ia64/linux-2.6.18-xen.hg

view drivers/acpi/power.c @ 912:dd42cdb0ab89

[IA64] Build blktap2 driver by default in x86 builds.

add CONFIG_XEN_BLKDEV_TAP2=y to buildconfigs/linux-defconfig_xen_ia64.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Mon Jun 29 12:09:16 2009 +0900 (2009-06-29)
parents 831230e53067
children
line source
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 */
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 */
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("acpi_power")
49 #define ACPI_POWER_COMPONENT 0x00800000
50 #define ACPI_POWER_CLASS "power_resource"
51 #define ACPI_POWER_DRIVER_NAME "ACPI Power Resource Driver"
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 static int acpi_power_add(struct acpi_device *device);
59 static int acpi_power_remove(struct acpi_device *device, int type);
60 static int acpi_power_open_fs(struct inode *inode, struct file *file);
62 static struct acpi_driver acpi_power_driver = {
63 .name = ACPI_POWER_DRIVER_NAME,
64 .class = ACPI_POWER_CLASS,
65 .ids = ACPI_POWER_HID,
66 .ops = {
67 .add = acpi_power_add,
68 .remove = acpi_power_remove,
69 },
70 };
72 struct acpi_power_resource {
73 struct acpi_device * device;
74 acpi_bus_id name;
75 u32 system_level;
76 u32 order;
77 int state;
78 int references;
79 };
81 static struct list_head acpi_power_resource_list;
83 static const struct file_operations acpi_power_fops = {
84 .open = acpi_power_open_fs,
85 .read = seq_read,
86 .llseek = seq_lseek,
87 .release = single_release,
88 };
90 /* --------------------------------------------------------------------------
91 Power Resource Management
92 -------------------------------------------------------------------------- */
94 static int
95 acpi_power_get_context(acpi_handle handle,
96 struct acpi_power_resource **resource)
97 {
98 int result = 0;
99 struct acpi_device *device = NULL;
102 if (!resource)
103 return -ENODEV;
105 result = acpi_bus_get_device(handle, &device);
106 if (result) {
107 printk(KERN_WARNING PREFIX "Getting context [%p]\n", handle);
108 return result;
109 }
111 *resource = (struct acpi_power_resource *)acpi_driver_data(device);
112 if (!resource)
113 return -ENODEV;
115 return 0;
116 }
118 static int acpi_power_get_state(struct acpi_power_resource *resource)
119 {
120 acpi_status status = AE_OK;
121 unsigned long sta = 0;
124 if (!resource)
125 return -EINVAL;
127 status = acpi_evaluate_integer(resource->device->handle, "_STA", NULL, &sta);
128 if (ACPI_FAILURE(status))
129 return -ENODEV;
131 if (sta & 0x01)
132 resource->state = ACPI_POWER_RESOURCE_STATE_ON;
133 else
134 resource->state = ACPI_POWER_RESOURCE_STATE_OFF;
136 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] is %s\n",
137 resource->name, resource->state ? "on" : "off"));
139 return 0;
140 }
142 static int acpi_power_get_list_state(struct acpi_handle_list *list, int *state)
143 {
144 int result = 0;
145 struct acpi_power_resource *resource = NULL;
146 u32 i = 0;
149 if (!list || !state)
150 return -EINVAL;
152 /* The state of the list is 'on' IFF all resources are 'on'. */
154 for (i = 0; i < list->count; i++) {
155 result = acpi_power_get_context(list->handles[i], &resource);
156 if (result)
157 return result;
158 result = acpi_power_get_state(resource);
159 if (result)
160 return result;
162 *state = resource->state;
164 if (*state != ACPI_POWER_RESOURCE_STATE_ON)
165 break;
166 }
168 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource list is %s\n",
169 *state ? "on" : "off"));
171 return result;
172 }
174 static int acpi_power_on(acpi_handle handle)
175 {
176 int result = 0;
177 acpi_status status = AE_OK;
178 struct acpi_device *device = NULL;
179 struct acpi_power_resource *resource = NULL;
182 result = acpi_power_get_context(handle, &resource);
183 if (result)
184 return result;
186 resource->references++;
188 if ((resource->references > 1)
189 || (resource->state == ACPI_POWER_RESOURCE_STATE_ON)) {
190 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already on\n",
191 resource->name));
192 return 0;
193 }
195 status = acpi_evaluate_object(resource->device->handle, "_ON", NULL, NULL);
196 if (ACPI_FAILURE(status))
197 return -ENODEV;
199 result = acpi_power_get_state(resource);
200 if (result)
201 return result;
202 if (resource->state != ACPI_POWER_RESOURCE_STATE_ON)
203 return -ENOEXEC;
205 /* Update the power resource's _device_ power state */
206 device = resource->device;
207 resource->device->power.state = ACPI_STATE_D0;
209 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned on\n",
210 resource->name));
212 return 0;
213 }
215 static int acpi_power_off_device(acpi_handle handle)
216 {
217 int result = 0;
218 acpi_status status = AE_OK;
219 struct acpi_device *device = NULL;
220 struct acpi_power_resource *resource = NULL;
223 result = acpi_power_get_context(handle, &resource);
224 if (result)
225 return result;
227 if (resource->references)
228 resource->references--;
230 if (resource->references) {
231 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
232 "Resource [%s] is still in use, dereferencing\n",
233 device->pnp.bus_id));
234 return 0;
235 }
237 if (resource->state == ACPI_POWER_RESOURCE_STATE_OFF) {
238 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] already off\n",
239 device->pnp.bus_id));
240 return 0;
241 }
243 status = acpi_evaluate_object(resource->device->handle, "_OFF", NULL, NULL);
244 if (ACPI_FAILURE(status))
245 return -ENODEV;
247 result = acpi_power_get_state(resource);
248 if (result)
249 return result;
250 if (resource->state != ACPI_POWER_RESOURCE_STATE_OFF)
251 return -ENOEXEC;
253 /* Update the power resource's _device_ power state */
254 device = resource->device;
255 device->power.state = ACPI_STATE_D3;
257 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Resource [%s] turned off\n",
258 resource->name));
260 return 0;
261 }
263 /*
264 * Prepare a wakeup device, two steps (Ref ACPI 2.0:P229):
265 * 1. Power on the power resources required for the wakeup device
266 * 2. Enable _PSW (power state wake) for the device if present
267 */
268 int acpi_enable_wakeup_device_power(struct acpi_device *dev)
269 {
270 union acpi_object arg = { ACPI_TYPE_INTEGER };
271 struct acpi_object_list arg_list = { 1, &arg };
272 acpi_status status = AE_OK;
273 int i;
274 int ret = 0;
276 if (!dev || !dev->wakeup.flags.valid)
277 return -1;
279 arg.integer.value = 1;
280 /* Open power resource */
281 for (i = 0; i < dev->wakeup.resources.count; i++) {
282 ret = acpi_power_on(dev->wakeup.resources.handles[i]);
283 if (ret) {
284 printk(KERN_ERR PREFIX "Transition power state\n");
285 dev->wakeup.flags.valid = 0;
286 return -1;
287 }
288 }
290 /* Execute PSW */
291 status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
292 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
293 printk(KERN_ERR PREFIX "Evaluate _PSW\n");
294 dev->wakeup.flags.valid = 0;
295 ret = -1;
296 }
298 return ret;
299 }
301 /*
302 * Shutdown a wakeup device, counterpart of above method
303 * 1. Disable _PSW (power state wake)
304 * 2. Shutdown down the power resources
305 */
306 int acpi_disable_wakeup_device_power(struct acpi_device *dev)
307 {
308 union acpi_object arg = { ACPI_TYPE_INTEGER };
309 struct acpi_object_list arg_list = { 1, &arg };
310 acpi_status status = AE_OK;
311 int i;
312 int ret = 0;
315 if (!dev || !dev->wakeup.flags.valid)
316 return -1;
318 arg.integer.value = 0;
319 /* Execute PSW */
320 status = acpi_evaluate_object(dev->handle, "_PSW", &arg_list, NULL);
321 if (ACPI_FAILURE(status) && (status != AE_NOT_FOUND)) {
322 printk(KERN_ERR PREFIX "Evaluate _PSW\n");
323 dev->wakeup.flags.valid = 0;
324 return -1;
325 }
327 /* Close power resource */
328 for (i = 0; i < dev->wakeup.resources.count; i++) {
329 ret = acpi_power_off_device(dev->wakeup.resources.handles[i]);
330 if (ret) {
331 printk(KERN_ERR PREFIX "Transition power state\n");
332 dev->wakeup.flags.valid = 0;
333 return -1;
334 }
335 }
337 return ret;
338 }
340 /* --------------------------------------------------------------------------
341 Device Power Management
342 -------------------------------------------------------------------------- */
344 int acpi_power_get_inferred_state(struct acpi_device *device)
345 {
346 int result = 0;
347 struct acpi_handle_list *list = NULL;
348 int list_state = 0;
349 int i = 0;
352 if (!device)
353 return -EINVAL;
355 device->power.state = ACPI_STATE_UNKNOWN;
357 /*
358 * We know a device's inferred power state when all the resources
359 * required for a given D-state are 'on'.
360 */
361 for (i = ACPI_STATE_D0; i < ACPI_STATE_D3; i++) {
362 list = &device->power.states[i].resources;
363 if (list->count < 1)
364 continue;
366 result = acpi_power_get_list_state(list, &list_state);
367 if (result)
368 return result;
370 if (list_state == ACPI_POWER_RESOURCE_STATE_ON) {
371 device->power.state = i;
372 return 0;
373 }
374 }
376 device->power.state = ACPI_STATE_D3;
378 return 0;
379 }
381 int acpi_power_transition(struct acpi_device *device, int state)
382 {
383 int result = 0;
384 struct acpi_handle_list *cl = NULL; /* Current Resources */
385 struct acpi_handle_list *tl = NULL; /* Target Resources */
386 int i = 0;
389 if (!device || (state < ACPI_STATE_D0) || (state > ACPI_STATE_D3))
390 return -EINVAL;
392 if ((device->power.state < ACPI_STATE_D0)
393 || (device->power.state > ACPI_STATE_D3))
394 return -ENODEV;
396 cl = &device->power.states[device->power.state].resources;
397 tl = &device->power.states[state].resources;
399 device->power.state = ACPI_STATE_UNKNOWN;
401 if (!cl->count && !tl->count) {
402 result = -ENODEV;
403 goto end;
404 }
406 /* TBD: Resources must be ordered. */
408 /*
409 * First we reference all power resources required in the target list
410 * (e.g. so the device doesn't lose power while transitioning).
411 */
412 for (i = 0; i < tl->count; i++) {
413 result = acpi_power_on(tl->handles[i]);
414 if (result)
415 goto end;
416 }
418 /*
419 * Then we dereference all power resources used in the current list.
420 */
421 for (i = 0; i < cl->count; i++) {
422 result = acpi_power_off_device(cl->handles[i]);
423 if (result)
424 goto end;
425 }
427 /* We shouldn't change the state till all above operations succeed */
428 device->power.state = state;
429 end:
430 if (result)
431 printk(KERN_WARNING PREFIX "Transitioning device [%s] to D%d\n",
432 device->pnp.bus_id, state);
434 return result;
435 }
437 /* --------------------------------------------------------------------------
438 FS Interface (/proc)
439 -------------------------------------------------------------------------- */
441 static struct proc_dir_entry *acpi_power_dir;
443 static int acpi_power_seq_show(struct seq_file *seq, void *offset)
444 {
445 struct acpi_power_resource *resource = NULL;
448 resource = (struct acpi_power_resource *)seq->private;
450 if (!resource)
451 goto end;
453 seq_puts(seq, "state: ");
454 switch (resource->state) {
455 case ACPI_POWER_RESOURCE_STATE_ON:
456 seq_puts(seq, "on\n");
457 break;
458 case ACPI_POWER_RESOURCE_STATE_OFF:
459 seq_puts(seq, "off\n");
460 break;
461 default:
462 seq_puts(seq, "unknown\n");
463 break;
464 }
466 seq_printf(seq, "system level: S%d\n"
467 "order: %d\n"
468 "reference count: %d\n",
469 resource->system_level,
470 resource->order, resource->references);
472 end:
473 return 0;
474 }
476 static int acpi_power_open_fs(struct inode *inode, struct file *file)
477 {
478 return single_open(file, acpi_power_seq_show, PDE(inode)->data);
479 }
481 static int acpi_power_add_fs(struct acpi_device *device)
482 {
483 struct proc_dir_entry *entry = NULL;
486 if (!device)
487 return -EINVAL;
489 if (!acpi_device_dir(device)) {
490 acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
491 acpi_power_dir);
492 if (!acpi_device_dir(device))
493 return -ENODEV;
494 }
496 /* 'status' [R] */
497 entry = create_proc_entry(ACPI_POWER_FILE_STATUS,
498 S_IRUGO, acpi_device_dir(device));
499 if (!entry)
500 return -EIO;
501 else {
502 entry->proc_fops = &acpi_power_fops;
503 entry->data = acpi_driver_data(device);
504 }
506 return 0;
507 }
509 static int acpi_power_remove_fs(struct acpi_device *device)
510 {
512 if (acpi_device_dir(device)) {
513 remove_proc_entry(ACPI_POWER_FILE_STATUS,
514 acpi_device_dir(device));
515 remove_proc_entry(acpi_device_bid(device), acpi_power_dir);
516 acpi_device_dir(device) = NULL;
517 }
519 return 0;
520 }
522 /* --------------------------------------------------------------------------
523 Driver Interface
524 -------------------------------------------------------------------------- */
526 static int acpi_power_add(struct acpi_device *device)
527 {
528 int result = 0;
529 acpi_status status = AE_OK;
530 struct acpi_power_resource *resource = NULL;
531 union acpi_object acpi_object;
532 struct acpi_buffer buffer = { sizeof(acpi_object), &acpi_object };
535 if (!device)
536 return -EINVAL;
538 resource = kmalloc(sizeof(struct acpi_power_resource), GFP_KERNEL);
539 if (!resource)
540 return -ENOMEM;
541 memset(resource, 0, sizeof(struct acpi_power_resource));
543 resource->device = device;
544 strcpy(resource->name, device->pnp.bus_id);
545 strcpy(acpi_device_name(device), ACPI_POWER_DEVICE_NAME);
546 strcpy(acpi_device_class(device), ACPI_POWER_CLASS);
547 acpi_driver_data(device) = resource;
549 /* Evalute the object to get the system level and resource order. */
550 status = acpi_evaluate_object(device->handle, NULL, NULL, &buffer);
551 if (ACPI_FAILURE(status)) {
552 result = -ENODEV;
553 goto end;
554 }
555 resource->system_level = acpi_object.power_resource.system_level;
556 resource->order = acpi_object.power_resource.resource_order;
558 result = acpi_power_get_state(resource);
559 if (result)
560 goto end;
562 switch (resource->state) {
563 case ACPI_POWER_RESOURCE_STATE_ON:
564 device->power.state = ACPI_STATE_D0;
565 break;
566 case ACPI_POWER_RESOURCE_STATE_OFF:
567 device->power.state = ACPI_STATE_D3;
568 break;
569 default:
570 device->power.state = ACPI_STATE_UNKNOWN;
571 break;
572 }
574 result = acpi_power_add_fs(device);
575 if (result)
576 goto end;
578 printk(KERN_INFO PREFIX "%s [%s] (%s)\n", acpi_device_name(device),
579 acpi_device_bid(device), resource->state ? "on" : "off");
581 end:
582 if (result)
583 kfree(resource);
585 return result;
586 }
588 static int acpi_power_remove(struct acpi_device *device, int type)
589 {
590 struct acpi_power_resource *resource = NULL;
593 if (!device || !acpi_driver_data(device))
594 return -EINVAL;
596 resource = (struct acpi_power_resource *)acpi_driver_data(device);
598 acpi_power_remove_fs(device);
600 kfree(resource);
602 return 0;
603 }
605 static int __init acpi_power_init(void)
606 {
607 int result = 0;
610 if (acpi_disabled)
611 return 0;
613 INIT_LIST_HEAD(&acpi_power_resource_list);
615 acpi_power_dir = proc_mkdir(ACPI_POWER_CLASS, acpi_root_dir);
616 if (!acpi_power_dir)
617 return -ENODEV;
619 result = acpi_bus_register_driver(&acpi_power_driver);
620 if (result < 0) {
621 remove_proc_entry(ACPI_POWER_CLASS, acpi_root_dir);
622 return -ENODEV;
623 }
625 return 0;
626 }
628 subsys_initcall(acpi_power_init);