? "on" : "off"));
158 return 0;
161 static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
163 int result = 0, state1;
164 u32 i = 0;
167 if (!list || !state)
168 return -EINVAL;
170 /* The state of the list is 'on' IFF all resources are 'on'. */
171 /* */
173 for (i = 0; i < list->count; i++) {
175 * The state of the power resource can be obtained by
176 * using the ACPI handle. In such case it is unnecessary to
177 * get the Power resource first and then get its state again.
179 result = acpi_power_get_state(list->handles[i], &state1);
180 if (result)
181 return result;
183 *state = state1;
185 if (*state != ACPI_POWER_RESOURCE_STATE_ON)
186 break;
189 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
190 *state ? "on" : "off"));
192 return result;
195 static int acpi_power_on(acpi_handle handle, struct acpi_device *dev)
197 int result = 0;
198 int found = 0;
199 acpi_status status = AE_OK;
200 struct acpi_power_resource *resource = NULL;
201 struct list_head *node, *next;
202 struct acpi_power_reference *ref;
205 result = acpi_power_get_context(handle, &resource);
206 if (result)
207 return result;
209 mutex_lock(&resource->resource_lock);
210 list_for_each_safe(node, next, &resource->reference) {
211 ref = container_of(node, struct acpi_power_reference, node);
212 if (dev->handle == ref->device->handle) {
213 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] already referenced by resource [%s]\n",
214 dev->pnp.bus_id, resource->name));
215 found = 1;
216 break;
220 if (!found) {
221 ref = kmalloc(sizeof (struct acpi_power_reference),
222 irqs_disabled() ? GFP_ATOMIC : GFP_KERNEL);
223 if (!ref) {
224 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "kmalloc() failed\n"));
225 mutex_unlock(&resource->resource_lock);
226 return -ENOMEM;
228 list_add_tail(&ref->node, &resource->reference);
229 ref->device = dev;
230 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] added to resource [%s] references\n",
231 dev->pnp.bus_id, resource->name));
233 mutex_unlock(&resource->resource_lock);
235 status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
236 if (ACPI_FAILURE(status))
237 return -ENODEV;
239 /* Update the power resource's _device_ power state */
240 resource->device->power.state = ACPI_STATE_D0;
242 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned on\n",
243 resource->name));
244 return 0;
247 static int acpi_power_off_device(acpi_handle handle, struct acpi_device *dev)
249 int result = 0;
250 acpi_status status = AE_OK;
251 struct acpi_power_resource *resource = NULL;
252 struct list_head *node, *next;
253 struct acpi_power_reference *ref;
256 result = acpi_power_get_context(handle, &resource);
257 if (result)
258 return result;
260 mutex_lock(&resource->resource_lock);
261 list_for_each_safe(node, next, &resource->reference) {
262 ref = container_of(node, struct acpi_power_reference, node);
263 if (dev->handle == ref->device->handle) {
264 list_del(&ref->node);
265 kfree(ref);
266 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Device [%s] removed from resource [%s] references\n",
267 dev->pnp.bus_id, resource->name));
268 break;
272 if (!list_empty(&resource->reference)) {
273 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Cannot turn resource [%s] off - resource is in use\n",
274 resource->name));
275 mutex_unlock(&resource->resource_lock);
276 return 0;
278 mutex_unlock(&resource->resource_lock);
280 status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);
281 if (ACPI_FAILURE(status))
282 return -ENODEV;
284 /* Update the power resource's _device_ power state */
285 resource->device->power.state = ACPI_STATE_D3;
287 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned off\n",
288 resource->name));
290 return 0;
294 * acpi_device_sleep_wake - execute _DSW (Device Sleep Wake) or (deprecated in
295 * ACPI 3.0) _PSW (Power State Wake)
296 * @dev: Device to handle.
297 * @enable: 0 - disable, 1 - enable the wake capabilities of the device.
298 * @sleep_state: Target sleep state of the system.
299 * @dev_state: Target power state of the device.
301 * Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
302 * State Wake) for the device, if present. On failure reset the device's
303 * wakeup.flags.valid flag.
305 * RETURN VALUE:
306 * 0 if either _DSW or _PSW has been successfully executed
307 * 0 if neither _DSW nor _PSW has been found
308 * -ENODEV if the execution of either _DSW or _PSW has failed
310 int acpi_device_sleep_wake(struct acpi_device *dev,
311 int enable, int sleep_state, int dev_state)
313 union acpi_object in_arg[3];
314 struct acpi_object_list arg_list = { 3, in_arg };
315 acpi_status status = AE_OK;
318 * Try to execute _DSW first.
320 * Three agruments are needed for the _DSW object:
321 * Argument 0: enable/disable the wake capabilities
322 * Argument 1: target system state
323 * Argument 2: target device state
324 * When _DSW object is called to disable the wake capabilities, maybe
325 * the first argument is filled. The values of the other two agruments
326 * are meaningless.
328 in_arg[0].type = ACPI_TYPE_INTEGER;
329 in_arg[0].integer.value = enable;
330 in_arg[1].type = ACPI_TYPE_INTEGER;
331 in_arg[1].integer.value = sleep_state;
332 in_arg[2].type = ACPI_TYPE_INTEGER;
333 in_arg[2].integer.value = dev_state;
334 status = acpi_evaluate_object(dev->handle, "_DSW", &arg_list, NULL);
335 if (ACPI_SUCCESS(status)) {
336 return 0;
337 } else if (status != AE_NOT_FOUND) {
338 printk(KERN_ERR PREFIX "_DSW execution failed\n");
339 dev->wakeup.flags.valid = 0;
340 return -ENODEV;
343 /* Execute _PSW */
344 arg_list.count = 1;
345 in_arg[0].integer.value = enable;
346 status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
347 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
348 printk(KERN_ERR PREFIX "_PSW execution failed\n");
349 dev->wakeup.flags.valid = 0;
350 return -ENODEV;
353 return 0;
357 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
358 * 1. Power on the power resources required for the wakeup device
359 * 2. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
360 * State Wake) for the device, if present
362 int acpi_enable_wakeup_device_power(struct acpi_device *dev, int sleep_state)
364 int i, err;
366 if (!dev || !dev->wakeup.flags.valid)
367 return -EINVAL;
370 * Do not execute the code below twice in a row without calling
371 * acpi_disable_wakeup_device_power() in between for the same device
373 if (dev->wakeup.flags.prepared)
374 return 0;
376 /* Open power resource */
377 for (i = 0; i < dev->wakeup.resources.count; i++) {
378 int ret = acpi_power_on(dev->wakeup.resources.handles[i], dev);
379 if (ret) {
380 printk(KERN_ERR PREFIX "Transition power state\n");
381 dev->wakeup.flags.valid = 0;
382 return -ENODEV;
387 * Passing 3 as the third argument below means the device may be placed
388 * in arbitrary power state afterwards.
390 err = acpi_device_sleep_wake(dev, 1, sleep_state, 3);
391 if (!err)
392 dev->wakeup.flags.prepared = 1;
394 return err;
398 * Shutdown a wakeup device, counterpart of above method
399 * 1. Execute _DSW (Device Sleep Wake) or (deprecated in ACPI 3.0) _PSW (Power
400 * State Wake) for the device, if present
401 * 2. Shutdown down the power resources
403 int acpi_disable_wakeup_device_power(struct acpi_device *dev)
405 int i, ret;
407 if (!dev || !dev->wakeup.flags.valid)
408 return -EINVAL;
411 * Do not execute the code below twice in a row without calling
412 * acpi_enable_wakeup_device_power() in between for the same device
414 if (!dev->wakeup.flags.prepared)
415 return 0;
417 dev->wakeup.flags.prepared = 0;
419 ret = acpi_device_sleep_wake(dev, 0, 0, 0);
420 if (ret)
421 return ret;
423 /* Close power resource */
424 for (i = 0; i < dev->wakeup.resources.count; i++) {
425 ret = acpi_power_off_device(dev->wakeup.resources.handles[i], dev);
426 if (ret) {
427 printk(KERN_ERR PREFIX "Transition power state\n");
428 dev->wakeup.flags.valid = 0;
429 return -ENODEV;
433 return ret;
436 /* --------------------------------------------------------------------------
437 Device Power Management
438 -------------------------------------------------------------------------- */
440 int acpi_power_get_inferred_state(struct acpi_device *device)
442 int result = 0;
443 struct acpi_handle_list *list = NULL;
444 int list_state = 0;
445 int i = 0;
448 if (!device)
449 return -EINVAL;
451 device->power.state = ACPI_STATE_UNKNOWN;
454 * We know a device's inferred power state when all the resources
455 * required for a given D-state are 'on'.
457 for (i = ACPI_STATE_D0; i < ACPI_STATE_D3; i++) {
458 list = &device->power.states[i].resources;
459 if (list->count < 1)
460 continue;
462 result = acpi_power_get_list_state(list, &list_state);
463 if (result)
464 return result;
466 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
467 device->power.state = i;
468 return 0;
472 device->power.state = ACPI_STATE_D3;
474 return 0;
477 int acpi_power_transition(struct acpi_device *device, int state)
479 int result = 0;
480 struct acpi_handle_list *cl = NULL; /* Current Resources */
481 struct acpi_handle_list *tl = NULL; /* Target Resources */
482 int i = 0;
485 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
486 return -EINVAL;
488 if ((device->power.state < ACPI_STATE_D0)
489 || (device->power.state > ACPI_STATE_D3))
490 return -ENODEV;
492 cl = &device->power.states[device->power.state].resources;
493 tl = &device->power.states[state].resources;
495 /* TBD: Resources must be ordered. */
498 * First we reference all power resources required in the target list
499 * (e.g. so the device doesn't lose power while transitioning).
501 for (i = 0; i < tl->count; i++) {
502 result = acpi_power_on(tl->handles[i], device);
503 if (result)
504 goto end;
507 if (device->power.state == state) {
508 goto end;
512 * Then we dereference all power resources used in the current list.
514 for (i = 0; i < cl->count; i++) {
515 result = acpi_power_off_device(cl->handles[i], device);
516 if (result)
517 goto end;
520 end:
521 if (result)
522 device->power.state = ACPI_STATE_UNKNOWN;
523 else {
524 /* We shouldn't change the state till all above operations succeed */
525 device->power.state = state;
528 return result;
531 /* --------------------------------------------------------------------------
532 FS Interface (/proc)
533 -------------------------------------------------------------------------- */
535 static struct proc_dir_entry *acpi_power_dir;
537 static int acpi_power_seq_show(struct seq_file *seq, void *offset)
539 int count = 0;
540 int result = 0, state;
541 struct acpi_power_resource *resource = NULL;
542 struct list_head *node, *next;
543 struct acpi_power_reference *ref;
546 resource = seq->private;
548 if (!resource)
549 goto end;
551 result = acpi_power_get_state(resource->device->handle, &state);
552 if (result)
553 goto end;
555 seq_puts(seq, "state: ");
556 switch (state) {
557 case ACPI_POWER_RESOURCE_STATE_ON:
558 seq_puts(seq, "on\n");
559 break;
560 case ACPI_POWER_RESOURCE_STATE_OFF:
561 seq_puts(seq, "off\n");
562 break;
563 default:
564 seq_puts(seq, "unknown\n");
565 break;
568 mutex_lock(&resource->resource_lock);
569 list_for_each_safe(node, next, &resource->reference) {
570 ref = container_of(node, struct acpi_power_reference, node);
571 count++;
573 mutex_unlock(&resource->resource_lock);
575 seq_printf(seq, "system level: S%d\n"
576 "order: %d\n"
577 "reference count: %d\n",
578 resource->system_level,
579 resource->order, count);
581 end:
582 return 0;
585 static int acpi_power_open_fs(struct inode *inode, struct file *file)
587 return single_open(file, acpi_power_seq_show, PDE(inode)->data);
590 static int acpi_power_add_fs(struct acpi_device *device)
592 struct proc_dir_entry *entry = NULL;
595 if (!device)
596 return -EINVAL;
598 if (!acpi_device_dir(device)) {
599 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
600 acpi_power_dir);
601 if (!acpi_device_dir(device))
602 return -ENODEV;
605 /* 'status' [R] */
606 entry = proc_create_data(ACPI_POWER_FILE_STATUS,
607 S_IRUGO, acpi_device_dir(device),
608 &acpi_power_fops, acpi_driver_data(device));
609 if (!entry)
610 return -EIO;
611 return 0;
614 static int acpi_power_remove_fs(struct acpi_device *device)
617 if (acpi_device_dir(device)) {
618 remove_proc_entry(ACPI_POWER_FILE_STATUS,
619 acpi_device_dir(device));
620 remove_proc_entry(acpi_device_bid(device), acpi_power_dir);
621 acpi_device_dir(device) = NULL;
624 return 0;
627 /* --------------------------------------------------------------------------
628 Driver Interface
629 -------------------------------------------------------------------------- */
631 static int acpi_power_add(struct acpi_device *device)
633 int result = 0, state;
634 acpi_status status = AE_OK;
635 struct acpi_power_resource *resource = NULL;
636 union acpi_object acpi_object;
637 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
640 if (!device)
641 return -EINVAL;
643 resource = kzalloc(sizeof(struct acpi_power_resource), GFP_KERNEL);
644 if (!resource)
645 return -ENOMEM;
647 resource->device = device;
648 mutex_init(&resource->resource_lock);
649 INIT_LIST_HEAD(&resource->reference);
650 strcpy(resource->name, device->pnp.bus_id);
651 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
652 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
653 device->driver_data = resource;
655 /* Evalute the object to get the system level and resource order. */
656 status = acpi_evaluate_object(device->handle, NULL, NULL, &buffer);
657 if (ACPI_FAILURE(status)) {
658 result = -ENODEV;
659 goto end;
661 resource->system_level = acpi_object.power_resource.system_level;
662 resource->order = acpi_object.power_resource.resource_order;
664 result = acpi_power_get_state(device->handle, &state);
665 if (result)
666 goto end;
668 switch (state) {
669 case ACPI_POWER_RESOURCE_STATE_ON:
670 device->power.state = ACPI_STATE_D0;
671 break;
672 case ACPI_POWER_RESOURCE_STATE_OFF:
673 device->power.state = ACPI_STATE_D3;
674 break;
675 default:
676 device->power.state = ACPI_STATE_UNKNOWN;
677 break;
680 result = acpi_power_add_fs(device);
681 if (result)
682 goto end;
684 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
685 acpi_device_bid(device), state ? "on" : "off");
687 end:
688 if (result)
689 kfree(resource);
691 return result;
694 static int acpi_power_remove(struct acpi_device *device, int type)
696 struct acpi_power_resource *resource = NULL;
697 struct list_head *node, *next;
700 if (!device || !acpi_driver_data(device))
701 return -EINVAL;
703 resource = acpi_driver_data(device);
705 acpi_power_remove_fs(device);
707 mutex_lock(&resource->resource_lock);
708 list_for_each_safe(node, next, &resource->reference) {
709 struct acpi_power_reference *ref = container_of(node, struct acpi_power_reference, node);
710 list_del(&ref->node);
711 kfree(ref);
713 mutex_unlock(&resource->resource_lock);
715 kfree(resource);
717 return 0;
720 static int acpi_power_resume(struct acpi_device *device)
722 int result = 0, state;
723 struct acpi_power_resource *resource = NULL;
724 struct acpi_power_reference *ref;
726 if (!device || !acpi_driver_data(device))
727 return -EINVAL;
729 resource = acpi_driver_data(device);
731 result = acpi_power_get_state(device->handle, &state);
732 if (result)
733 return result;
735 mutex_lock(&resource->resource_lock);
736 if (state == ACPI_POWER_RESOURCE_STATE_OFF &&
737 !list_empty(&resource->reference)) {
738 ref = container_of(resource->reference.next, struct acpi_power_reference, node);
739 mutex_unlock(&resource->resource_lock);
740 result = acpi_power_on(device->handle, ref->device);
741 return result;
744 mutex_unlock(&resource->resource_lock);
745 return 0;
748 int __init acpi_power_init(void)
750 int result = 0;
752 INIT_LIST_HEAD(&acpi_power_resource_list);
754 acpi_power_dir = proc_mkdir(ACPI_POWER_CLASS, acpi_root_dir);
755 if (!acpi_power_dir)
756 return -ENODEV;
758 result = acpi_bus_register_driver(&acpi_power_driver);
759 if (result < 0) {
760 remove_proc_entry(ACPI_POWER_CLASS, acpi_root_dir);
761 return -ENODEV;
764 return 0;